Fullerenes in environmental samples: C ₆₀ in atmospheric particulate matter

Combustion processes can form fullerenes (C ₆₀). Therefore we investigate the occurrence of C ₆₀ in various atmospheric environments. The detection and quantification is achieved with the highly specific and sensitive method of liquid chromatography coupled to mass spectrometry following solvent extraction of the samples. C ₆₀ was detected in the air particulates of a parking garage and the exhaust soot of a diesel truck. These results would indicate that fullerenes are incidentally produced from combustion processes and become associated with atmospheric particulate matter. However C ₆₀ is susceptible to atmospheric oxidation processes. In particular ozonation tests on solid C ₆₀ confirm the production of fullerene-based compounds such as C ₆₀O. Such oxidation and alteration of the molecular structure of the fullerenes would explain the low ambient concentrations observed respectively the inability to detect C ₆₀ in ambient air in many locations, further away from potential emission sources. These results have significant policy implications including considering incidental sources of C ₆₀ in addition to engineered C ₆₀ added to commercial products, and understanding environmental oxidation processes for C ₆₀ in conjunction with quantifying transformation products.