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"Earthworms are excellent indicators of soil health, and provide vitally important ecosystem services by aerating the soil, cycling nutrients, and increasing microbial activity. The Alterra study, led by Doctoral candidate Merel van der Ploeg, compared the health and growth of earthworms in soil containing carbon and silver nanoparticles at varying amounts with worms in regular soil. Mr. Van der Ploeg found the soil containing nanoparticles reduced reproduction, slowed growth, and increased the mortality rate of exposed earthworms. Young worms are particularly sensitive to the effects of the nanomaterial. Mr. Van der Ploeg notes, 'I also found damage to the skin tissue and intestinal wall, often accompanied by damage to the underlying muscle, but even though tissue damage is usually associated with inflammation, I did not observe this in the earthworms. There seemed to be a suppression of the immune system.'"
"Zinc oxide nanoparticles are more toxic to marine algae than bulk zinc oxide, according to an Italian study... The nanoparticles affected algal growth more than the bulk compound, say the researchers, most likely because of 'peculiar physicochemical properties of the nanostate'."
Europe is failing to control a burgeoning industry in microscopic materials, prompting claims that it has failed to heed the lessons from millions of asbestos deaths, according to a hard-hitting new report... A major study published by the European Environment Agency (EEA) last week says European governments – including the UK's – are "paralysed by analysis" and failing to act: "Twenty years have elapsed since first indications of nanomaterial harm were published", it said, "and in the intervening time an increasing body of literature has been developed on how nanomaterials interact with cells, mammals and aquatic organisms. Yet many governments still call for more information as a substitute for action."
"The U.S. Environmental Protection Agency (EPA) recently faced tough questioning from the U.S. Court of Appeals for the Ninth Circuit over its decision to conditionally approve a pesticide product containing nanosilver as the active ingredient. The antimicrobial pesticide product, HeiQ AGS-20, contains microscopic particles of silver and has been applied to textiles such as clothes, blankets, and pillowcases, in an attempt to suppress odor and bacterial growth... Because of their size, nanoparticles can be easily inhaled, absorbed by skin contact, or ingested. Little to no information is known about the fate or effects nanoparticles, specifically nanosilver, can have on the digestive tract, lung, or skin of those that are exposed to these particles. Research is still ongoing to investigate whether nanosize particles cause pulmonary inflammation as well as systemic effects, and whether they translocate from the lungs to other organs such as the liver, kidney or brain. Preliminary research with laboratory rats has found that nanosilver can traverse into the brain, and can induce neuronal degeneration and necrosis (death of cells or tissue) by accumulating in the brain over a long period of time. Low doses of nanosilver can also make bacteria stronger and more resistant."
Results: There was no overt sign of clinical toxicity in either MPS- or Col-treated mice. However, MPS NPs led to significant increases in liver and spleen weight and splenocyte proliferation. Mice treated with MPS NPs showed altered lymphocyte populations (CD3+, CD45+, CD4+, and CD8+) in the spleen, increased serum IgG and IgM levels, and histological changes. Despite slight changes in lymphocyte populations in the spleen, Col NPs did not alter other immunological factors.
Conclusion: The results indicate that in vivo exposure to MPS NPs caused more damage to systemic immunity than that of Col NPs through the dysregulation of the spleen. The results for in vivo data are inconsistent with those for in vitro data, which show lower cytotoxicity for MPS NPs. These results suggest the importance of verifying biocompatibility both in vitro and in vivo during the design of new nanomaterials.
The insurance company GenRe has published a report on potential liabilities and related insurance issues surrounding the use of nanotechnologies in products. The report recommends nanotechnology should be taken into account when insurers underwrite now, saying that it is "essential to initiate a process that systematically deals with these technologies and their potential risks from an insurance perspective."
"some exposure concentration-dependent changes in tissue Cu and Zn levels were observed, especially in the brain. Exposure to TiO2 NPs caused statistically significant decreases in Na+K+-ATPase activity (ANOVA, P < 0.05) in the gills and intestine, and a trend of decreasing enzyme activity in the brain (the latter was not statistically significant). Thiobarbituric acid reactive substances (TBARS) showed exposure concentration-dependent and statistically significant (ANOVA or Kruskal–Wallis test, P < 0.05) increases (two-fold or more) in the gill, intestine and brain, but not the liver during exposure to TiO2 NPs compared to controls. TiO2 NP exposure caused statistically significant (ANOVA, P < 0.05) increases in the total glutathione levels in the gills, but depletion of hepatic glutathione compared to controls... Liver cells exposed to TiO2 NPs showed minor fatty change and lipidosis, and some hepatocytes showed condensed nuclear bodies (apoptotic bodies)."
Sunlight can break up clusters of titanium dioxide nanoparticles to increase their transport into the skin, according to scientists from the University of California, US. Their study showed that sunlight reduced the size of nanoparticles.
"Considering the fact that nanoparticles are now used to help deliver nutrients, keep food fresh for longer, and act as thickening and coloring agents in processed foods, these 'different properties' might be cause for concern. Or — at the very least — they might be reason enough to conduct thorough research into their health impacts... As Tom Philpott observed in Grist in 2010, the last time big questions surfaced about nanotech in food in the media: 'As with GMOs, the strategy seems to be: release into the food supply en masse first; assess risks later (if ever).'"
The toxicity of ENMs can be significantly different from that of conventional materials, even when the two materials have the same chemical composition.
Nicnas found that nanotubes should be classified as having “specific target organ toxicity following repeated exposure Category 2” and carry the warning “May cause damage to lungs/respiratory system through prolonged or repeated inhalation exposure” as well as Carcinogen Category 2, “suspected of causing cancer”.
