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Executive Health and Safety

Exposure to dust and bioaerosols in poultry farming Summary of observations and data

Prepared by the Health and Safety Laboratory for the Health and Safety Executive 2008

RR655 Research Report

Executive Health and Safety

Exposure to dust and bioaerosols in poultry farming Summary of observations and data

B Crook, A Easterbrook & S Stagg Health and Safety Laboratory Harpur Hill Buxton Derbyshire SK17 9JN

This project aimed to investigate poultry farm workers’ exposure to organic dusts and associated microbiological contamination as part of the HSE Disease Reduction Programme.

The UK poultry industry (mainly the production of hens’ eggs and chicken, turkey and duck meats) involves a range of activities including laying litter, populating with young birds, depopulating (reducing bird density during growth or removing at the end of the cycle), litter/manure removal, cleaning houses after depopulation and routine ‘crop maintenance’ and housework. The objective of this study was to measure workers’ exposure to airborne dust and bioaerosols (micro-organisms and their products) associated with these tasks in a representative cross-section of commercial poultry production.

Previous studies have tended to provide only an overview of agriculture workers’ exposure to bioaerosols. However, this is of limited use in assessing health risks, because of the diversity of tasks at different times of the day, week or season. Workers’ exposure to dust and bioaerosols is certain to differ according to the task being performed. Therefore HSE was interested to obtain measurement data and to relate exposure measurements to specific tasks.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.

HSE Books

© Crown copyright 2008

First published 2008

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise) without the prior written permission of the copyright owner.

Applications for reproduction should be made in writing to: Licensing Division, Her Majesty’s Stationery Office, St Clements House, 2-16 Colegate, Norwich NR3 1BQ or by e-mail to [email protected]

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ACKNOWLEDGEMENTS

We are grateful to Robert Hadway (HSE Policy Group, Agriculture & Food Sector, Nottingham), as the Project Officer for his input to the work and help in identifying study premises, and to Nigel Black (HSE Wales & West Specialist Group) for assistance in data handling.

We are also grateful to the management and staff of the companies who participated in the collection of personal exposure data and explained their processes to HSE and HSL Occupational Hygienists and Analysts.

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CONTENTS

1 INTRODUCTION..........................................................................................1

2 PROCESS DESCRIPTION..........................................................................3

3 HAZARDOUS AGENTS ..............................................................................6

4 INHALATION EXPOSURE CONTROLS.....................................................8

5 SAMPLING AND ANALYTICAL METHODOLOGY ..................................10 5.1 Total dust................................................................................................10 5.2 Bioaerosol sampling ...............................................................................10 5.3 Microbial analyses..................................................................................11 5.4 Identification of micro-organisms............................................................11

6 RESULTS OF ANALYSES AND SUMMARISED DATA...........................13

7 DISCUSSION.............................................................................................20

8 APPENDICES............................................................................................22 Appendix A: Visit and data summaries..............................................................23 Appendix B: Photographs..................................................................................44

9 REFERENCES ..........................................................................................61

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EXECUTIVE SUMMARY Objectives


The UK poultry industry (mainly the production of hens’ eggs and chicken, turkey and duck meats) involves a range of activities including laying litter, populating with young birds, depopulating (reducing bird density during growth or removing at the end of the cycle), litter/manure removal, cleaning houses after depopulation and routine “crop maintenance” and housework. The objective of this study was to measure workers’ exposure to airborne dust and bioaerosols (micro-organisms and their products) associated with these tasks in a representative cross-section of commercial poultry production.


Main Findings

In total, eleven sampling visits to eight different farms were undertaken, covering egg production in battery and free-range or barn facilities, broiler houses and duck rearing. It was not possible to arrange to visit turkey-rearing facilities. Some farms were visited on more than one occasion to obtain data across the range of work undertaken. On each visit the data recorded included activities on site and those monitored, materials involved (directly and indirectly) and potential contaminants present, ventilation and exposure controls in place. Work task observations were performed and monitoring included total inhalable dust and airborne fungi, bacteria and endotoxins. The results showed that, at maximal exposure, poultry workers were exposed to total inhalable dust levels exceeding 10 mg/m3 during most activities. Exposure to airborne bacteria potentially exceeded one million cfu/m3 of air in each of the activities monitored. Maximal endotoxin levels ranged according to task from 30 to more than 38,000 EU/m3. Maximal airborne fungal concentrations ranged from 2,000 to 600,000 cfu/m3. The results were consistent with those from previous studies of poultry farms where an association has been made with allergic respiratory ill health.

Conclusions and Application

Commercial poultry production is a dusty business. Poultry farm workers are exposed to high concentrations of airborne dust ranging from a single substance e.g. wood dust to a complex mixture which might include inorganic and organic material derived from feed, litter, faecal material, dander (skin material), feather and micro-organisms which could cause respiratory disease including asthma and chronic bronchitis. The data from this study will be used to contribute to a ‘Statement of Evidence’, i.e., an objective summary of existing scientific information on the potential for respiratory ill health among workers exposed to poultry dust. This Statement will be used in discussions to be held with representatives of the poultry industry to raise awareness of the health risks and the need for improved controls. This work will also support the development of training and guidance material to deliver key messages to the industry.

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1 INTRODUCTION

The HSE Disease Reduction Programme (DRP) is focussing attention on three principal risks to workers health, one of which is respiratory disease. This HSL poultry survey is part of a much wider project (R52149 Dust and Bioaerosols in Agriculture) which was to investigate farm workers’ exposure to organic dusts and associated microbiological contamination.

In the UK agriculture sector there is the potential for significant exposure to a wide range of substances recognised as the causes of respiratory ill health. Some of these, e.g. grain dust, are grouped together and given a Workplace Exposure Limit, (HSE, 2006). However, exposure to other organic dusts in agriculture is also recognised as having the potential to cause respiratory ill-health. Despite these dusts being the subject of previous research studies, for example in a major European study recently completed (Radon et al, 2002,) their impact is probably underestimated within the industry. Comprehensive or systematic reviews of exposures in either the whole industry or of specific sectors are limited in number, although a recent report by Reed et al (2006) has provided a useful overview, as did an earlier HSL review for HSE (Crook et al, 2003). A further limitation of previously-published studies is that few give details of the specific tasks associated with dust or bioaerosol exposure, instead just using a generic industry descriptor. In order to provide realistic and fit-for-purpose advice to the industry, HSE wishes to collate data on specific tasks associated with high exposure to dusts and bioaerosols, so that controls can be focussed for maximum impact on these tasks. In previous work under this programme, workers’ exposure to organic dusts has been measured associated with flower bulb handling, cleaning grain silos and animal feed mixing (various reports; available from the authors on request). The current phase of the programme has been to examine poultry farming.

The UK poultry industry produces principally hens’ eggs and chicken and duck meat, with turkey meat produced on a smaller scale and various other types of meat and eggs produced only for niche markets. HSE estimates that some 30,000 people are employed in the poultry industry, although not all will be involved in farming.

The structure of the poultry industry is varied.

A relatively small number of large companies (integrated producers) perform a complete range of activities from genetics (producing their own day-old chicks) through rearing to slaughtering with direct labour, only using contractors to remove manure and clean and sterilise the houses at the end of the production cycle. At the other end of the spectrum, some “producing” companies manage virtually all of the work by keeping just the chick production and processing plant in-house, while all other activities are actually undertaken by contractors who have themselves become highly specialised to do particular tasks. Some contract growers house and feed birds between the delivery of day-old chicks and the collection of the birds for slaughter. Even tasks such as catching are commonly done by specialised gangs who may do nothing else, working either directly for a producing company or for a contractor who may only have two or three service teams. Similarly, a contract company may have a small number of two-man teams who do nothing but spread litter in cleaned houses and then set up the drinker and feeder equipment, repeating this up to six days a week throughout the year. Another contractor may have equipment and staff employed exclusively removing waste (litter and faeces) from premises and arranging its disposal.

For convenience, most of the sampling was carried out on farms either owned by, or contracted to, integrated producers so the results may not be fully representative of the industry as a whole. The survey focussed on the principal activities on rearing and production farms.

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Many of the tasks involve activities which cause other health and safety hazards, such as infection from scratches from birds’ claws, or potential musculo-skeletal disorders that could be caused by the activity of pulling birds from cages in the narrow aisles of a battery house or the lifting and reaching involved in placing adult birds in crates. These other aspects of occupational safety and health are not addressed in this work, which is focussed entirely on exposures to dusts and other particulate matter that might cause respiratory disease. The report does not cover exposure to the chemicals that are used on poultry farms

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2 PROCESS DESCRIPTION

The industry may be subdivided into the following major segments:

• (Hens’) egg production

• Broiler chicken production

• (Table) duck production

• Turkey meat production

Some processes are common to several or all sectors, such as the production of day-old chicks. There are also similarities between some other processes in different sectors, and a few activities are unique to one sector. In addition, any one activity may be performed by a range of methods, depending for example on how mechanised a particular company has become or how far it has developed an investment programme.

Typical facilities:

The industry operates using housing of two principal types.

The vast majority of buildings are single-storey sheds. These are relatively unsophisticated structures, typically 8 metres wide by 45 m long and less than 2 metres high at the eaves, on wooden frames with 2 internal rows of support columns. They usually have ridge ventilators and more recent sheds have low-level wall-mounted extractor fans along the length of the building, using the ridge ventilators as air inlets. Some modern houses have both inlet and exhaust fans mounted in the roof on either side of the ridge. Shallow ventilators at eaves height are common and only one location (a duck rearing facility) was seen which allowed natural light in, through deep wire mesh “windows.” All other sheds seen were lit entirely artificially and at all locations feed and water were supplied automatically by chain conveyor and pipe respectively.

The flooring was generally concrete, but some older sheds were seen which still had earth floors, uneven and holding water after cleaning.

The birds are housed on a variety of types of litter. Economy is important and suppliers frequently propose new alternatives. Types of litter seen have included “milled wood fibre” or wood “shreds” (effectively sawdust produced by hammer-milling softwood off-cuts), plain untreated straw and chopped straw treated with mould-inhibitor. The use of shredded paper has been reported, as has chopped oilseed rape haulm.

The other type of housing is used on egg production farms which operate on the cage or battery system, where considerable investment has been made by some producers. One farm visited consisted of three linked multi-storey sheds, connected by a common walkway which contained the egg-conveyor feeding a separate packing-house. The ground floor of each of the three sheds formed the manure “pit” and was approximately 100 m in length by 15 m wide and 8 m high. Above these were two floors of cages arranged in 8 double rows 4 cages high the length of the shed, holding approximately 125,000 birds per shed at the start of the laying cycle. Many roof-mounted fans (approximately 70 per shed) ensured that air was propelled down through the laying floors and exhausted through the droppings pit.

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One building was seen of an intermediate style, where free-range laying hens were housed. This had accommodation for the birds in a long single-storey shed divided into two halves by a central packing area. Each half was divided lengthwise by two double tiers of nest boxes back-to-back, from which eggs were conveyed to the packing areas.

