Regulating Heavy Metals in Baby Food: The Challenges of Food Manufacturers and the FDA Being on the Same Page

Spectroscopy, Spectroscopy-07-01-21, Volume 36, Issue 7
Pages: 10–16

A recent report by the Subcommittee on Economic and Consumer Policy of the Committee on Oversight and Reform of the US House of Representatives found that processed baby foods from seven of the largest manufacturers are tainted with dangerous levels of arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg). The report was based on internal documentation the subcommittee requested from these companies in November 2019, following an investigation alleging high levels of toxic heavy metals in both organic and conventional processed baby food cereals in 2018. Based on the report, it was clear that the companies had few concerns about the elevated levels of heavy metals in their products and, in many cases, ignored their own internal testing limits. This article takes a closer look at the congressional report and its recommendations to the Food and Drug Administration (FDA) to reduce heavy metals in baby food to acceptable levels within two years. We also review the challenges and practicalities of scrutinizing the food industry that has historically been allowed to regulate itself.

The recent report published by the Subcommittee on Economic and Consumer Policy of the Committee on Oversight and Reform of the House of Representatives highlighted that processed baby foods from seven U.S. manufacturers had unacceptable levels of arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg) in their baby food products. The congressional report was generated based on information the subcommittee requested from these companies in November 2019 following an investigation in 2018 alleging high levels of toxic heavy metals in both organic and conventional processed baby food cereals (1).

Not all food companies responded to the request, but for those who did, it was a critical assessment of the way they went about testing their products that relied mainly on sampling the raw materials and ingredients. However, very few of the food companies mentioned in the report actually tested the final products that went on supermarket shelves. Based on the congressional report, it was clear that the companies had little concern about the elevated levels of heavy metals in their products. In many cases, they had their own internal quality control checks, but there were no repercussions if their products didn’t meet the requirements. Let’s take a closer look at the congressional report and, in particular, its recommendations to the U.S. Food and Drug Administration (FDA). We then take a deeper dive into the challenges and practicalities of scrutinizing an industry that has historically been allowed to regulate itself. Let’s begin by focusing on the baby foods and the heavy metals highlighted in the report.

Arsenic

Rice is a very common constituent in baby food cereals. It is typically grown in flooded fields; as a result, rice tends to contain high levels of arsenic associated with it because the water dissolves the arsenic out of the soil, which in turn gets absorbed by the root system in plants. For that reason, infant cereals made from rice typically have higher levels than other processed baby foods. The U.S. FDA has set a maximum limit of 100 ppb for inorganic arsenic in rice cereal. However, many of the infant foods of the companies that supplied data had levels up to 3–4x higher than the FDA regulated limits, and one baby food had over 900 ppb level of arsenic. It’s worth pointing out why inorganic arsenic is so important. In 2012, Dr. Mehmet Oz, the famous television doctor, alarmed his viewers about high levels of arsenic in apple juice. However, what he failed to say was that it was not the highly toxic inorganic forms of arsenic, such as pentavalent (As5+) and trivalent (As3+), but the relatively innocuous organic forms of arsenic including methyl arsonic acid (MAA), dimethyl arsinic acid (DMA), and arsenobetaine that had been metabolized by the apple tree. For this reason, inorganic arsenic is the form that is usually regulated, because of its higher toxicity (2).

Lead

Lead (Pb) was another element that was abnormally high in baby foods. The FDA does not regulate lead in processed baby food but has set limits of 100 ppb for lead in candy and 50 ppb for lead in fruit juices. In addition, the FDA has set a limit of 5 ppb for lead in bottled drinking water. Every baby food tested showed levels of at least 20–50 ppb, and one product was as high as 800 ppb. The report also revealed that another producer had six samples that showed over 200 ppb for lead. It’s worth pointing out that the major source of lead in vegetables and farming crops is usually as a result of tetra ethyl lead being used as a gasoline additive for decades, resulting in the contamination of much of the farmland in the United States, particularly around major highways (3). Moreover, we have used lead paint for decades, which is still a problem today in older buildings even though it was banned in 1978. In addition, many of the service lines used in our drinking water supply are made from lead or copper joined with lead-based solder, which have all contributed to high levels of lead in the environment (4).

