A substance that leached out of cereal packaging and sickened consumers, spurring Kellogg's recall of 28 million boxes of Froot Loops, Apple Jacks and other popular children's cereals, has been identified as a petroleum-based compound that appears to be a breakdown product of chemicals used in the cereal box liners.
This compound, methylnaphthalene (methyl-NAP-tha-lene), has been the subject of major, on-going government and oil industry testing and information-gathering initiatives to identify potential safety issues and fill basic data gaps, according to an Environmental Working Group (EWG) analysis of the scientific literature. Kellogg's has not publicly identified the chemical but provided the information to EWG in response to our inquiries.
Two weeks ago (June 25, 2010), Kellogg's recalled 28 million boxes of Corn Pops, Honey Smacks, Froot Loops and Apple Jacks after customers complained of what the cereal maker called an "off-taste and smell" that caused "nausea and diarrhea" in some people.
In a posting on its website that day, Kellogg’s said "...do not eat any more of this product since it doesn't meet our quality standards" but added that the reactions were not caused by "any harmful material found in the food."
The company told The Wall Street Journal that the recall was prompted by complaints from 20 concerned customers, including five who became nauseous or vomited after smelling or eating the cereal (Brat and Becker 2010).
The Kellogg’s statement said testing found "slightly elevated levels" of a food packaging "substance" in the cereal box liners and that a subsequent health risk assessment showed that "sensitive" customers could expect reactions. The web posting did not identify the substance causing the problem, but it offered consumers a number to call if they had questions or if they "would like a replacement coupon."
An EWG researcher called Kellogg’s 1-800 number to learn more. Company representatives said initially that Kellogg’s did not yet know what chemical had caused the problems, but a company nurse called back the next day with an answer: Kellogg’s chemists had determined that the "off-taste and smell" was caused by methylnaphthalene, which had leached into the cereal from the package liner.
The Kellogg’s nurse, who did not give her name, also said that the U.S. Food and Drug Administration classifies the chemical as "Generally Recognized As Safe," or GRAS. EWG, however, could not find the compound on FDA’s GRAS list online. (FDA 2010a).
Methylnaphthalene, which has two forms, is a component of crude oil and coal tar and may also be formed "as a pyrolytic byproduct from the combustion of tobacco, wood, petroleum-based fuels and coal" (EPA 2003). The petroleum-based compound is produced in enormous quantities in the United States, and health agencies know very little about its safety, EWG research shows.
According to the latest Environmental Protection Agency (EPA) records, chemical companies have been producing the chemical since at least 1986 in amounts between 1 million and 10 million pounds per year (EPA 2008). Numerous health agencies, meanwhile, are still seeking basic safety data on the compound.
- In 1998, EPA identified the compound as a high production volume (HPV) chemical that lacked basic safety data in the public literature. The agency sought a corporate sponsor to submit such data to EPA’s "HPV Challenge" program. In 1999, a consortium of large petrochemical interests volunteered, including BP, Chevron, Condea Vista, Exxon, Fina Oil, Koch, Marathon Ashland, Mobil Oil, PDV Midwest Refining, Phillips Petroleum, Shell and Sunoco. Eleven years later, however, EPA’s HPV Challenge program website shows no data whatsoever submitted by these companies (EPA 2010).
- In a related action, EPA’s Office of Pollution Prevention and Toxic Substances has promised to evaluate methylnaphthalene in an international effort to assess the safety of high production chemicals. Industry-provided data form the backbone of such evaluations. The international OECD (Organisation for Economic Co-operation and Development) website says that the US government is currently in its initial step of "Information gathering & Data Review" (OECD 2010a). As part of the same process the Korean government has determined that 2-methylnaphthalene has "possible toxicity to human health" (OECD 2010b).
- The FDA lists methylnaphthalene as a compound that is added to food and notes that it is seeking safety data on the chemical: "Fully up-to-date toxicology information has been sought," the agency website reports (FDA 2010b).
- The Agency for Toxic Substances and Disease Registry (ATSDR) reviewed the safety of methylnaphthalenes in 2005 (ATSDR 2005). The agency reported that: "You are not likely to be exposed to [methylnaphthalene] by eating foods or drinking beverages," though you could be exposed "if you live near a hazardous waste site..." The agency noted that people can be exposed when using or making moth repellents, coal tar products, dyes or inks but did not mention breakfast cereal. ATSDR found that "There are no studies in humans or animals indicating whether or not children are more susceptible to health effects from [methylnaphthalene]."
What Kellogg’s said in its public statement:
"These packages are being recalled because we identified a substance in the package liner that can produce an uncharacteristic waxy-like off-taste and smell. The off-tastes and smells are caused by a slightly elevated level of a substance commonly present at very low levels in the waxy resins used to make packaging materials that are approved by the FDA. These resins are also commonly used to coat foods such as cheese, raw fruits and vegetables such as cucumbers. We did not find any substances that are not commonly used in packaging materials." (Kellogg’s 2010)
"We completed a thorough health-risk assessment with external experts in medicine, toxicology, public health, chemistry, and food safety. The experts agree that some consumers are particularly sensitive to these uncharacteristic off-tastes and smells and may have temporary symptoms, like nausea and diarrhea, which should subside shortly. These symptoms are a result of the off-taste and odor in the food; they are not caused by any harmful material in the food.
