PollutionPreventionforHospitals &MedicalFacilitiesRegional Water QualityControl PlantOperated by the City of Palo Altofor the communities of East Palo AltoLOS Altos. Los Altos Hills, MountainView. Palo Alto. and Stanford

Medical Facilities:Part of the Solution toWater Pollution

W orking closely with local hospitals, the Regional

Water Quality Control Plant (RWQCP) has

developed these pollution prevention guidelines

to minimize pollutant loadings to the sewer from hospitals and

other medical facilities. Pollutants of concern include:

These contaminants are especially problematic for the

Regional Water Quality Control Plant due to new, extremely

stringent discharge limits for south San Francisco Bay.

This is why source reduction-reducing pollution to the

greatest extent possible before wastes enter the sewer-plays

a central role in our efforts to protect water quality. With care

and foresight, hospitals and medical facilities can significantly

reduce the amounts of these pollutants in waste disposed to

sinks or other drains.

While the mass of pollutants from medical facilities can

be very large, hospital waste is often greatly diluted with

domestic wastewater. In addition to source reduction, water

conservation is also an important goal of a comprehensive

water quality protection program. Most hospitals and medical

facilities can reduce water consumption in many ways.

A healthy Bay requires our best efforts in both pollutant

source reduction and water conservation.

Please read through these materials and share them with

your colleagues. If you have any questions about these

pollution prevention guidelines or any of the Regional Water

Quality Control Plant’s water quality protection programs,

call 329-2598.

Radiology

Problem substances include silver (in spentprocessor solutions), chromium (in developercleaners), and selenium (in some toners).

Since x-ray film has an especially high silver content,spent fixer from medical X-ray developing operationshas been a major source of silver for the wastewatertreatment plant.

In 1991 RWQCP service area communities adopteda Silver Reduction Ordinance that requires all com-mercial and industrial facilities, including hospitalsand medical offices, to treat silvercontaining wastesto remove the silver or have them hauled off-site ashazardous wastes. Most hospitals now have theirwastes hauled off-site for recycling.

X-ray processing can use more water than almostany other, non-domestic operation in a medicalfacility.

u In a large facility, centralized treatment of spentfixer reduces the amount of sampling requiredas well as the number of systems to be main-tained-easily offsetting the increased effortrequired to collect and consolidate the waste.

u If processors are cleaned with a chromic acidsolution such as Kodak’s Liquid DeveloperSystem Cleaner, spent cleaning solutions andrinsewater must also be disposed of as ahazardous waste. They must not be mixed withspent fix from which silver will be reclaimed.

u Spent photochemicals containing seleniumsuch as Kodak Rapid Selenium Toner must bedisposed of as hazardous wastes. Never pourselenium-bearing solutions down a sink ordrain!

u Newer, well-maintained equipment generallyuses less water and smaller volumes of chemi-cals, with reduced carry-over of silver-bearingfixer into the rinse water.

For more information about the RWQCP’sSilver Reduction Ordinance requirements,call 329-2598.

Physicians

Problem substances: mercury, selenium,and zinc.

Because mercury is acutely toxic in extremely smallamounts, and because it is one of the metals thatconventional wastewater treatment plants cannotcompletely remove from sewage, mercury’s presencein wastewater from medical offices and hospitals is aserious problem for the health of the Bay. Mercury isunlikely to be eliminated from wastewater whilemedical facilities continue to use equipment contain-ing mercury.

u Instruct staff to use the available alternativesto mercury thermometers, such as digitalthermometers, electronic sensors, andtemperature strips.

u Until you have eliminated all mercury-containing equipment from your office:

Make sure mercury spill cleanup kits arereadily available in all areas where mercury-containing equipment is used.

Clean up all mercury spills properly andcompletely.

Do not send mercury thermometers homewith patients.

When possible, substitute Anderson tubesfor Canter tubes. The Anderson tubecontains no mercury and can be an accept-able substitute.

Physicians’ prescription practices can help improvewater quality in the Bay. When patients use dandruffshampoos containing selenium, this extremely toxicheavy metal is rinsed to the sewer. Wastewater treat-ment cannot remove enough selenium to protect theBay. Zinc ointments prescribed for diaper rash andother dermatology applications contribute to waterpollution in similar ways, entering the sewer whenbabies are bathed or when the diapers are washed.

u Whenever possible, prescribe non-metallicshampoos and medications.

u Evaluate drug ingredients for metals, andprescribe non-metallic alternatives whenfeasible.

Hemodialysis Radiation Therapy

Problem substances include formaldehydeand disinfectants.

Disinfection of dialysis equipment and the associatedreverse osmosis (RO) systems used to purify dialysiswater can cause water pollution problems if formalde-hyde-based disinfectants are used and discharged tothe sanitary sewer.

u A solution of peracetic acid, acetic acid andhydrogen peroxide (such as Renalin or Actril)can de substituted for formaldehyde-baseddisinfectants. These products yield decomposi-tion products that are easily handled by awastewater treatment plant’s biological treat-ment processes. Since formaldehyde is asuspected carcinogen, use of a substitute mayhave other significant benefits for both patientsand technicians.

u The RO system used for water filtration mayalso be disinfected with similar products. ROunits can be made compatible with par-aceticacid disinfectants through pretreatment toremove any iron, which may react with theoxidizing solution and form holes in themembrane. (Some rubber or metal systemcomponents may also need to be replaced.)

u Use of peracetic acid disinfectants with thesmall membrane cartridges and in the dialysisequipment itself can also reduce the volumeof hazardous waste generated. Older machinesmust be modified to use per-acetic acid disinfec-tants but newer machines should be compat-ible. Equipment that can be heat-disinfectedmay be available in the near future.

u Any dialysis unit that is still using formaldehydefor disinfection should collect all waste solu-tions and dispose of them as hazardous waste.

Problems include wastes containing lead,cadmium, other metals, and low-levelradioactive waste.