Cadmium

In addition, cadmium was also present at high levels in baby foods made by all the companies that responded. There are no maximum limits for cadmium, but a 2019 FDA study found that 20 ppb was a fairly typical level in infant food. However, many of the baby foods were found to have in excess of 50 ppb and one in particular had over 300 ppb. Cadmium is another element that occurs naturally in soil and can easily get absorbed into a plant root system, especially if the pH and soil chemistry are favorable (5). In addition, cadmium, lead, and arsenic are commonly found in phosphate-based fertilizers, and some pesticides used to spray on apples and potatoes contain lead arsenate (6).

Mercury

It was difficult to assess the impact of mercury because only one company responded with a sample in excess of 10 ppb for mercury. The problem is that mercury is not an easy element to measure, and there are no regulated limits for mercury in baby food, so it is very difficult to know what is an elevated level. However, the FDA has set a limit of 2 ppb for mercury in bottled water, which is the same as the Environmental Protection Agency (EPA) maximum contaminant limit for drinking water. Therefore, any values over 2 ppb should be considered elevated. It’s also important to emphasize that mercury is one of the most serious pollutants emitted from power plants. It occurs naturally in fossil fuels; when coal is combusted, elemental mercury is emitted into the environment and pollutes the soil. The EPA estimates that about 50 tons of elemental mercury are emitted each year from U.S. coal-burning power plants, where it gets washed into rivers and lakes, and gets converted to methyl mercury by aquatic species and gets biomagnified up the food chain to the larger predator-type fish. That’s why mercury levels in canned tuna have been reported as a high as 200 ppb (7).

Report Summary

The results outlined in the congressional report suggested that levels for all the heavy metals in the baby foods were excessive even though only inorganic arsenic had an FDA regulated maximum impurity in rice cereal of 100 ppb (8). However, when the data were compared to allowable limits in bottled water, the levels were quite staggering, as seen in Table I.

Recommendations

The congressional subcommittee made it clear that ingredient testing by these companies is inadequate, and that only final product testing can measure the true danger posed by baby foods. It also didn’t help that the FDA took no action in response to these elevated levels. To this day, baby foods containing these toxic heavy metals have no label to warn parents of the dangers. Manufacturers are free to test only the raw materials and ingredients that go into the foods with no requirement to test the final products. In many cases, there was no testing done at all. In fact, the FDA has only regulated one metal for one category of baby food, setting a maximum limit of 100 ppb inorganic arsenic for infant rice cereal.

The subcommittee made the following recommendations (8):

  • Mandatory testing: Baby food manufacturers should be required by the FDA to test their finished products, not just their ingredients, for toxic heavy metals.
  • Labeling: Manufacturers should be required by the FDA to report levels of toxic heavy metals on food labels.
  • Voluntary phase-out of toxic ingredients: Manufacturers should voluntarily find substitutes for ingredients that are high in toxic heavy metals or phase out products such as rice that have high amounts of ingredients that frequently test high in toxic heavy metals.
  • FDA standard: The FDA should set maximum levels of toxic heavy metals permitted in baby foods. One level for each metal should apply across all baby foods, and the level should be set to protect babies against the neurological effects of toxic heavy metals.
  • Parental vigilance: Instituting recommendations will give parents the information they need to make informed decisions to protect their babies. Currently, parents should avoid baby foods that contain ingredients testing high in toxic heavy metals, such as rice.

Baby Food Safety Act of 2021

These recommendations are the basis of a new bill sponsored by Representative Raja Krishnamoorthi (D-IL), Senator Amy Klobuchar (D-MN), Senator Tammy Duckworth (D-IL), and Representative Tony Cárdenas (D-CA) (9). The bill emphasizes very strongly that baby food manufacturers hold a special position of public trust with U.S. consumers who believe that the federal government should not knowingly allow the sale of unsafe baby food. As this congressional report reveals, baby food manufacturers, together with federal regulators, have mostly failed to do this. Many baby foods contain high levels of toxic heavy metals, and there is currently no existing law or regulation to reduce their presence in baby food.

