Effect teratogenic

At the present time there are no rapid lower tier , i.e., nonmammalian screening systems which have been validated as capable of detecting teratogenic substances. The basic problem is that an applicable screening test must differentially detect substances to which the conceptus is uniquely susceptible . Virtually any toxic substance is capable of affecting the fetus at doses that are close to those which are toxic to the adult, but such coeffective teratogens would not necessarily pose a developmental hazard. 

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Tellurium is not an essential element, and teUurium compounds are in general more toxic than their selenium counterparts. MetaUic teUurium is known to have a teratogenic effect in rats, though no studies have been done on the toxicity of teUurium donor compounds (35). 

Many studies have reported a link between consumption of sunburned potatoes, ie, those exposed to the sun and having an accumulation of chlorophyll and solanine under the skin, with incidences of teratogenic effects and even death (59—61). Because sunburned potatoes in the commercial marketplace are relatively rare, and because the long-term effects of consumption of potatoes at the maximum estabUshed limits of solanine concentration are uncertain, there is equal uncertainty of the tme incidence of human toxicity (62). 

Teratogenic effects have been noted with 2- and 4-aminophenol in the hamster, but 3-aminophenol was without effect in the hamster and rat (129,130). 4-Aminophenol is known to inhibit DNA synthesis and alter DNA stmcture in human lymphoblasts (131,132) and is mutagenic in mouse micronuclei tests (133). The aminophenols have been shown to be genotoxic, as evidenced by the induction of sister chromatid exchanges (134,135), but they also exert a protective effect against DNA interaction with other noxious chemicals (136). After assessment of available data a recent report stated that the aminophenols were safe as cosmetic ingredients in their present uses and concentrations (137). 

No teratogenic effects were observed in mice and rats exposed to vapor concentrations of 300 ppm. Exposure levels having no effect on the mother are not anticipated to affect the fetus (36). 

Reproductive Toxicity. No data are available that impHcate either hexavalent or trivalent chromium compounds as reproductive toxins, unless exposure is by way of injection. The observed teratogenic effects of sodium dichromate(VI), chromic acid, and chromium (HI) chloride, adininistered by injection, as measured by dose-response relationships are close to the amount that would be lethal to the embryo, a common trait of many compounds (111). Reported teratogenic studies on hamsters (117,118), the mouse (119—121), and rabbits (122) have shown increased incidence of cleft palate, no effect, and testicular degeneration, respectively. Although the exposures for these experiments were provided by injections, in the final study (122) oral, inhalation, and dermal routes were also tried, and no testicular degeneration was found by these paths. 

Late Toxicity - Where there is evidence that a chemical can cause cancer, mutagenic effects, teratogenic effects, or delayed injury to vital organs such as the liver or kidney, a qualitative description of the chemical is given. The term implies long-term or chronic effects due to exposure to the chemical. 

The glutarimide best known to the lay public, thalidomide (40), owes its reputation not to efficacy, but to the wholly unanticipated and tragic teratogenic effects elicited by this compound. It might be noted that the very efficacy and lack of the usual barbiturate side effects shown by this drug led to its prescription as a hypnotic for expectant mothers. Condensation of the phthalimide of glutamic acid (39) with ammonia at elevated... 

One enantiomer of penicillamine (D-) exhibits antiarthritic properties but foe other is highly toxic (Figure 8.3). The teratogenic effects of thalidomide were induced by one enantiomer, foe other exhibited foe beneficial effects against morning sickness. 

Albendazole is contraindicated in patients with known hypersensitivity to the drug and during pregnancy (Category C). The drug has exhibited embiyotoxic and teratogenic effects in experimental animals. Albendazole is used cautiously in patients witii hepatic impairment and during lactation. The effects of albendazole are increased with dexamethasone and cimetidina... 

Chondroitin Chondroitin sulfate, chondroitin sulfuric acid, chonsurid Arthritis None significant if used as directed Because chondroitin is concentrated in cartilage, theoretically it produces no toxic or teratogenic effects. 

Studies on the reproductive function (three generations) and intrauterine development of rat showed no impairment of the rate of fertility and no sign of any teratogenic effect. The Ames test on mutagenicity was negative [101]. 

A study on Wistar rats by Farr et al. (2001) showed no maternal toxicity at doses up to 5 mg/kg body weight for dibutyltin dichloride signs of maternal toxicity — reduced body weight gain, decreased food consumption, and thymus weight — were observed at 10 mg/kg body weight. No teratogenic effects were seen at 10 mg/kg... 

The teratogenic effects of various dibutyltins with different anions have been studied by Noda et al. 

Nodal, Morita S, Baba A (1993) Teratogenic effects of various di-n-butyltins with different anions and butyl(3-hydroxybutyl)tin dilaurate in rats. Toxioology, 85 149-160. 

Kumar KBS, Devi KS. 1992. Teratogenic effects of methyl parathion in developing chick embryos. Vet Flum Toxicol 34 408-410. 

The detection of a potent dioxin impurity in a major herbicide has focused attention on the nature of chlorinated impurities in pesticides, and in a larger sense, impurities in all chlorinated industrial compounds used extensively in man s environment. The present 2,4,5-T controversy is overshadowed by the dioxin problem. Major disagreement still exists on their relative contributions to the teratogenic effects observed in chicks and the validity of interpretation of high dosage rates used to achieve these effects. We have avoided any assessment of the health-related aspects of dioxins but have dealt almost exclusively with dioxins as an environmental entity. 

Nonpharmacologic therapy such as dietary, physical, and behavioral approaches should be considered first. Pyridoxine (vitamin B6) 10 to 25 mg three to four times daily alone or in combination with an antihistamine such as doxylamine is often used for NVP.9,11,12 This combination was previously marketed as Bendectin or Debendox but was withdrawn due to concerns over possible teratogenic effects, although the literature did not support this claim.11,12 Pyridoxine is well tolerated, but doxylamine and other antihistamines commonly cause drowsiness. For more severe NVP, promethazine, meto-clopramide, and trimethobenzamide may be effective and have not been associated with teratogenic effects.9... 

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