Effects of lead exposure on birds breeding in the Southeast Missouri Lead Mining District

• DOI: 10.3133/sir20235032
• Publication Date: 2023-08-11T19:09:28Z
• Authors: Rebecka Brasso; Danielle Cleveland; Frank R. Thompson; David E. Mosby; Kathy Hixson; Melissa Roach; Barnett A. Rattner; Natalie K. Karoun...; Julia S. Lankton
• Keywords: Lead (geology); Lead smelting

First posted August 11, 2023 For additional information, contact: Director, Columbia Environmental Research CenterU.S. Geological Survey4200 New Haven RoadColumbia, MO 65201Contact Pubs Warehouse Lead mining in the Southeast Missouri Mining District began 1700s and continued for nearly 300 years; waste piles associated with smelting, mining, milling of lead ores have released metal residues that contaminated soil water region. Previous studies district indicated potential harm to wildlife, including birds, because elevated concentrations mining. Exposure soil-borne was correlated tissues, inhibition δ-aminolevulinic acid dehydratase (δALAD), renal lesions birds foraging on ground-dwelling invertebrates at sites (compared reference sites) District.This study assessed reproductive outcomes songbirds exposed district, examined relation between soils tissues ground-feeding prey species, compared results literature-based toxicity thresholds are negative effects birds. Three lead-contaminated three (with background no known inputs) were two ways: individually all other or by site type. Additional exposure evaluated examining biomarkers (oxidative stress, lipid peroxidation, deoxyribonucleic damage) liver δALAD inhibition, hepatic microscopic from sites.Lead site-dependent also generally heterogeneous within sites. Between 17 74 percent samples had exceeded a threshold (1,000 milligrams per kilogram [mg/kg] soil) previously adverse physiological District. mixed (282 2,230 mg/kg dry weight [dw]) consuming soil-dwelling species is pathway adult their broods. At sites, 40.5 blood (adults broods) subclinical range (0.9 2.3 dw), 18.7 clinical criteria (greater than dw). In contrast, only 2.6 lead; representative (less 0.9 Subclinical exceedances livers kidneys similarly more prevalent positively soil, livers, kidneys. negatively activity; greater 50 collected exhibited injury via Birds enhanced oxidative stress. Microscopic similar rates occurrence lesion prevalence could not be directly linked exposure. Reproductive success monitored 585 nests, 3 out 5 reduced nest soil; habitat measures did help explain success. Reduced may resulted predation resulting neurological behavioral Ultimately, these lines evidence indicate bird health reproduction been affected