A brief over-view of segment activities is given below:

Hens egg production:

Day-old chicks produced at hatcheries (where eggs collected from housed birds are incubated until they hatch,) are transported to specialised rearing farms. During rearing, the birds are generally housed in simple single-storey sheds on litter such as sawdust or chopped straw. They are fed with crumb or meal which is delivered in bulk and distributed round the house by a pair of flight chain conveyors which run the length of the house. Water is supplied from overhead pipes into numerous circular troughs which are refilled automatically via spring-loaded valves. On delivery the trays of day-old chicks are tipped into a restricted part of the house and are able to eat and drink from the equipment at floor level. As they grow they are allowed access to a bigger proportion of the shed and the feed conveyors and the drinkers are progressively raised to prevent fouling. Chicken faeces are relatively dry so the initial floor covering of litter is able to provide enough absorbency so that further applications are unnecessary.

When the birds reach about 16 weeks old they are removed to the egg production farms. This work is normally carried out by contractors. The birds are herded and penned so that catchers can pick them up by the feet; they are then passed to a station where they are vaccinated before being placed into modules for transport to the laying farms. The transport modules seen are made of wire mesh on a wheeled frame 6 cages high, each cage holding up to 10 birds. The modules are transported on closed curtain-sided articulated lorries to the laying farm. Contractors’ staff remove the birds from the modules and place them in their laying accommodation.

In the case of battery-housed laying birds, the appropriate number (5 birds in the case seen) were placed into each cage by the contractors, and the permanent farm staff then took over the care of the birds.

For free-range egg production point-of-lay birds from the same source are placed under low light onto the perching platform of the shed, which supports the feeders and drinkers and gives access to the nest-boxes. When they have adapted to the new surroundings they are allowed daytime access to the paddock adjacent to the shed.

Routine work in both types of laying facilities consists of walking through the flocks checking feed and water supply equipment and removing sick or dead birds (all daily), and cleaning of egg conveyors and walkways, etc. (weekly or fortnightly.)

On completion of the laying cycle the birds are sent for slaughter. They are caught (free range) or removed from cages by some of the contractor’s staff, handed to others (“runners”) and packed into modules of 12 crates each holding approximately 12 birds. The work is intensive until the waiting lorry has been fully loaded at which point the depleting gang take a break. The despatch of lorry loads of chickens is arranged so that they can be processed promptly on arrival at the abattoir.

Manure removal generally takes place at the end of each laying cycle. After the birds have been removed the staff of the free-range production farm dismantle and remove all the shed equipment other than the nest boxes and egg conveyors. The equipment is subsequently cleaned by separate contractors working outside in the open air. At the battery unit the shed staff also

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use scrapers and blowing tools (compressed air) to start the cleaning of the cages and egg conveyor machinery. The contractor’s staff use a small skid-steer loader to dig out the heap of accumulated manure and load it into trailers for transport to fields where it would be used as fertiliser. The trailers are reversed into the ground-level manure “pit” under the battery shed and the loading occurs there, while in the smaller free-range sheds seen the loader is reversed out of the shed to fill the trailer outside.

Broiler chicken production

These birds are bred to reach slaughter weight as rapidly as possible after hatching. Day-old chicks are transferred from hatcheries to the growing farms where they are housed in single-storey sheds in a way very similar to the initial growing of the laying birds. Farm staff monitor the condition of the birds daily, adjust feed and water equipment as necessary and administer vaccines. Catching and transport of mature birds are the same as for free-range laying birds. . After depopulation the manure-removal contractor worked in the same way as at the free-range shed. In this instance he had arranged disposal of the relatively dry manure as fuel at a power station, so it was loaded via an elevator into articulated tipper lorries for the journey.

(Table) duck production

This sub-sector is directly analogous to the production of broiler chickens or of egg-producing hens to point-of-lay. The significant difference is that duck faeces are wet, so that fresh litter has to be applied every day or two during the rearing period. This may be done manually, or by mechanised shredding of a big bale and distribution by a machine behind a tractor. The mature birds are picked up and carried by the neck because of relative weight and limb strength when compared to hens.

The organisation of the sector is mixed, as one example will show: A large processing firm produces the day-old chicks and distributes them either to its own farms or to those of contract growers. The contractor provides the housing, but uses the production company’s litter and feed until the birds are collected, either by the company’s catching gang or by independent specialist contractors. Some birds are raised entirely by the organising company on its own farms using directly-employed labour throughout. However all manure is removed by a specialist contractor, before yet another contractor performs the heavy cleaning and possibly another the sterilisation of the sheds.

Turkey meat production

Due to an outbreak of disease in East Anglia it was not possible to make any sampling visits to turkey-producing farms. However, the processes involved are understood to be very similar to the production of table chickens or ducks.

Catching

All catching of birds in the UK is believed to be by hand. Automated systems have been developed and have been trialled here but have not been adopted.

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3 HAZARDOUS AGENTS

Virtually every stage of work across the industry could result in exposure to inhalable particulates capable of causing irritation, or allergic or toxic respiratory disease.

The various types of litter on which floor-housed birds are kept provide a good example. When litter is laid in a sterilised house the only inhalation risk arises from the nature of the material itself. However the range includes the following materials:

a) Softwood shreds or shavings are commonly used, but with a significant inhalable dust content even if described as shredded wood. Softwood dust is known to cause respiratory sensitisation, i.e. it causes asthma. Hardwood dust, should it be present, is also a carcinogen. Both are subject to a Workplace Exposure Limit (WEL) of 5 mg.m-3 in the UK (HSE 2005, as amended 2007) As softwood dust is given the “Sen” (i.e. sensitiser) marking in EH40 there is an over-riding obligation to reduce exposure as low a level as is reasonably practicable (CoSHH Reg 7 (7) (c) (ii).

b) Straw (chopped or whole) and straw-like by-products of any other field crops (e.g. oilseed rape) will naturally carry a population of fungi, which will vary in type and quantity depending upon the material and the conditions under which it was harvested and stored. Long term or repeated exposure to high concentrations of fungal spores is well known to cause respiratory diseases such as “Farmers’ Lung.”

Placing new chicks onto clean litter may expose workers to the proteins in feather debris or dander, which in many other employment contexts have been found to be a serious cause of respiratory sensitisation.

Adding fresh straw litter during the growth of ducks may result in heavy exposure to both inhalable dust and to fungal spores, partly as a consequence of microbial degradation of the straw. This is of course the classic cause of Farmers’ Lung. Although every attempt is made to source clean straw and store it well, while straw is used this risk will remain.

Fortunately it is not generally necessary to undertake the laying of fresh straw litter when raising or keeping chickens on a bed of litter. Crop inspection requires daily or more frequent contact: all housed birds, hens, ducks and turkeys are inspected regularly to check on their condition, to ensure that the feeders etc are functioning properly and to remove any birds that have died or need to be culled. This task inevitably requires a significant amount of time to be spent in an atmosphere containing proteinaceous dust from the birds, a respiratory sensitiser in many analogous situations. During this activity the original litter (or as much as survives) will be disturbed to some extent, but will have been progressively added to by accumulating faeces and spilled food. Faeces contain bacteria from the birds’ natural gut flora and decomposition will allow a further population of different types to grow. Many of these bacteria are capable of causing gastro-intestinal infections and a large proportion are Gram negative species. All Gram-negative species yield endotoxins on breakdown of the cell wall, exposure to which may cause serious chest diseases, among them acute Organic Toxic Dust Syndrome, (short term influenza-like symptoms with possible long term decrement in lung function,) and Chronic Obstructive Pulmonary Disease (COPD) (Sigsgaard et al, 2005).

The routine cleaning of houses holding caged birds may expose workers to dust containing feather and mite debris and feed particles.

Catching birds either at point-of-lay after initial rearing for egg production or to depopulate houses is likely to cause significant exposure to the protein-containing dust described above. In 6

addition to feather protein and dander there is also the risk of exposure to a wide range of mites and their debris. Household dust mites, recognised as one of the major causes of asthma in the general population, have been reported as present in poultry dusts in several studies, as have storage mites, a common cause of allergy amongst farmers. In addition to these two groups of mites, red poultry mites may also be present.

When ducks are caught they are lifted from the ground by the neck, increasing slightly the distance from the workers breathing zone to the source of the dust and possibly reducing exposure slightly. However depopulating a battery laying house of hens requires the rapid removal of several birds at once from cages, half of which are at or above head height. The birds naturally spread their wings to resist the movement and the feathers are therefore rubbed along the wire mesh cages, a very effective way of generating dust.

Finally, after depopulation, the sheds are emptied of manure and cleaned. The removal of the manure and of chicken shed furniture from free-range houses (boxes, perches etc.) by the farm staff may generate heavy exposure to dust and associated bioaerosols. The cleaning activities themselves may also give rise to heavy exposure to these contaminants

This report does not consider the potential exposures to the other agents used to sterilise or fumigate the houses, either as they affect the cleaning operatives or the staff who lay litter at the start of the next production cycle.

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4 INHALATION EXPOSURE CONTROLS

The comments that follow are observations made during the site visits arranged to observe the range of activities in the sector. There is no reason to suspect that the standards of personal protection or organisation of work were not representative of general practice. The visits were to organisations that agreed to co-operate with this research work and were also to large companies that made tracing the differing activities practicable. Both these factors might have influenced the level of health and safety management and outcomes which were then observed and could have led to observations of better-than-average performance.

Ventilation in the houses accommodating poultry is generally intended to maintain a comfortable atmosphere for the birds. The dust generated during tasks such as spreading clean litter or removing manure may be slightly reduced by the operation of shed ventilation systems. Some reports suggested that farm managers were reluctant to operate ventilation for the benefit of contractors, probably because of energy costs. Where exposure is recognised as potentially harmful, reliance is usually placed on respiratory protection of one sort or another

A visor supplied with filtered air from a small fan mounted on the cap peak was seen in use as dusty wood shavings were spread in a deep-litter house. It appeared to be a suitable item of RPE in the circumstances of use. However its value was undermined by the difficulty which the users found in obtaining replacement filter cartridges.

Poor-quality straw litter being spread manually during duck rearing generated high dust and microbial exposure: the FFP2 disposable filtering facepieces in use could have been replaced by FFP3 items with significant benefit in exposure reduction.

Many of the tasks which cause exposure to airborne contaminants involve significant physical activity, often in areas of restricted access. This combination of factors imposes limitations on what RPE can practicably be worn, and much work is at present performed without any kind of RPE. An extreme example was found to be the depopulating of hens from battery laying houses. The heavy physical exercise involved and the restricted space between the cages would probably make any RPE heavier than a filtering facepiece unacceptable to the wearer. This activity was almost exclusively performed by casual labour working for a contractor, and no RPE was available to them. This was not the case during the duck-depleting, however, where directly-employed staff were supplied with FFP1 facemasks, face-fitted and subject to Occupational Health surveillance.