Lead ShieldingLead shielding used to protect patients during radia-tion therapy is normally either machined from leadblocks or poured in molds.

u All machining waste (from sawing, filing, andwashing operations) must be collected anddisposed of as hazardous waste.

u Molded shields are made from low-melting-temperature lead alloys such as Cerrabend,which contains bismuth, tin, and cadmium.Because of the metal content, any wastesfrom washing, filing, or other working of thecasts should be collected and disposed of ashazardous waste.

Radioactive WasteRadioactive waste results from the use of tracersand other radioactive diagnostic and treatmentprocedures.

u Each facility’s radiation safety officer mustfollow all Nuclear Regulatory Commission(NRC) regulations concerning the disposaland storage of radioactive materials and waste.Limited amounts of some substances areacceptable for disposal in the sanitary sewer.In California the radiation program is handledby the Department of Health Services (DHS),Radiological Health Branch.

u For more information about applicableregulations, call DHS at (916) 323-2759.

Clean WaterPractices for

Medical FacilityAdministration

Effective planning for water quality protectioninvolves numerous departments andoperations.

Personnel/ManagementStructure

u All large and small medical facilities shouldhave at least one employee with specificresponsibility for developing and implementingenvironmental programs. In hospitals and otherlarge facilities this may be a full-time job for oneor more persons.

u An environmental coordinating committeethat includes interested members of affecteddepartments or groups can provide invaluablefeedback and information on many programsand strategies that cross departmentalboundaries.

u Internal environmental audits should be conducted regularly by in-house staff orconsultants.

Trainingu Personnel in all departments should be trained

for awareness of their roles in pollution preven-tion and waste minimization.

u Environmental concerns should be prominentlyfeatured in training for new employees, annualsafety training, and other related meetings.Specific requirements for work groups such asnursing, housekeeping, laboratory, and radiol-ogy should be addressed regularly.

u Posters, fliers, and labeling should be used toremind employees about pollution preventionstrategies. For example, post signs above sinks

stating that hazardous chemicals must not bedisposed to the sewer. Label instruments andprocesses that use problem materials so thatthe user is aware of his/her responsibilities.

Procurement/Central Receiving

u When ordering materials or equipment,consider pollution prevention and potentialproblems for waste disposal.

u A centralized receiving department can imple-ment proper labeling of hazardous materialswith use and disposal cautions, and also initiatea tracking program for problem substances.

u Careful inventory control using a first-in/first-used scheme can reduce excess purchas-ing and unnecessary duplication in variousinventories, as well as the amount of outdatedor unneeded materials which must be disposedof as hazardous waste.

ContractingThe Regional Water Quality Control Plant (RWQCP)recommends incorporating environmental protectionstandards into maintenance and construction con-tracts whenever possible.

u Construction contractors should protect stormdrams from dirt, saw-cut slurry, and spills of allkinds. Paints and solvents must not be dis-charged to sewers or storm drains. Make surecontractors clean up their materials and workareas at the end of the day, especially duringwet weather. Sample contract language anddetailed best management practice informationfor different types of construction are availablefrom the RWQCP

u Make sure cooling system maintenance firmsuse only those treatment chemicals allowedin the Sewer Use Ordinance. Wastewater andcleaning solutions must meet dischargestandards.

u Require grounds maintenance, landscaping,and cleaning firms to eliminate storm draindischarges and protect paved surfaces frompotential runoff contamination.

Housekeeping

Problem materials include phenolicdisinfectants and infectious waste.

Phenolic DisinfectantsHousekeeping includes normal cleaning operationsas well as disinfection of critical areas. Many hospitalshave found that phenolics, which are hazardousmaterials that must be regulated if discharged to thesewer, are not necessary for adequate disinfection.Phenolic compounds are toxic and may bioaccumulatein the environment; a wastewater treatment plant%biological treatment system may not completelyremove them from sewage.

u Eliminate use of phenolic disinfectantswherever possible. Consider substitutingquaternary amine disinfectants, which havebeen shown by many infection controldepartments to be suitable. (Quarternaryamine disinfectants are also hazardous, butpose fewer problems for the wastewatertreatment plant)

u If phenols are used, keep concentrations to theminimum recommended by the manufacturer.Use pumps or auto-feed systems that supply theappropriate dose when preparing a solution;prepare only the amount to be used. Measuresmay need to be taken to ensure that personneldo not override these controls in an effort tomake the solutions stronger than necessary.

u Store both types of concentrated disinfectants(and all hazardous chemicals) in secondarycontainment to avoid spills.

u Never discharge concentrated disinfectantsolutions to the sanitary sewer.

Infectious Waste

both of these problems is to minimize the amount ofinfectious waste generated throughout the hospital ormedical facility.

u Educate all employees about the nature ofappropriate red bag waste and the cost of itsdisposal. A large portion of this waste is oftennon-infectious paper products or other officetrash. Workers may place these materials in theinfectious waste receptacle because it is moreconvenient, or because the user is unaware thatthese items can be discarded as normal trash.

u Encourage the segregation of non-infectiouswaste. Inclusion of such items as batteries,X-ray film, electronics, thermometers, hazard-ous waste, and packaging (often with metal-containing pigments) with infectious wastecontributes significantly to metals loading inthe waste stream.

Infectious or ‘red bag” waste is usually incinerated,landfilled, or recycled after sterilization. In any case,the cost of infectious waste disposal is high. Waste-water produced by incinerator scrubbers can containsignificant amounts of metals. One partial solution to

Central Sterilization

Problem substances include cold sterilants andcaustic cleaners.

