A longitudinal study of mercury exposure associated with consumption of freshwater fish from a reservoir in rural south central USA

Abstract

Methylmercury (MeHg) exposure through fish consumption is a worldwide health concern. Saltwater fish account for most dietary MeHg exposure in the general U.S. population, but less is known about seasonal variations in MeHg exposure and fish consumption among millions of freshwater anglers. This longitudinal study examined associations between MeHg exposure and fish consumption in a rural, low-income population relying on a freshwater reservoir (Oklahoma, USA) for recreational and subsistence fishing. We interviewed 151 participants, primarily anglers and their families, seasonally for one year using 90-day recall food frequency questionnaires to assess general and species-specific fish consumption, and tested hair biomarker samples for total mercury (THghair). Mean THghair was 0.27 μg/g (n=595, range: 0.0044–3.1 μg/g), with 4% of participants above U.S. EPA's guideline for women of childbearing age and children. Mean fish consumption was 58 g/d (95% CI: 49–67 g/d), within the range previously reported for recreational freshwater anglers and above the national average. Unlike the general U.S. population, freshwater species contributed the majority of fish consumption (69%) and dietary Hg exposure (60%) among participants, despite relatively low THg in local fish. THghair increased with fish consumption, age, and education, and was higher among male participants and lowest in winter. Our results suggest that future studies of anglers should consider seasonality in fish consumption and MeHg exposure and include household members who share their catch. Efforts to evaluate benefits of reducing Hg emissions should consider dietary patterns among consumers of fish from local freshwater bodies.

Key contributors to variations in fish mercury within and among freshwater reservoirs in Oklahoma, USA

“…Most of the species are commonly consumed by local residents 50 or are sport fish. Around 68% of these fish were collected by the Oklahoma Department of Wildlife Conservation (ODWC) as part of routine fish population surveys, primarily using gill nets.…”

Levels of nutrients in relation to fish consumption among older male anglers in Wisconsin

“…This possibility is particularly important in nutritional public health when examining risk factors for clinically depressed or elevated nutrient levels. One approach to examine the possibility of differing predictor effects at different response levels, is quantile regression (Koenker and Bassett 1978, Dong, Jim et al 2015). With this approach, the response being modeled is the conditional quantile (rather than the mean) of the outcome; rather than estimating a single slope, multiple slopes are estimated for different (conditional) levels of the outcome, providing a more complete picture of the effect of exposure on different levels of the outcome of interest.…”

Benefits of Fish Consumption for Healthy and Balanced Nutrition During Lifelong Time

“…Cıva, doğada yaygın olarak bulunan bir kirleticidir ve çeşitli formları mevcuttur. Cıvanın özellikle metillenmiş formu olan MeHg insanlarda nörotoksisite ile ilişkili olup fetüs ve çocuklar üzerinde çok ciddi olumsuz etkileri mevcuttur (Dong et al, 2015). MeHg'nin kaynağı çoğun-lukla sucul ortamdır.…”

“…Katılımcıların %4'ünün saçlarındaki ortalama cıva düzeyi, ABD'nin doğurganlık çağındaki kadınlar ve çocuklar için önerdiği Çevre Kirliliği Kurumu (EPA) rehberinin belirttiği limitler üzerinde bulunmuştur. (Dong et al, 2015).…”