Sublethal effects of toxicants

Calabrese A, Thurberg FP, Dawson MA, WenzlofF DR. 1975. Sublethal physiological stress induced by cadmium and mercury in the winter flounder (Pseudoplumnectes amer-icanus). In Koeman JH, Strik JJ, editors, Sublethal effects of toxic chemicals on aquatic animals. Amsterdam Elsevier. 

Calabrese, A., F.R Thurberg, M.A. Dawson, and D.R. Wenzloff. 1975. Sublethal physiological stress induced by cadmium and mercury in winter flounder, Pseudopleuronectes americanus. Pages 15-21 in J.H. Koeman and J.J.T.W.A. Strik (eds.). Sublethal Effects of Toxic Chemicals on Aquatic Animals, Elsevier Sci. Publ. Co., Amsterdam. 

Leeuwangh, P., H. Bult, and L. Schneiders. 1975. Toxicity of hexachlorobutadiene in aquatic organisms. In J.H. Koeman and J.J.T.W.A. Strik (Eds.), Sublethal effects of toxic chemicals on aquatic animals. Proceedings of the Swedish-Netherlands Symposium, Wageningen, The Netherlands, September 2-5, 1975, Elsevier/North Holland Press, New York. pp. 167-176. 

Moriarty, F.M. (1968). The toxicity and sublethal effects of p-p -DDT and dieldrin to Aglais urticae and Chorthippus brunneus. Annals of Applied Biology 62, 371-393. 

No data were available on toxic or sublethal effects of lead to reptiles under controlled conditions. 

Considerable interest has developed concerning the nature of the mixed function oxidase system in fish and the role that this system may play in the development of toxic responses in these animals. Studies have shown that components of the mixed function oxidase system are present in relatively high concentrations in fish liver (4, 5, 6) and that the enzyme systems in this organ are capable of many of the biotransformation reactions already described for the mammalian liver (7, 8, 9). The presence of this complement of enzymes in the livers of many fishes suggests that this organ too may be particularly sensitive to insult from sub lethal concentrations of many waterborne toxicants. For this reason, methods to evaluate liver function in fish may be particularly useful in identifying the sublethal effects of certain classes of toxicants. 

Arunachalam, S Jeyalakshmi, K., and Aboobucker, S. Toxic and sublethal effects of carbaryl on a freshwater catfish, Mystus vittatus (Bloch), Arch. Environ. Contam. Toxicol, 9(3) 307-316, 1980. 

Sparling, D.W., Day, D., and Klein, P. Acute toxicity and sublethal effects of white phosphorus in mute swans, Cygnus olor, Arch. Environ. Contam. Toxicol, 36(3) 316-322, 1999. 

Again, the environmental and testing conditions for many wild mammalian and avian species are compatible with the domestic mammalian studies that have been done in some laboratories for years. Since some of the ecotoxicology studies concentrate on the nonlethal effects of the test substance on the test organisms, it is important that the test conditions and evaluation criteria be accurately described and the staff be very aware of sublethal effects of the toxicant on the test species. 

Observation of deaths of organisms and resultant declines in populations, though straightforward and unequivocal, are often insufficient to fully explain the effects of toxic substances on ecosystems. It is also important to consider sublethal effects, which may cause ill effects in populations without directly killing individuals. Exposure to toxicants can lower reproductive rates of organisms and affect rates of survival of juveniles to adulthood. Ability to avoid predators may be curtailed,... 

IV. Toxicity and Sublethal Effects of Selected Metal Ions. 144... 

At test termination, the concentration that kills 50% of the test organisms (LC50 value) is determined using probit analysis or graphical interpolation. Unlike in chronic toxicity tests, there is no test solution renewal, the organisms are unfed, and there is no analytical verification of the test concentrations. Furthermore, cumulative, chronic, and sublethal effects of a chemical usually are not evaluated in acute toxicity tests, although frequently behavioral changes and lesions caused by a chemical can be determined. 

Application factors are still used at the present time, although on a limited scale, particularly when enough knowledge is available regarding the sublethal effects of the toxic substances. For example, application factors of 0.01 and 0.05 have been established in Canada for persistent and non-persistent toxic substances, respectively (CCME, 1991). The potential health risks arising from using these application factors appear to be acceptable until clearer cause and effect dosages are available. 

McMahon and Bimbaum (1990) suggested that it is the disposition of CN within the brain that may be most important in assessing the acute toxicity of the compound (p. 313). The following discussion describes available information on the sublethal effects of CN on behavior and related parameters, as well as the behavioral effects of CN treatments and prophylactics. 

Sublethal effects of injected ricin have been documented in isolated case reports, and are difficult to distinguish from those of many other toxic or infectious agents. A 36 year old chemist who allegedly injected himself (i.m.) with an unknown amount of ricin prepared from homogenized castor seed, for example, complained of headache and rigors approximately 10 h later, then developed anorexia and nausea, a sinus tachycardia, erythematous areas around the puncture wounds, and local lymphadenopathy at the injection sites (Fine et al., 1992). 

Gallagher, E.P., R.C. Cattley, and R.T. di Giulio. 1992. The acute toxicity and sublethal effects of chlorothalonil in channel catfish (Ictalurus punctatus). Chemosphere 24 3-10. 

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