Biological accumulation of engineered nanomaterials

(Nanowerk News) Due to the widespread use of engineered nanomaterials (ENMs) in consumer and industrial products, concerns have been raised over their impacts once released into the ecosystems. While there has been a wealth of studies on the short-term acute toxic effects of ENMs over the past decade, work on the chronic endpoints, such as biological accumulation, has just begun to increase in last 2–3 years.
A new report, published in the December 17, 2012 online edition of Environmental Science: Processes & Impacts ("Biological accumulation of engineered nanomaterials: a review of current knowledge"; free access with registration), comprehensively reviews over 65 papers on the biological accumulation of ENMs under a range of ecologically relevant exposure conditions in water, soil or sediment with the focus on quantitative comparison among these existing studies.
The rseearchers found that daphnid, fish, and earthworm are the most commonly studied ecological receptors. Current evidence suggests that ENM accumulation level is generally low in fish and earthworms with logarithmic bioconcentration concentration factor and biotasediment accumulation factor ranging from 0.85–3.43 (L kg-1) and 2.21–0.4 (kg kg-1), respectively.
ENMs accumulated in organisms at the lower trophic level can transfer to higher trophic level animals with the occurrence of biomagnification varying depending on the specific food chain studied. The authors conclude the review by identifying the challenges and knowledge gaps and propose paths forward.
Source: Royal Society of Chemistry