Hand-held blowers were used for a variety of tasks including routine housework in the battery farm. After depopulation compressed air was used to blow away the feed remaining in the feed conveyors which created dust exposure of nearly 70 mg.m-3; a powered helmet respirator was used during this work,. For other routine cleaning work FFP2 facepieces were available, albeit stored in unhygenic conditions. The industry needs to critically examine cleaning methods to reduce worker exposures. Compressed air delivered through a primitive lance was also used at some broiler farms to remove dust from the ventilation fans and their housings as part of the end-of-cycle shed cleaning. The use of high pressure water jets to clean shed equipment also generates aerosols of dried faeces: no face or respiratory protection was used during this work.

The spreading of fresh litter in duck rearing houses has been automated to a certain extent, where houses have been modified to accommodate it. A tractor tows a straw chopper that carries, shreds and distributes a big bale of straw to one side as it passes down the length of a house. In some cases it exits the shed, picks up a second bale and completes the job during a second pass back through the house. However this might not prevent exposure for two reasons.

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It still requires one member of staff to walk in front of the tractor to herd the ducks out of the way, which will mean either walking back through the dust created on the first pass if the air is still, or walking in the dust being blown ahead of the tractor in one direction if a strong directional flow is present. If the cab is not supplied with filtered air from a well-maintained system the tractor driver will also suffer exposure for the same reasons.

Manure removal was usually by a small skid-steer type of loader which was not fitted with any cab ventilation (and hence filtration.) It was used with the side window open to aid vision, however the FFP2 facepieces freely available to staff were not always used.

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5 SAMPLING AND ANALYTICAL METHODOLOGY

5.1 TOTAL DUST

Total Inhalable Dust (TID) was measured using IOM Personal Inhalable Sampler. This is a conductive plastic sampling head that collects airborne particles onto the surface of a filter housed in a reusable 25-mm filter cassette. When attached to a personal sampling pump operating at 2 l/min and clipped in a worker’s breathing zone, the IOM effectively traps particles up to 100µm in aerodynamic diameter and closely simulates the manner in which airborne workplace particles are inhaled through the nose and mouth (Fig 1). IOM samplers are recommended samplers for workplace measurement of Total Inhalable Dust (TID) by weighing as a single unit the cassette and filter before and after sampling (MDHS 14/3; HSE, 2000).

IOM samplers were operated for as long as possible to obtain data representative of selected work activities and data calculated as mg.m-3 dust. These data were also used to calculate 8-hour equivalent time-weighted averages (TWAs) for a full work shift, but as some of the activities lasted for short periods, in some cases less than one hour, TWA values should be treated with caution.

Fig 1. IOM filtration sampler

5.2 BIOAEROSOL SAMPLING

In addition to gravimetric dust sampling, in this study IOM samplers were also used to sample airborne micro-organisms and endotoxins in the breathing zone of the workers, and were also used as static samplers close to activities in some instances. The filters used in this study were Quartz filters, (Whatman QM-A), determined by HSL and others in previous studies to be optimal for retrieval of captured micro-organisms and endotoxins (Kenny et al, 1998; Reynolds et al, 2002).

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5.3 MICROBIAL ANALYSES

5.3.1 Endotoxin analysis

Filters from the IOM samplers were placed in pyrogen free tubes and the collected deposits were extracted by shaking at room temperature for 2 hours in 10ml of endotoxin free 50mM Tris buffer (Cambrex). The resulting suspension was then divided to provide samples for endotoxin analysis and microbial enumeration (see below). Samples for endotoxin analysis were then centrifuged at 1000 g for 10 minutes to remove particles, and dilutions of the supernatant were prepared for analysis.

Samples were analysed using the Kinetic-QCL automated system (Bio-Whittaker Inc., Walkersville, Maryland, USA). This system is widely accepted in the pharmaceutical industry for endotoxin free product validation in accordance with the United States’ FDA, but is also widely used for assaying endotoxin in workplace samples (Reynolds et al, 2005; Liebers et al, 2007). It is a quantitative kinetic assay based on a commercial 96 well plate assay system, with assays performed in a temperature controlled plate reader. It is validated for detection of Gram-negative bacterial endotoxin, the presence of which in a sample activates a proenzyme in the Limulus Amebocyte Lysate (LAL) reagent. This results in a colour (chromatic) change, and the concentration of endotoxin in the sample is calculated automatically from the rate of colour change, compared to controls of known concentrations. Results are expressed as endotoxin units (EU)/ml, which is a measure of the biologically available endotoxin in the sample. From other assay methods, endotoxin concentration may be expressed as nanogram (ng)/ml, and for cross reference 10 EU is the equivalent of 1 ng (assay manufacturers data). Each sample was analysed with a negative and positive control.

5.3.2 Enumeration of culturable micro-organisms

A sub-sample of the extracts prepared from filters for endotoxin analysis was used for microbial analysis. A dilution series was prepared from the initial extraction suspension in ¼ strength Ringers solution and was used to inoculate agar plates.

Total mesophilic fungi were isolated on Malt extract agar incubated at 250C for up to 10 days. Total thermotolerant fungi were isolated on Malt extract agar, incubated at 400C for up to 10 days. Total mesophilic bacteria and bacteria capable of growth at human body temperature were isolated on Nutrient agar incubated at 250C and 370C respectively. Thermophilic bacteria and actinomycetes were isolated on R8 agar and incubated at 550C for 7 days.

Following incubation, emerging colonies on agar plates were counted and, using the known volume of air sampled, numbers calculated as colony forming units (cfu)/m3. Predominant bacteria and fungi were isolated into pure culture and identified.

5.4 IDENTIFICATION OF MICRO-ORGANISMS

5.4.1 Bacterial Identification

DNA Isolation: Portions of predominant bacterial colonies cultured from poultry dust bioaerosols were suspended in 100µl H2O and lysed using lysozyme (100µl, 50mg/ml in UV

o de-ionised water [UDIW]), each mixture was incubated for 30 minutes at 37 C, with gentle mixing after 15 minutes. The lysate was then processed with the Qiagen Qiaquick Tissue Lysis

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kit (Qiagen Ltd., Dorking, Surrey) using modifications to the manufacturer’s instructions as optimised in-house at HSL (details on request). The DNA was eluted into 150 µl of warmed elution buffer, and was used as template for polymerase chain reaction (PCR) with no further purification.

PCR amplification of the 16S rRNA gene from extracted DNA: Each DNA sample was used as a template in the polymerase chain reaction (PCR). The DNA-based analysis here focused on the identification of the bacterial components from each sample. The primers used for all initial PCR amplifications have been selected on the experience of previous investigations at HSL into workplace and environmental micro-organisms. These and other primers were synthesised by Alta Bioscience, University of Birmingham.

A polymerase chain reaction (PCR) that selectively amplified the first 520 base pairs of the bacterial 16S rRNA gene was carried out with primers and reaction conditions following standard HSL protocols. The resulting PCR products were stained with ethidium bromide (0.5µg ml-1) and visualised under UV after electrophoresis on 1.5% agarose gel. PCR products were cleaned using microspin S400 spin columns prior to automated sequence analysis. Resulting sequences were then compared to the online NCBI database to characterise the micro-organism (http://www.ncbi.nlm.nih.gov/BLAST). Sequence analysis of these regions of the 16S rRNA genes provides an accurate microbial identification to the genus level, and species level identification can often be made with a high degree of confidence.

5.4.2 Presence of Salmonella

Salmonella bacteria are potential food poisoning bacteria associated with poultry and egg products and potentially present in poultry faeces. To test for the presence of Salmonella, DNA from undiluted suspensions from air samples were extracted as above and tested using a PCR protocol targeting DNA sequences unique to the Salmonella genus. Results were expressed as presence or absence in a sample.

5.4.3 Fungal identification

Fungal colonies were identified by gross morphology, microscopic examination and DNA analysis. Where DNA analysis was required, DNA was isolated as described for bacteria and primers targeting specific regions of the rRNA gene were used following standard HSL protocols for fungal PCR amplification.

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6 R A

Dpt

Ta m

Ope D /m3

8-hr Bacfu/m3 F 3 En

EU/m3

Pc

8 1 3 1

Pd

11.1 1 2 3

PS

3 N N N

Pb

1 5 1 1441

Pbm

1 8 4 6192

Pba

5 2 1120 5170

Pfm

2 9 8 558

Pfs

8 6 4 114

Pc

4 1 6 30.7

Pm

3 2 2 1140

Pc

2 2 3 623

Ps

1 2 6 224

ESULTS OF ANALYSES ND SUMMARISED DATA

ata from the eight farms are summarised in Table 1 below, which shows the maximum otential worker exposure to dust and bioaerosol at each farm, and the activity associated with hat exposure.

ble 1. Su mary of maximum exposure to dust and bioaerosols in poultry work

ration/activity ust mgTWA

cteria ungi cfu/m dotoxin

roducer 1Farm 1 duck atching

.2 5.5 million 9,333 6,600

roducer 1 Farm 2 uck laying bedding

37 million ,690 8,903

roducer 2 Farm 1 preading litter

4.8 ot done ot done ot done

roducer 2 Farm 2 attery restock

3.4 1 million 1,000

roducer 2 Farm 2 attery cleaning & ucking out

9.0 million 1,000

roducer 2 Farm 2 ttery depleting

.9 .5 million

roducer 2 Farm 3 ree range cleanout ucking out

3.7 1 million 0,000

roducer 2 Farm 3 ree range dismantling hed furniture

0.8 .1 million ,350

roducer 3 Farm 3 atching

.7 5 million ,840

roducer 3 Farm 3 ucking out

3.1 00 million 6,000

roducer 3 Farm1 hicken placing

.7 .6 million 8,000

roducer 3 Farm 2 litter preading

5.7 0 million 00,000

13

Data from the eleven visits were collated in six general categories of work activity:

• Laying litter

• Repopulating

• Depopulating

• Litter/manure removal

• Cleaning after depopulation

• Routine housework

The results of potential exposure to airborne dust, bacteria, fungi, actinomycetes and endotoxin are tabulated and summarised graphically below as box and whisker plots, to show the 25 percentile to 75 percentile range and full range of values. A more complete summary of the observations and results from each visit is included as appendix A.

The reported 8-hr Time-Weighted Average (TWA) concentrations are based on the work patterns described by the operatives. In the majority of cases staff performed only one type of work, a consequence of the level of specialisation of tasks performed by contractors. The 8-hr TWA figures for shorter term activities are given as though no other exposure to the same contaminants occurred in the same day.

In most of the cases where more than one activity is performed in a day the task-specific 8-hr TWA will be a useful value as most tasks generate exposure to unique ranges of contaminants. In addition it will be observed that data on bioaerosol exposures is reported in orders of magnitude. In these circumstances 8-hr TWA calculations are of little relevance unless exposures are the result of tasks performed for only a very brief period in a day.

