Testing recommendations for heavy metals
EDF's testing recommendations for heavy metals
Companies should explicitly prohibit arsenic, cadmium, and lead in any packaging or food handling equipment, and strictly avoid the use of brass and bronze unless confident that no lead, arsenic or cadmium was added.
Companies should test food products, ingredients, and packaging for arsenic, cadmium, and lead. Specifically, companies should:
- Systematically test food products and ingredients that are potentially contaminated with arsenic, cadmium or lead using FDA’s approved method and investigate possible sources where measurable levels are found. In the instances where FDA has set a tolerance, investigate when levels are above one-tenth of the tolerance.
- Periodically test all packaging that contacts food anywhere along the supply chain for arsenic, cadmium, or lead using a CPSC-accepted, third-party certified lab that evaluates children’s products for lead using CPSC-approved methods Investigate any measured levels over 10 parts per million (ppm) for any one of the heavy metals.
NOTE: EDF is evaluating whether a portable X-ray fluorescence (XRF) meter and surface dust wipes would be effective methods to test food handling equipment as a source of arsenic, cadmium, or lead contamination in food. If you want to learn more, or may be interested in participating in that evaluation, please contact EDF.
Why test for heavy metals?
Heavy metals such as arsenic, cadmium, and lead pose an array of serious health risks, especially to children, and have no safe level in the diet. However, extensive environmental contamination from past uses as well as natural sources mean that the presence of heavy metals cannot be eliminated.
Many states have limits on the amount of heavy metals allowed in any packaging. FDA actively monitors the food supply for heavy metals and routinely finds them in various foods, including high levels in some imported foods.
Given the potential health consequences, regulatory compliance needs, and the media attention that heavy metals can draw, food manufacturers and retailers need to use best practices to reduce heavy metals to the greatest extent possible. One of these best practices is systematic testing of food products, ingredients, packaging, and handling equipment for contamination.
The problem with heavy metals: A deep-dive
Why are heavy metals important?
Heavy metals are elements; they never go away. As a result of their extensive presence in the environment from natural sources and human activities, virtually all Americans have arsenic, cadmium, lead and mercury in their body. Once in our body, they can cause harm at even low levels that were once considered “safe.” Children, with their developing bodies and brains, are particularly vulnerable.
Based on these concerns, FDA has prioritized heavy metals, stating that it is “taking a systematic approach to reduce the risks posed by these metals especially to vulnerable populations such as infants and children, who are most susceptible to some of the harmful neurological and developmental effects.”
EDF has prioritized three heavy metals – arsenic, cadmium, and lead – because significant opportunities exist to reduce their levels in food through improved best practices. Our work to reduce exposure to lead in food has synergies with our other efforts to reduce lead exposure. While mercury is a potent neurotoxin, it is most commonly found in fish and opportunities to reduce those levels through best practices other than selecting different types of fish are limited.
Below are key health concerns associated with exposure to EDF’s priority heavy metals:
- Lead: Impaired brain development and lower IQs in children; cardiovascular disease; and cancer.
- Inorganic arsenic: Impaired cognitive development in children; cardiovascular disease; diabetes; and cancer.
- Cadmium: Kidney disease; cardiovascular disease; and cancer. A better understanding is needed of the neurological impacts of cadmium exposure.
Are heavy metals really in food?
While tremendous progress has been made in controlling or eliminating human-made sources of heavy metals such as lead arsenate pesticides, the legacy of these activities as well as natural sources have left soil and water contaminated. As a result, arsenic, cadmium, and lead migrate into our food supply. Through its Total Diet Study, FDA has systematically tested most foods for heavy metals for decades and regularly made the results publicly available. In early 2019, an FDA estimate of young children’s cumulative dietary intake of lead and cadmium showed heavy metal exposure to be a significant concern.
The following shows the foods most likely to be contaminated by:
- Lead: The primary source of contamination appears to be soil, where the lead migrates into root crops such as sweet potatoes and carrots, or can contaminate produce such as grapes, raisins, apples, and squash. While still significant, these levels are usually relatively low at less than 100 parts per billion (ppb). Lead may also be found at significantly higher levels in some ingredients such as spices or carrageenan, especially where human-made sources have not been well-controlled.
- Arsenic: Fish followed by rice have significant arsenic contamination. Fish contamination is most likely from natural sources. Other foods may also be contaminated from soil contaminated by decade-old treatment with lead arsenate pesticide.
- Cadmium: Similar to lead, contaminated soil appears to be the primary source of cadmium in the diet.
Are heavy metals still intentionally used in food contact materials?
Yes, although FDA does not explicitly authorize the use of arsenic, cadmium, or lead in food contact materials.
Most intentional uses of these heavy metals in food contact materials have been eliminated. Lead in tableware was banned in 1980, and lead solder on metal food cans finally ended in the 1990s. Nonetheless, lead is still added to most brass and bronze where it can leach or be abraded into food. For example, the NSF/ANSI 51 standard explicitly allows lead up to 0.25% (2500 ppm) for these materials in contact with tea, coffee, or water. Similarly, the NSF/ANSI 61 standard explicitly recognizes that lead leaches from brass or bronze drinking water fixture such as faucets and valves, allowing as much as an average of 5 micrograms to lead in an overnight sample of water during the first three weeks of use.
Lead may also still be present in polyvinyl chloride plastic fixtures installed before the industry phased it out in the 2000s.