Effects on Mammals

1 mg kg methylmercury resulted in a slight tendency for two out of five animals 

Mercury concentrations as high as -lOOmgkg liver and 130mgkg hair were detected in this animal. The panthers most at risk appear to be those which consume mercury-contaminated raccoons, which in turn consume mercury-contaminated aquatic life, including invertebrates, fish and amphibians. In addition to mortality, adverse effects of mercury on the reproductive success of this endangered animal are most likely (Roelke et al. 1993). 

Many vertebrate species possess the capability to detoxify and sequester mercury. The extent to which this is developed appears to be related to the animal s feeding habit, and 

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Bates, Hewlett, and Lloyd (I) found that both piperonyl butoxide and SKF 525A, the ester of 2-diethylaminoethyl 2,2-diphenyl-w-pentanoate, synergized the action of pyrethrins on insects of species of the lesser mealworm beetles and houseflies but both antagonized the action of malathion. SKF 525A is known to increase the effects on mammals of drugs of various types and has been shown to synergize pyrethrins. 

Some organochlorine, organophosphorus, and carbamate insecticides used after World War II (since 1945) were found to have various problems of adverse effects on mammals and environmental behavior and influences. The use of many industrial chemicals has been prohibited because those contained as impurities in minute quantities produced critical toxic substances by transformation and repeated chemical reactions in their environment. 

Biomagnification, which is the phenomenon that a chemical accumulates in species through different trophic levels in a food web, may cause toxic effects on mammals and birds as a secondary poisoning. Next to direct effects on soil organisms (see above), these indirect effects cam be considered in deriving critical limits for soil, by the use of simple food web models. 

A variety of methods are available to test a chemical for mutagenicity, i.e., its effect on the genetic material. The Ames Test has gained most recognition as a shortterm test [23],This is a bacterial test which allows fast performance and requires limited expense. Its correlation with the mutagenicity of mammals or even with a carcinogenic effect on mammals or humans has repeatedly been tested [24], but remains controversial. 

Hodgson E, Philpot RM, Interaction of methylenedioxyphenyl (1,3-benzodioxole) compounds with enzymes and their effect on mammals. Drug Metab RevI>a i - iQ, 1974. 

Insects and mites are animals and, traditionally, the most effective compounds for their control have been compounds that interfere with nerve function. Fundamentally, all animals have the same mechanisms for detecting and transmitting nerve impulses. Nerve-active compounds that kill insects will usually have some effects on mammals. 

Many coumarins are found in plants and a comprehensive review is available (78FOR(35)i99). Coumarin has a pleasant taste and odour and was used for flavouring until its toxic action on the liver was discovered. Among other coumarins which have toxic effects on mammals are a group called aflatoxins, e.g. aflatoxin Gi, (221), which are secondary metabolites of fungi of the Aspergillus genus. Some of these compounds have been present in animal feeds and caused deaths of the animals. In contrast, other coumarin derivatives,... 

The bacterium Bacillus thuringiensis forms an internal crystal that contains a number of insecticidal protein toxins. When eaten by the insect, the crystal dissolves in the midgut, the toxin mixture is released, and the proteins are cleaved into active forms. The toxins bind specifically to midgut cells and assemble a pore that leads to disintegration of the cells, gut paralysis, and death. B. thuringiensis strains have toxins specific for caterpillars, beetles, or flies. They have little or no effect on mammals. 

The acute dermal irritation is the study of reversible inflammatory changes in the skin of test animals following the application of a test chemical. Acute dermal corrosion is the study of irreversible tissue damages in the skin following the application of a test chemical. In the evaluation of toxic characteristics of a chemical, determination of the irritant or corrosive effects on mammal skin is an important study step. Information derived from this test indicates the existence of hazards likely to arise from skin exposure to the test chemical. 

Hodgson, E., and Philpot, R. M. Interaction of methylenedioxyphenyl (1,3-benzodioxole) compounds with enzymes and their effects on mammals. Drug Metab. Rev. 3, 231,1974. Hodgson, E. Induction and inhibition of pesticide-metabolizing enzymes Roles in synergism of pesticides and pesticide action. Toxicol. Ind. Health 15, 6,1999. 

Because of its good taste and favorable physiological effects on mammals, theanine could be a new food additive, and several investigations on its effective production have been performed. 

At the same time this method of insect sterilisation involves the hazard of various toxic side-effects, as interference in DNA synthesis may lead to teratogenic, mutagenic and carcinogenic effects or sterilising effects on mammals (Klassen and Chang, 1966 Hayes, 1964 Palmquist and La Chance, 1966 Barnes, 1964). 

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