Highly chlorinated dimethanofluorenes in technical chlordane and in human adipose tissue

Several new components of technical chlordane were discovered using electron capture, negative ionization gas chromatographic mass spectrometry. These compounds have 10-12 chlorines and are produced by the condensation of three cyclopentadiene molecules. The most abundant compound has a molecular weight of 606 and has the elemental composition C15H6Cl12. This compound and a series of related compounds were also identified as contaminants in human adipose tissue samples. These compounds are approximately 0.01-0.03% of the technical chlordane mixture, and they have average concentrations in human adipose tissue of 0.4-0.7 ng per gram of fat. They are more highly retained in human adipose tissue than chlordane-like compounds containing eight or fewer chlorine atoms.