14

Ta )

Lag l

Rg

Dg

Lie

Cafter

depon

Rhouse

k

N = 9 11 24 7 7 2 Mm 8 2 1 9 1 4

75% 3 8 6 8 4 4M 1 5 4 3 1 4

25% 1 3 3 2 8 4Mm 3 2 1 1 1 3

ble 2. Airborne dust concentrations associated with poultry work activities (total n=60

yin

itter

epopulatin epopulatin tter/manur removal

leaning

pulatio

outine wor

aximu value 4.5 3.8 0.4 4.7 07.7 .0

4.8 .9 .4 0.1 8.2 .0 edian 6.0 .5 .6 5.4 5.8 .0

1.6 .9 .8 9.3 .8 .0 inimu value .7 .8 .2 7.3 .6 .9

0

(9)

Re

po

pu

latin

g

(11

)

De

po

pu

latin

g

(24

)

Litte

r/m

an

ure

after

de

po

pu

latio

n

(7)

Ro

utin

e

ho

use

wo

rk

(2)

mg

/m3

Total inhalable dust

20

40

60

80

100

120

La

yin

g litte

r

rem

ova

l (7

)

Cle

an

ing

Fig 2. Total inhalable dust concentrations in poultry farms associated with work activity

15

Tan= )

Ll

R D L /r

Ca

d u

Rh

N = 5 11 25 7 8 2 M

v 1 8 5 7 1 7 4 7 2 8 1 6

75% 7 7 1 7 9 6 1 7 3 7 1 6

M 2 7 8 6 2 6 6 6 5 6 1 6

25% 1 7 1 6 8 5 4 6 1.2x106 1 6

Mv 5 5 9 5 1 3 3 6 7 4 1 6

ble 3. Airborne bacterial concentrations associated with poultry work activities (total 59

aying itter

epopulating epopulating itter manure emoval

leaning fter

epop lation

outine ousework

aximum alue .4x10 .1x10 .6x10 .1x10 .0x10 .4x10

.7x10 .5x10 .3x10 .3x10 .8x10 .3x10edian .0x10 .4x10 .0x10 .1x10 .2x10 .2x10

.1x10 .7x10 .0x10 .8x10 .1x10inimum

alue .5x10 .9x10 .7x10 .3x10 .0x10 .1x10

Fig 3. Total airborne bacterial concentrations in poultry farms associated with work activity

16

Ta tin= )

Lal

R D Lire

Cafter depo

Rho

N = 5 11 25 7 8 2 M

v 6 5 3 4 3 4 8 4 2 4 6 3

75% 3 5 3 4 9 3 2 4 1. 4 4 3

M 4 4 1 4 2 3 1 4 9 3 3 3

25% 2 3 7 3 5 2 8 3 6 3 2 3

Mv 2 3 7 2 9 1 3 3 4 3 1 3

ble 4. Airborne fungal concentrations associated with poultry work activi es (total 58

ying itter

epopulating epopulating tter/manure moval

leaning

pulation

outine usework

aximum alue .0x10 .8 x10 .9 x10 .1 x10 .7 x10 .0 x10

.3 x10 .4 x10 .9 x10 .9 x10 5 x10 .8 x10edian .2 x10 .1 x10 .5 x10 .5 x10 .5 x10 .7 x10

.7 x10 .6 x10 .1 x10 .7 x10 .2 x10 .5 x10inimum

alue .2 x10 .9 x10 .3 x10 .6 x10 .4 x10 .3 x10

(5)

(11

)

(25

)

Litte

r/m

anure

Cle

anin

g

(8)

Routin

e

ho

use

wo

rk

(2)

cfu/

m3

Fungal cfu at 25 degrees

1.0E+00

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

1.0E+06

Layin

g litte

r

Repopula

ting

Depopula

ting

rem

oval (7

)

aft

er

depopula

tion

Fig 4. Total airborne fungal concentrations in poultry farms associated with work activity

17

Ta(to )

Ll

R D L /r

C r d

Rh

N = 4 5 10 4 4 0 M

v 1 5 9 4 1 5 6 6 1 4

75% 1 5 8 4 6 4 2 6 3 3

M 9 3 6 4 6 3 2 3 2 2

25% 2 4 7 4 1 4 1 5 4 2

Mv 9 3 6 4 6 3 2 3 2 2

ble 5. Airborne actinomycete concentrations associated with poultry work activities tal n=27

aying itter


leaning afteepopulation

outine ousework

aximum alue .3x10 .3 x10 .7 x10 .1 x10 .0 x10

.2 x10 .5 x10 .0 x10 .5 x10 .1 x10edian .4 x10 .9 x10 .9 x10 .4 x10 .2 x10

.4 x10 .5 x10 .5 x10 .3 x10 .7 x10inimum

alue .4 x10 .9 x10 .9 x10 .4 x10 .2 x10

cfu

/m3

Actinomycetes at 55 degrees

1.0E+00

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

1.0E+06

1.0E+07

Laying litter

(4)

Repopulating

(5)

Depopulating

(10)

Litter/manure

removal (4)

Cleaning after

depopulation

(4)

Fig 5. Total airborne actinomycete concentrations in poultry farms associated with work activity

18

Ta in= )

Ll

R D L /r

Ca

d

Rh

N = 5 9 25 6 5 2 M

v 3 1 1 6 4 249 75% 2 623 1 995 1 3 193

M 224 319 184 526 166 137 25% 56 261 31 373 114 81

Mv 21 25 < < < 25

ble 6. Airborne endotoxin concentrations assoc ated with poultry work activities (total 52

aying itter


leaning fter

epopulation

outine ousework

aximum alue 8,903 ,441 6,600 ,192 ,014

6,232 ,024 ,26edian

inimum alue LOD LOD LOD

Fig 6. Total airborne endotoxin concentrations in poultry farms associated with work activity

19

7 DISCUSSION

Commercial poultry production is a dusty business. In the enclosed environment of a poultry shed, poultry farm workers therefore may be exposed to high concentrations of airborne dust. Poultry dust may be a complex mixture of inorganic and organic material containing, singly or as a mixture, inert dust from soil together with organic material derived from feed, litter, faecal material, dander (skin material), feather and micro-organisms and breakdown products. The composition of the dust is likely to vary across the poultry production cycle and from activity to activity. It is also influenced by the feed and litter types.

The micro-organisms that may form part of poultry dust could cause respiratory allergies including asthma and chronic bronchitis (Donham et al, 1990, 2000; Morris et al, 1991; Nielsen et al, 1995; Radon et al, 2001), and bacterial endotoxins, parts of the cell walls of some bacteria, can trigger ‘flu-like symptoms if inhaled (Rylander and Carvalheiro, 2006; Thelin et al, 1984).

Bacteria and Endotoxins present in poultry dust bioaerosols may be derived from soil and dust generally present in any agricultural environment, from feed and bedding, and from the birds themselves (faecal or skin microflora). Their presence in large numbers or breakdown products (endotoxin) may constitute a risk to human health of workers as an immunological or toxic challenge to the respiratory system.

Fungi, like bacteria, may be present in poultry dust bioaerosols derived from soil and dust and from feed and bedding, but to a lesser extent from the birds themselves. Their presence in large numbers may represent a significant immunological challenge to the respiratory system. Long term or repeated exposure to high concentrations of airborne fungal spores in a range of agricultural environments is recognised as contributing to decline in lung function and allergic disease such as asthma and allergic alveolitis, e.g., Farmer’s Lung disease. The main source of fungi in poultry houses is likely to be from feed and bedding. Fungi naturally present for example in bedding material such as straw will multiply in the moist conditions. There may also be a progression of development of thermophilic (heat loving) fungi as the predominant species if conditions in, for example, deep litter become similar to those in composting organic materials. Some of these thermophilic species such as Aspergillus fumigatus are recognised respiratory allergens as well as being potential pathogens, causing lung infections in humans, albeit usually in immunocompromised individuals, and also can cause economic losses through lung disease in birds.

Mites may be present in many of the media involved in poultry farming and many species of mite have been implicated as causes of respiratory sensitisation. These range from the household dust mite (widely recognised as a cause of asthma) through a variety of storage mites to simple parasites of the birds themselves.

Previous studies have tended to provide only an overview of workers’ exposure to bioaerosols in agricultural work. However, this is of limited use in developing a risk assessment, because agricultural work involves a diversity of tasks at different times of the day, week or season. A worker’s exposure to dust and bioaerosols is certain to be different according to the task done, therefore it is of interest to HSE to obtain measurement data of workers’ exposure to bioaerosols and also to relate these exposure measurements to specific tasks.

The aim of the study in the poultry industry was to cover the main activities associated with broiler and egg production, including both housed and free range birds, and duck rearing. It was not possible to cover turkey rearing within the study period although some of the associated

20

activities were observed during an earlier phase of the project and virtually all are directly comparable to similar activities elsewhere in the industry. Specific activities have included litter handling (laying down and mucking out), bird handling (placing, depleting and catching) and general maintenance and service activities.

The results have shown the extent to which poultry workers may be exposed to dust and bioaerosols whilst undertaking a range of typical work activities. At maximal exposure, total inhalable dust levels exceeded 10 mg/m3 in most instances, emphasising the need for protection from this level of dust, even before considering its biological content. Exposure to airborne bacteria potentially exceeded one million cfu/m3 air in each of the activities monitored. Maximal endotoxin levels ranged according to task from 30 to more than 38,000 EU/m3. Maximal airborne fungal concentrations ranged from 2,000 to 600,000 cfu/m3.

It was not always possible to predict high levels of one from the other, for example, where dust levels were particularly high, sometimes microbial levels were relatively low; and where bacterial levels were high, mould levels were relatively low. This showed the importance of measuring each parameter in this study.

There are no workplace exposure limits for bioaerosols, therefore to put the above information into context it is important to compare it to existing data from previous studies, especially those where allergic respiratory ill health has been reported. The concentrations of bacteria in poultry dust bioaerosols have been cited in previous published studies to range from 100,000 to

36 million cfu/m , with a mean value of 289,000 cfu/m3 (Radon et al, 2002).

A health-based exposure limit of 50 Endotoxin Units/m3 was proposed in the Netherlands in 1997. This was based on an experimental study of human exposures to organic dusts (cotton dust) with varying endotoxin content. Field observations suggested that this health-based limit would be very difficult to achieve in practice and a temporary legal limit of 200 EU/m3 was subsequently adopted by the Dutch government.

Published data on poultry workers’ exposure to fungi is limited, although one study relating exposure to respiratory disease gave a median exposure of 440,000 cfu/m3 ranging from 14,000 to 110 million cfu/m3 air (Radon et al, 2002).

By comparison to other industries, bacterial levels are similar to farmers harvesting grain, or workers handling compost or domestic waste at transfer stations, with fungal levels lower than in these industries (Swan et al, 2003).

