Nanotubes and lead: lethal combination
Nanomaterials may be detrimental to water quality and the environment, warned Diego Stéfani Martinez, researcher at the Solid State Chemical Laboratory (LQES) of the Chemistry Institute (IQ) at the University of Campinas (Unicamp), during a November 2012 conference in France on nanomaterials safety. As a result of experiments conducted on tilapias exposed to variable concentrations of carbon and lead nanotubes for up to 96 hours, Martinez and other LQES researchers along with researchers from the São Paulo Fisheries Institute, in the city of Cananeia, found that nanotubes may cause a fivefold increase in acute toxicity to lead in certain species of fish (see Journal of Physics: Conference Series, March issue). Nanotubes themselves show no signs of acute toxicity up to a concentration of 3 milligrams per liter, but they apparently caused reduced oxygen intake and a discharge of ammonia in the fish. The study’s authors call attention to the implications nanomaterials have on aquatic environments, as well as their interactions with everyday pollutants like lead.