Chlorinated Organic Contaminants in Blubber Biopsies from Northwestern Atlantic Balaenopterid Whales Summering in the Gulf of St Lawrence

Abstract:

Concentrations and patterns of chlorinated biphenyls (CBS) and other persistent organochlorine compounds (OCs) were determined from small blubber biopsy samples collected from northwestern Atlantic minke (Balaenoptera acurostrata) , fin (Balaenoptera physalus), blue (Balaenoptera musculus) , and humpback (Megaptera novaeangliae) whales summering in the Gurf of St. Lawrence, Quebec. Concentrations of CPCB (sum of 19 congeners) in biopsy samples ranged from 0.2-10 pg g-’ lipid, and congeners 52, 101, 118, 153, 138 and 180 accounted for 79% of CPCB. Mean concentration of the sum of nonortho CB congeners in selected biopsy samples was 2 ng g-t lipid, and relative concentrations of these analytes were: 77 > 126 > 81> 169. Concentrations of XDDT ranged from 0.613 pg g-t lipid, and the average proportion of DDE to CDDT was 72%. All other organochlorine analytes were present at concentrations below 2 pg g-t lipid. On average, cis-nonachlor, trans-nonachlor and oxychlordane accounted for 27, 26 and 23%, respectively, of the chlordane-related analytes, and cl-hexachlorocyclohexane (HCH) comprised 67% of XHCH. Concentrations of CDDT were signtficantly lower and mirex concentrations were significantly higher in minke whales than in the other balaenopterid species. Concentrations of all other analytes were similar in the four whale species. Ratios of proportions of oxychlordane to trans-nonachlor were highest in fin whales. Blue whales had the lowest proportions of u-HCH but the highest proportions of DDT. Interspecies diflerences in the concentrations and patterns of certain CB congeners and OC compounds may reject d@erences in diet or in metabolic capabilities. Males usually had higher mean concentrations of CBS and OCs than females, but these differences were sign$cant only for CDDT, dieldrin, CHCH and HCB. Higher proportions of lower chlorinated CB congeners were found in calves compared to adult females, indicating selective reproductive transfer.

Gauthier, J.M., C.D. Metcalfe and R. Sears. 1997. Chlorinated Organic Contaminants in Blubber Biopsies from Northwestern Atlantic Balaenopterid Whales Summering in the Gulf of St Lawrence. Marine Environmental Research. 44(2):201-223.
Chlorinated Organic Contaminants in Blubber Biopsies from Northwestern Atlantic Balaenopterid Whales Summering in the Gulf of St Lawrence PDF (1.75 MB)