Abstract

Mercury (Hg) uptake in fish is affected by diet, growth, and environmental factors such as primary productivity or oxygen regimes. Traditionally, fish Hg exposure is assessed using muscle tissue or whole fish, reflecting both loss and uptake processes that result in Hg bioaccumulation over entire lifetimes. Tracking changes in Hg exposure of an individual fish chronologically throughout its lifetime can provide novel insights into the processes that affect Hg bioaccumulation. Here we use eye lenses to determine Hg uptake at an annual scale for individual fish. We assess the widely distributed benthic round goby (Neogobius melanostomus) from the Baltic Sea, Lake Erie, and the St. Lawrence River. We aged layers of the eye lens using proportional relationships between otolith length at age and eye lens radius for each individual fish. Mercury concentrations were quantified using laser ablation inductively coupled plasma mass spectrometry. The eye lens Hg content revealed that Hg exposure increased with age in Lake Erie and the Baltic Sea but decreased with age in the St. Lawrence River, a trend not detected using muscle tissues. This novel methodology for measuring Hg concentration over time with eye lens chronology holds promise for quantifying how global change processes like increasing hypoxia affect the exposure of fish to Hg.

Keywords

otoliths; round goby; diet; Lake Erie; St. Lawrence River; Baltic Sea; hypoxia

Published in

Environmental Science and Technology Letters
2023, Volume: 10, number: 3, pages: 222-227
Publisher: AMER CHEMICAL SOC

SLU Authors

• Limburg, Karin

  • Department of Aquatic Resources (SLU Aqua), Swedish University of Agricultural Sciences
    
  • State University of New York (SUNY) College of Environmental Science and Forestry

UKÄ Subject classification

Fish and Aquacultural Science
Environmental Sciences


Publication identifier

DOI: https://doi.org/10.1021/acs.estlett.2c00755

Permanent link to this page (URI)

https://res.slu.se/id/publ/120564