Four-Week Repeated Skin Contact Study with Glutaraldehyde in Rats

Abstract Glutaraldehyde (GA: CAS Number 111-30-8) is a widely used industrial chemical and biocide from which skin contact may occur. The potential for local and systemic toxicity by repeated skin contact was investigated in Fischer 344 rats using occluded epicutaneous applications of 2.5, 5.0, and 7.5% aqueous GA solutions at a dose volume of 2.0 ml/kg/day, 6 h/day, for 20 applications over a 26 day period. This was equivalent to 50, 100, and 150 mg GA/kg/day. Controls received filtered water at 2.0 ml/kg/day. There were no treatment-related mortalities or clinical signs of systemic toxicity. Local skin irritation, mainly erythema and edema, was minimal and present only intermittently during the treatment period, and resolved in 4-week recovery animals. There were slight decreases in body weight, body weight gain, and food consumption. A gender-related discrepancy in water consumption, apparently increased in males and decreased in females, was probably related to proximity to the animal holding room air supply, with animals closest to the air intake having the greatest water consumption. Increases in platelet count, urea nitrogen, and adrenal gland weight, which generally resolved during a 4-week recovery period, were similar to the responses seen in other studies involving the recurrent epicutaneous application of irritant materials of various chemical classes to the rat. Histopathological findings were restricted to areas of GA-treated skin: acanthosis, dermatitis, hyperkeratosis, parakeratosis, epidermitis, and dermal fibrosis. Thus, in vivo short-term recurrent application of GA solutions, up to 7.5%, to rat skin produced minimal skin irritation but no evidence of systemic toxicity.