Scientists at the Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, have generalized the known facts about the influence of technogeneous nanoparticles on water-dwelling organisms. The report published in the Newsletter of Russian Academy of Sciences, the Biological Series, showed that the presence of nanoparticles in water negatively affected hydrocoles; the researchers noted, however, that there still was insufficient information to draw final conclusions.

Nanoparticles are objects the size of which in at least one dimension does not exceed 100 nanometer. They can be of carbon or metal origin; they can be made of metal oxide; or they can present semiconductors, organic polymers, etc. Nanoparticles were put into a single category as their small size itself leads to uncommon physical and chemical properties. Nanoparticles usually feature high penetrating power, large surface area and chemical activity.

The researches show that nanoparticles can penetrate organisms of animals and humans through skin coverings, via accidental inhaling, or with water and food. Water-dwelling organisms are most affected by nanoparticles, believe the scientists. Nanoparticles get into the bronchia and digestive tract of water dwellers and can possibly move along the food chains — for example, from maxillopoda to fish — and accumulate in the organisms positioned on the upper steps of the food pyramid.

Nanoparticles can be toxic for organisms due to their size and physical and chemical properties. The presence of nanoparticles in the water decreases the fertility of hydrocoles; causes various physiological changes, behaviour disorders and increased death rate. The toxicity is influenced by the size of the particles, their chemical nature, water solubility. It is a known fact that nanoparticles of zinc oxide, copper oxide and silver oxide are more toxic as compared to the nanoparticles of other metals and metal oxides. The researchers note, however, that the data on nanomaterial toxicity is quite controversial and ambiguous — for example, the effects of chronic nanoparticle influence are virtually unexplored.

The scientists note that the development of nanotechnologies is mush ahead of the assessments of their influence on the environment. Therefore, all issues associated with the behaviour of nanomaterials in the environment and their influence on living organisms and ecosystems require great attention and serious systematic research.

Further information: Evgeny Krysanov, Ph. D. (Biology), senior staff scientist, the Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow; (499)135-7218, krysanov@sevin.ru    

Source of information: Е. Yu. Krysanov, D. S. Pavlov, T. B. Demidova, Yu. Yu. Dgebuadze: “Nanoparticles in the Environment and their Influence on Hydrocoles.” Newsletter of Russian Academy of Sciences. The Biology Series, 2010, #4