Chemical contaminants in U.S. freshwater fish exceed pollution standards despite regulations

According to a recent study published in Environmental Research, individuals who consume U.S. freshwater fish are exposed to a mixture of chemical contaminants that can have combined health effects.


In short:

  • In addition to mercury, these pollutants include chemicals such as PFAS and legacy contaminants like PCBs, which are no longer produced.
  • Researchers found a correlation between the presence of organic chemicals (including PCBs and PFAS) in fish tissue, but no correlation between those chemicals and mercury.
  • Although the presence of some organic chemicals declined over time, mercury levels have not decreased, and some chemical levels still exceeded the minimum for risk-based screening despite being banned decades ago.

Key quote:

“Despite some successes in curtailing release of pollutants, some contaminants in fish tissue have not declined and legacy and emerging pollutants continue to pose risks to fish consumers in the U.S.”

Why this matters:

While freshwater fish are an important food source for both people and wildlife in the U.S., their consumption poses a threat to public health due to the accumulation of environmental toxics in their tissues. Most regulations focus only on individual contaminants rather than chemical mixtures, and fish consumption advisories are frequently driven solely by mercury levels, missing potential exposures to many other pollutants. The authors of this study call for stronger legislative and regulatory efforts at both the state and federal level to protect consumers and reduce ongoing contamination.

Related EHN coverage:

More resources:

Wu, Pianpian et al. for Environmental Research vol. 266. Feb. 1, 2025

About the author(s):

Katherine McMahon
Katherine McMahon
Katherine McMahon is a Science Administrative Assistant at Environmental Health Sciences.
Sarah Howard
Sarah Howard
Howard is the Program Manager at Healthy Environment and Endocrine Disruptor Strategies (HEEDS), a program of Environmental Health Sciences.

You Might Also Like

Recent

Top environmental health news from around the world.

Environmental Health News

Your support of EHN, a newsroom powered by Environmental Health Sciences, drives science into public discussions. When you support our work, you support impactful journalism. It all improves the health of our communities. Thank you!

donate