Our current crisis reaffirms the importance of weighing the health benefits of eating fish against chemical exposure risks.
Even in the best of times, spring's long days, warming temperatures, greening landscapes, and sunshine represent a time of growth and optimism—a time to open windows, go outdoors, perhaps even try one's hand at gardening or fishing.
This spring, during a moment in history that will be remembered for its uncertainty, the arrival of spring feels especially welcome and fishing is among the activities that people will be engaged in as the weather warms.
For some, fishing is a means of outdoor recreation. For others, it is a livelihood. And for others, it represents an affordable way to meet their nutritional needs—especially pressing now, given the economic hardship and potential supply-chain disruptions brought on by the novel coronavirus virus.
Since the pandemic began, grocery store fish and shellfish sales in the United States have risen and the consumption of self-harvested fish and shellfish may also increase as a result of this pandemic.
Changes in dietary patterns have public health and environmental implications, and it is important for health and environmental professionals to consider revisiting the usual approach to weighing benefits and risks of fish and shellfish consumption to better reflect a full scope of considerations during the COVID-19 pandemic.
In some cases, this may mean shifting the narrative around fish consumption advisories from the current harm-prevention framework, to more of a risk-reduction model.
Fish advisory sign in Monroe County, Indiana. (Credit: Wikimedia Commons)
Shortcomings in current advisories
Fish consumption presents a critical tradeoff to consumers even under normal circumstances.
Fish are a major source of protein and omega-3 polyunsaturated fatty acids, a class of lipids associated with a wide range of health benefits, including decreased risk of cardiovascular disease.
Unfortunately, environmental contaminants accumulate in fish tissue, posing health risks to consumers.
Contaminants known to be associated with adverse health effects that are commonly found in fish include methylmercury; per- and polyfluoroalkyl substances (PFAS); polychlorobiphenyls (PCBs); and other organochlorines.
In the U.S., state agencies use a traditional risk assessment process to establish fish consumption advisories. The process is predicated on harm prevention and estimates how much fish can safely be consumed from a specific body of water or region that is contaminated.
The advisories state the frequency with which fish servings of a given size (e.g., two 4-oz servings of locally-harvested trout per month) should be consumed by sensitive populations—usually women of child-bearing age and young children.
While fish consumption advisories are considered best practice for protecting fish consumers there are key shortcomings. Common limitations include:
- The risk-only approach, which does not adequately address the trade-offs between health benefits and risks,
- The individual-chemical approach used for calculating advisories, which addresses each contaminant but does not account for the combined health effects of multiple chemicals,
- The cultural or personal significance of fish or shellfish in one's diet.
A Yakama Nation member fishing at the Horn Rapids in Washington State. Most current fish advisories don't account for cultural or personal significance of fish in one's diet. (Credit: Scott Butner/flickr)
For example, the evaluation of risks of mercury exposure and benefits of omega-3 polyunsaturated fatty acids improves the recommendations about fish species and vulnerable populations.
In the North American Great Lakes region, about half of advisories would be more stringent if they considered inter-chemical interactions.
Further, communities fish for different reasons. A study on residents of Robeson County, North Carolina, found that the African American and native Lumbee communities sought local fish for cultural reasons, whereas Latino community members procured local fish for reasons of economic necessity.
In sum, fish consumption advisories are not well-equipped to address the complex simultaneous cost-benefit analyses of fish consumption.
Despite these limitations, fish consumption advisories have proven effective in altering consumers' perceptions and behaviors.
- In Maine, a booklet mailed to residents increased women's knowledge of fish benefits and risks, as well as their ability to identify high-mercury and low-mercury fish.
- When urban anglers in the Great Lakes region were provided with a brochure outlining recommended fish consumption limits, those who previously exceeded advisory recommendations decreased their sport-harvested fish consumption, and those who previously ate very little sport-harvested fish increased their intake frequency.
- A decline in fish consumption was reported among pregnant women following the announcement of updated U.S. Food and Drug Administration guidelines aimed to reduce mercury exposure.
These results indicate that fish consumption advisories can be an effective tool if they contain clear, comprehensive recommendations.
Reevaluating advisories during the COVID-19 crisis
While the advisories attempt to balance the risks of contaminant exposure with the health-protective benefits of fish intake, the relative importance of these competing factors may shift given individual circumstances—or a global pandemic.
The COVID-19 pandemic has turned people's lives upside-down, including shifts in diet, lifestyle, and finances. Established fish consumption advisories are based on assumptions about fish consumers' behaviors and the availability of alternative sources of nutrition. Yet, the validity of these assumptions may be tested by cultural preferences or abrupt circumstantial changes such as natural disasters.
As individuals face economic hardship, disruptions in access to other protein sources, and the loss of recreation options, the relative benefits of fishing and of consuming self-harvested fish and shellfish may change in ways that existing consumption advisories did not anticipate.
As the pandemic and its fallout continues, health and environmental professionals need to reevaluate fish consumption advisories to ensure that they reflect the current needs of their constituents.
In some instances, this will require shifting the consumption advisories from a harm-prevention framework to a risk-reduction model. It is not reasonable, or even safe, to expect consumers to prioritize minimizing contaminant exposures if doing so will undermine their basic food security.
For example, public health professionals and risk assessors should consider making recommendations about where people can most safely fish and which species are safest to consume locally. This will help people minimize their risk of exposure to contaminants, while recognizing the importance of self- and locally-harvested fish in their lives.
Angler on the Milwaukee River. (Credit: Brandon Blanke/flickr)
Environmental and health authorities should consider prioritizing additional seafood tissue monitoring in 2020 to ensure that risk assessors and public health professionals have the best available data when making recommendations about areas where fish are the least contaminated.
Clinicians should consider asking patients whether their dietary patterns have changed during the pandemic, particularly changes in their reliance on self-harvested foods, including fish and shellfish.
Clinicians should also consider recommending that patients prioritize other sources of protein for members of their family who are most vulnerable— pregnant women; children; women of childbearing age—to the adverse effects of contaminants in fish.
Fish and game agencies and other environmental organizations should make additional efforts to publicize fish consumption advisories to ensure that anglers have the available information to make the best choices for themselves and their families. Distributing local advisories with fishing licenses and/or posting new signs in all languages commonly spoken in a region are examples of how the information could be better disseminated.
Researchers should consider asking questions about commercial and self-harvested fish and shellfish consumption patterns among participants in new and existing studies to document how the pandemic has affected fish consumption.
Finally, it is important for health and environmental professionals to identify their own communities' specific needs with respect to self-harvested fish. While we know that fishing confers many nutritional and psychological benefits, the salience of different benefits during the COVID-19 pandemic will vary across populations.
Advising the public effectively about fish consumption requires an understanding of the risks presented by contaminant exposures, but it also requires a willingness to listen.
Knowledge about environmental hazards is only as valuable as knowledge of their context, and as the context shifts, so must we all.
Kathryn Crawford is a Postdoctoral Research Associate at the Geisel School of Medicine at Dartmouth. Brittany Cleary is a Junior at Dartmouth College. Caredwen Foley is a graduate student at the Boston University School of Public Health, Wendy Heiger-Bernays is a Clinical Professor of Environmental Health at the Boston University School of Public Health.
Their views do not necessarily represent those of Environmental Health News, The Daily Climate or publisher, Environmental Health Sciences.
Banner photo: Fishing in New York City. (Credit: Liz/flickr)