Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)


Ocean, Coastal, and Earth Sciences

First Advisor

Dr. MD Saydur Rahman

Second Advisor

Dr. Abdullah Faiz Rahman

Third Advisor

Dr. Amit Raysoni


Environmental pollution increases due to anthropogenic activities. Different types of pollutants and/or chemicals impair growth, reproduction and development in aquatic organisms. Tributyltin (TBT, an organotin compound) is a tremendously toxic substance which widely uses as antifouling paints used in boats, hulls, and ships. The toxic effect of TBT is well documented in teleost species. The American oyster (Crassostrea virginica) is an ideal shellfish species to study on TBT exposure DNA lesion and oxidative/nitrative stress. In this study, the effects of TBT on 8’-hyrodxy-2’-deoxyguanosine (8-OHdG, a molecular marker), dsDNA, dinitrophenyl protein (DNP, a biomarker of reactive oxygen species, ROS), 3-nitrotyrosine protein (NTP, an indicator of reactive nitrogen species, RNS), catalase (CAT, an antioxidant) in gills and digestive glands of oysters. We also analyzed extrapallial fluid (EPF) conditions in oysters. Immunohistohemical results showed that TBT exposure significantly increased 8-OHdG, dsDNA, DNP and NTP expressions in gills and digestive glands of oysters compare to control. However, EPF pH and protein concentration were decreased in TBT exposure oysters. Collectively, these results suggest that antifouling biocides-driven ROS/RNS induces DNA damage which may lead to decreased various physiological functions in oysters.


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