nanotechnology is it in need for a paradigm shift

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Tarun Batra et al., IJSID 2011, 1 (3), 34-45

International Journal of Science Innovations and Discoveries, Volume 1, Issue 3, November-December 2011

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NANOTECHNOLOGY: IS IT IN NEED FOR A PARADIGM SHIFT?

Dr. Tarun Batra

Voice for Earth International, 225,Cedar Hill St.,Suite 200 Marlborough, MA 01752 USA

INTRODUCTION

INTRODUCTION

ISSN:2249-5347 IJSID

International Journal of Science Innovations and Discoveries An International peer

Review Journal for Science

Review Article Available online through www.ijsidonline.info

Received: 16.09.2011

Modified: 13.10.2011

Published: 29.12.2011

*Corresponding Author

Name:

Dr. Tarun BatraPlace:

Marlborough , USA

E-mail: [email protected]

ABSTRACT

Nanomaterials are invisible to the normal human eye and are visible

through microscopes. These are increasingly used for commercial purposes

such as fillers, opacifiers, catalysts, semiconductors, cosmetics, micro

electronics and drug carriers. Materials in this size range approach the length

scale at which some specific physical or chemical interactions with their

environment can occur. Nanotechnology creates improved materials, devices

and systems that exploit these new and unique properties to come up with a

totally different bulk material with different properties As a result, their

properties differ substantially from those bulk materials of the same

composition, allowing them to perform exceptional feats of conductivity,

reactivity and optical sensitivity. Possible undesirable results of these

capabilities are harmful interactions with biological systems and the

environment, with the potential to generate toxicity. Risks associated with

current nanosized materials are currently undefined and appear manageable.

However, predicted evolution and refinement of nanotechnology in the near

future will require the establishment of safety principles and test procedures

to ensure safe research, manufacture, use and disposal of nanomaterials.

Evaluating these current and future risks of nanotechnology is necessary and

achievable.

Keywords Nanotechnology, Risks, Nanomaterials, Safe Material, Health

Concerns, Safety, Occupational Health, Environmental Health





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INTRODUCTION

Nanotechnology is the science that deals with manipulations of basic matter: atoms and molecules which

are as small as 1 to 100 nanometers. A nanometer is equal to one billionth of a meter or 10-9. For comparison, a

flea is 10-3 or 1 mm, a human hair is 10 -4 or 80 μm, a red blood cell is 10-5 or 7 μm, a strand of DNA is 10-8 or 2

nm, a bundle of carbon nanotubes is approximately 1.4 nm wide, a carbon 60 fullerene (sometimes called a

buckeyball) is 0.7 nm. A significant point to derive from this comparison is that a nanoparticle is considerably

smaller than a red blood cell and that red blood cells move freely throughout the circulatory system of the human

body from the arteries to the capillaries (Aftanski 2005).

Opportunities brought about by nanotechnology

There is wide agreement and expectation that nanotechnology will be the next industrial revolution and

the key to tomorrow that gives huge opportunities as well as massive applications. There is noteworthy

government investment and worldwide attention on nanotechnology. Although there are conflicts and differences

about the definition of what nanotechnology is; the widest definition is engineered structures, devices and systems

that have a length of 1-100 nanometers. This is the juncture that allows the substances to begin showing distinct

properties and influence their physical, chemical and biological behavior . This field is vital in most of the

technologies that depend on this process which take place at nanometer scale. These include carbon tubes,

titanium dioxide, silicon/germanium, calcium oxide based materials, metal-cored coated particles and proteins /

DNA.

Nanotechnology has several applications (Figure 1) and products that are sub-dividend into threecategories. These are:

1. Bottom up. In this category atoms or molecules are allowed to grow through self assembly into large structures.

2. Top down, whereby bulk materials are reduced in size to produce nanometer-scale particles which are

systematically inserted into larger structures or are used as admixture to other materials.

3. Self-assembly components spontaneously assemble frequently by moving in a solution or gas phase. Until a

stable structure of minimum energy is reached. The commonest known nanofactory to human kind is a living cell.