"Studies show that nanoparticles can easily penetrate DNA and the cells of the lungs, skin and digestive system, thereby causing harm to living organisms (2)... Nanoparticles are also now being engineered to be more resilient, thereby increasing the risk of causing irreversible damage to living organisms. We simply do not have sufficient data or risk assessment laws in place to analyse whether nanoparticles are safe for consumption."
"The information in the database is intended to form the basis of an evaluation of whether the content of nanomaterials in products on the Danish market poses a risk for consumers and the environment. The Ministry plans for the first reports to be due in early 2014."
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"The report points out that nanotechnology development has occurred in the absence of “clear design rules for chemists and materials developers on how to integrate health, safety and environmental concerns into design.” While the emerging area of ‘green nanotechnology’ offers promise for the future with its focus on preventive design, it is important that research on the sustainability of materials is funded at levels significant enough to identify early warnings and potential harms, and that regulatory systems provide incentives for safer and sustainable materials. Regulators and policy-makers have yet to address many of the shortcomings in legislation, research and development, and limitations in risk assessment. EEA concludes that as a result, “There remains a developmental environment that hinders the adoption of precautionary yet socially and economically responsive strategies in the field of nanotechnology. If left unresolved, this could hamper society’s ability to ensure responsible development of nanotechnologies.” Recently, EPA announced plans to obtain information on nanoscale materials in pesticide products and to register nanoscale materials as new active pesticide ingredients. The agency stated it will gather information on nanoscale materials present in pesticide products to determine whether the registration of the pesticide product may cause unreasonable adverse effects on the environment and human health."
Leading scientists are calling for the regulation of nano-particles in consumer goods until we better understand their longer-term impacts on human health and the environment.
"The toxicity of gold nanoparticles (AuNPs) varies significantly with size according to studies at the Joint Research Centre (JRC) in Ispra, Italy... The study showed the total gold content in the cells to increase steadily with exposure time, while nanoparticles did not reach the cell nucleus, but were confined in vesicles within the cell."
"The offspring of pregnant mice exposed to titanium dioxide nanoparticles may have reduced sperm counts and take longer to have their first litter, according to a Danish study."
"However, as the potential uses of SiNPs have increased, research looking into the biological effects and toxicity has not kept up to speed. Studies have shown that inhalation of microcrystalline silica may be linked with the pulmonary disease silicosis in humans. Chronic inhalation studies in rats have been associated with pulmonary fibrosis and cancer, and exposure to microscale amporphous silica has been linked to inflammation, granuloma formation and emphysema. A complete understanding of the size, shape, and composition-dependent interactions of SiNPs with biological systems is lacking, largely due to suitable analytical methods. The Livermore PK analysis showed that SiNPs were rapidly cleared from the circulatory system (the "central compartment" in PK models) and were distributed to various body tissues, where they persisted over the eight-week time course of the study, raising questions about the potential for bioaccumulation and associated long-term effects."
“Nanotechnology and nanomaterials used in the development of these products improve our everyday lives, but it is important that we understand how humans are exposed to nanomaterials and to assess the risks they may pose to people’s health and the environment,” said Dr. Tina Bahadori, national program director for EPA’s Chemical Safety for Sustainability Research.
"Currently, USDA organic certified products are the last refuge for consumers wanting to [avoid] nanomaterials... Overall, little is being done to review, regulate, or safety test nanotechnology that is currently being used in agriculture and food processing, ingredients and packaging."
"Our food supply is not nearly as safety-tested as we would like to believe... Unbeknownst to just about everyone, nanoparticles made a quiet entrance into the nation’s food supply at least a decade ago... 'At the moment, there is not much information available on the topic of ingested nanoparticles and human health,' says Birgit Gaiser, Ph.D., a postdoctoral research fellow at Heriot-Watt University in the UK... The FDA has been slow to catch up. In fact, the agency doesn’t even track which foods contain nanoparticles."
But it is common that many food and dietary supplements manufacturers use nanoparticles like titanium dioxide, silicon dioxide and zinc oxide in foods and dietary supplements. Titanium dioxide is not the only nanomaterial that is toxic. Because the toxicity of nanoparticles is largely caused by the particles' sizes, the toxicity observed with titanium dioxide can also be applicable to other nanoparticles like zinc oxide and silicon dioxide. A study recently published in Nanotoxicology shows that zinc oxide (ZnO) nanoparticles may be even more toxic than titanium dioxide (TiO(2)).
“As with any emerging technology or novel material, the scarcity of exposure and effect data introduces potentially high uncertainty into the characterisation of nanomaterials risk,” say the researchers. “Future priorities will include not only the generation of new exposure and hazard data, but also the application of suitable approaches and methods to support future decisions on nanomaterials risk.”
"Manufactured metal (oxide) nanoparticles are entering the aquatic environment with little understanding on their potential health impacts for exposed organisms. Adopting an integrative approach, we investigated effects of particle size and coating on biological responses for two of the most commonly used metal (oxide) nanoscale particles, silver (Ag) and titanium dioxide (TiO2) in zebrafish embryos... Ag both in nano form (10 nm and 35 nm) and its larger counterpart (600–1600 nm) induced dose-dependent lethality and morphological defects, occurring predominantly during gastrula stage. Of the silver material tested 10 nm nanoparticles appeared to be the most toxic... Collectively, our data suggest that silver ions play a major role in the toxicity of Ag nanoparticles."
New research shows that the protective coating on titanium dioxide nanoparticles, a common component of sunscreen lotions, degrades in swimming pool water and forms dangerous reactive oxygen species.
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