The data from this study will be used to contribute to a ‘Statement of Evidence’, i.e., an objective summary of existing scientific information on the potential for respiratory ill health among workers exposed to poultry dust. This Statement will be used in discussions to be held with representatives of the poultry industry to raise awareness of the health risks and the need for improved controls. This work will also support the development of training and guidance material to deliver key messages to the industry. Future work is likely to focus on the practical controls available, mainly comfortable and effective respiratory protection

21

8 APPENDICES

22

APPENDIX A: VISIT AND DATA SUMMARIES

In total, eleven sampling visits to eight different farms were undertaken to obtain data representative of work activities in the UK poultry industry. Some farms were visited on more than one occasion to obtain data from the range of work undertaken.

On each visit the following data were recorded:

• Industry sector

• Employer

• Location

• Visit Date

• Activities on site

• Activities monitored

• Materials involved (directly and indirectly) and potential contaminants present

• Ventilation

• Exposure controls in place

• Work task observations

• Monitoring Results – Total Inhalable Dust or Particulate) (TID) and bioaerosols

The following abbreviations are used in the tables of exposure data:

Sample Type: PL:- Personal, Long-term, PS:- Personal, Short-term, SL:- Static (i.e. Background) Long-term, SS:- Static Short-term (i.e. a measurement of task-based exposure.),

Nd,:- Not detected

Nr:- not recorded

Units:

cfu/m3:- Colony-forming units per metre cubed (of air sampled)

EU/m3:- Endotoxin Units per metre cubed (of air sampled)

23

Sampling Visit record summary: Visit 1

Industry sector: Table Duck production

Employer: Producer 1

Location: Farm 1.

Visit Date 31 Aug 2006

Activities on site: Contract rearing of ducks from day-old to slaughter weight. Catching activity performed by the company’s own employees.

Activities monitored: Catching ducks, placing in crates & loading lorry for transport to factory.

Materials involved (directly and indirectly) and contaminants: Duck down and dander, mites, microbial contamination of used litter.

Ventilation: Large doors open at both ends of shed. Wire mesh unglazed window openings along the sides. Exhaust vents along shed roof (Powered in older houses, since approx 1990 roof vents designed to aspirate naturally.) Noticeable hot humid airflow off ducks, especially each time they were driven, venting from side windows at downwind end.

Exposure controls in use: FFP1 facemasks in use but not always worn properly (e.g. 1 strap only used). Staff wore own clothes but laundered by company. Qualitative face-fit testing (Bitrex test) performed in-house. Work activities rotated among members of catching gang Health surveillance operated for 10 years.

Observations: Catchers employed at factory, transported to site by Producer 1minibus and may be taken to a second farm during their shift. Typical hours 02.00 to 14.00 when catching at this location.

Staff work 3 12-hour shifts per week throughout the year except for holidays. Occasional Saturday overtime not welcomed. Staff reported generally not to have other employment.

Monitoring Results: The catchers’ exposure to inhalable dust ranged from 3.1 to 4.9 -3mg.m-3 with an outlier at 8.2 mg.m . The fork lift truck driver in the gang

had slightly higher exposure than the majority of the catchers, as the lorries were being loaded at the downwind end of the shed. The workers might work at catching for a maximum of 8 hours in a day, net of travelling and breaks and the 8-hr equivalent TWA exposures are therefore the same as those measured during “catching including breaks.”

24

RNumber

Satype

Sa n (e.ta /

Saperi

Durati( )

R(m -3)

8-hr TWA

(m -3)

07124/06 PL 1 0 –1 150 8 8

07125/06 PL 2 0 –1224 268 4 4

07126/06 PL 3 0 –1 268 4 4

07127/06 PL 4 0 –1 233 4 4

07128/06 PL 5 0 –1 233 3 3

07129/06 PL 6 0 –1 207 3 3

07130/06 PL 7 S 08:55–1 205 3 3

07131/06 PL 8 W 09.05–1 82 4 4

07132/06 PL 9 0 –1 78 3 3

07133/06 PL 1 0 –1 190 1 1

R rence N

MF2

A4

F4

Am

5

Ba2

Ba3

En in EU/m3

air 0 / 3 4 1 3 2 3 5 4 1 7 1 6 16600

0 / 1 4 750 932 9 3 6 6 2 7 2462

0 / 1 4 559 1 3 6 4 9 6 3 7 3917

0 / 9 3 ND 858 7 4 9 6 1 7 1931 0 / 1 4 ND 1 3 3 4 1 7 2 7 1094

0 / 2 4 241 2 4 1 5 1 7 1 7 714

0 / 2 4 1 4 2 4 2 4 7 6 9 7 1024 0 / 2 3 60 121 1 4 1 6 2 6 140

0 / 2 3 ND 64 6 3 1 6 2 6 ND

0 / 3 3 526 263 2 4 1 7 6 5 ND T t

N ( /m3)

eference mple mple descriptiog. name/ sk/process equipment)

mple od

on Mins

esult g.m g.m

: FS catching ducks 7.47 0.17 .2 .2

: JB catching 7.56 .01 .01

DA catching 7.52 2.20 .35 .35

DF catching 8.25 2.18 .00 .00

DS catching 8.27 2.20 .72 .72

SA catching 8.54 2.21 .79 .79

H catching 2.20 .07 .07

W, FLT Driver 0.27 .94 .94

WS, catching 9.09 0.27 .85 .85

0 FT, catching 9.12 2.22 .18 .18

efeumber

esophilic ungi 5°C

. fumigatus 0°C

ungi 0°C

ctino ycetes 5°C

cteria 5°C

cteria 7°C

dotoxof

7124 06 .93 x 10 .00 x 10 .67 x 10 .57 x 10 .55 x 10 .89 x 10

7125 06 .73 x10 .70 x 10 .03 x 10 .11 x 10

7126 06 .64 x10 .87 x 10 .16 x 10 .33 x 10 .77 x 10

7127 06 .87 x 10 .94 x 10 .27 x 10 .35 x 107128 06 .46 x 10 .07 x 10 .65 x 10 .14 x 10 .81 x 10

7129 06 .10 x 10 .95 x 10 .71 x 10 .14 x 10 .20 x 10

7130 06 .58 x 10 .29 x 10 .71 x 10 .24 x 10 .83 x 10 .22 x 107131 06 .19 x10 .34 x 10 .43 x 10 .03 x 10

7132 06 .69 x 10 .92 x 10 .99 x 10 .31 x 10

7133 06 .42 x10 .03 x 10 .13 x 10 .71 x10ests for Salmonella bacterial species all nega ive.

D = None Detected LOD = 50 cfu

25


Industry sector: Table Duck production


Location: Farm 2.

Visit Date 9 October 2006

Activities on site: Rearing ducks from day-old to slaughter weight.

Activities monitored: Manual daily addition of litter by direct employees (in houses not yet converted for mechanical litter spreading.)

Materials involved (directly and indirectly) and contaminants: Straw and microbial contamination (innate, plus significant decay noticed)

Ventilation: Sheds have small wire mesh-covered unglazed window openings along sides and eaves ventilators. Extra ventilation is by vents at roof height, but some cross-draught flows through houses.

Exposure controls in use: 3m FFP1 disposable facemasks. Fabric overalls issued, uniquely coloured for each farm

Observations: Directly-employed staff work five 8-hour shifts per week throughout the year except for holidays. Men work in pairs: Enter houses, undo string round one of the big (oblong) bales on stillages, break off a 10-cm piece, fold it to break it then walk round teasing off straw and sprinkling it between birds, repeating until a thin layer of straw added all round the house. Straw being spread 9/10/06 noted to have black stain for 10 cm on one side of bale as though had stood on wet ground and started rotting.

Usually one pair do the manual littering, taking 2 hours (4 man-hours), on this occasion another pair had done half of it first.

Monitoring Results: The two workers monitored had very similar inhalable dust exposures of approximately 84.4 ± 0.1 mg.m-3 during the hour they performed the task, but another pair of workers had already started and done some of the work, which was not the usual pattern. Normally one pair alone would do the job, with 2 hours exposure. The 8-hour equivalent TWA would therefore be 21.1 mg.m-3.

26

RN

Satype

Sa(e.

na /

Saperi

Durati( )

R(m -3)

8-hr TWA

(m -3)

078 / PL C( ) 0 – 63 8 1

0 / PL A 0 – 63 8 1

Tco

R rence N

MF

A. fu

4

F4

A -m

5

Ba2

Ba3

EnEU/m3

air 0 / 2 3 60 121 1 5 1 8 1 7 38903

0 / 2 3 ND 64 2 4 7 7 7 6 26232

N ( /m3)

eference umber

mple mple description g.

me/task/process equipment

mple od

on Mins

esult g.m g.m

03 06 S, Manually spreading straw litter growing ducks 7.41 08.44 4.25 1.1

7804 06 G, Manually spreading straw litter 7.41 08.44 4.49 1.0

he exposures to bioaerosols were also high, probably as a consequence of the rotted or ntaminated straw that was noted.

efeumber

esophilic ungi 25°C migatus

0°C

ungi 0°C

ctinoycetes 5°C

cteria 5°C

cteria 7°C

dotoxin of

7803 06 .19x10 .20x10 .37x10 .58x10

7804 06 .69x10 .84x10 .73x10 .48x10


27


Industry sector: Egg Production


Location: Farm 1

Visit Date 06 July 2006

Activities on site: Rearing laying birds from day-old to point-of-lay.

Activities monitored: Placing deep litter into houses before introduction of day-old chicks by specialist contractor

Materials involved (directly and indirectly) and contaminants: “Wood shreds” (actually hammer-milled untreated virgin softwood, not passed through any dust extraction stage.) Material bulk-delivered, not dust extracted.

Ventilation: 6 traditional poultry sheds (of timber construction, some with bare earthen floors,) double doors at each end (far end closed during litter spreading.) Mechanically ventilated – extraction fans in side-walls draw air into sheds from open vents in roof line. Extract fans along sides of houses, all running full speed during litter spreading, inducing strong inward draught at shed front doors.

Exposure controls in use: · “Aircap 2” ventilated visor (Aircap 2 fabric cap + ventilated visor + twin cartridge filters manufactured by Bradwest Safety Co Ltd, EN 12941:1998 TH1 100BTH1 CE 0086 – Filters: En1294:1998 TH1P)

Observations: Bedding contractors work 10-15 hours/day and 6/7 days/week throughout the year (except for holidays.) Do both this type of work and setting up shed (arranging feeder and drinker equipment) before birds introduced.