Nanotechnology is currently used in electronic, magnetic, optoelectronic, biomedical, pharmaceutical,

cosmetic, energy, catalytic and materials industries. The greatest revenues for nanoparticles include chemical &mechanical polishing, magnetic recording tapes, sunscreens, automotive catalyst supports, biolabelling, electro-

conductive coatings and optical fibers. They are also used in medical fields in helping in drug delivery and medical

imaging. It is also projected that nanotechnology will contribute to new cancer therapies. In Artificial intelligence ,

nanorobots and self assembly is also expected to increase in the near future.





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Figure 1

Challenges introduced by nanotechnology

Because of their very small size and large surface area, engineered nanomaterials present certain Safety,

Health and Environmental hazards, which are unknown with non-nanomaterials (Figure 2). The concern is that

nanomaterials are being used in products or are being considered for other uses without a clear perspective on the

Safety, Health and Environmental impact of such uses (Knowles 2006). At the nanoscale, the laws of physics,

biology and chemistry merge and the behavior of these small particles changes, such as their mobility in the

environment, reactivity, toxicity and ability to enter the human body (Hett 2004).Notwithstanding the bright





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future promised by nanotechnology, there are issues that accompany this technology that raise serious concern

about the health and safety aspect of the nanoparticles that has not been fully studied. However, this should not

deter any progress in this field as there are many human problems that can be solved using this technology such as

environmental issues. There are at least six hundred types of businesses that invest in nanotechnology in which

most are small and medium enterprises specially the ones being established currently. Multiple issues face this

industry as there are huge gaps in knowledge, resources that can enable these establishments to deal with the

nanotechnology environmental health and safety issues at the work places. (Lekas, Lifeset and Rejeski 2006).

Figure 2

Dealing with environmental health and safety issues accrued from nanotechnology is complex and not an

easy task (Hull 2007). Many organizations in nanotechnology have no clarity on the present regulations set by the

federal and state government on environmental health and safety. This comes as studies reveal that the toxic

substances control act, resource conservation and recovery act among others have a direct mandate on the

nanotechnology (Hull 2007).





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Nanoparticles can enter human body through several paths that include inhalation into the blood stream

through the lungs, digestive track,and the blood brain barrier(Capello 2005). There are more than two million

nanotechnology workers exposed to these particles every day and this number may more than double as more

people venture into businesses worldwide.

There are many effects of nanoparticles exposure and lack of comprehensive research in this field makes it

hard to accurately realize the extent of the effects. Some of the effects include inhalation, ingestion, dermal contact

and there is minimal data on the common exposure routes. In addressing health and environmental impacts

related to nanomaterials, there is a need to separate the two types of nanostructures that are:

a) Nanocomposites: Nanostructure surfaces and nanocomponents such as electronic, optical and sensors among

others. In this category, nanoscale particles are incorporated into a substance, material or device.

b) Free nanoparticles where in certain stages of production or use, nanoparticles of a substance are present. These

could be nanoscale species of elements or simple compounds, but also complex compounds which may be coated.

Nanotoxicology

Recent studies by the National Science Foundation and the US Environmental Protection Agency identified

several critical risk assessment issues touching on manufactured nanoparticles. These include exposure

assessment of manufactured nanoparticles, toxicology of manufactured nanoparticles, ability to extrapolate

manufactured nanoparticle toxicity using existing particle and fiber toxicology databases, environmental and

biological outcome, transport, persistence and transformation of manufactured nanoparticles as well as

recyclability and overall sustainability of manufactured nanomaterials (Dreher 2003).

A great concern of nanoparticles is their inability to always be detected after their release into the

environment, potentially creating difficulties in creation of remedy where need be. There are nanoparticles that

accrue from manufacturing industries such as carbon nanotubes, combustion derived nanoparticles such as diesel

soot and naturally occurring nanoparticles such as volcanic eruptions and atmospheric chemistry. Such may lead

to inflammatory diseases affecting lung tissues, liver, skin, gut, blood or brain.

a. Biodistribution:

It is not clear yet how the nanoparticles behave inside the body among many scientists. Their behavior is a

total sum of their size, shape and surface reactivity with the surrounding tissues. However, it is suggested that these particles may overload the body’s phagocytes triggering stress reactions and hence leading to immune-

suppression. There are issues raised on non-degradable nanoparticles accumulate into the organs of the body and

interference of various biological processes. Nanotechnology materials have the unique capability of penetrating

cell membranes into the cells, organs and tissues owing to their size (Holsapple et al 2005). Once into the body,

they are toxic to the body altering several functions such as increasing the rates of oxidation, inflammation and

eventually cell death (Oberdorster et al 2005). Further studies show that these particles may lead to DNA mutation





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and cause major destructions to the structures of the cell such as mitochondria and others; such issues are fatal as

they result to cell death (Porter et al 2007).

