Relation between the content of organochlorine compounds in Finnish human milk and characteristics of the mothers.

Neutral organochlorine pesticide and PCB residues were analyzed by GC-MS technique in 183 human milk samples obtained in 1984-1985 from 165 women living in different parts of Finland. The effect of the donors' age, body mass, place of residence, number of children, dietary habits, smoking habits, occupational history, and weight loss on the organochlorine content of human milk were studied. Of all the milk samples analyzed, p,p'-DDE concentrations were above the detection limit in 99.5%, p,p'-DDD + p,p'-DDT in 57.9%, isomers of HCH in 30.0%, cis-chlordane in 4.9%, oxychlordane in 3.3%, trans-nonachlor in 6.0%, heptachlor in 12.0%, and heptachlor epoxide in 6.6%. Mirex was not found in any of the milk samples, whereas the signals of chlorinated terpenes (toxaphenes) were detected but could not be quantitatively determined. The mean fat adjusted residue levels above the detection limit in Finnish human milk samples of primipara mothers were 0.66 ppm for total DDT compounds, 0.08 ppm for HCB, 0.93 ppm for PCBs, 0.41 ppm for chlordane compounds, 0.20 ppm for isomers of HCH, and 0.10 ppm for heptachlor epoxide. The geometric means were 0.46, 0.06, 0.57, 0.02, 0.02, and 0.01 ppm, respectively. The age of the mothers positively correlated with the DDE concentrations in human milk. The residues of OC compounds in human milk did not differ in women living in plywood industry regions, those actually working in the industry, and other mothers. Small differences were detected in the levels of organochlorine compounds in different parts of Finland. No relation was found between the OC content and the fish consumption, smoking habits, weight loss, or social group of the donors.