Of the wide range of sterilizing processes used byhospitals and other medical facilities, those of mostconcern to the Regional Water Quality Control Plant(RWQCP) are certain cold sterilants (glutaraldehyde,formaldehyde, and phenols), and institutional dish-washers using caustic cleaners. Other processes(ethylene oxide chambers, for instance) may be ofinterest to agencies concerned with air quality.

u Cold sterilizing solutions containing glutaralde-hyde or formaldehyde have been commonlydischarged to the sanitary sewer in the pastUse of these chemicals should be minimized oreliminated where possible. Spent solutionsmust be treated as hazardous waste using aneutralizer such as Formalex, or collected andproperly disposed. Activated glutaraldehydesolutions lose their toxicity when held for aperiod of time (usually 14 to 21 days). After thattime they may be acceptable for discharge tothe Regional Water Quality Control Plant, aslong as all other laws and regulations aresatisfied. Alternative sterilization methods arenearly always possible.

u Sonic sterilization may be used alone or inconjunction with solutions. This alternativemay be used with less toxic solutions thatdon’t pose a threat to the environment ifdisposed to the sanitary sewer.

u Alternative liquid sterilants include, amongothers, formulations of per-acetic acid, aceticacid and hydrogen peroxide (Renalin, Actril,etc.). These products are currently being usedprimarily on dialysis equipment, but may haveother uses. Chemicals in the spent solutions donot pose a problem for the RWQCP if they aredisposed of properly.

u Steam sterilization (autoclaving) produces littleor no chemical waste. However, without coolingwater recirculators or sensors to keep coolingwater use to a minimum, autoclaves can be one

of the hospital’s largest water users. Water-saving modifications to autoclaves easily payfor themselves with savings from water andsewer bills.

u Large industrial-type dishwashers may be usedfor sterilization as well as cleaning. Thesecommonly use hot water, steam, and causticcleaners. Water and chemical use should beminimized where practical. Concentratedcaustic cleaning chemicals should be stored insecondary containment to prevent concentratedspills from reaching the sanitary sewer.

u The sterilizing gas ethylene oxide (EtO) isnormally applied to equipment held in a steriliz-ing chamber. Use of EtO requires air emissionscontrol devices. The wastewater from emissioncontrol scrubbers that convert the EtO to anethylene glycol solution may be discharged tothe sanitary sewer.

u Other proposed alternative sterilization meth-ods include gas phase hydrogen peroxide,electron beam, gas plasma, and microwave.Although none of these appear to pose signifi-cant risks related to the sanitary sewer orwastewater disposal, they are not yet widelyavailable.

MaterialsManagement

Problem substances: hazardous materials,hazardous wastes, cleaning products, and allother chemicalsu All hazardous materials and wastes should be

labeled and stored according to federal, state,and local regulatory requirements. Chemicalstorage practices should follow the “bestmanagement practices” detailed in Laboratories:Best Management Practices for Water QualityProtection, available from the Regional WaterQuality Control Plant, and other publicationsincluding Fire Department regulations.

u It is essential to segregate noncompatiblematerials and provide secondary containment,which keeps spilled materials from enteringadmin.

u Floor drains should be eliminated in all areaswhere hazardous materials are handled orstored.

u Material Safety Data Sheets (MSDSs) should bereadily available for all of the materials used,and accessible to all staff. Each product’s useand its MSDS should be evaluated regularlyto ensure that the material is handled properlyand that alternative, less toxic chemicals areconsidered when possible. However, it isimportant to remember that MSDSs do notlist all ingredients. Some substances that posesignificant environmental problems (e.g. copperor zinc) may be omitted from MSDSs orsupplier literature. If you suspect that a chemi-cal may contain a hazardous constituent, checkwith the supplier. If there is any doubt, disposeof spent materials as hazardous waste until thequestion has been resolved.

u Label containers, instruments, and processesthat hold or use problem materials so that eachuser is aware of his or her responsibility forproper use and disposal.

u Keep bottled chemicals in secured storage, onlow shelves (never over sinks) or in storagecabinets with latching doors. Follow FireDepartment regulations.

u Prevent bottle breakage and spills by usingtrays with lips or other specialized carryingcontainers to transfer chemical bottles betweenstorage areas and labs.

PharmacyProblem substances include silver, selenium,zinc, and other metals.Most pharmacies dispense commercially preparedmedicines rather than compounding prescriptionson site. Medical products may contain significantamounts of metals that should not reach the sewer.

u If pharmacists at your facility have occasion torecommend over-the-counter medications topatients, they should consider suggesting less-toxic substitutes for hazardous formulations.Some products to avoid include selenium-con-taining dandruff shampoos and zinc ointments.

Silver Solutions andOintments

Concentrated silver nitrate solutions are prepared inpharmacies for use to treat burns. Solutions withsilver concentrations above 5 ppm must be collectedand disposed of as hazardous waste.

Chemicals Storageand Disposal

u Pharmacy personnel should inventory chemicalstores periodically and properly dispose of allchemicals that are no longer used, includingexpired medicines.

u No pollutant-containing products should bediscarded to the sanitary sewer. Substancesto be aware of include hazardous wastes andall products containing silver, cadmium, chromium, copper, cyanide, lead, mercury, nickel,selenium and zinc.

u Be sure that chemical storage practices followthe “best management practices” detailed inLaboratories: Best Management Practices forWater Quality Protection (available from theRegional Water Quality Control Plant) and inother publications including Fire Departmentregulations.

u Keep bottled chemicals in secured storage, onlow shelves (never over sinks) or in storagecabinets with latching doors. Follow FireDepartment regulations.

u Store acids separately from bases, and flam-mables separately from oxidizers.

u Make sure all chemical containers are clearlylabeled.

u Provide secondary containment for all hazard-ous materials and waste storage.

u Prevent bottle breakage and spills by usingtrays with lips or other specialized carryingcontainers when transferring chemical bottlesbetween storage areas and labs.

Compoundingu Any compounding done in the pharmacy should

also follow the guidelines in Laboratories: BestManagement Practices for Water QualityProtection.

u Prepare only minimum amounts and collectall waste.

u Pour or mix liquid chemicals within a tray orother secondary containment, so that spills willnot reach a drain.

u When compounding powders, clean up “dust”using dry cleanup methods as soon as possible,so that chemicals will not reach the sewerduring routine wet cleaning operations.

