Pencinta Alam February 2013
Green Living Column
NANOTECHNOLOGY AND SAFETY: SOME QUESTIONS AND ANSWERS
Green Living Column
NANOTECHNOLOGY AND SAFETY: SOME QUESTIONS AND ANSWERS
You may be surprised to find out how many products on the market utilise nanotechnology.
* Sunscreen - Many sunscreens contain nanoparticles of zinc oxide or titanium oxide. Older sunscreen formulas use larger particles, which is what gives most sunscreens their whitish color. Smaller particles are less visible, meaning that when you rub the sunscreen into your skin, it doesn't give you a whitish tinge.
* Self-cleaning glass - A company called Pilkington offers a product they call Activ Glass, which uses nanoparticles to make the glassphotocatalytic and hydrophilic. The photocatalytic effect means that when UV radiation from light hits the glass, nanoparticles become energized and begin to break down and loosen organic molecules on the glass (in other words, dirt). Hydrophilic means that when water makes contact with the glass, it spreads across the glass evenly, which helps wash the glass clean.
* Clothing - Scientists are using nanoparticles to enhance your clothing. By coating fabrics with a thin layer of zinc oxide nanoparticles, manufacturers can create clothes that give better protection from UV radiation. Some clothes have nanoparticles in the form of little hairs or whiskers that help repel water and other materials, making the clothing stain-resistant.
* Scratch-resistant coatings - Engineers discovered that adding aluminum silicate nanoparticles to scratch-resistant polymer coatings made the coatings more effective, increasing resistance to chipping and scratching. Scratch-resistant coatings are common on everything from cars to eyeglass lenses.
* Antimicrobial bandages - Scientist Robert Burrell created a process to manufacture antibacterial bandages using nanoparticles of silver. Silver ions block microbes' cellular respiration [source:Burnsurgery.org]. In other words, silver smothers harmful cells, killing them.
Q: I’ve just heard that an organic certification agency has added nanotechnology to its list of forbidden things. What is it and should I be concerned about it?
A: Nanotechnology is a powerful platform for manipulating matter at the level of atoms and molecules in order to alter their properties. Nanomaterials are defined as particles having one or more dimensions of 100nm or less. One nanometer (nm) is one millionth of a millimeter and one billionth of a meter – or approximately one 80,000th of the width of a human hair. A strand of DNA is 2.5nm wide and a red blood cell 7,000 nm.
The fundamental properties of matter change at the nanoscale. According to research conducted at the University of Rochester’s Department of Environmental Medicine and published in Environmental Health Perspectives in 2005, altered properties can include color, solubility, material strength, electrical conductivity, magnetic behavior, mobility (within the environment and within the human body), chemical reactivity and biological activity.
The manufacture of products using nanotechnology has exploded in recent years, creating something akin to a gold rush mentality. More than 720 products containing nanomaterials are now on the market. They include sunscreens and cosmetics, food additives, temperature-moderating clothing, food packaging, agricultural fertilizers, computer chips and mobile phones, inks, computer storage devices and displays, football stadium lights, tennis racquets, burn dressings and dental binding agents. Nanotechnology proponents envision it being used in the future to create cheaper ways of producing electricity from the sun, earlier and better diagnostics and treatment of diseases and water purification in developing countries. Currently, there is an estimated $9 billion a year worth of research being done.
There is no doubt that nanotechnology will have a massive impact on all industries and sectors of the economy, society and ecology. Opinion is divided as to whether these changes will be positive or negative. But there is enough concern that The Soil Association in the U.K. – one of the world’s pioneers of organic agriculture – announced in January that it has banned human-made nano- materials from the organic cosmetics, foods and textiles that it certifies. A 2007 survey by 15 governments estimates there are at least 70 nanotech food-related applications already on the market and most major food and beverage corporations are investing in nanotech R&D.
In a statement, The Soil Association explained its motivation: “Our concern with nanoparticles lies in the fact that the properties of materials at this size can differ significantly from those at larger scales. Nanoparticles are so small they can sometimes bypass the body’s natural protective boundaries such as skin…Industry and government are belatedly conducting safety tests that will take several years to reach firm conclusions. Therefore we’ve applied the precautionary principle.”
