LE3 .A278 2022

2022

O'Driscoll, Nelson

Acadia University

Bachelor of Science

Honours

Earth and Environmental Science

Earth & Environmental Sciences

This project investigated mercury contamination in coastal mussels at the Minas Basin, Bay of Fundy. This research aims to evaluate whether mussels are a valid and reliable biomarker of coastal mercury pollution. There was low contamination at the sampling sites (mean sediment total mercury = 5.1 ng/g dry weight (d.w.)). The mean concentration of total mercury in the mussel tissues was 62.3 ng/g d.w. (SD = 13.7 ng/g d.w.; n = 57). Through a regression analysis, we determined that total mercury and methylmercury in tissues were significantly negatively related with the mussel’s condition index (p < 0.001, R = -0.5, R2 = 0.24 in both cases). Additionally, we found a negative and significant linear relationship between the logarithm of the whole organism soft tissue mass (d.w.) and the logarithm of the total mercury content (p < 0.001; R2 = 0.23) Through a Pearson correlation, shell length was found to have a negative correlation with the total mercury in soft tissue samples (p value = 0.01, R = -0.3). The mean concentration of methylmercury in soft tissues was 13.2 ng/g d.w. (SD = 6.3 ng/g d.w.), equivalent to 1.7 ng/g wet weight (w.w.). This is lower than Environment Canada’s tissue residue guideline for effects on aquatic organisms for methylmercury (33 ng/g w.w.) In the mussel shells, total mercury in all samples was below the method detection limit (MDL = 1.7 ng/g d.w.). As such, for this study, the shells could not be used as a bioindicator of soft tissue concentration of mercury.

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https://scholar.acadiau.ca/islandora/object/theses:3869