Toxic individual susceptibility

Experiments involving the use of dimethyl sulphate should be carried out by students only under immediate supervision. Not only is the vapour of dimethyl sulphate highly poisonousy but the cold liquid itself is absorbed easily through the skin, with toxic results individual susceptibility to ditnethyl sulphate poisoning varies and may be very high. If the sulphate is splashed on to the hands, wash immediately with plenty of concentrated ammonia solution in order to hydrolyse the methyl sulphate before it can be absorbed through the skin (see p. 528). 

No studies were located indicating that any populations are unusually susceptible to heptachlor or heptachlor epoxide. There is a possibility that very young children may exhibit particular susceptibility to hepatic effects because of the immaturity of the hepatic microsomal system. Heptachlor is bioactivated to produce heptachlor epoxide which is more toxic than heptachlor. Preadolescent children have a greater rate of glutathione turnover, and they are expected to be more susceptible to heptachlor epoxide-induced toxicity. Their susceptibility would probably depend upon their ability to detoxify heptachlor epoxide. Individuals who show reduced liver function for other... 

Thousands of substances are added to foods to enhance their marketability (appearance, taste, texture, etc.), storage properties, or nutritive value, any of which may cause toxicity in susceptible individuals (Table lA). Microbial or fungal contamination of food, either during processing or storage, can introduce potent toxins into food. 

DNA damage in children environmentally exposed to lead with assessment of individual susceptibility to toxic effect of lead, and genetic polymorphism of lead biotransformation and mechanism of DNA repair Study will assess role of lead exposure in cytogenetic damage in children (European Commission 2004). 

White Phosphorus. Studies have shown that pregnant rats are more susceptible than nonpregnant female and male rats to the lethal effects of white phosphorus during late gestation or parturition. It is not known if pregnant women would also represent an unusually susceptible population. Human exposure to white phosphorus has shown that the liver, kidney, and cardiovascular systems are some of the primary targets of toxicity. Individuals with pre-existing liver, kidney, heart, or circulatory disorders may be unusually susceptible to white phosphorus toxicity. 

Grandjean P (1992) Individual susceptibility to toxicity. Toxicol Lett, 64-65 43-51. 

Nebert DW (2005) Inter-individual susceptibility to environmental toxicants — A current assessment. Toxicol Appl Pharmacol, 207 S34-S42. 

Toxicity is the relative effects of a substance on living organisms. This is not important as an identifying feature, but should always be considered for all materials in collections. There may be toxic substances in the objects in a collection and in the treatments those objects have received. Toxins are often the products of deterioration of natural materials. A person s reaction to toxic substances varies according to individual susceptibility, body weight, age, physical condition, and previous exposure. 

Individual susceptibility is one of the most important variables in the development of chronic benzene toxicity. Aksoy et al. (1976) suggested familial susceptibility as one of the main factors in the frequency of chronic benzene toxicity. Two patients with pancytopenia associated with chronic exposure to benzene were cousins. One of these two patients died of aplastic anemia the son of this patient presented with leukopenia a short time after exposure to this chemical. Genetic polymorphism with regard to the P-450 enzymes that metabolize benzene to its reactive metabolites may render some individuals at higher risk to the toxic effects of benzene (Kato et al. 1995). Although there are possible indications of genetic... 

Hattis, D., P. Banati, and R. Goble 1999. Distributions of individual susceptibility among humans for toxic effects—For what fraction of which kinds of chemicals and effects does die traditional 10-fold factor provide how much protection Ann. N.Y. Acad. Sd. 895 286-316. 

In dealing with these chlorinated hydrocarbons, it must be remembered that a toxic acdon may result from repeated exposure to concentradons that are too low to produce a narcodc effect, and that, consequendy, are too low to give warning of danger. Individual susceptibility varies widely. Certain workmen may be seriously affected by concentrations that seem to have no effect on fellow employees at the same exposure. 

Morphine is the constituent of opium most responsible for its toxic effects. When taken orally, the effects of morphine poisoning begin to appear in 20-40 minutes if taken hypodermically, the symptoms appear much earlier and narcotism is more likely to follow the early symptoms. Abuse leads to habituation or addiction. Individual susceptibility varies greatly and children are more susceptible than adults. When heated to decomposition it emits toxic fumes of NOx. 

It is of interest tl at racial 4 iM eptiUitily to the toxic action of mustard gas exists aliiieti art> more susceptible than n roea. There is also an individual susceptibility tt> ihc toxic action of mustard gas. particularly of the skin, and also of the rrspiratory tr u r... 

Hundreds of patients have received huge doses of atropine and scopolamine (up to 250 mg), sometimes given three times a week for up to 4 mo, and this form of therapy continues in Eastern Europe today. A chronic behavioral syndrome of toxicity appears unlikely, and single or even multiple exposures to the anticholinergic drugs used In the volunteers, frequently at low doses, are deemed Insufficient to stimulate a persistent toxic syndrome. Of course. Individual susceptibility to acute effects, which may trigger a long-term effect, cannot be excluded. 

Epoxide hydrolase activity is present in most mammalian tissues and is high in the endoplasmic reticulum and cytosol of the liver. Humans appear to have considerable intersubject variability in the activity of epoxide hydrolase that may impact on individual susceptibility to the toxic action of certain epoxides This variability argues for the existence of several epoxide hydrolases. 

The use of co-trimoxazole in HIV-positive patients has been associated with a high rate of hypersensitivity reactions (40-80%), attributed to the bioactivation of the sulfonamide component, sulfamethoxazole, to its toxic hydroxylamine and nitroso metabolites. In a study of HIV-positive patients with (n = 56) and without n — 89) hypersensitivity to co-trimoxazole, functionally significant polymorphisms in the genes coding for enzymes involved in co-trimoxazole metabolism were unlikely to have been major predisposing factors in determining individual susceptibility to co-trimoxazole hypersensitivity (179). 

Methylmercury causes subtle to severe neurologic effects depending on dose and individual susceptibility. EPA considers methylmercury to have sufficient human and animal data to be classified as a developmental toxicant. Methylmercury accumulates in body tissue consequently, maternal exposure occurring prior to pregnancy can contribute to the overall maternal body burden and result in exposure to the developing fetus. In addition, infants may be exposed to methylmercury through breast milk. 

It has been proposed to use hemoglobin adducts in biomonitoring, as a dosimeter for the biologically active dose of arylamines/arylacetamides. This may also provide information about the individual susceptibility to the toxic and carcinogenic effects of these chemicals30,31. Field workers exposed to Propanil (38), a major herbicide in rice paddies,... 

Sharing importance with individual susceptibility is the previously mentioned concept of critical body burden of toxicant as a prerequisite for inducing renal cell injury. It is this concept of body burden that helps explain why the various clinical manifestations of toxin induced renal disease run the gamut from sudden deterioration of renal function to the insidious loss of function. 

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