And that’s the problem: Products containing nanomaterials have been released commercially in the absence of regulatory oversight and in spite of warnings from some of the oldest and most respected scientific bodies in the world, such as the U.K.’s Royal Society and the Royal Academy of Engineering, which published a report in 2004 urging tighter controls on the industry, suggesting that nanomaterials be treated like new chemicals.
In particular, the report highlighted the potential risk of “free” nanoparticles that it said could escape into the atmosphere, be inhaled and have an effect on health, in the same way that ultra fine particles that are a by-produce of forest fires, volcanoes and processes like welding and vehicle combustion can be harmful to health. Professor Mark Welland, head of the University of Cambridge Nanoscale Science Laboratory, says that we know inhaled nanoparticles found in the bloodstream have dispersed throughout the brain. But, he adds, it is not known if this poses a health risk.
According to a 2006 report prepared under the auspices of the U.S. Congress by that country’s National Research Council, there is also evidence that engineered nanoparticles can have adverse effects on the health of laboratory animals, enter human cells and trigger chemical reactions in soil, interfering with biological and ecological processes. That report also urged precaution to protect the health and safety of workers, the public and the environment.
Oxford University’s Dr. Alexis Vlandas is Nanotechnology spokesperson for International Network of Engineers and Scientists for Global Responsibility also worries about nanoparticles entering the human body. He says, “A much more proactive effort is needed to understand the complex phenomena (bio-accumulation, degradation, unforeseen chemical reactions, etc.) which could lead to negative impact on human health or the environment.”
Nevertheless, there is still no legal requirement anywhere in the world for manufacturers to conduct new safety tests on nano-scale ingredients. Nor is there any requirement for manufacturers to demonstrate that they do not present a negative impact to the environment or to indicate the presence of nano-scale ingredients on product labels. In fact, there is not even an internationally accepted nomenclature, set of definitions and measurement systems for nanotechnology, although that is being worked on. And, finally, the social, economic and ethical challenges posed by nanotechnologies have yet to be addressed.
Nowhere are untested nanomaterials entering consumer products faster than in the personal care and cosmetics industries. And their use is of concern because these products are used daily and are designed to be used directly on the skin. They may be inhaled and are often ingested. While the jury is still out on whether nanomaterials can enter intact skin, studies show that broken skin is an ineffective barrier. This suggests that the presence of acne, eczema or shaving wounds is likely to enable the uptake of nanoparticles into the body. Furthermore, in preparing its 2006 report Nanomaterials, Sunscreen and Cosmetics: Small Ingredients, Big Risks, Friends of the Earth (FOE) found that many cosmetics and personal care products contain ingredients that intentionally act as “penetration enhancers,” raising concerns they may increase the likelihood of skin uptake of nanomaterials and possible entry into the blood stream.
Nano-scale carbon molecules called “fullerenes” or “buckyballs” are among the ingredients currently being used in face creams and moisturizers. They have been found to cause brain damage in fish. Even low levels of exposure to fullerenes have been shown to damage human liver cells. Chemistry professor Tony Ryan of the University of Sheffield in England has questioned their safety. “I wouldn’t put buckyballs anywhere near my face,” he says. “We need to understand more about the toxicology. One of the potential dangers…is: Are we creating a new asbestos? The asbestosis response is based on the shape of the particle. Part of the issue is in the shape of the molecule and how they’re introduced. We just need to be careful about the risk versus the benefit.”
Nanoparticles of zinc oxide and titanium dioxide are used to make sunscreens transparent but, says FOE, they have been shown to be photoactive, producing free radicals and causing DNA damage to skin cells when exposed to UV light. In 2007, Consumer Reports asked an outside lab to test for nanoparticles of zinc oxide and titanium dioxide in eight sunscreens that listed either compound on their label. All eight contained the nanoparticles, yet only one disclosed their use.
The ETC Group, a pioneering Ottawa-based organization working on global issues like biotechnology, conservation of agricultural biodiversity and food security, takes a strong stand on nanotechnology. It cautions that while it offers opportunities for society, it also involves profound ethical, social and environmental risks, not only because it is an enabling technology to the biotech industry, but also because it involves atomic manipulation and will make possible the fusing of the biological world and the mechanical. In 2003, the ETC Group called for a moratorium on research involving molecular self-assembly and self-replication until the ramifications have been studied.
