DETECTION OF STYRENE AND STYRENE OXIDE-INDUCED DNA-DAMAGE IN VARIOUS ORGANS OF MICE USING THE COMET ASSAY

Styrene(100-500 mg/kg b.wt.) and styrene oxide (50-200 mg/kg b.wt.) we re given as a single intraperitoneal injection to female mice (C57BL/6 ) at various time intervals before sacrifice. Primary DNA damage in va rious organs was studied using alkaline single cell gel electrophoresi s (comet) assay. Both substances induced significant DNA damage in lym phocytes, liver, bone marrow and kidney after 4 hr. The lymphocytes an d liver cells were found to be the most sensitive cells to the DNA dam aging effects of both agents. With the exception of bone marrow cells, the degree of DNA damage in all other cell types was decreased from 4 hr to 16 hr after the administration of both compounds. A strong subl inear dose-response relationship was observed in the lymphocytes, live r and bone marrow cells, possibly indicating a saturation of the detox ifying enzyme systems in these organs. The present work suggests that the comet assay can be used for detection of primary DNA damage induce d by styrene and styrene oxide in vivo and for comparing the sensitivi ty of various target organs.