INTERACTIONS OF RADIOFREQUENCY RADIATION ON 2-METHOXYETHANOL TERATOGENICITY IN RATS

Concurrent exposures to chemical and physical agents occur in the work place; exposed workers include those involved with the microelectronic s industry, plastic sealers and electrosurgical units. Previous animal research indicates that hyperthermia induced by an elevation in ambie nt temperature can potentiate the toxicity and teratogenicity of some chemical agents. We previously demonstrated that combined exposure to radiofrequency (r.f.; 10 MHz) radiation, which also induces hypertherm ia and is teratogenic to exposed animals, and the industrial solvent 2 -methoxyethanol (2ME) produces enhanced teratogenicity in rats. A subs equent study replicated and extended that research by investigating th e interactive dose-related teratogenicity of r.f. radiation (sham expo sure or maintaining colonic temperatures at 42.0 degrees C for 0, 10, 20 or 30 min by r.f. radiation absorption) and 2ME (0, 75, 100, 125 or 150 mg/kg) on gestation days 9 or 13 of rats. The purpose of the pres ent research is to determine the effects of r.f. radiation (sufficient to maintain colonic temperatures at 42.0 degrees C for 10 min) on a r ange of doses of 2ME (0, 20, 40, 60, 80, 100, 120 and 140 mg kg(-1)) a dministered on gestation day 13 of rats. Focusing on characterizing th e dose-response pattern of interactions, this research seeks to determ ine the lowest interactive effect level. Day 20 fetuses were examined for external and skeletal malformations. The results are consistent wi th previous observations. Dose-related developmental toxicity was obse rved for 2ME both in the presence and absence of r.f. radiation. Howev er, concurrent RF radiation exposure changed the shape of the dose-eff ect curve of 2ME. These data indicate that combined exposure effects s hould be considered when developing exposure guidelines and interventi on strategies. (C) 1996 by John Wiley & Sons, Ltd.