title: Bioconcentration factor of relatively low concentrations of chlorophenols in Japanese medaka.
abstract: Bioconcentration factors (BCF) for pentachlorophenol (PCP) and 2,4-dichlorophenol (2,4-DCP) in Japanese medaka (Oryzias latipes) were determined at five different concentrations of the chemicals, between 0.1 and 10 microg/l (PCP), 0.3 and 30 microg/l (2,4-DCP), in the ambient water. Medaka were exposed to each chemicals in a continuous-flow system during the embryonic development period and 60 days after hatching from eggs collected in the laboratory. Both the exposure time and the aqueous concentrations are much more realistic and closer to natural aquatic environments than those used in conventional BCF studies. The BCF values of PCP were from (4.9+/-2.8)x10(3) at the aqueous concentration of 0.074+/-0.028 microg/l to (2.1+/-1.4)x10(3) at 9.70+/-0.56 microg/l. The BCF value of 2,4-DCP were from (3.4+/-3.0)x10(2) at 0.235+/-0.060 microg/l to 92+/-27 at 27.3+/-1.6 microg/l. Generally, BCF values increased as the aqueous concentrations of PCP or 2,4-DCP decreased. This finding suggests that a relatively low and realistic aqueous concentration of these compounds is necessary to more accurately determine their BCF values in natural aquatic environments. Conventional BCF experiments at higher aqueous concentrations may underestimate the BCF values.
authors.affiliation: National Inst. for Environ. Studies, 16-2 Onogawa, Tsukuba City, Ibaraki 305-8506, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Kondo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Norihisa
authors.initials: N
authors.lastname: Tatarazako
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kawabe
authors.forename: Masaaki
authors.initials: M
authors.lastname: Koshio
authors.forename: Narisato
authors.initials: N
authors.lastname: Hirai
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Morita
mesh_terms: D000818:Animals; D002733:Chlorophenols / Q000032:analysis / Q000493:pharmacokinetics*; D004784:Environmental Monitoring; D007564:Japan; D009990:Oryzias; D010416:Pentachlorophenol / Q000032:analysis / Q000493:pharmacokinetics*; D014018:Tissue Distribution; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics*
chemical_list: D002733:Chlorophenols; D014874:Water Pollutants, Chemical; D010416:Pentachlorophenol; C004762:2,4-dichlorophenol