Organochlorine pesticide residues in Italian citrus essential oils, 1991-1996.

Organochlorine pesticide contamination in 148 lemon essential oils, 123 sweet orange oils, 121 mandarin oils, and 147 bergamot oils produced in Italy in the years 1991-1996 was studied by HRGC-ECD. Confirmation analyses were carried out by GC-MS. Tetradifon, dicofol and its decomposition product 4,4'-dichlorobenzophenone were found. Over the course of the study dicofol and tetradifon residues steadily decreased; the percentage of contaminated samples reflects this course and decreases considerably from 1991 to 1996.