Moving-floor delivery vehicle discharges litter from rear of trailer onto yard in front of open shed doors. One of contractor’s staff uses small John Deere tractor (Model 4100) with wide front-end bucket to move litter into shed - forms large heap just inside shed entrance where available for spreading. Litter is spread inside the sheds using a cowl/hood mounted on the back of a small tractor driven by colleague. Dust is raised from spinning tractor wheels as well as the blade as it ploughs into the heap at the shed entrance and as the tractor drives around the shed depositing the litter across the floor. Aim to provide an even bed 2 to 3 inches deep. Drives around shed in random pattern. After moving litter into shed, tractor driver clears up spillages in shed entrance and residues from yard outside. This involves both shovelling dry litter and clearing the ground using the blower. Off-loading driver completes spreading by hand i.e. rakes litter around posts and into corners.

28

M :

RN

Satype

Sa(e.

na / )

Saperi

D( )

R(m -3)

8-hr TWA

(m -3)

05487-06 PS Cl 1 –1 31 3 3

05488-06 PL C - 5 a -r 12 –1 131 1 1

05486-06 PL CLob

0 –1 90 2 2

05482-06 PL Csr

1 –1 100 5 5

Cod 8-h

onitoring Results

eference umber

mple mple description

g. me/task/process equipment

mple od

uration Mins

esult g.m g.m

ontr. Employee 1, tractor spreading itter in house #2 0.50 1.21 4.8 4.8

ontr Employee 1 ditto, houses 3 nd hand aking. .57 5.08 6.0 6.0

ontr Employee 2 using Front End ader to put shavings into house,

lowing residue in. 9:55 1.25 9.2 9.2

ontr Employee 2 using F.E.L. to put havings into houses, blowing esidue in.

3.30 5.10 .84 .84

ntactors do work at farms as far as 3 or 4 hours travel from home, either end of the working ay. r TWA therefore based on 8 hours exposure.

29


Industry sector: Egg production


Location: Farm 2

Visit Date 07 November 2006

Activities on site: Producing eggs (caged birds over deep pit) also grading & packing eggs in separate building.

Activities monitored: Depopulating by specialist contractor

Materials involved (directly and indirectly) and contaminants: Feathers, dander mites and some faeces.

Ventilation: Normal shed ventilation (Supply fans in roof blow air down through 2 floors of cages venting through droppings pit on ground floor) plus airflow through “Teagle” opening.

Exposure controls in use: some rotation of work tasks, otherwise none. Catchers work intensively to fill lorry then await appropriate time to fill next, may work 4 hrs. max in shift

Observations: Very physical work, in relatively restricted areas. Birds pulled from 4 tiers of cages, top 2 at about or above head height, then handed to “runners” who gave birds to gang-member who loaded crates. The gang rotated the cage-emptying and crate filling work.

30

M ng

Site R rence N

Satype

Sa(e.

na /p

Saperi

Durati( )

R(m -3)

8-hr TWA

(m -3)

A

1 / PL 1 0 -1 273 1 01 / PL 2 0 -11: 271 5 3

1 / PL 3 0 -1 272 6 3

1 / PL 4 0 -1 275 3 21 / PL 5 0 -1 277 7 4

1 / PL 6 0 -1 277 2 1

1 / PL 7 0 -1 270 6 31 / PL 8 0 -1 268 4 2

1 / PL 9 0 -1 263 5 3

1 / PL 1 0 -1 261 7 3

1 / PL 1 0 -1 147 1 5

T

R rence N

M hiF

A. fu

4F

Am

5

Ba2

Ba3

EnEU/m3

air 1 / 177 ND ND 266 1 5 3 4 16 1 / 738 ND ND ND 1 6 1 6 253

1 / 377 ND ND 283 3 5 1 5 159

1 / 93 ND ND ND 8 5 4 5 66

1 / 722 ND 181 ND 2 6 1 6 706 1 / 358 ND ND 269 4 5 2 5 46

1 / 463 185 556 463 8 5 1 6 276

1 / 1 3 ND ND 93 1 6 4 5 184 1 / 100 ND ND ND 1 4 1 5 47

1 / 852 ND ND ND 2 6 4 5 453

1 / 510 ND ND ND 1 3 1 3 5170 Sal

N ( /m3)

…

31

onitori Results:

efeumber

mple mple description

g. me/task/process equi

ment

mple od

on Mins

esult g.m g.m

ll depleting

0001 06 : R R 6:52 1:25 .39 .78 0002 06 : WC 6:54 25 .35 .01

0003 06 : AP 6:53 1:25 .84 .85

0004 06 : AC 6:50 1:25 .77 .12 0005 06 : GM 6:48 1:25 .64 .29

0006 06 : CD 6:48 1:25 .36 .33

0007 06 : JP 6:55 1:25 .74 .79 0008 06 : CB 6:57 1:25 .91 .76

0014 06 : RW 7:02 1:25 .76 .24

0009 06 0: SA 7:04 1:25 .02 .95

00010 06 1: GD 8:58 1:25 0.41 .85

he exposures to bioaerosols are shown in the table below:

efeumber

esop lic ungi 25°C migatus

0°C ungi 40°C

ctino ycetes 5°C

cteria 5°C

cteria 7°C

dotoxin of

0001 06 .34x10 .65 x100002 06 .53 x10 .23 x10

0003 06 .31 x10 .94 x10

0004 06 .02 x10 .31 x10

0005 06 .00 x10 .68 x100006 06 .01 x10 .40 x10

0007 06 .33 x10 .13 x10

0008 06 .12x10 .03 x10 .24 x100014 06 .84 x10 .02 x10

0009 06 .52 x10 .24 x10

00010 06 .70 x10 .22 x10monella PCR screen all negative



Industry sector: Egg production


Location: Farm 2

Visit Date 13 Nov 2006

Activities on site: Producing eggs (caged birds over deep pit,) also grading & packing eggs in separate building.

A Cls

ctivities monitored: eaning out manure pit by specialist contractor, Also cleaning laying hed by resident farm staff

Materials involved (directly and indirectly) and contaminants: Faeces in quantity (several thousand tonnes), small proportion unused feed, micro-organisms, possibly feather &. dander, mites

Ventilation: Normal shed ventilation (Supply fans in roof blow air down through 2 floors of empty cages, venting through manure pit on ground floor, airflow in pit variable) Tractors have air-conditioned cabs but rear windows opened to allow vision when reversing along pit. Loaders have cab but no ventilation and are used with side door clipped open. Small skid-steer loader used with rotary brush has no cab.

Exposure controls in use: FFP2 RPE in use by contractor’s employees when in shed using front-end loader, but use variable/not rigorous. Farm staff also use FFP2 disposable respirators when brushing and scraping, also have ventilated helmet/visor for use when using compressed air for cleaning cages, conveyors and structures.

Observations: Each tractor driver reverses his trailer up the pit, then transfers to large loader to fill trailer. Each trailer takes approx 15 mins to fill, number of episodes each driver is in manure pit per day and interval between episodes depends on distance to tipping site. Loader operated with side window open. No forced cab ventilation apparent. Some areas of manure hot & steaming from decay. Simultaneous cleaning activity on upper floors contributes to dust level in pit. Rotary brush mounted on skid-steer loader used to sweep floor after bulk of manure removed (not monitored).

32

Monitoring Results:

Site R rence N

Satype

Sa(e.

na /

Saperi

Durati( s)

R(m -3)

8-hr TWA

(m -3) Far

8 / PS M 0 -0 70 61

8 / PS M 1 -1 133 2

C

8 / PS M 08: -0 13 2

68 / PS I 0 -0 14 3

8 / PS MP ( ) 0 -1 20 1

8 / SL h 0 -1 231 2

T

R rence N

MF

A. fu

s

F4

Am

5

Ba2

Ba3

EnEU/m3

air 8 / 1 4 ND ND ND 4 6 4 6 4014 8 / 9 3 ND ND ND 7 4 8 4 1263

8 / 1 4 ND ND 1 5 5 6 5 6 6192 8 / 4 4 ND ND 1 6 3 6 8 6 NR

8 / 1 4 ND ND 6 6 4 6 5 6 ND

8 / 1 3 ND ND 3 3 8 4 1 5 313

efeumber



mple od

on Min

esult g.m g.m

m Production staff. 854 06 W "blowing down" 8:02 9:12 7.93

9.04 856 06 W Brushing & scraping floors 0:15 2:28 .74

ontractors removing manure

855 06 P Mucking out 29 8:42 5.38

.22 857 06 M Mucking out 8:55 9:09 5.36

858 06 again Mucking out 9:40 0:00 7.25

859 06 alfway along manure pit 8:41 2:32 .39

he exposures to bioaerosols are shown in the table below:

efeumber

esophilic ungi 25°C migatu

40°C

ungi 0°C

ctino ycetes 5°C

cteria 5°C

cteria 7°C

dotoxin of

854 06 .00 x10 .36x10 .36 x10856 06 .02 x10 .03 x10 .57 x10

855 06 .35 x10 .77 x10 .12 x10 .08 x10857 06 .12 x10 .27 x10 .25 x10 .04 x10

858 06 .50 x10 .13 x10 .43 x10 .25x10

859 06 .65 x10 .61 x10 .97 x10 .13 x10

Salmonella PCR screen positive for 8855, 8858, 8859

ND = None Detected (LOD = 50 cfu/m3)

33


Industry sector: Egg production (free range)


Location: Farm 3

Visit Date 20th Nov 2006

Activities on site: Producing eggs Free range birds (Barn?) also grading & packing eggs in central section of building.

Activities monitored: Dismantling shed furniture by farm staff, removal of manure (contractor 1) and cleaning shed equipment (contractor 2)

Materials involved (directly and indirectly) and contaminants: Faeces from below roosting platform, litter from pecking areas, small proportion unused feed, possibly feather & dander, mites and micro-organisms..

Ventilation: Normal shed ventilation – inlet and extract fans in roof. Loaders have cabs but no ventilation and are used with side window clipped open.

Exposure controls in use: FFP2 RPE in use by contractor 1’s employees when in shed using front-end loader to remove litter. Resident farm workers use FFP2 when dismantling shed furniture

Observations: Farm employees dismantle all shed furniture except nest boxes along centre of shed. Double doors at end of shed open,

Each tractor driver parks trailer near shed door, then skid-steer loader to remove manure from shed and fill trailer. Each trailer takes approx 15 mins to fill, number of episodes each driver is in shed per day/interval between episodes depends on distance to tipping site. Small skid-steer loader with rotary brush used for final stage (not monitored.) Second contractor on site to clean shed furniture: employees soak “stippled” rubber mats in dilute detergent before pressure-washing them – unpleasant amount of spray bounces back at operative. No face or respiratory protection.

