Fathead minnow toxicity

Partial least squares (PLS) is similar to MLR in that it also assumes a linear relationship between a vector x and a target property y. However, it avoids the problems of collinear descriptors by calculating the principal components for the molecular descriptors and target property separately. The scores for the molecular descriptors are used as the feature vector x and are also used to predict the scores for the target property, which can in turn be used to predict y. An important consideration in PLS is the appropriate number of principal components to be used for the QSAR model. This is usually determined by using cross-validation methods like fivefold cross validation and leave-one-out. PLS has been applied to the prediction of carcinogenicity [19], fathead minnow toxicity [20], Tetrahymena pyriformis toxicity [21], mammalian toxicity [22], and Daphnia magna toxicity [23],... 

When considering environmental chemicals, another important measure of toxicity is based on the EPA acute fathead minnow toxicity database. In this assay, 28-36-day-old fathead minnows are exposed to varying concentrations of a test molecule in a flow-through apparatus for 96 h [56], The concentration of the organic chemical that produced 50% lethality (LD50) was reported in the EPA database. The median LD50 from 586 molecules was 21.5 mg/1. This value could comprise another cutoff in a computational alert. 

TAFT SIGMA AND SIGMA, CONSTANTS IMPROVE LOG OCTANOL/WATER PARTITION COEFFICIENT BASED OSAR FOR FATHEAD MINNOW TOXICITY... 

Environmental Concerns. Few data on the environmental effects of the nitroparaffins are available. However, they are known to be of low toxicity to the fathead minnow (109). Based on their uv spectra, the nitroparaffins would be expected to undergo photolysis in the atmosphere. The estimated half-life of 2-nitropropane in the atmosphere is 3.36 h (110). Various values have been determined for the half-life of nitromethane, but it is similar to 2-nitropropane in persistence (111). Reviews of the available data on the environmental effects of nitromethane and 2-nitropropane have been pubhshed by the U.S. Environmental Protection Agency (112,113). 

The chronic aquatic effects which relate silver speciation to adverse environmental effects were studied on rainbow trout eggs and fry. The maximum acceptable toxicant concentration (MATC) for silver nitrate, as total silver, was reported to be 90—170 ng/L (43). Using fathead minnow eggs and fry, the MATC, as total silver, for silver thiosulfate complexes was reported as 21—44 mg/L, and for silver sulfide as 11 mg/L, the maximum concentration tested (27). 

Aquatic toxicity is reported in mg/L for Pimepha/espromealas (fathead minnow), 69-h LC q 7650 (17) for Daphnia magna (water flea), 48-h EC q 3310 (18) for Mjriophjllum spicatum (water milfoil), phytotoxicity (EC q for growth) 5962 (19) and for Pana breviceps (frog), no observed effect concentration (NOEC) 400 (20). LC q and EC q are lethal and effect concentrations, respectively, for 50% of the subjects tested. 

Both acute and chronic toxicity testing of the treated effluent on daphnia shrimp and fathead minnows have indicated that the effluent is completely suitable for discharge into receiving waters with no adverse impact (42). 

Ward TJ, Kowalski PL, Boeri RL (1995c) Acute toxicity of the water accommodated fraction (WAF) of aikyitin MA to the fathead minnow, Pimephales promelas. Marblehead, MA, T.R. Wilbury Laboratories, Inc. (Study No. 861-MO). 

Organophosphate Ester Hydraulic Fluids. Very little information on the food chain bioaccumulation of organophosphate ester hydraulic fluids is available. It is known that some organisms bioconcentrate components of organophosphate ester hydraulic fluids (values are 133-2,807 for rainbow trout and 596-928 for fathead minnows) (Lombardo and Egry 1979 Mayer et al. 1981 Muir et al. 1983a Veith et al. 1979). Given the concerns over the toxicity of this class of hydraulic fluids, further research on this topic would be useful. 

Broderius SJ, Smith LL Jr, Lind DT. 1977. Relative toxicity of free cyanide and dissolved sulfide forms to the fathead minnow (Pimephales promelas). Journal of the Fisheries Research Board of Canada 34 2323-2332. 

TEST allows for estimates of the value for several toxicity endpoints [29] 96 h Fathead minnow LC50, 48 h Daphnia magna LC50, 48 h Tetrahymena pyriformis IGC50, Oral rat LD50, bioaccumulation factor, developmental toxicity, and Ames mutagenicity. TEST also estimates several physical properties... 

