Effect of Land Cover on Ecoregion‐Scale Spatial Patterns of Mercury Contamination of Largemouth Bass in the Southeastern United States

Consumption of methylmercury (MeHg)‐contaminated fish is the primary source of MeHg in humans and poses a hazard to human health. Because of widespread atmospheric deposition of inorganic mercury (IHg), all water bodies in the United States have been contaminated with Hg. In aquatic ecosystems, IHg...

Full description

Saved in:
Bibliographic Details
Published in:Environmental toxicology and chemistry 2022-10, Vol.41 (10), p.2386-2394
Main Authors: Drenner, Ray W., Chumchal, Matthew M., Adams, Kimberly J., Seymour, Ryan D.
Format: Article
Language:English
Subjects:
Aquatic ecosystems
Bass
Bioaccumulation
Coniferous forests
Contamination
Deposition
Dimethylmercury
Ecoregion
Fish
Government agencies
Health hazards
Land cover
Largemouth bass
Mercury
Mercury (metal)
Methylmercury
Micropterus salmoides
Pasture
Southeastern United States
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Consumption of methylmercury (MeHg)‐contaminated fish is the primary source of MeHg in humans and poses a hazard to human health. Because of widespread atmospheric deposition of inorganic mercury (IHg), all water bodies in the United States have been contaminated with Hg. In aquatic ecosystems, IHg is converted to MeHg, which biomagnifies, reaching high concentrations in piscivorous fish. It is not possible for governmental agencies to monitor fish from every waterbody to determine if concentrations of MeHg in fish are hazardous to human health. To help government agencies focus their monitoring efforts, it is critical that we develop the ability to predict regions where waterbodies are most likely to contain fish with hazardous concentrations of MeHg. The objective of the present study was to examine the relationship between MeHg contamination of largemouth bass (Micropterus salmoides), a popular piscivorous gamefish, and land cover in 24 ecoregions across 15 states in the southeastern United States. In our study we demonstrate for the first time that 72% of the variance in average concentrations of MeHg in largemouth bass between ecoregions of the southeastern United States can be explained by the percentage coverage by evergreen forests, emergent herbaceous wetlands, and pasture/hay. Land cover determines the sensitivity of freshwater systems to atmospheric IHg deposition, and the present study suggests that at the ecoregion scale, MeHg bioaccumulation in piscivorous gamefish, and ultimately the health hazard that these MeHg‐contaminated fish pose to humans, can be in part predicted by land‐cover type. Environ Toxicol Chem 2022;41:2386–2394. © 2022 SETAC
ISSN:0730-7268
1552-8618
DOI:10.1002/etc.5426