Main drivers of mercury levels in Southern Ocean lantern fish Myctophidae.

Main drivers of mercury levels in Southern Ocean lantern fish Myctophidae. Environ Pollut. 2020 Sep;264:114711 Authors: Seco J, Xavier JC, Bustamante P, Coelho JP, Saunders RA, Ferreira N, Fielding S, Pardal MA, Stowasser G, Viana T, Tarling GA, Pereira E, Brierley AS Abstract Myctophids are the most abundant fish group in the Southern Ocean pelagic ecosystem and are an important link in the Antarctic marine food web. Due to their major ecological role, evaluating the level of mercury (Hg) contamination in myctophids is important as a step towards understanding the trophic pathway of this contaminant. The concentrations of total Hg were determined in muscle, gill, heart and liver tissue of 9 myctophid species to quantify tissue partitioning variability between species. Organic Hg concentration and proportion in muscle was also determined. Hg concentrations were higher in the liver and heart than in muscle and gills, but the proportion of organic Hg was almost 100% in muscle, indicating that the main uptake route for Hg is through the diet. Most of the species analysed have similar vertical and horizontal distributions, and similar feeding modes and prey. Geographical and temporal variability of Hg concentrations was examined using samples from 3 different sampling cruise (2007/08, 2015/16 and 2016/17) and 2 locations (South Georgia and South Orkneys Islands). Our results appear to indicate a decreasing trend in Hg contamination over ...
Source: Environmental Pollution - Category: Environmental Health Authors: Tags: Environ Pollut Source Type: research