Documents teratogenicity tests 28 results

Beryllium is a steel-grey, brittle metal, existing naturally only as the 9Be isotope. Its compounds are divalent. Beryllium has several unique properties. It is the lightest of all solid and chemically-stable substances, with an unusually high melting point, specific heat, heat of fusion, and strength-to-weight ratio. It has excellent electrical and thermal conductivities. Because of its low atomic number, beryllium is very permeable to X-rays. Its nuclear properties include the breaking, scattering, and reflecting of neutrons, as well as the emission of neutrons on alpha-bombardment.

"Evaluates the risks to human health and the environment posed by 1,3-dichloropropene, 1,2-dichloropropane and mixtures of these chemicals. Since the two compounds and mixtures have been widely used in agriculture as pre-plant fumigants applied by soil injection, the report gives particular attention to studies investigating behaviour in soil, risks of leaching and groundwater contamination, uptake by food crops, residues detected in drinking-water and food, and risks to agricultural workers and the general population. Over 300 studies, including proprietary toxicological data from the manufacturers, were critically assessed.
The report concludes that, when used at the recommended rate, 1,3-dichloropropene is unlikely to attain levels of environmental significance. Risks to the general population were judged negligible. Concerning occupational hazards, the report cites evidence, largely from case reports of poisoning, underscoring the need to follow appropriate safety precautions.
The report concludes that 1,2-dichloropropane poses a negligible risk to the general population. When used at the recommended rate, the compound is unlikely to attain levels of environmental significance. For workers, the compound is judged unlikely to pose a hazard, provided good work practices, hygienic measures, and safety precautions are followed.
Data on mixtures of dichloropropenes and dichloropropane are evaluated in the final monograph. This technical mixture previously enjoyed wide use as a soil nematocide before planting. Citing evidence of a significant potential for 1,2-dichloropropane derived from this mixture to leach from soil and contaminate well water and groundwater, the report recommends that mixtures of dichloropropenes and dichloropropane should not be used as a soil fumigant. "

"Evaluates the risks to human health and the environment posed by benomyl, a fungicide registered for use in 50 countries on over 70 crops, including cereals, cotton, soybeans, tobacco, mushrooms, grapes, bananas and other fruits. One of the most widely used members of the benzimidazole family of fungicides, benomyl is effective, at low usage rates, against more than 190 different fungal diseases. Because benomyl is rapidly converted to carbendazim in the environment and is extensively metabolized to carbendazim by experimental animals, data from studies of carbendazim, which is a fungicide in its own right, are also considered when evaluating the hazards of benomyl.
Concerning hazards to environmental organisms, the report cites data from laboratory and field studies indicating that benomyl, applied at recommended rates, has little effect on soil microbial activity, but some adverse effects on groups of fungi. Benomyl is toxic to earthworms in laboratory experiments at realistic exposure concentrations and as a result of recommended usage in the field; earthworm populations may take more than two years to recover. Although high toxicity to aquatic organisms has been demonstrated in laboratory tests, the report concludes that this effect is unlikely to be seen in the field, due to the low bioavailability of sediment-bound residues.
For the general population, the main source of potential exposure is noted to be through the ingestion of food crops containing residues of benomyl and carbendazim. Though benomyl has been shown to cause contact dermatitis and dermal sensitization in some farm workers, the report found no evidence that either of these compounds can cause systemic toxic effects in occupationally exposed subjects or the general population. The report cites findings from animal studies suggesting that both compounds pose a very low risk for acute poisoning in humans."

"At a time when more corporate employers are using genetic information as a cornerstone of their hiring practices, when workers find their chromosomes considered alongside their resumes, the ramifications of genetic testing demand further examination. Risky Business analyzes health screening in the workplace--three major types of testing are examined: genetic screening in which job applicants and employees are tested for inherited traits that may predispose them to the disease:genetic monitoring that aims to detect genetic damage among current employees that could indicate exposure to dangerous chemicals; and teratogenic risk in which laboratory cultures and animals are used to provide evidence of the effects of chemical exposure on humans. "

Tributyltin (TBT) compounds are organic derivatives of tetravalent tin. They are characterized by the presence of covalent bonds between carbon atoms and a tin atom and have the general formula (n-C4H9)3Sn-X (where X isan anion). The purity of commercial tributyltin oxide (TBTO) is generally above 96%; the principal impurities are dibutyltin derivatives and, to a lesser extent, tetrabutyltin and other trialkyltin compounds. TBTO is a colourless liquid with a characteristic odour and a relative density of 1.17 to 1.18.