The Baby Food Safety Act would require manufacturers and the FDA to take the following six actions:

  • Setting the following maximum levels of heavy metals in baby food that manufacturers would have to meet within one year: inorganic arsenic (10 ppb for regular baby food, 15 ppb for cereal), lead (5 ppb for regular baby food, 10 ppb for cereal), cadmium (5 ppb for regular baby food, 10 ppb for cereal), and mercury (2 ppb for both). These limits are shown in Table II, where they are compared with current food-based heavy metals regulations together with bottled and tap drinking water limits from the FDA and EPA.
  • Requiring those levels to be lowered further within two years through FDA guidance and again after three years through regulation.
  • Requiring manufacturers to test their final products, not just ingredients, for toxic heavy metals (ingredient testing significantly underestimates toxic heavy metal levels).
  • Requiring manufacturers to post the results of their product testing online twice per year.
  • Establishing a public awareness campaign through the Center of Disease Control (CDC) to highlight the risks posed by toxic heavy metals in baby food.
  • Authorizing $50 million for research on agricultural methods of reducing toxic heavy metals in crops.

Parents expect the baby food sold on supermarket shelves to be safe and nutritious for their children. The goal of this legislation is to reduce toxic heavy metals in baby food, educate parents about the risks, and invest in cutting-edge farming technology to reduce any economic barriers to making baby food safe for consumption. As a result of this new bill, the FDA released an action plan for reducing exposure to toxic elements in baby foods. Below is an overview of their strategic plan regarding how they will achieve this (10).

FDA Action Plan

The FDA action plan entitled “Closer to Zero” aims to reduce exposure to toxic elements in foods commonly eaten by babies and young children to the lowest possible levels. Although the FDA’s testing shows that children are not at an immediate health risk from exposure to toxic elements at the levels found in foods, they are starting the work immediately, with both short- and long-term goals for achieving continued improvements in reducing levels of toxic elements in these foods over time. They recognize that Americans want zero toxic elements in the foods eaten by their children. However, in reality, because these elements occur naturally in the environment, there are limits to what can be achieved. Therefore, the FDA’s goal is to reduce the levels of arsenic, lead, cadmium, and mercury in these foods to the greatest extent possible. They are also sensitive to the fact that currently these levels are not feasible, and as a result, imposing these limits could mean significant reductions in the availability of nutritious, affordable foods that many families rely on for their children. Their plan, therefore, outlines a multiphase approach to achieving the goal of getting levels of toxic elements in foods closer to zero over time, which will include:

  • evaluating the scientific basis for action levels
  • proposing limits
  • consulting with stakeholders
  • finalize action levels.

Then, once the FDA has published final action levels, the agency will establish a timeframe for assessing industry progress toward meeting the action levels and re- commence the cycle to determine if the scientific data support efforts to further adjust the action levels downward.

A Deeper Dive: Toxicity Impact of Heavy Metals in Food

Let’s take a deeper dive into the sources of heavy metals in our food supply to better understand what food manufacturers and the FDA are up against. Foods made from vegetables, fruits, nuts, grains, and cereals are going to contain essential nutrients and other elemental constituents, such as calcium (Ca), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), and nickel (Ni) from the soil (11). Unfortunately, the plants are also going to absorb heavy metals, such as arsenic, lead, cadmium, and mercury. The phytoremediation properties of cannabis and hemp are an unfortunate testament to this fact. The cannabis plant is used as a source of cannabinoids for medicinal and recreational consumer products, but industrial hemp is used to clean up heavily contaminated soils (12). As a result, it is inevitable that any heavy metals in the soil will end up in the raw materials used to make the baby food cereals. The problem is that arsenic, lead, cadmium, and mercury are the most toxic of these metals and can lead to severe health problems with regular and long-term exposure to them. They can interact with human DNA and interrupt regular cellular functions, causing cell mutations, carcinogenesis, and apoptosis (cell death). Heavy metal toxicity affects nearly every system in the human body and often occurs with no distinctive symptoms. It can damage the central nervous system, kidneys, the reproductive system and, at higher levels, can cause coma, convulsions, and even death. Many heavy metals, such as lead and mercury, are neurotoxins, which means they readily cross over the blood–brain barrier and affect the development and growth of brain neurons, so even at low levels, they are associated with reduced brain development, lower intelligence, and learning disabilities. They also have been linked to autism and attention deficit hyperactivity disorder (ADHD). Therefore, it is clear that the repercussions and health risks are potentially significant if humans (especially young children) have a long-term exposure to heavy metals (13).