34

M

R rence N r

Satype

Sa(e.

na /

Saperi

Durati( )

R(m -

3)

8-hr TWA

(m -3) 0 / PS AW ( ) 1058 - 15 9 20 / PS AW ( ) 1154 – 14 7 2

0 / PS BL ( ) 1344 – 6 8 2

0 / SL Bbn

1012 - 252 4

0 / PL TL ( ) f e

1029 – 1230 –

182 1 1

0 / PL DL ( ) furn

1135 – 1232 -

115 1 8

0 / PL Bw -b 1429 - 56 1 1

T ero

R rence N

MF

A. fu

4

F4

Am

5

Ba2

Ba3

EnEU/m3

air 0 / 8 4 ND ND ND 1 7 6 6 494 0 / 3 3 1 x103 1 3 ND 6 6 2 7 332

0 / 3 3 ND ND ND 9 6 4 7 558

0 / 1 3 ND 298 2976 1 7 9 7 ND

0 / 6 3 139 139 ND 7 6 5 6 166

0 / 4 4 2 3 ND 2272 6 107 3 7 1190

0 / 5 3 ND ND ND 4 5 2 5 26

Sal

N ( /m3)

onitoring Results:

efeumbe



mple od

on Mins

esult g.m

g.m 9272 06 Contractor 1 mucking out 1115 4.7 3.7 9273 06 Contractor 1 mucking out 1208 9.9 0.0

9276 06 Contractor 1 mucking out 1350 0.3 0.1

9275 06 ackground, head height in shed eing mucked out, quarter of shed ot being dug.

1424 1.7

9271 06 Producer 2 dismantling shed urnitur

1146 1415

5.8 1.9

9274 06 Producer 2 dismantling shed iture

1146 1416

07.7 0.8

9277 06 ackline Ltd employee pressure ashing nest ox mats 1525 .6 .61

he exposures to bioa sols are shown in the table below:

efeumber


0°C

ungi 0°C

ctino ycetes 5°C

cteria 5°C

cteria 7°C

dotoxin of

9272 06 .09 x10 .60 x10 .18 x109273 06 .63 x10 .72 .72 x10 .07 x10 .29 x10

9276 06 .85x10 .04 x10 .00 x10

9275 06 .09 x10 .61 x10 .13 x10

9271 06 .27 x10 .22x10 .99 x10

9274 06 .54 x10 .27 x10 .41 x .93 x10

9277 06 .80 x10 .06 x10 .86 x10

monella PCR screen all positive except for 9277.


35


Industry sector: Egg Production


Location: Farm 2

Visit Date 01 December 2006

Activities on site: Producing eggs (caged birds over deep pit,) also grading & packing eggs in separate building.

Activities monitored: (Contractor 2) Repopulating (placing birds from transport modules into battery cages); Producer 2 employees performing routine house activities (inspection & various cleaning tasks) in adjacent houses; Contractor 3: haulier.

Materials involved (directly and indirectly) and contaminants:) Feathers, dander mites, meal and some faeces.

Ventilation: Large 3-storey shed: Supply fans in roof blow air down through 2 floors of cages venting through manure pit (ground floor).

Exposure controls in use: Resident workers wear FFP2 respirators when brushing, dusting, sweeping or using portable blowers. Populating cages: none.

Observations: The contractor’s staff reported that they were likely to spend a maximum of approximately 270 minutes in any working day actually transferring birds from the transit modules to cages.

36

M o : Sa

R rence N

Satype

Sa(e.

na /

Saperi

Durati( )

R(m -

3)

8-hr TWA

(m -3) Pemp R

9 / PL 1 1 -1 261 3 3

9 / PL 2 1 -1355 223 4 4

C ti9 / PL P 1 –1 129 9 5

9 / PL K 1 -1351 191 2 1

9 / PL CS f 1 -1 232 8 49 / PL LH 1049– 203 1 9

9 / PL D ( ) 1249- 81 6 3

C ( )

9 / PL J ldist 1 -1 97 2 1

T

R rence N

MF

A. fu

4

F4

Am

5

Bacfu/m3 2

Ba3

EnEU/m3

air 9 / 6 3 ND ND ND 1 6 3 5 25

9 / 1 3 ND 50 ND 1 6 4 4 249

9 / 8 3 ND ND ND 1 7 8 6 261 9 / 9 3 ND 50 ND 1 7 9 6 749

9 / 3 3 ND 450 ND 8 6 6 6 269

9657/ 1 4 ND ND ND 1 7 1 7 1441 9 / 6 3 ND ND ND 1 7 7 6 25

C ( )

9 / 794 ND ND ND 5 7 3 6 69

N ( /m3) ve

onit ring Resultsmple

efeumber



mple od

on Mins

esult g.m

g.m roducer 2’s

loyees: outine shed operations:

652 06 : EM, House 3 0.03 4.24 .94 .94

653 06 : DW, House 1 0.12 .03 .03

ontractor 2’s employees Repopula ng cages: 654 06 S, filling cages row 5 0.35 2.44 .42 .30

655 06 S filling row 4 0.40 3.77 3.37

656 06 illing row 3 0.40 4.32 .46 .76 657 06 filling row 2 14.12 6.89 .50

659 06 H filling Row 1 Least ventilation 14.10 .30 .54

ontractor 3’s employee Haulier

658 06 H: in trailer, operating scissors ift & ributing modules 2.25 4.02 .75 .03

he exposures to bioaerosols were as follows:

efeumber


0°C

ungi 0°C

ctino ycetes 5°C

cteria 5°C

cteria 7°C

dotoxin of

652 06 .00 x10 .38x10 .24 x10

653 06 .31 x10 .07 x10 .10 x10

654 06 .78 x10 .50 x10 .08 x10655 06 .56 x10 .50 x10 .19 x10

656 06 .03 x10 .41 x10 .25 x10

06 .10 x10 .72 x10 .64 x10659 06 .48 x10 .03 x10 .34 x10

ontractor 3’s employee Haulier

658 06 .13 x10 .12 x10

D = None Detected LOD = 50 cfu All Salmonella PCR screen negati

37


Industry sector: Broiler chicken production.

Employer: Producer 3 Ltd.

Location: Farm 1.

Visit Date 17/01/07

Activities on site: Raising birds from day-old to table weight.

Activities monitored: “Placing” day-old chicks.

Materials involved (directly and indirectly) and contaminants: Feather & dander, litter.

Ventilation: (switched off for welfare of chicks.)

Exposure controls in use: none

Observations: Specialist chick operators assisted by farm manager and staff from other farms gather to place chicks. Simply walk through sheds emptying trays of small birds onto prepared litter on floor. Some levelling of litter by hand/foot after birds have been placed.

38

M

R rence N

Satype

Sa(e.

na /

Saperi

Durati( )

R(m -

3)

8-hr TWA

(m -3)

3 / PS AG ( at ) t t 1204-1302 58 4 2

3 / PS P 1 -1 59 3 13 / PS RB ( ) 1 -1 58 3 1

3 / PS B 1 -1 56 3 1

3 / PS MR ( ) p 1 -1 57 5 2

3 / SS Bd

1 -1225 1 -11 -1

45 1

R rence N

MF

A. fu

4

F4

Am

5

Ba2

Bacte3

EnEU/m3

air 3 / 3 4 ND 2 3 9 4 1 6 4 5 NR 3 / 3 4 2 3 1 3 7 4 1 6 7 5 NR

3 / 3 4 1 3 2 3 7 4 1 6 1 5 319

3 / 2 4 ND 4 2x103 6 4 9 5 9 4 383

3 / 3 4 1 3 2 3 8 4 1 6 1 5 623 3 / 3 4 1 3 5 3 8 4 2 6 7 5 6

N ( /m3) N

onitoring Results:

efeumber



mple od

on Mins

esult g.m

g.m

09 07 Chick oper ive chick placing hrough hree sheds .70 .35

10 07 V chick placing ditto 2:05 3:04 .94 .97 11 07 relief mgr chick placing Ditto 2:05 3:03 .06 .53

12 07 G chick placing Ditto 2:06 3:02 .79 .90

13 07 Farm Mgr chick lacing Ditto 2:06 3:03 .48 .74

14 07 ackground halfway along houses uring chick placing

2:102.30 2.40 2.45 3.05

.83

efeumber


0°C

ungi 0°C

ctino ycetes 5°C

cteria 5°C

ria 7°C

dotoxin of

09 07 .84x10 .59x10 .31 x10 .84 x10 .01x1010 07 .31 x10 .12 x10 .27x10 .46 x10 .27x10 .71x10

11 07 .53 x10 .72 x10 .59x10 .80 x10 .61x10 .14x10

12 07 .90 x10 .0 .92 x10 .91x10 .11 x10

13 07 .51 x10 .75 x10 .19x10 .46 x10 .92x10 .07x1014 07 .06 x10 .67x10 .00x10 .94x10 .66x10 .61x10 9.9

D = None Detected LOD = 50 cfu R = No Result

39




Location: Farm 2.

Visit Date 17/1/07

Activities on site: Raising birds form day-old to table weight.

Activities monitored: Spreading litter in empty shed.

Materials involved (directly and indirectly) and contaminants: Chopped straw, treated with mould inhibitor.

Ventilation: Traditional houses, timber frame & boards. Fans located in side walls, air inlets in roof ridge. Some houses have fans one side only & ventilation openings in other.

Exposure controls in use: all fans in operation when spreading litter. No cabs on small tractors but drivers wear FFP2 RPE plus airstream ventilated helmets.

Observations: Litter delivered as shrink-wrapped bales, placed in shed by fork-lift truck, then spread by small tractor with tedder (“hay-turner”) attachment.

Monitoring Results:

Reference Sample Sample description Result 8-hrSample Duration (mg.m - TWANumber type (e.g. name/task/process/equipment period (Mins) 3) (mg.m -3)

315/07 PS SB Rough spreading litter (chopped 14:57-15:05 8 11.56 11.56 straw) 316/07 PS GP smoothing spread litter 15:05-15:45 40 15.69 15.69

317/07 PS CH forking litter to walls 15:47-16:00 13 3.65 3.65

318/07 SL Background halfway along house 15:00-16:05 65 7.12 during litter laying

40

R rence N

MF

A. fu

4

F4

Am

5

Ba2

Ba3

EnEU/m3

air 3 / 3 5 ND - 9 3 1 7 1 5 224

3 / 6. 5 2 3 5 3 1 5 2 7 6 5 5

3 / 4 4 ND - ND 5 5 1 3 23 / 6 5 ND 769 5 3 9 5 6 5 NR

N ( /m3) N

efeumber


0°C

ungi 0°C

ctino ycetes 5°C

cteria 5°C

cteria 7°C

dotoxin of

15 07 .28x10 .38x10 .14 x10 .78x10

16 07 00x10 .50 x10 .00x10 .28x10 .00 x10 .00x10 5.5

17 07 .23 x10 .54x10 .92 x10 0.9 18 07 .00x10 .77x10 .38x10 .00x10

D = None Detected LOD = 50 cfu R = No Result

41




Location: Farm 3.

Visit Date 18/1/07


Activities monitored: Contractor catching birds

Materials involved (directly and indirectly) and contaminants: Feather & dander, chopped straw, treated with mould inhibitor, faeces, mites microbes .

Ventilation: As Farm 2 – Visit 9.

Exposure controls in use: FFP3 in use by contractors

Observations: lighting low to subdue birds (reduces flapping.