Nursing andPatient Care

Infectious Waste/Incinerators

Problem substances include mercury,phenolics, and pharmaceutical products.

While most of the wastewater sent to the sanitarysewer from patient care areas is very similar tohousehold wastewater, potential concerns includedisinfection supplies, medicines and otherpharmaceutical products, and spills from mercury-containing equipment such as thermometers andblood pressure cuffs.

Because mercury is acutely toxic in extremelysmall amounts, and because it is one of the metalsthat conventional wastewater treatment plants cannotcompletely remove from sewage, mercury’s presencein medical facility wastewater is a serious problem forthe health of the Bay. Mercury is unlikely to beeliminated from wastewater while medical facilitiescontinue to use equipment containing mercury.

u Use some of the available alternatives tomercury thermometers, such as electronicsensors, digital thermometers, and temper-ature strips.

u Mercury spill cleanup kits should be availablein all areas where mercury-containing equipment, such as thermometers and blood pres-sure cuffs, is used.

u Make sure the individual designated by theenvironmental health and safety department -cleans up all mercury spills. If your facility doesnot have such a person, instruct all employeesin the proper handling and management(usually recycling) of mercury

u Do not send mercury thermometers homewith patients.

u Blood pressure cuffs with electronic sensorsare available. Replace the mercurycontainingdevices where appropriate.

u When possible, substitute Anderson tubes forCanter tubes. The Anderson tube contains nomercury and can be an acceptable substitute.

Infectious or “red bag” waste is usually landfilled orrecycled after sterilization, or incinerated. In any case,the cost of infectious waste disposal is high. Waste-water produced by incinerator scrubbers can containsignificant amounts of metals. One partial solution toboth of these problems is to minimize the amount ofinfectious waste generated throughout the hospitalor medical facility

u Educate all employees about the nature ofappropriate red bag waste and the cost of itsdisposal. A large portion of this waste is oftennon-infectious paper products or other officetrash. Workers may place these materials in theinfectious waste receptacle because it is moreconvenient, or because the user is unaware thatthese items can be discarded as normal trash.

u Encourage the segregation of non-infectiouswaste. Inclusion of such items as batteries,X-ray film, electronics, thermometers, hazard-ous waste, and packaging (often with metalcontaining pigments) with infectious wastecontributes significantly to metals loading inthe waste stream.

Laboratories

The numerous laboratory operations in hospitalsand other medical facilities are significant potentialsources of pollutant discharges to the sanitary sewer.All laboratories should implement the basic proce-dures outlined in Laboratories: Best ManagementPractices for Water Quality Protection.

So many lab waste solutions contain significantconcentrations of metals and other chemicals thatit would be practically impossible to list all of thereagents and test kits containing pollutants ofconcern that could be used in your facility.

u Laboratory personnel must know the constitu-ents of each reagent used, as well as the properdisposal method. Products that are not suitablefor discharge to the sewer must be collected fordisposal as hazardous waste.

u Managers should review the chemical contentsof all reagents periodically In many instances aproblem solution can be used in smallerquantities, or replaced with less harmfulalternatives.

u When determining whether a waste solutionmeets discharge concentration limits or re-quires disposal as hazardous waste, rememberthat the solution to pollution is not dilution!

u Segregate wastes appropriately-for bothstorage and disposal-according to yourfacility’s health and safety guidelines or youragreement with a hazardous waste hauler.

In this booklet. . .

Chemistry LabsProblem substances include mercury, copper,chromium, and cyanide.These days most lab chemistry analyses are run onautomated systems or other instrumentation that usevery small volumes of samples and reagents. Advan-tages of such systems over “test tube scale” proce-dures include waste minimization as well as increasedproductivity. With several methods usually availablefor any one parameter, careful choice of methods canreduce or eliminate many waste problems.

u Lab managers and analysts should be aware ofthe available options and choose the one thatproduces the best results with the least amountof waste.

Hematology LabsProblem substances include cyanide,formaldehyde, chloroform and other solvents,xylenes, mercury, copper, chromium, zinc, andlow-level radioactive wastes.u Cyanide-containing cell lysing solutions are

common reagents in many blood tests. Cellsorter/counting instruments using thesesolutions generate a waste solution that is justbelow the hospital’s discharge limit for cyanideand acceptable for discharge.

u The manual iron-cyanide test yields a concen-trated cyanide solution that should be collected,stored in secondary containment segregatedfrom all acidic solutions, and disposed of ashazardous waste.

Chemistry andHematology Labs

Several other waste streams common to bothhematology and chemistry labs should be reviewedand possibly collected for disposal:

u Bouin’s solution, used for washing bonemarrow cells and as a preservative, containsformaldehyde. Concentrated formaldehydesolutions like Bouin’s solution are hazardouswastes. They must be collected and disposed of

properly whenever concentrations exceed thehospital’s discharge limit.

u Ail waste solvents should be collected fordisposal as hazardous waste. These includechloroform and methylene chloride (used toextract blood and urine samples for GC analy-sis), as well as solvents used for TLC analysis.Minimize extraction sample sizes to reducethe quantity of solvents used. Investigate lesshazardous solvents and methods.

u Waste from atomic absorption (AA) standardsfor heavy metals should be collected anddisposed of as hazardous waste. Producestandards only as needed.

u Minimize use of xylenes for extractions andbe sure to collect any waste. Terpene-basedsolvents (Hemo-D) may be substituted forxylenes used for slide cleaning in someapplications.

u Analysis of chloride by ion-selective electrode(ISE) is preferable to the calorimetric method.Calorimetric analysis uses a mercury reagent,and generates a highly toxic waste stream forwhich collection and disposal may be difficultand expensive.

u All solutions from the titrametric methodcommonly used for analysis of chloride insweat are hazardous and must be collected fordisposal as hazardous waste.

u At least one albumin method uses a highlyconcentrated chromium reagent. This solutionexceeds the hospital’s discharge limit forchromium, and should be collected for disposalas hazardous waste.

u At least one total protein method uses a concen-trated copper reagent. The solution exceeds thehospital’s discharge limit for copper, and shouldbe collected for disposal as hazardous waste.

u At least one preservative for stool samplescontains a concentrated copper solution. Thisshould not be discharged to the sanitary sewer.

u Some glucose tests contain zinc. Other typesare available and should be utilized wheneverpossible.

