A new report by the International Joint Commission (IJC) Health Professionals Advisory Board reviews the health risks that humans are exposed to when they frequently consume fish with high levels of the trace element selenium. Selenium is a naturally occurring, nutritionally essential trace element commonly found in a diet including foods like fish and nuts. Selenium also can be introduced to soil, water, or air as a by-product of various industrial processes like mining of coal and metals.
Chronic selenium exposure, called selenosis, can cause fatigue, can damage nails and hair, and can have some neurotoxic effects. The report outlines the selenium health criteria underlying governments’ efforts to develop guidelines to help fish consumers understand how much, and how often, they can eat fish and safely avoid chronic selenium exposure. “However, the scientific evidence for the health effects of selenium is not consistent, and that’s why there are different selenium intake limits recommended by different agencies in Canada and the United States,” said Dr. Laurie Hing Man Chan, Canadian co-chair of the Health Professionals Advisory Board. Dr. Laurie Hing Man Chan is also a professor and Canada research chair in toxicology and environmental health at the University of Ottawa.
The report also finds that regulation of selenium pollution in a waterway may not account for all other potential selenium sources. “To best protect public health, governments need to be regulating selenium throughout a watershed, including accounting for sources upstream and outside of their jurisdiction,” said Dr. Elaine Faustman, U.S. co-chair of the Health Professionals Advisory Board. Dr. Faustman is also a professor and director of the Institute for Risk Analysis and Risk Communication at the University of Washington. “A selenium-safe watershed is one where governments share information throughout the watershed and collaborate to harmonize thresholds for intake limits and action advisories.”
Source: Water Canada
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