Accumulation of Butyltin Compounds in Risso's Dolphin (Grampus griseus) from the Pacific Coast of Japan:  Comparison with Organochlorine Residue Pattern

Abstract

Concentrations of butyltins (BTs) in the liver and organochlorine compounds (OCs) in the blubber of Risso's dolphins collected off Taiji, Japan, in 1991 were determined. Mean and range concentrations (wet weight basis) of these compounds were 3.6 μg/g (0.55−6.0 μg/g) for BTs, 25 μg/g (1.7−120 μg/g) for PCBs, 17 μg/g (0.45−77 μg/g) for DDTs, 4.0 μg/g (0.19−16 μg/g) for CHLs, and 0.16 μg/g (0.008−0.74 μg/g) for HCHs. OCs concentrations increased with age in males in contrast to that in females, which showed a decreasing trend after maturity. On the other hand, no difference was observed in BT concentrations between male and female, which showed increasing levels until maturity (8−10 years) and then remained constant. It is suggested that, unlike OCs, BTs were less transferable to young ones in reproductive processes. Risso's dolphins showed higher biomagnification factor (about 6) than Steller sea lion (0.6), implying a slower excretion rate of BTs in cetaceans than in pinnipeds due to the lower degradation capacity of xenobiotics and the lack of physiological processes such as shedding of hair in cetaceans.

Occurrence of synthetic musk fragrances in human blood from 11 cities in China

“…Thus, many women would have at least one baby when they were 26 to 40 years old. However, it was reported that mass transfer of accumulated lipophilic contaminants from mother to fetus would be a factor to influence the accumulation of organochlorines, dioxins, butyltin compounds [31][32][33], as well as synthetic musk fragrances [26]. Moreover, musks were verified detectable in a mother's milk [14].…”

Accumulation of butyltin compounds in dolphins stranded along the Mediterranean coasts

“…Many recent studies have focused on tissue concentrations and distribution of TBT and its metabolites in marine mammals. High concentrations have been reported in dolphins, [17][18][19][20] whales, 20 porpoises [21][22][23] and sea lions. 24,25 These studies have shown that TBT accumulates and is biomagnified by marine mammals, irrespective of sex; accumulation is generally greater in early life and the liver appears to be the organ where the highest concentrations are found.…”

Specific accumulation and elimination kinetics of tris(4-chlorophenyl)methane, tris(4-chlorophenyl)methanol, and other persistent organochlorines in humans from Japan.

“…As for CHLs, considerable enrichment of oxychlordane in bile also suggests the transformation of other chlordane compounds to oxychlordane and preferential excretion of this compound into bile. β-HCH was the most predominant isomer among HCHs; this pattern is usually observed in higher trophic animals such as marine mammals, indicating the persistence of this isomer toward enzymatic degradation (6,23,24). The slightly higher percentage of α-and γ-HCH in bile than in liver may suggest the excretable nature of less lipophilic organochlorines through bile.…”

“…All of these facts may account for the continuing high exposure to PCBs in Japanese humans. Our recent investigations have also indicated notable PCB pollution in marine mammals collected from various sites along the Japanese coastal waters (23)(24)(25). DDTs were the most abundant contaminants among OCs analyzed, with concentrations ranging from 160 to 8,100 (mean = 2,300) ng/g lipid weight in adipose tissue.…”

“…Unlike humans, marine mammals exhibited different age-and sex-dependent accumulation. Our earlier studies have demonstrated that OC accumulation in marine mammals increases with age in males, but in females residues remain relatively constant at lower levels after maturity (24,39,40). In marine mammals, significant transfer of OC burden through lactation in females may explain the substantial differences in accumulation pattern between males and females (41).…”