Poecilia fishes

The effects of EDCs on behavior in fish have been more extensively studied than in birds. Examples of the effects of EDCs seen in fish include profound alterations in courtship behavior in male guppies (Poecilia reticulate) exposed to vinclozolin and DDE, including at environmentally relevant concentrations (Baatrup and Junge 2001) and altered courtship behavior in three-spined stickleback exposed to environmentally relevant concentrations of EE2 (Bell 2001). In the stickleback studies, exposed males became less aggressive and had a reduced nesting activity, and this was linked with reduced concentrations of the male sex androgen 11-ketotestosterone. Recently,... 

Pre-exposure to the organophosphate diazinon at exposures half the LC50 values increased the LC50 value by a factor of about five for guppy (Poecilia reticulata), but had no effect on the value for zebra fish (Brachydanio rerio). This was consistent with the observation that during pre-exposure of guppy there was a marked inhibition in the synthesis of the toxic metabolites diazoxon and pyrimidinol, whereas this did not occur with zebra fish in which the toxicity was mediated primarily by the parent compound (Keizer et al. 1993). 

Other Organisms Tested with Aponin. It is probably impossible to satisfy all persons interested in the effect of aponin or other organisms because the range of potentially affected organisms is so great. Nevertheless a number of organisms have been tested. We tested fish which were adapted to salt water (Poecilia sphenops)... 

Pierson, K.B. 1981. Effects of chronic zinc exposure on the growth, sexual maturity, reproduction, and bioaccumulation of the guppy, Poecilia reticulata. Canad. Jour. Fish. Aquat. Sci. 38 23-31. 

Keizer, J., G. D Agostino, and L. Vittozzi. 1991. The importance of biotransformation in the toxicity of xenobiotics to fish. I. Toxicity and bioaccumulation of diazinon in guppy (Poecilia reticulata) and zebra fish (Brachydanio rerio). Aquat. Toxicol. 21 239-254. 

LC50 (96-h) for bluegill sunfish 250 jg/L (Spehar et al., 1982), mosquito fish Gambusia affini 0.80 pmol/L (Chaisuksant et al., 1998) for Poecilia reticulata 135 pg/L (van Hoogen and Opperhuizen, 1988), Gyprinodon variegatus 800 ppb using natural seawater (Heitmuller et al, 1981). 

Figure 10.13 Plot of log 1/LC,S0 for guppies (small tropical fish, Poecilia reticulata) versus (a) log octanol-water partition constant (log A ,ow), and (b) log L-a-dimyristoylphosphatidylcholine liposome-water coefficient (log A)]ipsw) for a series of neutral apolar and weakly polar (o) and polar (t) compounds. Data from Gobas et al. (1988), Vaes et al. (1998), and Gunatilleka and Poole (1999).

Sijm et al. (1993) determined LBBi and 96h- LCiS0 values of a series of chlorinated benzenes in guppies (Poecilia reticulata). The fish had an average weight of 0.18 g w.w. and a total lipid content of about 5% w.w. For 1,2,3-trichlorobenzene (TrCB) the LBBf values found were 2.7,2.0, and 2.4 mmol kg-1 w.w. for exposure to 5.6, 3.8, and 1.9 jumol TrCB -L"1, respectively. The death of the fish occurred after 2.4, 24, and 96 hours. Note that similar LBBi values (2-8 mmol-kg 1 w.w.) were found for the other compounds. The 96 h LC(50 value of TrCB was determined to be 1.9 /unol-L"1. 

Reinert, R.E. 1972. Accumulation of dieldrin in algae (Scenedesmus obliquus), Daphnia magna, and the guppy (Poecilia reticulata). J. Fish. Res. Bd. Can. 29 1413. 

The metabolism of PCDEs in fish has not been studied much, but apparently the metabolism in fish is low and similar to that of PCBs. Hydroxy-PCDEs were not detected in guppy (Poecilia reticulata) exposed to tri- and tetraCDEs [63]. Low metabolism and slow excretion leads to persistence and bioaccumulation. According to a study of Zitko and Carson [109], tri- through pentaCDEs are somewhat more persistent in fish than the corresponding PCBs. The excretion half-lives of one trichloro (PCDE 28 2,4,4 -), one tetrachloro (PCDE 66 2,3, 4,4 -) and one pentachloro (PCDE 99 2,2, 4,4, 5-) were 15,55, and 55 days in juvenile Atlantic salmon (Salmo salar), respectively. Half-lives of PCDEs were near to those of PCBs. The depuration half-lives of mono- through tetraCDEs have varied from 4 to 63 days in brook trout (Salvelinus fontinalis) [83] and those of tri- through decachlorinated PCDEs between 46 and 100 days in rainbow trout (Salmo gairdneri) [110]. 

Khudolei, V.V. The use of the aquarium fishes Danio rerio and Poecilia reticulata as highly sensitive species for testing the carcinogenicity of chemical compounds. Eksp. Onkol. 9 40-46, 1987. 

Khudoley, V.V. Use of aquarium fish, Danio rerio and Poecilia reticulata, as test species for evaluation of nitrosamine carcinogenicity. Natl Cancer Inst. Monogr. 65 65-70, 1984. 

Schafers, C. and R. Nagel. 1991. Effects of 3,4-dichloroaniline on fish populations. Comparison between r- and K-strategists a complete life cycle test with the guppy (Poecilia reticulata). Arch. Environ. Contam. Toxicol. 21 297-302. 

---