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Methyl eugenol is a naturally occurring material found in a variety of food sources, including spices, oils, and nutritionally important foods such as bananas and oranges. Given its natural occurrence, [...]

The effect of various metal compounds on the DNA of Chinese hamster ovary (CHO) cells was studied. Both NiCl and crystalline NiS caused DNA strand breaks in cultured CHO cells, whereas amorphous NiS did not. Strand breaks were quantitated by determining the number average molecular weight of DNA following treatment with the metal compounds. Exposure of cells to crystalline NiS, CoS, CdS, AgS, CuS and NiS at 10 μg/ml for 24 h also induced DNA strand breaks. Similar exposure to activated charcoal, which was also actively phagocytosed, failed to cause any effect on the DNA of CHO cells. In the case of NiCl and NiS the effect was shown to be both time and dose dependent. Other soluble metal compounds such as HgCl, CaCrO, and CdCl also decreased the molecular weight of DNA while MnCl, ZnCl and FeCl caused no significantly detectable change in DNA molecular weight. These effects, which occur at low metal concentrations suggest that nickel and other metals which cause cellular transformation have a very selective and specific effect upon DNA. [ABSTRACT FROM PUBLISHER]

Use of 2-ethylhexyl-2-cyano-3,3-diphenyl acrylate (Octocrylene) in commercial sunscreen products has increased considerably in recent years. To support larger scale human exposure to this compound, additional toxicological information was needed in several key areas. The present studies evaluated subchronic toxicity, developmental toxicity, and genotoxic potential of Octocrylene. In the subchronic study, male and female New Zealand white (NZW) rabbits treated topically with concentrations of octocrylene up to 534 mg/kg/day for 13 weeks showed slight to moderate dose-dependent skin irritation that correlated positively with a mild depression in body weight gain. Lack of associated histopathologic or clinical hematology abnormalities suggested that the body weight effect probably reflected a nonspecific response to topical irritation. In percutaneous developmental toxicity studies, NZW does were treated topically with Octocrylene at levels up to 267 mg/kg/day on Days 6 through 18 of gestation. Body weight gain, food consumption, and all maternal, reproductive, and offspring parameters evaluated were comparable between Octocrylene-treated and control animals. In the oral developmental toxicity assay, female CD-1 mice received oral doses of Octocrylene up to 1000 mg/kg/day on Days 8–12 of gestation. No evidence of maternal or developmental toxicity was seen at any dose tested. Genotoxicity was evaluated using the Chinese hamster ovary cell assay to assess clastogenicity and the mouse lymphoma cell assay to assess forward gene mutations. Octocrylene did not induce any significant increase in genotoxicity. This evaluation of toxicological potential supports the use of Octocrylene as a human photoprotectant. [ABSTRACT FROM PUBLISHER]

There are many reasons to study somatic cell gene mutation arising in vivo in humans. Mutations in critical genes almost certainly underlie pathological processes such as malignant transformations as well as some aspects of normal in vivo cell differentiation. Furthermore, in vivo somatic mutations of indicator genes provide realistic markers for genetic toxicology in that mutagen metabolism and delivery to genetic targets are automatically assessed, and individual differences in mutagen susceptibility may be determined.