Derivation of site-specific selenium water quality criteria: A comparison of two methods and regulatory implications.

In 2016, the US Environmental Protection Agency (USEPA) issued revised aquatic life water quality criteria for selenium (Se). The criteria ("elements") consisted of threshold concentrations applicable to fish tissue (three tissue types, though the egg and ovary tissue takes precedence over the whole-body and muscle tissue thresholds), and water column. The agency rationalized that measured concentrations of Se in fish tissue were more predictive of potential adverse reproductive effects than those measured in external media.

Selenium and mercury in freshwater fish muscle tissue and otoliths: a comparative analysis.

Evaluating potential ecological and human health risks of exposure to bioaccumulative trace elements is typically implemented using analysis of tissue samples. Increasingly, the microchemistry of fish calcified structures is used to elucidate the lifetime exposure to trace elements. In the present study, we measured total mercury (THg), methylmercury (MeHg), and selenium (Se) in muscle tissue and otolith samples from 12 species of fish collected at reference sites and locations influenced by power plant wastewater.

Bioavailability of mercury in power plant wastewater and ambient river samples: Evidence that the regulation of total mercury is not appropriate.

Mercury (Hg) is a neurotoxin that can cause debilitating effects to human and environmental receptors under high exposure conditions. For industrial and municipal point sources that discharge Hg, wastewater limitations on total Hg (THg) concentrations or loads are typical. While this regulatory practice provides simplicity for regulated industry and water resource agencies (i.