salicylates and Neural-Tube-Defects

Benzyl salicylate is used as a fragrance ingredient and an ultraviolet light absorber, but its toxicity is unknown. Therefore, toxicity tests and hazard classification were conducted for screening assessment under the Japanese Chemical Substances Control Law. Benzyl salicylate was found to be non-genotoxic in vitro based on the chromosomal aberration test using Chinese hamster lung cells. However, the combined repeated-dose and reproductive/developmental screening toxicity test, in which male and female rats were administered benzyl salicylate by gavage at 0, 30, 100, or 300 mg/kg/day for 42 and 41-46 days, respectively, from 14 days before mating until postnatal Day 4, showed that repeated doses had major effects on the thymus, liver, epididymis, and femur at 100 and/or 300 mg/kg/day. Furthermore, although benzyl salicylate had no effect on the estrus cycle, fertility, corpus lutea, or implantation rate, embryonic resorption, offspring mortality, and neural tube defects were observed at 300 mg/kg/day, and the offspring had lower body weights at 30 and 100 mg/kg/day, suggesting teratogenicity similar to other salicylates. Based on the developmental toxicity, this chemical was classified as hazard class 2, with a lowest observed adverse effect level (LOAEL) of 30 mg/kg/day and a D-value of 0.003 mg/kg/day.

Topics: Animals; Cell Line; Cricetulus; Dose-Response Relationship, Drug; Embryo Loss; Embryo, Mammalian; Female; Fibroblasts; Lung; Male; Mutagenicity Tests; Neural Tube Defects; Odorants; Rats, Sprague-Dawley; Reproduction; Salicylates; Toxicity Tests

Prescription data for the three months before the last menstrual period and for the first trimester of pregnancy were obtained for 764 mothers whose children had a defect of the central nervous system and for an equal number of mothers of control babies born from the same doctors' practices. There was a statistically significant difference overall between the numbers of mothers who were prescribed drugs in the study and control groups during the trimester before the last menstrual period but no such difference was found for the first pregnancy trimester, nor was there a significant difference for any specific group of drugs. For a composite group of non-steroid anti-inflammatory drugs, salicylates, and sulphasalazine there was a significant difference for the trimester before the last menstrual period. There are arguments against such an artificial grouping, however, and when the individual drugs were considered the comparisons were no longer significant. The odds ratios for all medicines containing folic acid taken in the trimester before the last menstrual period were considerably less than unity, in contrast with nearly all other comparisons. This supports a suggested protective effect against neural tube defects of folic acid supplements begun before the onset of pregnancy but the odds ratios of these comparisons were not statistically significant.

Topics: Abnormalities, Drug-Induced; Abnormalities, Multiple; Adolescent; Adult; Anti-Inflammatory Agents; Female; Folic Acid; Humans; Maternal Age; Middle Aged; Neural Tube Defects; Pregnancy; Pregnancy Trimester, First; Salicylates; Sulfasalazine

Methyl salicylate was administered topically to pregnant hamsters at 7d9h and the teratogenic results were compared with those obtained following oral treatment with the same compound. Both treatments produced the same defect in embryos recovered at day 9: failure of fusion of the neural tube, especially in the area of the developing brain. Analysis of serum salicylate levels following both treatments produced similar curves and indicated that teratogenic levels of salicylate can reach the maternal circulation after topical exposure.

Topics: Administration, Oral; Administration, Topical; Animals; Cricetinae; Female; Maternal-Fetal Exchange; Neural Tube Defects; Pregnancy; Salicylates