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Increased human susceptibility to organophosphates?
302
Information Section
Alcohol and hormone replacement therapy In a Boston study of 24 post-menopausal women, half of whom received oral hormone replacement therapy (HRT) in the form of oestradiol and a progesterone derivative, moderate alcohol consumption (0.7 g/kg body weight) was found to produce %ignificant and sustained elevations in circulating [o]estradiol to levels 300% higher than those targeted" in clinical use of HRT. There was no significant increase in plasma oestradiol levels in the non-HRT women. The investigators considered the need for further evaluation of the "potential health risks and benefits of the interactions" between acute alcohol ingestion and I-IRT (Ginsburg et aL, Journal of the American Medical Association 1996, 276, 1747).
Indole-3-carbinol and male rat offspring Indole-3-carbinol, a natural component of cruciferous vegetables, caused reproductive abnormalities in the male offspring of rats given an oral dose of 1 or 100 mg/kg body weight on day 15 of pregnancy. Although 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (given at 1.0 or 2.0 ~g/kg body weight) produced a wider range of reproductive effects, there were some common features in the toxicity of the carbinol and dioxin. The investigators concluded that "human health risk assessment of TCDD and related compounds based on laboratory animal experiments should consider the effects of [indole-3-carbinol and other biologically related materials].., which can be present at relatively high levels in cooked foods for humans" (Wilker et aL, Toxicology and Alyplied Pharmacology 1996, 141, 68).
biochemical markers of smoke exposure were assessed in 161 smokers, 76 of whom smoked mentholated cigarettes. After adjustment for race, cigarettes smoked/day and mean amount of each cigarette smoked, menthol was found to be associated with higher serum cotinine levels and higher levels of carbon monoxide in expired air (Clarke et al., Chest 1996, 110, 1194).
Methacrylonitrile and developmental toxicity in rats and rabbits In NTP studies conducted to ~further characterize the maternal and developmental toxicity of [methacrylonitrile]', a component of mainstream smoke from unfiltered cigarettes, rats and rabbits were treated (by stomach tube) on days 6-15 and 6-19 of pregnancy, respectively. There were no adverse developmental effects at 50 (rats) and 5 mg/kg body weight/day (rabbits), the top doses tested. Maternal effects (increased relative liver weight) were seen in the rats at 25, but not at 5 mg/kg body weight/day (George et aL, FundamentalandApplied Toxicology 1996, 34, 249).
Increased human susceptibility to organophosphates? Organophosphates are well-known toxicants affecting the nervous system through the inhibition of acetylcholinesterase. A recent tissue culture study identified marked interspecies differences in the enzymatic handling of paraoxon, a representation organophosphate. The results suggest that humans may be less adept than rodents at detoxification (Kaliste-Korhonen et aL, Human and Experimental Toxicology 1996, 15, 972).
Genotoxicity of diuron Smoking reduces depression 16 experienced and heavy smokers had lower levels of monoamine oxidase A (MAO) in the brain than did 15 non-smokers. MAO inhibitors are known to exhibit antidepressant activity. The reduction in MAO level was half that detected in four of the non-smoking group treated with a low dose of an antidepressant MAO inhibitor drug for 3 days (Fowler et aL, Proceedings of the National Acaderny of Sciences of the U.S.A. 1996, 93, 14065).
Greater risk from mentholated cigarettes? The use of mentholated cigarettes may be associated with increased health risks from smoking, US researchers have concluded. Smoking habits and
Diuron, a substituted urea herbicide, has been found to induce chromosome damage (micronuclei) in bone marrow cells from mice treated with single intraperitoneal injections of 340 or 170 mg/kg body weight. No convincing evidence of activity was seen at 85 mg/kg body weight (Agrawal et al., Toxicology Letters 1996, 89, 1).
