Mercury and methylmercury distribution in tissues of sculpins from the Bering Sea

Abstract

Fish skeletal muscle is often used to monitor mercury concentrations and is used by regulatory agencies to develop fish consumption advisories. However, the distribution of mercury species (MeHg+ and THg) in muscle tissue and other organs is not well understood in a number of fish species. Here we evaluate the spatial distribution of THg and MeHg+ in skeletal muscle and internal organs (heart, liver, and kidney) of 19 sculpin representing three species: Myoxocephalus scorpius (shorthorn sculpin n = 13), Myoxocephalus jaok (plain sculpin, n = 4), and Megalocottus platycephalus (belligerent sculpin, n = 2). Four subsamples of muscle were taken along the lateral aspect of each fish, from muscle A (cranial) to muscle D (caudal). Using Games–Howell post hoc procedure to compare mean concentrations of all tissues, muscle samples were significantly different from internal organs, although there was no difference between muscle-sampling locations. THg concentrations (ww) were higher in muscle (muscle A through D mean ± SD, 0.30 ± 0.19 mg/kg) than that in heart (0.06 ± 0.05 mg/kg), kidney (0.08 ± 0.06 mg/kg), and liver (0.09 ± 0.08 mg/kg). Percent MeHg+ decreased with age in both skeletal muscle and organs (p < 0.05). In contrast to some previous reports for other fish species, this study found significantly higher THg concentrations in muscle than in the liver. This study highlights the importance of using muscle samples when evaluating potential Hg exposure in risk assessments for piscivorous wildlife and human populations, and assumptions related to organ mercury concentrations should be examined with care.

Contrasting trophic transfer patterns of cadmium and mercury in the Arctic marine food web of east Hudson Bay, Canada

“…For the analysis, we used measured values for MeHg concentrations for a subset of ringed seal liver ( n = 13). We calculated MeHg concentrations in the liver of Arctic cod, sculpin, and common eider by multiplying the THg concentration in the liver by the average proportion of MeHg in the liver for each species (0.75, 0.50, and 0.81, respectively) reported in literature (Harley et al 2015 ; Wayland et al 2001 ). When we refer to models that include both THg and MeHg data, we simply use “Hg” when describing the results.…”

Contamination of soils with Cu, Na and Hg due to the highway and railway transport

“…In contrast, mercury is present in soil only in trace amounts and is considered as a polluting element with toxic effect on all organisms. Mercury is the volatile element; its ability to form toxic alkylmercury derivatives is well-known (Harley et al, 2015;King et al, 2002).…”

A human-health risk assessment of dietary methylmercury exposure in Fort Albany First Nation

“…The assessment of mercury in fish species that are readily consumed by First Nations communities such as Fort Albany First Nation are crucial for monitoring the well-being of the population and the species within the Albany River. In humans, and species present in the aquatic ecosystems, methylmercury is of great concern due to the ability to bioaccumulate and biomagnify in aquatic systems, along with its potential to be absorbed and distributed to tissues (Harley et al, 2015;Wolfe, Schwarzbach, & Sulaiman, 1998). A standard from the Health Canada consumption guideline for total mercury in fish tissue of 0.5 µg/g wet weight (0.5 µg/g = 2.4925 nmol/g) was used respectively.…”