High levels of polybrominated diphenyl ether (PBDE) flame retardants found in a butter sample were most likely caused by tainted packaging, said scientists as they called for stricter regulatory scrutiny of the chemical in the food chain.
The international research team urged US authorities to introduce systematic testing for the substance after discovering an elevated concentration of deca-BDE, in one of ten butter samples purchased from five grocery stores in the US city of Dallas. This is the first-known incidence of PBDE contamination in US butter, said the study, which is to appear in the Environmental Health Perspectives journal, published by the National Institute of Environmental Health Sciences (NIEHS).
This PBDE compound, widely used in electronics and textiles, wire and cable insulation, and automobile and airplane components, will be phased out by 2014 because of its toxicity to humans and animals.
The problem was revealed during a routine investigation intended to improve estimates of the amount of PBDEs and other persistent organic pollutants (POP) inadvertently consumed in food.
Packaging likely source
The group, led by Arnold Schecter of the University of Texas School of Public Health, found PBDE levels in the contaminated butter were more than 135 times higher than the average of the other nine samples; levels of BDE-209, the main component of deca-BDE, were more than 900 times higher.
Further investigation revealed the butter’s paper wrapper had PBDE levels more than 16 times greater than levels in the butter itself. While the source could not be confirmed, the research concluded the contamination “is most likely from the paper wrapper contamination with octa- and deca BDE, either from electronic devices in the butter processing plant or from the paper prior to delivery”.
The food processor involved investigated the incident but to date hasn’t shared its findings, said the researchers.
The study acknowledged that the sample size was small but added that it could serve to alert authorities and food processors that “relatively high levels of food contamination with emerging POPs sometimes occurs”.
“While an exact source is not yet clear, we suspect that high levels of contamination can occur during food processing and packaging,” said the researchers.
The authors highlighted the need for a regulatory programme that samples American food for persistent organic pollutants such as PBDEs because chemicals remain in the environment even after their manufacture has ceased.
The US Food and Drug Administration (FDA) does not currently have tolerances, guidance levels, or action levels established for PBDEs. Spot checks by regulators could help characterise the nature and extent of potential health hazards, said the group.
“By investigating the circumstances in which chemical contamination of US food occurs, it will be possible to determine when and where screening for POPs contamination of food is most appropriate and will also help reduce incidence of contaminated food sold to the public,” said the research.
Contamination of U.S. Butter with PBDEs from Wrapping Paper by Arnold Schecter, Sarah Smith, Justin Colacino, Noor Malik, Matthias Opel, Olaf Paepke, and Linda Birnbaum
Source: Environmental Health Perspectives
doi: 10.1289/ehp.1002604 (available at http://dx.doi.org/)