Aluminum phosphide acute toxicity in humans A study of the 195 patients admitted to an Indian hospital over a 5-yr period following ingestion of aluminium phosphide, a fumigant used to protect grain from pests and rodents, has reported mortality at doses as low as 1.5 g. Among the 115 patients who died, there was congestion of a wide
Information Section
Alcohol and hormone replacement therapy In a Boston study of 24 post-menopausal women, half of whom received oral hormone replacement therapy (HRT) in the form of oestradiol and a progesterone derivative, moderate alcohol consumption (0.7 g/kg body weight) was found to produce %ignificant and sustained elevations in circulating [o]estradiol to levels 300% higher than those targeted" in clinical use of HRT. There was no significant increase in plasma oestradiol levels in the non-HRT women. The investigators considered the need for further evaluation of the "potential health risks and benefits of the interactions" between acute alcohol ingestion and I-IRT (Ginsburg et aL, Journal of the American Medical Association 1996, 276, 1747).
Indole-3-carbinol and male rat offspring Indole-3-carbinol, a natural component of cruciferous vegetables, caused reproductive abnormalities in the male offspring of rats given an oral dose of 1 or 100 mg/kg body weight on day 15 of pregnancy. Although 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (given at 1.0 or 2.0 ~g/kg body weight) produced a wider range of reproductive effects, there were some common features in the toxicity of the carbinol and dioxin. The investigators concluded that "human health risk assessment of TCDD and related compounds based on laboratory animal experiments should consider the effects of [indole-3-carbinol and other biologically related materials].., which can be present at relatively high levels in cooked foods for humans" (Wilker et aL, Toxicology and Alyplied Pharmacology 1996, 141, 68).
biochemical markers of smoke exposure were assessed in 161 smokers, 76 of whom smoked mentholated cigarettes. After adjustment for race, cigarettes smoked/day and mean amount of each cigarette smoked, menthol was found to be associated with higher serum cotinine levels and higher levels of carbon monoxide in expired air (Clarke et al., Chest 1996, 110, 1194).
Methacrylonitrile and developmental toxicity in rats and rabbits In NTP studies conducted to ~further characterize the maternal and developmental toxicity of [methacrylonitrile]', a component of mainstream smoke from unfiltered cigarettes, rats and rabbits were treated (by stomach tube) on days 6-15 and 6-19 of pregnancy, respectively. There were no adverse developmental effects at 50 (rats) and 5 mg/kg body weight/day (rabbits), the top doses tested. Maternal effects (increased relative liver weight) were seen in the rats at 25, but not at 5 mg/kg body weight/day (George et aL, FundamentalandApplied Toxicology 1996, 34, 249).
Increased human susceptibility to organophosphates? Organophosphates are well-known toxicants affecting the nervous system through the inhibition of acetylcholinesterase. A recent tissue culture study identified marked interspecies differences in the enzymatic handling of paraoxon, a representation organophosphate. The results suggest that humans may be less adept than rodents at detoxification (Kaliste-Korhonen et aL, Human and Experimental Toxicology 1996, 15, 972).
Genotoxicity of diuron Smoking reduces depression 16 experienced and heavy smokers had lower levels of monoamine oxidase A (MAO) in the brain than did 15 non-smokers. MAO inhibitors are known to exhibit antidepressant activity. The reduction in MAO level was half that detected in four of the non-smoking group treated with a low dose of an antidepressant MAO inhibitor drug for 3 days (Fowler et aL, Proceedings of the National Acaderny of Sciences of the U.S.A. 1996, 93, 14065).
Greater risk from mentholated cigarettes? The use of mentholated cigarettes may be associated with increased health risks from smoking, US researchers have concluded. Smoking habits and
Diuron, a substituted urea herbicide, has been found to induce chromosome damage (micronuclei) in bone marrow cells from mice treated with single intraperitoneal injections of 340 or 170 mg/kg body weight. No convincing evidence of activity was seen at 85 mg/kg body weight (Agrawal et al., Toxicology Letters 1996, 89, 1).
Aluminum phosphide acute toxicity in humans A study of the 195 patients admitted to an Indian hospital over a 5-yr period following ingestion of aluminium phosphide, a fumigant used to protect grain from pests and rodents, has reported mortality at doses as low as 1.5 g. Among the 115 patients who died, there was congestion of a wide