Mercury in Food

For Those Who Might Become or Are Pregnant or Breastfeeding and Children Ages 1 - 11 Years

Mercury may be present in food from the environment where foods are grown or raised. Levels of mercury in the environment can vary depending on natural geographical makeup and proximity to current or past use or manufacturing of products made with mercury. For example, mercury can be distributed in the environment from volcanic activity, geological weathering, and can be higher in areas as a result of fossil fuel combustion, manufacturing, and small-scale gold mining.

The FDA monitors and regulates levels of mercury in foods. Because the very young are more vulnerable to the harmful health effects of mercury exposure, and because seafood is the most common way people are exposed to mercury, the FDA and the Environmental Protection Agency (EPA) have issued advice on eating fish.

Among the FDA’s top priorities is maintaining access to foods that are sources of nutrients while limiting consumer exposure to contaminants. Having adequate nutrition is vital to growth and development for babies and children and helps promote health and prevent disease throughout our lifespan. The FDA collaborates with state and federal partners, industry, and other stakeholders to identify and facilitate the implementation of sustainable and effective strategies for growing, sourcing, processing, and manufacturing foods that contain lower levels of environmental contaminants, such as mercury, while maintaining their nutritional quality and accessibility.

For more information about the FDA’s specific activities to reduce exposure to arsenic, lead, mercury, and cadmium from foods consumed by babies and young children, please visit the Closer to Zero page.

General Information

The most common way people in the U.S. are exposed to mercury is by eating seafood contaminated with methylmercury. Nearly all fish and shellfish contain trace amounts of methylmercury. While it is not possible to prevent methylmercury from entering seafood or remove methylmercury from seafood, most types do not have levels that would result in health effects for adults.

Because the very young are more vulnerable to the harmful health effects of mercury exposure, and because there are significant differences in the levels of methylmercury between different types of seafood, the FDA and EPA have issued advice on eating fish. This advice can help those who are or might become pregnant or are breastfeeding, as well as parents and caregivers who are feeding children, choose types of seafood that are lower in methylmercury and provide key nutrients that support child development of the brain, spinal cord, and immune system. This advice supports the recommendations of the Dietary Guidelines for Americans.

The advice features a chart that makes it easy to choose dozens of healthy and lower methylmercury options and includes information about the nutritional value of fish. A set of frequently asked questions & answers provides more information on how to use the chart and additional tips for eating fish.

Resources from the FDA

Resources from Other Federal Government Agencies

Health Effects Information

Methylmercury, the most abundant form of mercury found in seafood, is the most potentially harmful form of mercury and can affect people of any age or health status. The potential for long-term adverse health effects from consuming food contaminated with methylmercury vary depending on the amount consumed; age of the consumer; length, amount, and frequency of exposure to methylmercury in the food; and other exposures happening at the same time—either to mercury from other sources, other contaminants, or to beneficial nutrients.

Exposure to high levels of methylmercury during times of active brain development can lead to neurological effects such as decreased measures of intelligence, difficulty in memory and cognition, and problems with gross and fine motor skills. Evidence is also emerging that attention could be impacted. Fetuses, infants, and children are particularly vulnerable to the potential harmful effects from methylmercury exposure because of their smaller body sizes and rapid growth and metabolism.

Adverse short-term health effects for adults from consuming average amounts of seafood usually require a level of methylmercury not generally found in seafood products. For adults exposed to harmful levels of methylmercury, symptoms of poisoning may appear over time or may develop suddenly. They may include a range of symptoms such as psychological issues (e.g., depression or memory problems), numbness or muscle weakness (e.g., difficulty walking); difficulty with speech, hearing, or vision; a “metallic” taste in the mouth; and issues with balance. Suspected methylmercury poisoning should be diagnosed by a physician after testing for the level of mercury in a person's blood or urine.

More information about health effects can be found by visiting the Centers for Disease Control and Prevention (CDC).

Scientific Information

The FDA tests food for environmental contaminants, like mercury, to monitor the safety of the U.S. food supply, enforce FDA regulations, inform agency guidance to industry, and provide the public with accurate, science-based information. Testing may be targeted to a specific category of food, such as foods commonly eaten by children under 2 years of age, or to a specific food or food group. Testing may also be conducted in response to reports of elevated contaminant levels in certain foods. Testing may occur at FDA laboratories, laboratories we contract with, or at state laboratories as part of our cooperative agreement with states.