National Institute of Occupational Safety & Health (NIOSH) conducted a study in 2009 on workers exposed

to aerosols of some manufactured or coincidental microscopic and nanoscale particles which showed adverse lung

effects that comprised lung function decrement and obstructive and fibrotic lung diseases. Such impacts according

to NIOSH are uncertain in their implications. Recently, a study revealed that the large surface area of the

nanoparticles compared to their volume makes a person come into contact with huge number of the nanoparticles

compared to other larger particles (Empa 2011).

b. Nanopollution:

Nanogeneric devices and the process of nano-manufacturing releases wastes which may be very

catastrophic because of its size. It is able to be suspended into the air, can easily penetrate animal and plant cell

with unknown effects. Scientists observed that socks coated with nanosilver although marked as non odor forming

and saving many people the embarrassment of smelling feet had some effects on the environment. When these

socks were soaked in water, six types of them were found to leach silver particles into the distilled water. However,

there were varied levels of silver released into the water drawing attention over the method and quality of the

manufacturing process. This study raised concerns over the release of silver into the ecosystems through waste

waters.

A committee was formed in 2007 to discuss and gain better comprehension of the upcoming

nanotechnology sector. The committee constituted Massachusetts Department of Environmental Protection

(MassDEP), Department of Public Health (DPH), Division of Occupational Safety (DOS), Office of Technical

Assistance (OTA), and Office of Business Development (MOBD). Each of these agencies had distinct authority and

brought different versions of interests to the committee (Marriott, Marlborough and Massachusetts 2007). Such

multi-sectoral approaches are able to shed more light into the opportunities and challenges of nanotechnology.

Center for Disease Control (CDC) clearly stated that workers are at the first risk to nanotechnology health

and safety risks. These have a higher potential to be exposed to unique engineered materials with novel sizes,

shapes, and physical and chemical and biological behavior properties. It is surprising that occupational health risks

associated with manufacturing and using nanomaterials are not well comprehended with limited informationavailable.

NIOSH, the leading federal agency in conducting research on occupational health safety and health

implications and applications of nanotechnology, identified ten critical areas that can help in addressing the

existing knowledge gaps, develop strategies and provide recommendations. Such moves are more than welcome

owing to the unprecedented spread of nanotechnology worldwide.

These key areas include:





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1. Toxicity and determination of the physical and chemical properties such as size, shape an solubility that play a

role in influencing the toxicity of the nanoparticles; evaluation of short-term to long term posed by these

particles on the organs and cells.; determining biological mechanism for potential toxic effects; and this data

will help in creation and integration of models that will aid in assessing the potential hazards.

2. Risk assessment. This involves determining the likelihood that present exposure. Response data can be used to

identify and assess potential occupation hazards. This is followed by creation of a framework for evaluating

potential hazards and predicting potential occupation risks of exposure to nanomaterials.

3. Measurement methods. This included evaluating the methods of measuring mass of particles in the air that can

be inhaled and develop methods that can accurately measure the airborne nanomaterials in the work place and

also compare and validate the sampling instruments.

4. Exposure assessment that focused on determining factors that influence the production, spread and

accumulation and re-entry of nanomaterials into work places. Assessment of possible exposure once these

material are inhaled or stick on the skin.Differentiate various work places and magnitudes of exposure and

finally assess the impacts of these nanomaterials on the body.

5. The other key ingredient and focus was identifying the uses of nanotechnology for application in occupational

safety and health as well as evaluate and disseminate effective applications to workers and occupational safety

and health professionals.

