Biomarkers of petroleum contamination in the digestive gland of Perna viridis (L.)

Oxidative stress responses were evaluated in the digestive gland tissue of Perna viridis exposed to water-accommodated fractions (WAFs) of petrol and diesel at 0.5% and 5% concentrations over 5-, 10-, and 15-day periods. Increased lipid peroxidation, protein carbonyl, DNA integrity, and hydrogen peroxide in WAF-exposed specimens are indicative of oxidative damage due to dissolved petroleum extracts. A consistent increase in superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, reduced glutathione, and ascorbic acid in WAF-exposed specimens signify the importance of antioxidants in protecting the cell against the oxidative damage arising from petroleum contamination. The responses of field specimens collected from petroleum-contaminated sites support the observed laboratory experimental results. This research recommends the use of these oxidative stress indices in the digestive gland tissue of Perna viridis as biomarkers of petroleum contamination.