Pathology/HistologyProblem substances include mercury,glutaraldehyde, formaldehyde, alcohols,xylene, and other solvents.The most common hazardous materials found inpathology and histology labs are preservatives andfixatives used to prepare specimens.

u Waste glutaraldehyde, formaldehyde, alcohols,xylene, and other solvents should be collectedand disposed of as hazardous waste.

u Activated glutaraldehyde solutions lose theirtoxicity when held for a period of time (usually14 to 21 days). After that time they may beacceptable for discharge to the Regional WaterQuality Control Plant, as long as all other lawsand regulations are satisfied.

u Two common tissue fixatives, Zanker’s solutionand B5, are especially problematic because theycontain high levels of mercury. These solutionsare extremely hazardous and should be usedonly in the smallest possible volumes, with allwastes rinsed to hazardous waste contain-ment-never to a sink. While Zanker’s may bethe solution of choice in a few instances, labmanagers should discourage its use wheneverpossible. Expending the additional time andcare necessary to obtain excellent specimensusing other (non-metallic) fixatives will improvewater quality and reduce disposal costs.

MicrobiologyProblem substances include reagentscontaining heavy metals (such as copper andsilver) and solvents.u All staining supplies should be stored in

secondary containment.

u Both waste and contaminated rinsate volumescan be reduced if slides are stained with a fewdrops of solution rather than a dipping bath.

u If stains contain hazardous or metal ingredi-ents, rinse slides and containers to a hazardouswaste container.

ImmunodiagnosisProblem substances include copper sulfatesolutions and mercury.u Some slide preparation solutions contain

heavy metals and should be collected for off-site disposal. For example, copper sulfatesolutions should not be discarded or rinsedinto the sewer.

u Thimerisol, which contains mercury, is usedas a preservative in some buffer solutions.Alternatives to Thimerisol are available forsome applications. Sodium azide is one examplethat does not cause water pollution problems atlevels used for immunodiagnosis.

Gross Pathology andNecropsy

Problem substances include formaldehydesolutions, glutaraldehyde, alcohols, rinsesfrom silver staining, Zanker's solution, andzinc sulfate.u All formaldehyde solutions and specimens

stored in free solutions should be storedproperly in secondary containment, on securedshelving, and away from sinks. Refer to Labora-tories: Best Management Practices for WaterQuality Protection for storage guidelines.

u Waste solutions containing metals, includingrinses from silver staining and Zanker’s fixing(solution contains mercury and chromium),should be collected and managed as a hazard-ous waste.

u All waste solutions containing concentrationsof metals or formaldehyde above the dischargelimits for those substances must be collectedand disposed of as hazardous waste.

u Formaldehyde, glutaraldehyde, and alcohols,which are used in large quantities in pathologyand necropsy work, should be stored properlyand collected for proper disposal.

u Activated glutaraldehyde solutions lose theirtoxicity when held for a period of time (usually14 to 21 days). After that time they may be

acceptable for discharge to the Regional WaterQuality Control Plant, as long as all other lawsand regulations are satisfied.

u Use of Zanker’s solution and zinc sulfate forfixing can be eliminated in most cases. WhileZanker’s may be the solution of choice in a fewinstances, managers should discourage its usewhenever possible. Expending the additionaltime and care necessary to obtain excellentspecimens using other (non-metallic) fixativeswill improve water quality and reduce disposalcosts.

Equipment ContainingMercury

Because mercury is acutely toxic in extremely smallamounts, and because it is one of the metals thatconventional wastewater treatment plants cannotcompletely remove from sewage, mercury’s presencein medical facility wastewater is a serious problem forthe health of the Bay. Mercury is unlikely to beeliminatedfrom wastewater while medical facilitiescontinue to use equipment containing mercury.

u Whenever possible, replace mercury-containingequipment with equipment that does notcontain mercury.

u Use some of the many available alternatives tomercury thermometers, including alcohol (red)and digital thermometers for equipment suchas lab ovens and water baths.

u Make sure mercury spill cleanup kits areavailable in all areas where mercurycontainingequipment is used.

u Make sure the individual designated by thehospital’s environmental health and safetydepartment cleans up all mercury spills. If yourfacility does not have such a person, instruct allemployees in the proper handling and disposal(usually recycling) of mercury.

Notes

Facilities

Medical facilities present some special concernsfor pollution prevention:

u Plumbing

u Laundry

u Recirculating Hot Water Systems

u Water Purification Systems

u Vacuum Pumps

u Dehumidifiers and Air Conditioners

u Water Softening

u Limestone Sumps

u Cleaning and Maintenance Products

In many respects, facilities operationsand maintenance activities are the same forhospitals and medical centers as for any largebusiness or industry. In addition to the guide-lines in this booklet, please refer to the RegionalWater Quality Control Plant’s (RWQCP’s)best management practices for:

u Cooling towers

u Machine shops

u Vehicle service facilities

PlumbingMercury from inappropriate spill cleanup prac-tices and broken equipment often finds its wayto sewer lines and sumps, where it settles at lowpoints such as sumps and traps. The slow disso-lution of the mercury in a sump, trap, or pipecan release enough metal to cause dischargeviolations for mercury years after poor disposalpractices have been corrected.

u Whenever sewer lines, traps, or sumps aremoved or cleaned, caution should be takento avoid spilling the contents in case mer-cury is present. Non-water contents mustbe handled as hazardous waste unlessproven otherwise.