FDA Mission

The mission of the U.S. FDA is to maintain a safe food supply by monitoring food and related products for both toxic and nutritional elements. The FDA collects and analyzes food and other materials from commercial channels of trade to determine whether those materials are in compliance with applicable regulations. The analytical data gathered through these monitoring activities are also used for evaluating the extent and significance of these analytes in the food supply. FDA laboratories perform these sample analyses using sound analytical practices and methodology, which are documented in the Elemental Analysis Manual for Food and Related Products (EAM). This resource serves as a reference for analysts at the FDA and around the world, providing not only general analytical information but also detailed instrumental methods and sample preparation procedures used for measuring elemental contaminants, including techniques such as inductively coupled plasma–mass spectrometry (ICP-MS), inductively coupled plasma–optical emission spectrometry (ICP-OES), and atomic absorption (AA) for determining arsenic, cadmium, chromium, lead, mercury, and other elements in food using microwave assisted digestion (14). In addition, the manual has a comprehensive list of typical elemental concentrations found in common food materials around the world, including the United States, Canada, Europe, Asia, and Australia. However, it doesn’t address regulatory considerations or set maximum limits because the data are taken from many reference sources around the globe where regional growing, environmental conditions, and industrial influences are very different. Let’s take a closer look at some of those external influences that can impact the quality of the food source.

External Influences

The problem of contaminated food supply has been compounded over the past few decades by the fact that anthropogenic (human) industrial activities, including metal or coal mining, metal refining, power generation, petroleum or petrochemical refineries, lead paint, leaded gasoline, use of lead-based water pipes, and other industrial processes, not to mention natural events such as weathering of rocks and volcanic activity, have seriously compromised the environment and polluted the soil with abnormally high levels of arsenic, lead, cadmium, mercury, and other heavy metals. This makes the selection of farmland to grow these crops and, in particular, optimizing the soil chemistry to minimize the absorption of these heavy metals critically important. However, it should also be pointed out that using certain fertilizers, nutrients, and pesticides can compound the problem. For example, many low-grade phosphate-based fertilizers, as well as natural fertilizers from animal waste and human sewage treatment plants, can have high levels of heavy metals, whereas many pesticides contain lead arsenate and other heavy metals (6). Moreover, added minerals, vitamins, and other chemical additives used in food production need to be scrutinized to ensure they do not further contaminate the consumer products.

Water Quality

In addition, copious amounts of water used in the food industry, in the irrigation of crops, preparation of fertilizers, equipment sanitation, processing operations, and food ingredients and recipes, can all have an impact on the level of heavy metals in the final food products. For this reason, it is critically important that the water used for food manufacturing be tested on a regular basis. This is an important point to make because we take water for granted, and when we turn the spigot on at home, we expect to get clean, uncontaminated water. Take lead for example. The FDA maximum limit for lead in bottled water is 5 ppb as shown in Tables I and II. However, the EPA maximum contaminant limit (MCL) for lead in tap water is 15 ppb, with a recently approved trigger point of 10 ppb for vulnerable communities known as the EPA Lead and Copper Rule Revisions (15). So it is worth explaining why these levels are different. Lead pipes and service lines are still used in many older cities in the United States to carry water from its source via a treatment plant into consumers’ homes. If the chemistry of the drinking water is not well understood, it can dissolve lead from the pipes and pollute the water, unless the chemical composition is optimized. This is what happened in Flint, Michigan, in 2014, where public health officials and water authority personnel failed to take remedial action when they replaced water from Lake Huron with the Flint River as the source of drinking water to cut costs, which resulted in corrosion of the lead pipes and a lead-contaminated drinking water supply. When all the data were evaluated at the height of the crisis in 2015, lead levels in the drinking water were on average a few hundred ppb higher than normal with over half of the homes exceeding 1000 ppb and some in excess of 10,000 ppb (16). As a comparison, the EPA regulated maximum contaminated limit (MCL) for lead in drinking water has recently been reduced to 10 ppb (trigger level) for vulnerable communities from the normal action level of 15 ppb, as defined in the list of primary contaminants in the Safe Drinking Water Act (SDWA). However, this is the specification at the water treatment plant, which could be higher if it is being pumped through lead service lines. To deal with this issue, the EPA mandates that local water authorities test the water in people’s homes every three years. If more than 10% of the homes (or businesses and factories) show levels above the action or trigger level, they will take remedial action depending on the location and the severity of the problem (17,18).

