Tris (4-chlorophenyl) methane and tris (4-chlorophenyl) methanol in marine mammals from the Estuary and Gulf of St. Lawrence

Abstract

Levels of tris (4-chlorophenyl) methanol (TCPM) and its presumed precursor tris (4-chlorophenyl) methane (TCPMe) are reported in marine mammals from the Estuary and Gulf of St. Lawrence, Canada. These compounds were measured in blubber samples of seals and whales using ion trap mass spectrometry (MS/MS) detection. Detectable concentrations of both TCPM and TCPMe were observed in all of the samples analysed. Concentrations of these compounds varied with species ranging from 1.7 to 153 and from 1.3 to 50.6 ng/g lipid wt. for TCPM and TCPMe, respectively. TCPM was from 1.3 to 10 times more concentrated than TCPMe. The highest levels of both TCPM and TCPMe were observed in adult male beluga whales ( Delphinapterus leucas) from the St. Lawrence Estuary, while adult female beluga whales from the same area showed levels similar to those in the seals examined. Among the four seal species investigated, TCPM and TCPMe levels were the highest in grey ( Halichoerus grypus) and hooded ( Cystophora cristata) seals, and lowest in harp seals ( Phoca groenlandica). Intermediate levels were found in harbour seals ( Phoca vitulina); however, their concentrations might be underestimated considering the younger mean age of these animals. Ratios of both 4,4′-DDE/ΣDDT and TCPM/ΣTCP were very similar between animals from the same species. Strong correlations between ΣTCP and ΣDDT were also observed for each species of mammals, most likely indicating that both ΣTCP and ΣDDT are bioaccumulated in marine mammals. The relationships between ΣDDT and ΣTCP also demonstrate that ΣTCP are less bioaccumulated than ΣDDT by the marine mammal species examined.