Lazar (http //lazar.in silico.de/predict) is a k-nearest-neighbor approach to predict chemical endpoints from a training set based on structural fragments [43]. It derives predictions for query structures from a database with experimentally determined toxicity data [43]. Model provides prediction for four endpoints Acute toxicity to fish (lethality) Fathead Minnow Acute Toxicity (LC50), Carcinogenicity, Mutagenicity, and Repeated dose toxicity. 

Aquatic toxicity Daphnia magna 48 h LC50 and fathead minnow (fish) 96 h LC50... 

Lazar [59] derives predictions for four endpoints Fathead Minnow Acute Toxicity (LC50), Carcinogenicity, Mutagenicity, and Repeated dose toxicity. 

Finally, the Aquatic Toxicity module predicts fish and daphnia toxicity providing LC50 values (mg/L) for Pimephales promeals (Fathead minnow) and Daphnia magna (Water flea). Experimental values (if present) and similarity to test compound are shown for the five most similar structures from the training set [65]. 

Carlson, A.R., Kosian, P.A. (1987) Toxicity of chlorobenzenes to fathead minnows (pimephales promelas). Arch. Environ. Contam. Toxicol. 16, 129-135. 

Pickering, Q.H. and M. Gast. 1972. Acute and chronic toxicity of cadmium to the fathead minnow (Pimephales promelas). Jour. Fish. Res. Board Canada 29 1099-1106. 

In fishes, additive or more-than-additive toxicity occurs with mixtures of salts of copper and mercury, copper-zinc-phenol, and copper-nickel-zinc (Birge and Black 1979). Accumulation of copper in gills of fathead minnows during exposure to 16 pg Cu/L is reduced by added ionic calcium, which competes with Cu for gill binding sites (Playle et al. 1992). 

Hickie, B.E., N.J. Hutchinson, D.G. Dixon, and P.V. Hodson. 1993. Toxicity of trace metal mixtures to alevin rainbow trout (Oncorhynchus mykiss) and larval fathead minnow (Pimephales promelas) in soft, acidic water. Canad. Jour. Fish. Aquat. Sci. 50 1348-1355. 

Parrott, J.L. and J.B. Sprague. 1993. Patterns in toxicity of sublethal mixtures of metals and organic chemicals determined by Microtox and by DNA, RNA, and protein content of fathead minnows (Pimephales promelas). Canad. Jour. Fish. Aquat. Sci. 50 2245-2253. 

Pickering, Q.H. 1974. Chronic toxicity of nickel to the fathead minnow. Jour. Water Pollut. Contr. Feder. 46 760-765. 

Silver ion (Ag+) was the most toxic chemical species of silver to fishes. Silver ion was 300 times more toxic than silver chloride to fathead minnows (Pimephales promelas), 15,000 times more... 

Bury, N.R., F. Galvez, and C.M. Wood. 1999a. Effects of chloride, calcium, and dissolved organic carbon on silver toxicity comparison between rainbow trout and fathead minnows. Environ. Toxicol. Chem. 18 56-62. 

Karen, D.J., D.R. Ownby, B.L. Forsythe, T.P. Bills, T.W. La Point, G.B. Cobb, and SJ. Klaine. 1999. Influence of water quality on silver toxicity to rainbow trout (Oncorhynchus mykiss), fathead minnows (Pimephales promelas), and water fleas (Daphnia magnet). Environ. Toxicol. Chem. 18 63-70. 

Nebeker, A. V, C.K. McAuliffe, R. Mshar, and D.G. Stevens. 1983. Toxicity of silver to steelhead and rainbow trout, fathead minnows and Daphnia magna. Environ. Toxicol. Chem. 2 95-104. 

Brungs, W.A. 1969. Chronic toxicity of zinc to the fathead minnow, Pimephales promelas Rafinesque. Trans. Amer. Fish. Soc. 98 272-279. 

Dawson, D.A., E.F. Stebber, S.L. Burks, and J.A. Bantle. 1988. Evaluation of the developmental toxicity of metal-contaminated sediments using short-term fathead minnow and frog embryo-larval assays. Environ. Toxicol. Chem. 1 27-34. 

Hobson, J.F. and W.J. Birge. 1989. Acclimation-induced changes in toxicity and induction of metallothionein-like proteins in the fathead minnow following sublethal exposure to zinc. Environ. Toxicol. Chem. 8 157-169. 

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