The FDA tests for environmental contaminants, including mercury through:

the Total Diet Study;
the FDA’s Toxic Elements in Food and Foodware, and Radionuclides in Food compliance program; and
Other surveys, which may be conducted annually or in response to reports of elevated contaminant levels in certain products or to focus on a specific food or food group.

Current Research

Testing Results

The FDA has conducted routine surveillance and targeted surveys for arsenic, lead, cadmium, and mercury in foods, including those commonly consumed by babies and children under 2 years of age.

Analytical Results for Arsenic, Lead, Cadmium, and Mercury in Foods Intended for Babies and Young Children- TEP (FY2008-FY2021) in PDF, in XLSX
Sampled under the FDA’s Toxic Elements in Food and Foodware, and Radionuclides in Food – Import and Domestic Compliance Program, Posted March 2023

Testing Methodology

The FDA has been conducting research to optimize testing methods to measure increasingly smaller amounts of environmental contaminants in foods commonly eaten by babies and young children.

For more information, please visit: A survey of toxic elements in ready to eat baby foods in the US market 2021 (2022).

Seafood and Child Growth and Development

To evaluate the scientific evidence regarding seafood and child growth and development to support a more holistic view of seafood consumption, the FDA launched an independent study by the National Academies of Sciences, Engineering, and Medicine (NASEM).

For more information, please visit: FDA and Federal Partners Launch Study on the Role of Seafood Consumption in Child Growth and Development.

Scientific Articles and Reports

Past Research

Testing Results

From 1990-2010, the FDA sampled and tested fish and other seafood for mercury. The results of this 20-year survey showed that mercury levels did not change significantly over time. For data on mercury levels (concentrations) from 1990-2010, please visit:

Past Risk Assessments

International Scientific Activities

FDA experts participate in the international standard-setting body, Codex Alimentarius Commission (Codex). The purpose of Codex is to protect the health of consumers and promote fair trade practices by adopting scientifically based standards, guidelines, and codes of practice across all areas of food safety and quality. Its work includes reviewing the scientific data concerning contaminant levels in foods. These international discussions can lead to recommendations for standards individual countries may adopt and codes of practice to prevent or reduce the presence of contaminants in food.

Regulatory Information

Federal Regulations

There are no FDA regulations that authorize mercury for use as a color additive or food additive. Because mercury is widespread in the environment, and because it is not possible to remove mercury from seafood, or to grow or produce certain foods completely free of mercury, the FDA’s goal is to limit consumer exposure to mercury, with a focus on protecting the very young, through developing regulations, setting action levels, and issuing advice to consumers.

It is the legal responsibility of companies that grow or produce foods, or manufacture products intended for use with foods sold in the U.S., to comply with the Federal Food, Drug, and Cosmetic Act and FDA’s regulations.

If the FDA determines that the level of mercury causes the food to be unsafe, the agency will take regulatory action. This may include working with the manufacturer to resolve the issue, and as necessary, taking steps to prevent the product from entering, or remaining, in the U.S. market.

Bottled Water: The FDA limits the level of mercury (as well as other contaminants) in bottled water by establishing allowable levels in the quality standard for bottled water. For mercury, this level is set to 2ppb, the same amount allowed by the U.S. Environmental Protection Agency for public drinking water.

Import Alerts

The FDA issues import alerts to prevent potentially violative products from being distributed in the United States. The agency has issued import alerts for certain foods and products from certain manufacturers that may pose a food safety hazard due to the presence of elevated levels of mercury.

Import Alert 99-42 for heavy metal (including mercury) contamination of foods

Guidance for Industry

The FDA issues guidance for industry to describe the agency’s current thinking on a regulatory issue. For example, guidance on action levels communicates to industry the level of contaminants in foods at which the FDA may take enforcement action. Unlike regulations, guidance is not legally binding for the FDA or industry.

Guidance for Industry: Action Levels for Poisonous or Deleterious Substances in Human Food and Animal Feed
August 2000

Compliance Policy Guides

The FDA issues compliance policy guides for FDA staff to assist in their evaluation of evaluating industry compliance with FDA safety requirements. These guides are intended for FDA use but are made publicly available.