LaundryWhile the operation of hospital laundry facilitiesis tightly regulated for health concerns by theJoint Commission of Accredited HealthcareOrganizations (JCAHO), discharge to the seweris currently regulated only by local agenciessuch as the Regional Water Quality ControlPlant. The federal Environmental ProtectionAgency (EPA) plans to issue proposed rules,including pretreatment standards, for hospitalsand other industrial laundry facilities in Decem-ber 1996, and final rules in December 1998.

u Make sure no hazardous materials enterthe laundry (e.g. thermometers, rags usedto clean up hazardous materials spills).

u Reduce water use by recycling gray waterand using water-efficient equipment suchas tunnel washers and other automatedsystems.

u Wastewater discharged from laundryfacilities may contain significant amountsof metals as well as organics. The majorityof these pollutants come from launderedmaterials rather than laundry chemicals.While the RWQCP does not currentlyrequire treatment of hospital laundrywastewater before it is discharged to the

sewer, several “pretreatment” options (usedby laundries in other settings) are avail-able, including:

If studies indicate that treatment is prac-tical, local requirements may be set beforethe Federal standards are enacted in 1998.

u Store laundry chemicals properly insecondary containment, with incompatiblesubstances separated from each other.

Water Purification SystemsThe municipal water supply may contain dis-solved solids that are unacceptable for somemedical uses. These salts are commonlyremoved in treatment systems using ionexchange resins and/or reverse osmosis(RO). Deionized (DI) water is used to makeup laboratory reagents and to prepare dialysissolutions.

u Chemicals used for cleaning and disinfec-tion of DI and RO systems should be storedproperly in secondary containment, withacids and bases separated, on securedshelving and away from sinks.

u Disinfection of RO and DI should beaccomplished without the use of formalde-hyde. Sodium hypochlorite, bromine, andper-acetic acid disinfectants are appropriatesubstitutes. RO systems may be madecompatible with peracetic acid disinfectantssuch as Renalin and Actril. To do so, theRO membrane may need to be pretreatedto remove any iron, which reacts with theoxidizing solution and may form holes inthe membrane. (Some rubber or metalsystem components may also need to bereplaced.)

Recirculating Hot WaterSystems

Hospitals and other large medical facilitiesnormally employ some method of disinfection(in addition to that provided in the local drinkingwater supply) in order to combat infectiousagents, such as Legionella, within the system.Additional chlorination and water temperaturemaintained within the system above “household”levels (either constantly or intermittently) aretwo common strategies. Unfortunately, both ofthese methods may lead to increased corrosionof copper and lead in plumbing. This may be thehospital waste stream’s largest source of copper.

u Disinfection systems that use electrolysisto introduce copper and silver ions into thewater should be avoided because of theadded metals loading to wastewater. TheRWQCP has banned their use.

u Additional corrosion prevention measuresmay be necessary, such as reduced orintermittent chlorination, lowered orintermittent high temperatures, protectivemagnesium anodes, alternate pipingmaterials, slower recirculating rates, pHadjustment, and chemical controls such asaddition of sodium bicarbonate.

Vacuum Pumpsu Vacuum pump oil must be disposed of as a

hazardous waste.

u Water seal pumps should not be used sincethey can entrain solvents in the seal waste-water. Mechanical pumps without waterseals are preferable for water pollutionprevention. These pumps do not requirea connection to the sanitary sewer.

u Use of water aspirators has been banned bythe RWQCP They should be replaced withnon-water systems. Water aspirators canintroduce chemicals into wastewater andneedlessly waste large amounts of water.

u Cold traps on vacuum lines can be used tocapture volatile chemicals; however,. theyare rarely adequate for keeping all solventsout of pump seal water and pump oil.

u Do not use single-pass cooling water forvacuum pumps. Some single-pass coolingsystems waste as much as ten gallons ofwater per minute. Single-pass pumpsshould be replaced or retrofitted to recircu-lating cooling water systems. Savings inwater and sewer use fees can quickly payfor such modifications.

Dehumidifiers and AirConditioners

Condensate from dehumidifiers and air condi-tioners may be contaminated with small amountsof dirt, corroded metals, and oil.

u All such condensate flows should bereused when possible (in cooling towers,for example).

u If necessary, condensate drain lines shouldbe replumbed to facilitate recycling of thecondensate or discharge of the condensateto the sanitary sewer.

u New drainage lines must be plumbed tothe sanitary sewer, never to the storm drainsystem.

Water SofteningCommon water softeners exchange sodium forcalcium and magnesium in the water supply, andadd considerable salt loading (dissolved solids)to wastewater. A growing number of sewagetreatment plants have banned water softeners forthis reason. High dissolved solids content in theRWQCP’s effluent may limit uses of reclaimedwastewater.

u Medical facilities should soften water onlywhere absolutely necessary, such as forhemodialysis.

Limestone SumpsAcidic wastewater from laboratory areas mayneed to be neutralized before discharge to thesanitary sewer. Limestone neutralization sumpsare common in older construction. Water passesthrough a basin filled with limestone chips,where any acids are neutralized by the limestone.

u The pH of waste water from laboratoryareas can be controlled in the lab with acombination of proper training and collec-tion or neutralization of acids and bases.Therefore a limestone sump is oftenunnecessary.

u Limestone sumps are valuable samplingpoints for determining the effectivenessof a laboratory’s pollution control efforts.Unfortunately, they can also be collectionpoints for sediments (including elementalmercury). Limestone and sediments mustultimately be discarded as hazardouswaste.

u If a neutralization system is necessary,an appropriate equilibration tank orneutralization basin should be installed.