Nonetheless, even with many committees being formed, the dangers posed by nanotechnology especially to

industry workers are real and require keen and urgent attention. Questions over the ability of these methods to

mitigate any harmful exposures will most often go unanswered owing to the unavailability of accurate and

sufficient data and information regarding the impacts of nanotechnology on human and environment. Much

debates and speculations currently fill the air among many scientists and scholars while at the same time

nanotechnology spreads like bush fire across the different continents of the world.

How protective is protective equipment in nanotechnology

With huge uncertainties that follow this field, serious issues arise as to the effectiveness of the protective

equipments. There are concerns over the lack of regulation touching on nanotechnology, exposing many workers

to uncertain dangers. It is interesting to note that there is only a voluntary guideline issued by the USEnvironmental Protection Agency (EPA) and Food and Drug Administration (FDA) to industries regarding

nanotechnology (Ronallo 2011).

There are many procedures needed to develop and implement a nano-specific regulatory structure. That

includes a proper definition of what nanotechnology /engineered nanomaterials are, identification of

nanoproducts in the market and those already in the manufacturing processes.

There is still a long way to go to ensure workplace safety and health for the workers in nanotechnology

industries. Many companies had monitoring services that evaluate the work place areas but significantly lack the





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mechanisms for dealing with potential contamination. Some of them used simple methods like sweeping and

vacuuming as protective measures. These methods are detrimental in that they disperse the nanoparticles into the

air putting many more people at risk instead of cleaning them up.

There is a wide recognition and call for clear regulations and protection of both workers and consumers of

nanoproducts world wide. Many companies are putting their workforce at greater risks by doing almost nothing to

ensure the protection of their staffs. Studies conducted by University of California on 78 international industries

that worked with nanoparticles found out that most of these companies were uncertain on the right way to handle

these nanoparticles, protect their workers, dispose the wastes among other vitally important things in terms of

environmental protection and conservation. Less than 50 % of the industries studied had no specific protective

program that directly handles nanoparticles. Most of them had vague guidelines and protection measures.

Although the governments are putting guidelines to encourage industries to regulate themselves, there are huge

knowledge and information gaps that limit the ability of the government agencies to exert proper control of the

safety of the workers in these industries from nanoparticles or even the consumers of the nanoproducts. Most of

the nanomaterial applications are classified as confidential business information while the ones reaching public’s

attention have little testing by regulatory authorities for human health, safety and environmental effects (Ronallo

2011). A study of forty companies carried out in Switzerland and Germany revealed that over 67% lacked

mechanisms and did not conduct any risk assessment on their nanomaterial and very few put focus on the issues

that may affect the end users of these products as well as the workers exposure (Helland et al 2008).

The United States Department of Labor concurs that workers who use nanomaterials in research or

production processes may be exposed to nanoparticles through inhalation, dermal contact, or ingestion. This

depends on how the employees handle and use the nanomaterial and if there are proper protective equipments to

shield them from the harmful exposure. Precisely, workers in these places face nanotoxicity depending on the

physical and chemical properties of the particle. Recently, a clinical study pointed out that long term exposure to

nanoparticles may lead to human toxicity. There are records of seven female Chinese workers who were diagnosed

with unusual and progressive lung damage and later two of these workers passed away owing to the lung damage

(Maynard 2009). All of them worked in a facility spraying a polycyclic ester paste onto polystyrene substrate that

was then heat cured. This work took place in an area with poor ventilation. Also, there is evidence that five monthbefore the lung disease was identified; the local exhaust ventilation had broken down and did not undergo any

kind of repair. The patents suffered from shortness of breath and excessive liquid in the cavity that surrounds the

lungs. Tests on the lung tissues showed non-specific inflammation, pulmonary fibrosis, and foreign body

granulomas of the pleura. Five of the patients were found to have pericardial effusions, which in simple terms

means -excessive liquid around the heart (Maynard 2009). Most of the studies are challenged by lack of sufficient

data on the nature or magnitude of exposure in work places and although many industries may take advantage of

this confusion, there is a fundamental responsibility to protect and sustain basic human rights such as right to life.





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Governments and government agencies through restrictive budgetary allocations have failed to keep in pace with

the high speed growth of nanotechnology and owing to the fact that industries will always act in self preservation

interests, more damage may be done before reality fully sets in. Institutional failure has seen regulatory demands

being left to individual industries to monitor the exposures and impacts of nanotechnology effects among other

things.