They’re not the only organization calling for a moratorium. FOE-US has called for a moratorium on all commercial release of nanotechnological materials and products. They say, “Given the serious risks and impacts associated with nanotechnology’s introduction, public involvement in decision making regarding nanotechnology and the introduction of a regulatory regime based on the precautionary principle must be prerequisites to further commercialization of nanoproducts.”
In July of 2007, an international coalition of consumer, public health, environmental, labor, and civil society organizations spanning six continents called for strong, comprehensive over sight of nanotechnology and its products. Over 40 groups released a paper entitled Principles for the Oversight of Nano-technologies and Nanomaterials, citing risks to the public, workers and the environment and demanding a moratorium on it pending research and regulation.
“Even though potential health hazards stemming from exposure have been clearly identified, there are no mandatory workplace measures that require exposures to be assessed, workers to be trained or control measures to be implemented,” explains Bill Kojola of the AFL-CIO, which was part of the coalition. “This technology should not be rushed to market until these failings are corrected and workers assured of their safety.”
“Nanomaterials are entering the environment during manufacture, use and disposal of hundreds of products, even though we have no way to track the effects of this potent new form of pollution,” agrees Ian Illuminato of FOE. “By the time monitoring catches up to commerce, the damage will already have been done.”
There is also a concern that nano-technology will provide the tools for continuous surveillance, with implications for civil liberties. And then there’s the growing nano arms race, which could create a whole new generation of weapons of mass destruction including nano-biological weaponry. Over a decade ago, retired U.S. Admiral David Jeremiah told a conference on nanotechnology and global security that nanotechnology will prove more significant than nuclear weapons.
Fortunately, public pressure seems to be goading governments into action. The Environment, Healthy and Safety Division of the Organization for Economic Co-operation and Development has made the safety of nanomaterials a priority. Canada, Germany, Japan, Australia the U.K. and the U.S. have created working groups to look into the implications of nanotechnology commercialization.
However, the amounts of money being spent are minuscule in comparison to the $6 billion spent last year by governments worldwide on nanotech. (The U.S. government’s $5 billion between 2001 and 2006 is the biggest publicly funded science endeavor since the Apollo moon landing, with the largest portion funding military applications.)
In Canada, the Consumers Council has recently received a $60,000 grant from Canada’s Office of Consumer Affairs to study the impact of nanotechnology on consumers and to improve the capacity of consumers to advocate regarding regulatory decisions.
Here’s hoping other organic certification agencies follow The Soil Association’s lead and add nanotech to their lists of outlawed ingredients. Meanwhile, we think that product manufacturers and distributors must bear the burden of proof to demonstrate the safety of their products: If there is no independent health and safety data review for a nanotech product, then their products shouldn’t be sold.
(Edited and compiled from an original article by Wendy Priesnitz. Available at: http://www.naturallifemagazine.com/0804/asknl.htm)
Not enough data exists to know for sure if nanoparticles could have undesirable effects on the environment. Two areas are relevant here:
(1) In free form nanoparticles can be released in the air or water during production (or production accidents) or as waste by-product of production, and ultimately accumulate in the soil, water or plant life.
(2) In fixed form, where they are part of a manufactured substance or product, they will ultimately have to be recycled or disposed of as waste. It is not known yet whether certain nanoparticles will constitute a completely new class of non-biodegradable pollutant. In case they do, it is not known how such pollutants could be removed from air or water because most traditional filters are not suitable for such tasks (their pores are too big to catch nanoparticles).
Of the US$710 million spent in 2002 by the U.S. government on nanotechnology research, only $500,000 was spent on environmental impact assessments. Risks identified include: self-replicating nanobots aggressively or through slowly rising supremacy wiping out the whole biosphere; further destabilising the already endangered diversity of the biosphere.
Concerns have been raised about Silver Nano technology used by Samsung in a range of appliances such as washing machines and air purifiers.
To properly assess the health hazards of engineered nanoparticles the whole life cycle of these particles needs to be evaluated, including their fabrication, storage and distribution, application and potential abuse, and disposal. The impact on humans or the environment may vary at different stages of the life cycle.
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