Cleaning and MaintenanceProducts

Cleaning and maintenance products maycontain pollutants such as metals, solvents,and tri-butyl tin.

u If possible, eliminate use of the followingproblem products:

Floor waxes or wax strippers thatcontain zinc

Toilet cleaning and disinfection productscontaining tri-butyl tin

Carpet and uphostery cleaners thatcontain ti-butyl tin

u Do not use cooling water systemadditives that contain copper, chromium,or tri-butyl tin.

u Paint and paint strippers contain solventsand metals that should not be disposed ofinto the sewer or storm drain system. Paintextra paint out of brushes. Brushes usedfor water-based paint can be rinsed in asink. Solvents and thinners used with oil-based paints should be filtered and reused.Extra paints, solvents, and paint residuethat cannot be reused or recycled must bemanaged as hazardous waste. Chemicalpaint-stripping waste is always hazardous.

u Use of copper-based root control productsis banned in the RWQCP service area.Mechanical root removal is the appropriatealternative.

u Maintain pools, spas, and fountains withoutuse of copper-based algaecides.

Laboratories

Best Management Practicesfor Water Quality Protection

Regional Water QualityControl Plant

Operated by the City of Palo Altofor the communities of East PaloAlto, Los Altos, Los Altos Hills,Palo Alto, and Stanford

BestManagement

Practicesfor

Laboratories

Contents

As part of a comprehensive program toreduce amounts of metals and chemi-cal contaminants reaching the watersof South San Francisco Bay, the Re-gional Water Quality Control Plant hasprepared this handbook of Best Man-agement Practices (BMPs) for labora-tories. Careful management of chemi-cals and waste liquids will have ameasurable. impact on the quality ofyour waste streams. Chemicals ofprimary concern to the RWQCP arelisted at the back of this brochure.

Drain protection ............... .3

Safety showers.. ................ .4

Container security.. ........... .5

Secondary containment ..... .6

Waste minimization.. ......... .7

Training ............................ 7

Wastewater disposal.. ........ .8

The sanitary sewer flows to the Re-gional Water Quality Control Plant,which has limited capacity to removechemical contaminants from sewage.Since the storm drain system flowsdirectly to creeks and the Bay with notreatment, it is also important to pro-tect storm drains from chemicals andother pollutants. In a sense, all of theBMPs in this booklet are intended toprovide “drain protection” - which iswater quality protection.

Never hold or store chemicals insinks.

Install lips around all sinks, espe-cially cup sinks on countertops andunder hoods.

Block floor drains in areas wherechemicals are used or stored.

Maintain sufficient and readilyavailable stocks of materials re-quired for spill cleanup(absorbents, drain plugs, acidbase neutralization kits, etc.).

Experiments andequipment . . . . . . . . . . . . . . . . . . . . . . 9

Guidelines for renovationand new construction... ... . 10

Water conservation . . . . . . . . . . 11For more information . . . . . . . 11

DrainProtection

Safetyshowers

Use one of three methods to keepspilled chemicals from reachingsafety shower drains:

Install a temporary plug thatopens automatically when thesafety shower is turned on.

Eliminate the drain.

Protect the safety shower drainfrom lab spills with a sump. Thecapacity of the sump must begreater than the volume of thelargest chemical container usedor stored in the lab, or the sumpmust be double-contained. Thesump may be covered by a grateto reduce hazards to people inthe area.

When an earthquake or accidentoccurs, the following practices shouldhelp prevent breakage or spills leadingto discharge of chemicals to the sewer.

Reduce spills by storing glasswareand other containers on texturedrubber mats.

Reduce bottle breakage by orderingchemicals in plastic coated bottleswhenever possible.

Always use plastic or insulatedholders for solvent bottles.

Never store chemicals above sinkson shelves or in cabinets. Store inapproved chemical cabinets or onlow shelves.

Always latch doors on chemicalstorage cabinets.

Secure chemicals stored on shelvesor in cabinets behind barriers ifsecondary containment is notfeasible. Barriers should be at leastl/5 the height of the tallest con-tainer.

Segregate incompatible chemicalsto prevent mixing in case of anaccidental spill. Use separate stor-age cabinets and closets or physicalbarriers such as independentsecondary containment, berming,or trenching.

Containersecurity

Secondarycontainment

Secondary containment for all regulatedchemicals should prevent leaks or spillsfrom reaching the sewer or storm drainsystem. The secondary containmentvessel or area (e.g. a tray, cannister, orbermed area) should be impervious tothe liquid being contained and largeenough to hold at least 110 percent ofthe capacity of the primary container.Secondary containment must not drainto any sewer.

Keep countertop chemical contain-ers, such as squirt bottles and smallflasks, in trays of appropriate capac-ity, or within bermed areas awayfrom sinks and drains.

Use secondary containment for allliquid chemicals stored on shelves orcountertops, or in cabinets.

Keep secondary containment dry atall times.

Again, never use a sink as secondarycontainment.

Reducing use of chemicals reduceschemical waste. Basic waste minimi-zation techniques include productsubstitution, reduced product usageand storage, recycling/reuse ofchemicals, modified operations, andwater conservation.

Substitute chemicals with lesstoxic alternatives.

Use the minimum amounts ofchemicals required by eachexperiment or process - tominimize disposal volume atend of procedure.

Order minimum amounts ofchemicals to reduce waste and left-over materials in case proceduresare changed, expiration dates pass,or spills occur.

All lab workers and employees shouldunderstand the importance of utilizingBest Management Practices for waterquality protection. Training for newemployees and refresher training forall staff are critically important.

Keep your lab’s Spill Response Planupdated and available to employeesat all times.

Train all lab workers in properchemical handling, storage, dis-posal, and water conservationpractices.

Waste minimization

Training

Wastewaterdisposal

To protect water quality in the Bay, allwastewater discharged to the sanitarysewer must be in compliance withlocal, state and federal regulations.

Discharge of substances may beprohibited due to pH, temperature,explosivity, radioactivity, etc., asspecified in your city’s sewer useordinance. See your company’shealth and safety officer for guide-lines on discharging reagents andchemicals that may be acceptableto your wastewater treatmentauthority.

