Three Purdue researchers recently published the results of a NSF sponsored study on the environmental effects of fullerenes on microbial communities in digestor sludge samples taken from the Greater Lafayette Wastewater Treatment Plant.

L. Nyberg, et al., "Assessing the Impact of Nanomaterials on Anaerobic Microbial Communities," 42 Environ Sci. Technol. 6, at 1938-1943 (2008).

The researchers hypothesized that the release of fullerenes into wastewater discharge is likely to occur as nanotechnology is commercialized.  Further, because anaerobic sludge at wastewater treatment facilities contains a host of important living organisms, the group believes that "microbial communities in anaerobic digestors are excellent sentinel communities for evaluation of the effects of" fullerenes.

The study measured methanogenesis [methane production] of sludge samples exposed to fullerenes for several weeks (up to 89 days).  "Gas production data showed no toxicity due to any fullerene treatment.  Nor was biodegradation of C60 indicated by an increase in gas formation."

Despite these positive results, the scientists cautioned that "[l]ong-term studies of microbial communities will be required to determine the overall environmental impact of fullerenes. The time frame for evolution of biodegradation of a new chemical in anaerobic systems may be particularly long, so it is too early to conclude that microbial ecosystems and biogeochemical cycles will be unaffected by C60."