You should not eat the recalled product because it does not meet quality standards. If you have concerns about your health, you should consult their health care provider." (Kellogg’s 2010)
What is known about methylnaphthalene toxicity?
The little data publicly available on the toxicity of methylnaphthalene was summarized in a 2005 government review (ATSDR 2005) and in a few subsequent studies published in the peer-reviewed literature.
The chemical is known to be commonly detected in air pollutants from cigarette smoke, diesel and gasoline engine exhaust, wood smoke, tar and asphalt (ATSDR 2005).
Animal studies show that methylnaphthalene causes lung damage when exposure occurs via inhalation, ingestion and skin contact. Mice given feed containing 0.075 percent or 0.15 percent of 1- or 2-methylnaphthalene for 81 weeks had lung damage known as "pulmonary alveolar proteinosis," marked by abnormal lipids, proteins and fluid in the lung (ATSDR 2005, citing Murata 1993, 1997). Applying a mixture of 1- and 2-methylnaphthalene to the skin resulted in similar lung injury to mice (Murata 1992). In people, this lung disease is unusual and is typically caused by inhaling particulates (Lin 2009). Other types of acute lung damage have been reported, including to the epithelial and Clara cells and to the nasal epithelium (Lin 2009)
In 2005, the Agency for Toxic Substances and Disease Registry concluded: "The available data on the methylnaphthalenes appear inadequate to determine their carcinogenicity potential in humans" (ATSDR 2005).
The FDA and EPA have not set safe exposure levels. ATSDR has set minimal risk levels of 0.04 and 0.07 milligram per kilogram bodyweight per day (mg/kg-d) for long-term exposure to 1- and 2-methylnaphthalene, respectively (ATSDR 2005). ATSDR also concluded that consumers are likely not exposed to methylnaphthalene via food, a statement that warrants reexamination given the chemical’s detection in Kellogg’s food packaging (ATSDR 2005).
Methylnapthalene contamination in cereal raises safety questions. The chemical is structurally similar to naphthalene, which was the primary component in mothballs until those products were reformulated due to toxicity concerns. Naphthalene and methylnapthalene share the same toxicity to lung cells. Naphthalene is also toxic to red blood cells, causing anemia, fatigue, nausea, vomiting and diarrhea (ATSDR 2005). The methylated form of the mothball chemical has not been fully assessed for toxicity to blood cells, a critical data gap when it comes to evaluating the potential effects of food contamination. The National Library of Medicine’s Hazardous Substances Data Bank lists these symptoms as a concern for workers exposed to methylnapthalene (NLM 2010).
The San Antonio Budget Grocery Examiner reported that consumers affected by the contaminated cereal typically experienced nausea and/or vomiting within 15 minutes of ingesting the cereal (King 2010). Kellogg’s attributed these effects to some individuals’ increased susceptibility to the chemical’s smell and odor (Kellogg’s 2010).
Both the company and the FDA have an obligation to follow up. It is vital that we know how the chemical made its way into the cereal boxes and what is known about the safety of this compound for children in particular, since the recalled cereals are especially popular among them.
Gaps in the food safety program
Most importantly, this episode casts further doubt upon the ability of the FDA to evaluate and assure the safety of food packaging. Methylnapthalene gives off a strong taste and odor at quite low levels. People can discern its presence at concentrations as low as 7.5 to 10 parts per billion in air and water. In the case of Kellogg’s cereals, it affected the smell and taste of the products. Thousands of other food additives, however, would not be so obvious to consumers.
Food packaging is already under scrutiny because of recent concerns over the synthetic estrogen bisphenol A (BPA) leaching from the coatings on metal food cans and jar lids into baby food, formula and other canned foods. The FDA admits that the current regulatory structure "limits [its] the oversight and flexibility" in responding to the issue of BPA in food packaging (FDA 2010c). The agency does not know how many foods contain trace levels of BPA, nor can it determine who is using petroleum waxes in packaging. It would take a lengthy rulemaking process for the Agency to request the relevant use and safety data. As a result, FDA is seeking new authority to evaluate and assure the safety of BPA in food packaging.
The discovery of contaminated cereal packaging raises serious questions about FDA’s authority to investigate and regulate all chemicals that make their way from cardboard boxes, plastic bags, metal cans and coated papers into our breakfasts and our bodies.
In light of the lack of information on the safety of this chemical, EWG calls on Kellogg’s to disclose the exact chemical composition and concentration of methylnaphthalene and any other compounds that leach from the cereal packaging, and to make public its safety data and its assessment of human health risks to those who were exposed. We call on FDA to do the same.
The FDA should independently assess and make public its evaluation of the potential impacts of this chemical and ensure that food producers take all necessary steps to ensure that packaging materials do not continue to sicken consumers.
Ultimately, food safety laws must be strengthened to ensure that the FDA sets stringent standards for packaging chemicals and has the authority to enforce them. As a start, all chemicals in food packaging should comply with the Food Contact Notification Program FDA implemented in 2000. Furthermore, companies should be required to test for chemicals leaching from their packaging, report the results to FDA and make the data available to the public.