Diepoxybutane and mitomycin C toxicity is associated with the induction of oxidative DNA damage in sea urchin embryos

Diepoxybutane (DEB)- and mitomycin C (MMC)-associated toxicity was investigated in embryos from the sea urchin (SU) species Sphaerechinus granularis. DEB- and MMC-induced toxicity resulted in S. granularis embryos and larvae at concentrations ranging 10(-5) to 10(-4) M DEB, and 3 x 10(-6) to 3 x 10(-5) M MMC, in terms of larval malformations, developmental arrest and mortality. The formation of DNA oxidative damage, 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured in DEB- and in MMC-exposed embryos (at gastrula stage). A dose-dependent increase in 8-OHdG levels was observed that was significantly correlated with DEB- and MMC-induced developmental defects. The results lend further support to the body of evidence associating both DEB and MMC toxicity with oxidative stress, including DNA oxidative damage.