Hazardous wastes, as defined bythe California Code of Regulations,Title 22, shall not be disposed ofvia the sanitary sewer.

Rinsate from chemical bottles andcontainers that have been in contactwith a hazardous material is ahazardous waste. During triple-rinsing, collect all such rinsate inappropriate waste containers withno discharge to the sewer, anddispose of it as a hazardous waste.

Many types of equipment used rou-tinely in the process of conductingexperiments may generate wasteswhich should not be discharged tothe sanitary sewer.

Do not use aspirators connected toa sink if you are vacuum-distillingor filtering chemicals that shouldnot go down the drain. (Suchaspirators also waste water.)

Use a rotary evaporator with acontained vacuum system and a dryice condenser to intercept solvents.

Make sure all chemical containersare properly labeled. Keep Materi-als Safety Data Sheets (MSDS) onfile for all chemicals.

Experimentsandequipment

Guidelinesfor

renovationand new

construction

Do not build chemical storageshelves or cabinets over sinks.

Install house vacuum systems thathave dry-seal or non-contact waterpumps. Pumps that use contactwater may discharge solvents to thesanitary sewer, causing the facilityto be in violation of dischargelimits.

If a safety shower will drain to alaboratory floor drain, construct thedrain in an appropriately sizedsump with a standpipe to ensurethat spilled chemicals do not godown the drain, but water from theshower itself can. Check with thelocal building code to determinewhether such sumps must bedouble-contained.

When plumbing new construction,segregate laboratory waste fromsanitary waste with separate piping.Provide a sampling port on thelaboratory waste line.

Consider installing holding tank(s),with sampling ports, to allow forcapture, testing, and release oflaboratory rinse water and/oraccidental spills. Multiple tankswith separate drains may be neces-sary to segregate incompatiblechemicals.

Select sinks with lips.

And don’t forget water conservation!Structural measures such as thoselisted below can make a reduce wateruse significantly. Well-trained labworkers use their ingenuity to savewater on the job.

Install water-saving devices (suchas flow restrictors) on sinks andrinse tanks.

Reduce rinse times if possible(without affecting product quality).

Recycle water - for example, to airscrubbers and cooling towers.

Eliminate one-pass water coolingsystems.

For additional copies of this brochureor the laboratory BMPs poster, or forinformation about the Regional WaterQuality Control Plant’s source reduc-tion programs, contact:

Regional Water Qual i ty

C o n t r o l P l a n t2 5 0 1 E m b a r c a d e r o W a yPalo Al to , CA 94303( 4 1 5 ) 3 2 9 - 2 5 9 8

We welcome your suggestions for thenext edition of this manual.

WaterConservation

For moreinformation

10

Chemicals of ConcernChlorinated alkanesmethyl chloridemethylene chloridemethyl bromidechloroformbromoformcarbon tetrachloridedichlorobromomethanechlorodibromomethanechloroethane1,1-dichloroethane1,2-dichloroethane1,1,1-trichloroethane1,1,2-trichloroethane1,1,2,2-tetrachloroethanehexachloroethane1,1-dichloroethylene1,2 trans-dichloroethylene1,2-dichloropropane1,2-dichloropropylenetr ichloroethylene tetrachloroethylenevinyl chloridehexachlorobutadienehexachlorocyclopentadiene

Chlorinated aromatics1,2,4-trichlorobenzenechlorobenzenehexachlorobenzene2-chloronaphthalene1,2-dichlorobenzene1,3-dichlorobenzene1,4-dichlorobenzene

Chlorinated ethersbis(chloromethyl) ether2-chloroethyl vinyl ether4-bromophenyl phenyl etherbis(2-chloroethoxy) methanebis(2-chloroethyl) ether4-chlorophenyl phenyl etherbis(c-chloroisopropyl) ether

Aromaticsbenzenetolueneethylbenzenenaphthalenefluorantheneacenaphthenebenzo(a) anthracene

benzo(a) pyrenechryseneindeno(1,2.3-c.d)pyrene3,4-benzofluoranthenebenzo(k)fluorantheneacenaphthyleneanthracenebenzo(ghl)perylenefluorenephenanthenedibenzo(a,h)anthracenepyrene

Phthalate estersbis(2-ethylexyl)phthalatebutyl benzyl phthalatedi-n-butyl phthalatedi-n-otyl phthalatediethyl phthalatedimethyl phthalate

Phenolsphenol2-chlorophenol2,4-dichlorophenolpentachlorophenol2-nitrophenol2,4-dimethylphenol4-nitrophenol2,4-dinitrophenol4,6-dinitro-o-cresol2,4,6-trichlorophenolpara-chloro-meta-cresol

Substituted aromatics1,2-diphenyl hydrazinenitrobenzene2,4-dinitrotoluene2,6-dinitrotoluene2,3,7,8-tetrachlorodibenzo-

p-dioxinbenzidine3,3-dichlorobenzidene

Polychlorinatedbi-phenylsPCB-1232PCB-1242PCB-1260PCB-1248PCB-1016PCB-1221

PCB-1254

Pesticidestoxaphenealdrindieldrinchlordane4,4-DDT4,4-DDE4,4-DDDa-endosulfan-alphab-endosulfan-betaendosulfan sulfateendrinendrin aldehydehepthachlorheptachlor epoxide3-bhc-alphab-bhc-betar-bhc(lindane)-gammag-bhc-delta

Metalsantimonyarsenicberylliumboroncadmiumchromium, hexavalentchromium, totalcobaltcopperleadmanganesemercurynickelseleniumsilverthalliumzinc

Miscellaneousacroleinacrylonitrileasbestoscyanideformaldehydeisophoronen-nitrosodiemethylaminen-nitrosodiphenylaminen-nitrosodi-n-propylamine

In the RWQCP service area, wastewater discharged to the sewer shall notcontain a sum total ofgreater than 1,000 mg/l of acetone, ethanol,methanol and isopropyl alcohol.