title: Differences in the acute toxicities of tributyltin between the Caprellidea and the Gammaridea (Crustacea: Amphipoda).
abstract: Tests for the acute toxicity of tributyltin (TBT) were conducted on amphipod crustaceans collected from Otsuchi Bay, Japan. Five species of caprellids and three species of gammarids, which belong to a closely related ecological niche, were used for the exposure experiments at seven test concentrations (0, 0.001, 0.01, 0.1, 1, 10 and 100 microg TBTCl/l) for 48 h at 20 degrees C. The 48-h LC50 values of the caprellids were 1.2-6.6 microg TBTCl/l, and these were significantly lower than those of the gammarids (17.8-23.1 microg TBTCl/l). This suggests that caprellids are more sensitive to TBT than gammarids. Furthermore, the proportions of TBT and its derivatives, dibutyltin (DBT) and monobutyltin (MBT), were measured in the amphipods collected from Otsuchi Bay. In the caprellids, TBT was the predominant compound, accounting for 72% of the total butyltin which reflected the butyltin ratio in seawater, while in the gammarids, TBT's breakdown products (DBT and MBT) predominated, accounting for 75% of the total butyltin. This difference suggests that caprellids may have lower metabolic capacity to degrade TBT than gammarids. Therefore, the difference in sensitivity to TBT among the amphipods is thought to be related to the species-specific capacity to metabolize TBT.
authors.affiliation: Otsuchi Marine Research Center, Ocean Research Institute, The University of Tokyo, Iwate, Japan. ohji@wakame.ori.u-tokyo.ac.jp
authors.forename: Madoka
authors.initials: M
authors.lastname: Ohji
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takeuchi
authors.forename: Shin
authors.initials: S
authors.lastname: Takahashi
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Tanabe
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Miyazaki
mesh_terms: D000818:Animals; D003445:Crustacea / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure; D005880:Gills / Q000378:metabolism; D012623:Seawater / Q000737:chemistry; D013045:Species Specificity; D014018:Tissue Distribution; D014220:Trialkyltin Compounds / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*
chemical_list: D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; C011559:tributyltin