Monitoring Results:

Reference Sample Sample description Sample Duration Result 8-hr (e.g. TWA period (Mins) (mg.m -3) (mg.m -3)Number type name/task/process/equipment

319/07 PS 18/01/2007 KA Catching 10:20-10:35 15 6.17 4.62 320/07 PS GC loading & catching 10:20-10:35 fail

321/07 PS JD catching 10:20-10:35 15 6.32 4.74

322/07 PS AR Catching 10:20-10:35 15 2.83 2.13

Reference Number

Mesophilic Fungi 25°C

A. fumigatus

40°C

Fungi 40°C

Actino mycetes

55°C

Bacteria 25°C

Bacteria 37°C

Endotoxin EU/m3 of

air 319/07 5.00x103 ND ND ND 4.17x106 1.80x106 30.5 320/07 2.50x103 ND ND ND 1.66x106 1.28x106 12.2

321/07 6.84x103 ND ND ND 1.50 x107 7.18x106 30.7

322/07 6.67 x103 ND ND ND 4.23x106 3.47x106 22.9

ND = None Detected (LOD = 50 cfu/m3)

42




Location: Farm 3.

Visit Date 18/1/07


Activities monitored: Contractor’s staff removing manure from broiler shed.

Materials involved (directly and indirectly) and contaminants: (Original chopped straw, treated with mould inhibitor) faeces, dander and feather, mites, waste feed.

Ventilation: As Farm 2 – Visit 9

Exposure Controls: None

Observations: Litter fairly dry. Cabless Bobcat skid-steer loader used to move the waste from shed interior to elevator, which conveys it up into deep articulated lorries for transport to power station. Wind blows large amounts around yard and back over Bobcat driver. Portable blower used to remove dust deposits from shed beams etc.

Reference Sample Sample description Sample Duration Result 8-hr TWA(e.g. period (Mins) (mg.m -3) (mg.m -3)

Number type name/task/process/equipment 324/07 SL Mucking out centre of shed 11:05-12:20 75 2.25

325/07 PL GG Bobcat driver & loading 10:46-12:13 87 28.50 28.50 elevator 326/07 PL PC Gang supervisor on Bobcat 10:47-12:17 90 14.81 14.81

327/07 PL WT Sweeping (mechanical?) 10:46-12:21 95 33.13 33.13

Reference Number

Mesophilic Fungi 25°C

A. fumigatus

40°C

Fungi 40°C

Actino mycetes

55°C

Bacteria 25°C

Bacteri a 37°C

Endotoxin EU/m3 of

air

324/07 2.67x104 ND ND 635 1.47x106 1.40x106 ND

325/07 1.36 x104 ND ND 1.04x104 2.00x108 1.23x108 NR

326/07 1.78 x104 ND 278 556 1.31x108 1.40x108 NR

327/07 1.63 x104 ND ND 2.37x103 4.13 x107 3.84 x107 1140 ND = None Detected (LOD = 50 cfu/m3) NR = No Result

43

1

2

3

4

5

6

7

8

9

1

2

3

4

5

6

7

8

APPENDIX B: PHOTOGRAPHS Photograph : Laying litter - transferring wood “shreds” into shed

Photograph : Laying litter –cleaning/blowing final wood “shreds” into shed

Photograph : Spreading litter in shed (1)

Photograph : Spreading litter in shed (2)

Photograph Spreading litter in shed: alternative equipment

Photograph : Mechanised laying of straw litter

Photograph : Routine manual addition of litter during duck-rearing

Photograph : Populating house with day-old chicks

Photograph Populating battery house

Photograph 10: Populating free range house

Photograph 1 : Routine flock management- vaccinating by hand

Photograph 1 : Routine housework - dusting

Photograph 1 : Routine housework - blowing

Photograph 1 : Routine housework - sweeping

Photograph 1 : Catching ducks

Photograph 1 : Depopulating broiler house

Photograph 1 : Depopulating battery house – carrying hens

Photograph 1 : Free-range house showing shed furniture, all of which is disassembled and removed to allow manure removal.

Photograph 19: Free range house before manure removal

Photograph 20: Cleaning open-floor (rearing) shed – blowing litter from base of stanchion

1Photograph 2 : Manure removal – broiler house

2Photograph 2 : Manure removal – free-range system (1)



5Photograph 2 : Battery house manure “pit” before removal

6Photograph 2 : Manure removal & transport (common equipment)

7Photograph 2 : Cleaning – Powered rotary brush (common equipment)

8Photograph 2 : Compressed airline used to clean fans and fan casings

9Photograph 2 : Free range house: Contractor cleaning shed furniture

Photograph 30: Broiler house: Contractor cleaning shed furniture

44

Photograph 1: Laying litter - transferring wood “shreds” into shed

Photograph 2: Laying litter –cleaning/blowing final wood “shreds” into shed

45

Photograph 3: Spreading litter in shed (1)

Photograph 4: Spreading litter in shed (2)

46

Photograph 5 Spreading litter in shed: alternative equipment

Photograph 6: Mechanised laying of straw litter

47

Photograph 7: Routine manual addition of litter during duck-rearing

Photograph 8: Populating house with day-old chicks

48

Photograph 9 Populating battery house

Photograph 10: Populating free range house

49

Photograph 11: Routine flock management- vaccinating by hand

50

Photograph 12: Routine housework – dusting

Photograph 13: Routine housework - blowing 51

Photograph 14: Routine housework – sweeping

Photograph 15: Catching ducks

52

Photograph 16: Depopulating broiler house

Photograph 17: Depopulating battery house – carrying hens

53

Photograph 18: Free-range house showing shed furniture, all of which is disassembled and removed to allow manure removal.

Photograph 19: Free range house before manure removal 54

Photograph: 20: Cleaning open-floor (rearing) shed – blowing litter from base of stanchion

Photograph 21: Manure removal – broiler house

55

Photograph 22: Manure removal – free-range system (1)


56


Photograph 25: Battery house manure “pit” before removal 57

Photograph 26: Manure removal & transport (common equipment)

Photograph 27: Cleaning – Powered rotary brush (common equipment) 58

Photograph 28: Compressed airline used to clean fans and fan casings

Photograph 29: Free range house: Contractor cleaning shed furniture

59

Photograph 30: Broiler house: Contractor cleaning shed furniture

60

61

9 REFERENCES

Crook B, Elms J, Hnat K (2003). Review: Dusts and asthmagens in agriculture related to work task. HSL Internal Report for project JS2002926.

Donham KJ, Leistikow B, Merchant J, Leonard S. (1990) Assessment of United-States Poultry Worker Respiratory Risks. Am J Ind Med; 17: 73-74.

Donham KJ, Cumro D, Reynolds SJ Merchant JA. (2000) Dose-response relationships between occupational aerosol exposures and cross-shift declines of lung function in poultry workers: Recommendations for exposure limits. J Occup Env Med; 42: 260-269.

HSE (2000). MDHS 14/3; General methods for sampling and gravimetric analysis of respirable and inhalable dust. Available at http://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs14-3.pdf

HSE (2005) EH40/2005 Workplace exposure limits, ISBN 0-7176-2977-5, as amended 2007 (http://www.hse.gov.uk/coshh/table1.pdf)

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Liebers V, Raulf-Heimsoth M, Linsel G, Goldscheid N, Düser M, Stubel H, Brüning T(2007). Evaluation of quantification methods of occupational endotoxin exposure. J Toxicol Environ Health A. 70:1798-805.

Morris PD, Lenhart SW, Service WS. (1991) Respiratory symptoms and pulmonary function in chicken catchers in poultry confinement units. Am J Ind Med; 19: 195-204.

Nielsen BH, Breum NO. (1995) Exposure to Air Contaminants in Chicken Catching. Am Ind Hyg Ass J; 56: 804-808.

ONS (2007) Office of National Statistics: UK Business: Activity, Size and Location – 2006

Radon K, Danuser B, Iversen M, Jörres R, Monso E, Opravil U, Weber C, Donham KJ, Nowak D. (2001) Respiratory symptoms in European animal farmers. Eur Resp J; 17: 747-754.

Radon K, Danuser B, Iversen M, Monso E, Weber C, Hartung J, Donham KJ, Palmgren U, Nowak D (2002). Air contaminants in different European farming environments. Ann Agric Environ Med, 9, 1–48.

Reed S, Quartararo M, Kift R, Davidson M, Mulley R. (2006). Respiratory Illness in Farmers; Dust and bioaerosols exposures in animal handling facilities. Report for the Rural Industries Research and Development Corporation, RIRDC Publication No 06/107. Available at http://www.rirdc.gov.au

Reynolds SJ, Milton DK, Heederik D, Thorne PS, Donham KJ, Croteau EA, Kelly KM, Douwes J, Lewis D, Whitmer M, Connaughton I, Koch S, Malmberg P, Larsson BM, Deddens J, Saraf A, Larsson L. (2005). Interlaboratory evaluation of endotoxin analyses in agricultural dusts-comparison of LAL assay and mass spectrometry. J Environ Monit. 7: 1371-7.

Reynolds SJ, Thorne PS, Donham KJ, Croteau EA, Kelly KM, Lewis D, Whitmer M, Heederik DJ, Douwes J, Connaughton I, Koch S, Malmberg P, Larsson BM, Milton DK (2002). Comparison of endotoxin assays using agricultural dusts. AIHA J;63: 430-8.

Rylander R, Carvalheiro MF. (2006) Airways inflammation among workers in poultry houses. Int Arch Occup Environ Hlth; 79: 487-490.

Sigsgaard T, Bonefeld-Jorgensen EC, Hoffmann HJ, Bonlokke J, Krüger T. (2005). Microbial cell wall agents as an occupational hazard. Toxicol Appl Pharmacol; 207: 310-319.

Swan JRM, Kelsey A, Crook B, Gilbert EJ (2003) Occupational and environmental exposure to bioaerosols from composts and potential health effects - A critical review of published data. HSE Research Report 130. Available at http://www.hse.gov.uk/research/rrpdf/rr130.pdf

Thelin A, Tegler O, Rylander R. (1984) Lung Reactions During Poultry Handling Related to Dust and Bacterial-Endotoxin Levels. Eur J Resp Dis; 65: 266-271.

Published by the Health and Safety Executive 09/08

Exposure to dust and bioaerosols in poultry farmingSummary of observations and data

Health and Safety Executive

RR655

www.hse.gov.uk


The UK poultry industry (mainly the production of hens’ eggs and chicken, turkey and duck meats) involves a range of activities including laying litter, populating with young birds, depopulating (reducing bird density during growth or removing at the end of the cycle), litter/manure removal, cleaning houses after depopulation and routine ‘crop maintenance’ and housework. The objective of this study was to measure workers’ exposure to airborne dust and bioaerosols (micro-organisms and their products) associated with these tasks in a representative cross-section of commercial poultry production.


This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.

exposure to dust and bioaerosols in poultry farming ... · pdf filein poultry farming summary...

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