Manufacturing

Therefore, it is clear that food manufacturers need to have better control over their entire manufacturing processes to ensure it is not compounding the problem. They should take a serious look at the way the pharmaceutical industry did it in the later 1990s when after more than 100 years of basically ignoring the problem by just carrying out a semi quantitative, colorimetric test for Pb, it was mandated to clean up its act and monitor up to 24 elemental impurities in drug products and substances described in USP Chapter 232/233 (19,20) and ICH Q3D Guidelines (21). They did this by adopting a risk assessment approach and classified each of the 24 elemental impurities into four different categories, based on their likelihood of their being present at different stages of the manufacturing process. This meant that everything, including raw materials, drug substances (APIs), excipients, and water quality, together with manufacturing equipment, packaging, and delivery systems, had to be thoroughly characterized to ensure the maximum permitted daily exposure (PDE) levels were met in the final drug products. Water is often the source of an impurity when troubleshooting a problem because it is used in such vast quantities. For that reason, it is critically important to monitor the purity of the water supply on a regular basis, as exemplified in Figure 1, which is the classic fishbone diagram that the pharmaceutical industry uses as a framework to find out the root cause of a problem. In this case, the diagram is used to assess the risk of an elemental impurity occurring at any stage throughout the entire manufacturing process (22).

The food industry is nowhere near this level of knowledge of its manufacturing processes as the pharmaceutical industry at the moment, but it will need to get its act together very quickly if it is going meet the ambitious goals of the 2021 Baby Food Safety Act. Moreover, the Act will be asking the FDA to regulate the food industry to maximum heavy metals limits that are an order of magnitude lower than previously required. To do this, manufacturers have to gain a better understanding of the sources of elemental contaminants throughout the entire food production process.

Final Thoughts

The next two years are going to test the relationship between the FDA, baby food manufacturers, and the congressional subcommittee. I’m not sure there are going to be any clear winners, but hopefully at the end of the day, the goal is to have safer baby foods for our children to consume. When the fundamental basis for ensuring the safety of processed baby foods is to grow safe vegetable crops, grain, and cereals, it becomes paramount that manufacturers take all the necessary precautions to minimize levels of heavy metals in foods. Unfortunately, experience tells us that this is never going to be zero. We only have look at studies in the open literature to know that on a practical level this is not possible and that the FDA struggles to ensure food products are low in heavy metal contaminants. This was supported by Atkins and coworkers in a study published in 2018 that measured lead in different types of natural and processed food products including chocolate, cinnamon, hot sauce, canned tuna, indigestion tablets and table salt. They used microwave digestion to get the samples into a solution followed by analysis using ICP-MS and found the samples contained lead at 2–3 orders of magnitude higher than the FDA-regulated level of 2 ppb for bottled water and even significantly higher levels than the 100 ppb for lead in candy (23). The same researchers also did a comprehensive investigation into pet foods in 2009 and then again in 2019 using ICP-MS and found very high levels of a number of different heavy metals, including arsenic, lead, cadmium, nickel, and uranium in many cat and dog foods found on supermarket shelves (24). However, of greater concern for pet owners was that there wasn’t any significant improvement in many of the heavy metals over the 10 years between the two studies, despite the passing of the Food Safety Modernization Act (FSMA) in 2011, which overhauled regulations regarding food production and gave the FDA more authority to oversee and enforce supply chains, including in animal and pet foods. As a result, you would think there would be a vast improvement in the heavy metal contaminant levels in pet food between the two studies. Unfortunately, this doesn’t appear to be the case.

Let me leave you with a final thought, which is based on a Consumer Reports study on heavy metals in baby foods back in 2018, three years before the congressional report (25). Particularly, I reference a letter sent by Consumer Reports senior management to the head of the FDA that concluded, “We also recognize that the FDA has no specific limits in place to restrict contaminants in the vast majority of children’s food. With the agency’s own data and the work of Consumer Reports and other public interest groups in mind, it is critically important for the FDA to take the additional steps to protect the public and assist parents nationwide” (26). They then listed a set of action items to be implemented by the end of 2018 which were very similar to what the congressional report recommended earlier this year. Here we are three years later with very little progress, and it remains to be seen whether baby food manufacturers and the FDA can ever be on the same page. Only time will tell.

References

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