Conflicts over threats posed by nanotechnology

To some extent, it is believed that currently there are no threats posed by nanotechnology that warrant any

form of regulation or attention (Shalleck 2006). In addition, nanotechnology industry is under self- regulating

control with enough government regulations and supervision that enables it to progress safely and friendly to the

environment. However, it will be correct to say that private ventures are instituted with the motive of making

maximum profit under minimal costs (Shalleck 2006). There has never been an institution that sustainably

monitored itself in matters that require restrained exploitation of resources. It should also be noted that nobody

has ever washed a hired vehicle, past events have made it clear that without serious government involvement in

terms of research and financing the institutions in place, more people will be affected by the nanoparticles

especially in the work places.

There are calls by various stakeholders to rise up with independent and authoritative information on the

risks of nanotechnology and how these risks can be mitigated; otherwise speculations may lead to decline in the

development and advancement of nanotechnology. There are some tangible efforts beginning to emerge among the

scientists, government and research organizations on ways to minimize the risks posed by the nanotechnology

without jeopardizing their ability to continually offer valuable services to humanity and environment.

Even in the presence of the commitments and efforts that may support risk focused research, opportunities to

establish collaborative, integrated and targeted research programs are being missed(Maynard et al 2006).

Moreover, it is sure that whereas fears over nanotechnology work place risks may be way too high exaggerated,

but they are not unfounded(Maynard et al 2006).

Though there are wide agreements on the potential harmful effects of the nanomaterials to human and

environment especially workers in these industries, research into this field attracts little funding as well as less

priority from the intellectual property and technology development. Notwithstanding the challenges posed by thenanotechnology, there is a little focus on how the risks are handled and mitigated. Without much strategic and

targeted risk studies, people working in nanotechnology industries and the consumers of these goods could

develop unanticipated illness owing to exposure(Maynard et al 2006). While this may not be a huge issue now to

the law makers and industries, such effects may have future negative effects on the nanotechnology good where

their demand may go low due to losses in consumer confidence.

CONCLUSION AND RECOMMENDATIONS





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It is clear that nanotechnology is as young and hence not much is known about it. There is however, a great

challenge to see to it that companies and industries come up with strategies to implement rational risk control

measures that can protect the workers in this field. Nanotechnology has drawn many comparisons with asbestos

that caused diseases as nothing much of them were known, the similarity between asbestos and nanotechnology is

the fact that they both are in the range of nanosize.

It is significant to note that nanotechnology has made huge progress over the last two years and researches

have led to discoveries of more nanotechnology applications and produce revenue of over USD $1.1 Trillion worth

of products in 2007 (David and Judy 2008).

Legislative and institutional framework

However, there are currently no regulations at the federal government level in the United States over

nanotechnology handling although there are minor steps being taken by the local and state governments. The

existing regulations set by the government agencies on the other hand face several limitations as their enforcement

is limited. There is a definite need for the physicians and health and safety developments to keep up-to-date

records on the toxicology reports in the nanotechnology industry. There is a need to look beyond the industry and

company boundaries and follow these nanomaterials at the consumer levels as well as their release into the

environment.There is a whole lot of dollars devoted towards nanotech research in terms of widening their

applications and very little attention is given to safety and environmental concerns on this area of technology. This

calls for a paradigm shift on the interests of technology to more holistic approaches that will sustainably improve

the quality of life on planet earth.

There are many issues and threats that currently face the world wide ecosystem as well as local

ecosystems. It has been proven that nanoparticles degrade at much slower and can easily move from organs into

the blood stream and finally into the brain, thus creating an environmental as well as a toxicity issue.

Research Priority & Collaboration

Safety research in the field of nanotechnology is limited by lack of coordination and research prioritization,

which has resulted in very less awareness on nanotechnology and its potential negative impacts. There is a need

for genuine government and industry commitment to spend and disseminate knowledge regarding the real threats

posed by this future technology. There is a need for industries to ensure their workers are fully protected fromharmful exposure when handling nanomaterials. However, this can only be done when there are collaborated

efforts from all stakeholders to help take informed decisions and progress with safer workplace practices.

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nanotechnology is it in need for a paradigm shift

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