Organochlorine and mercury residues in the harp seal (Pagophilus groenlandicus)

Mercury and Selenium Levels at the Fetal and Suckling Stages of Striped Dolphin,Stenella coeruleoalba

“…l l ) In rats, the ratio of the methylmercury content of infants just after birth to that of their mothers was approximately 10%.17) The ratio of the methylmercury burden of the full term striped dolphin fetus to that of pregnant females was remarkably low compared with that of the experimental animals. Our observation that the tissue concentration of mercury was lower in fetuses than in mature individuals is consistent with the results observed for harbour seals/ 8 ) harp seals 12 ) and gray seals. 19 ) The concentrations of methylmercury in the blood of striped dolphin fetuses and sucklings were 15 and 13 %, respectively, of those of the mature females as shown in Tables I, II and III.…”

“…Although half and most of the tissues at the suckling stage showed a decrease of mercury and an increase of selenium, respectively, as compared with the fetal stage, these changes appear to be associated with changes in the milk. The lower level of mercury in the milk of striped dolphins is consistent with the results for harp seals 12 ) and fur seals.13) However, our results are inconsistent with a rapid increase of the mercury level observed in the blood of the latter two seal species at the suckling stage.…”

Transplacental Transfer of PCBs and Chlorinated Hydrocarbon Pesticides from the Pregnant Striped Dolphin (Stenella coeruleoalba) to Her Fetus

“…In addition, parturition and lactation, although confined to adult females, should be considered as significant elimination routes of chlorinated hydrocarbons from their bodies. It has been recognized that the chlorinated hydrocarbon concentrations in the blubber of some marine mammals were lower in The transplacental transfer of chlorinated hydrocarbons has been suggested in seals, 4,6,18,19) but little is known in regard to their transfer rates and mechanisms through parturition. We have estimated the elimination rates of chlorinated hydrocarbons such as PCBs, p,p' -DDT, p,p' -DDE, p,p' -DDD, HCH (1,2,3,4,5,including iX, p and y isomers) and HCB (Hexachlorobenzene) from the pregnant striped dolphin through parturition, and also discussed the partitioning characteristics of chemicals and the role of blubber, blood and placenta relevant to the transplacental transfer.…”

Sharp accumulation of heavy metals after weaning in the South American fur seal Arctocephalus australis

“…Detectable milk transfer of mercury and a very limited transfer of cadmium were also reported in harp seals Pagophilus groenlandicus (Jones et al 1976, Wageman et al 1988) and harbour seals Phoca vitulina (Drescher et al 1977). The contrasting contribution of both metals via milk and placenta in South American fur seals is confirmed by the levels recorded in WP and SP.…”

“…Placental transfer of methylated forms of mercury to fetuses has been reported for harp seals Pagophilus groenlandicus (Jones et al 1976, Drescher et al 1977, Wagemann et al 1988) and other mammal species (Wolfe et al 1998), and appears to be responsible for the initial fetal mercury burden found in several marine mammals. No evidence of placental transfer of cadmium has been found in South American fur seal pups, which is in agreement with previous results in several dolphin species (Honda & Tatsukawa 1983, Law et al 2003.…”