|O'KEEFE, MARGARET - Food Safety Inspection Service (FSIS)|
|BASU, PAT - Food Safety Inspection Service (FSIS)|
|MUNIZ-ORTIZ, JORGE - Food Safety Inspection Service (FSIS)|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/6/2015
Publication Date: 8/23/2015
Citation: Lupton, S.J., O'Keefe, M., Basu, P., Muniz-Ortiz, J. 2015. Dioxins, dioxin-like compounds, and PBDEs in the U.S. domestic meat supply: trends and levels 2003 to 2013 [abstract]. 35th International Symposium on Halogenated Persistent Organic Pollutants [Dioxin 2015]. August 23-28, 2015. Sao Paulo, Brazil. Paper No. PAP019465.
Interpretive Summary: Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) are environmental contaminants classified as persistent organic pollutants (POPs) by the Stockholm Convention. PCDD/Fs are waste products from industrial applications and form during incineration processes. PCBs and PBDEs, however, were man-made and introduced into different industrial and consumer products. POPs have the ability to accumulate in the fat rich tissue of animals and humans. As a result, consumers are exposed to these compounds through meat products regulated by the United States Department of Agriculture-Food Safety and Inspection Service. The FSIS and Agricultural Research Service have conducted surveys every 5 years of fat samples from beef, pork, chicken, and turkey directly from animal processing facilities over the last two decades. Surveys were completed to determine background levels of PCDD/Fs, PCBs, and PBDEs and temporal trends of mean and median values observed in the surveys. Overall, levels of these contaminants have decreased over the last 20 years. Results from these surveys are also used to investigate unusually high levels found to determine possible contamination sources (i.e. feed, treated wood, incineration ash). Also, knowing current background levels in these production classes can help with trade disputes if necessary.
Technical Abstract: In the mid-1990s, 2002-2003, 2007-2008, and again in 2012-2013 the U.S. Department of Agriculture (USDA) conducted statistical surveys for dioxin and dioxin-like compound (PCDDs, PCDFs, and PCBs) residues in domestic meat and poultry. The surveys were conducted to determine background levels of dioxins and dioxin-like compounds in domestic beef, pork, and poultry, as well as to track temporal trends, and uncover sources of dioxins to the food supply by investigating any unusual findings. Additionally, these data sets being statistically based are able to be used to estimate human exposure to dioxins, dioxin-like compounds, and PBDEs based on consumption information of domestic meat and poultry. The 2012-2013 dioxin survey was conducted using the same methodology from the previous surveys completed in 2002-2003 and 2007-2008. Briefly, federal inspectors collected adipose tissue samples from U.S. slaughtering facilities on a monthly basis from October 2012 through September 2013. Sampling framework represented the major categories of domestic meat and poultry production in the U.S., where all operating facilities were eligible for sampling. The survey consisted of a total of 514 samples: 139 beef (heifers and steers), 137 pork (gilts and barrows), 153 young chickens, and 85 young turkeys, with each class weighted according to its production volume. Analyses were completed on 5 g of homogenized adipose tissue samples according to EPA Method 1613 for PCDD/Fs (modified to include the no-PCBs) and EPA Method 1614 for PBDEs. A method blank was analyzed with each set of 15 survey samples and used for blank subtraction as was done in the previous surveys. Limits of detection (LOD) were defined by the standard deviation of either method blanks or low level spikes (LOD = 2xSD). TEQs were calculated from the current and previous survey data using the WHO 2005 TEFs and reporting non-detects as zero or LOD/2. All values are expressed in pg/g lipid for PCDD/F/PCBs and ng/g lipid for PBDEs. From the 2007-2008 survey to the current survey there is a slight increase in the beef mean PCDD/F TEQs (+1.8%), however all other slaughter classes decreased, market hogs are -28%, young chickens are -8.3% and young turkeys are down -28%. Mean TEQs for the no-PCBS have also decreased from 2007-2008 to 2012-2013 for all classes except the market hogs. The differences of the mean SPBDEs between the 2007-2008 and 2012-2013 surveys were +27% for beef, -31% for market hogs, -77% for young chickens, and -57% for young turkeys. A comparison of the survey data shows that for all slaughter classes median TEQs appear to have declined over the past two decades, but this decline may be slowing down or leveling off in at least one slaughter class (beef). During each survey, outlier values have been identified that do not reflect the general population. In all cases, these samples were investigated to determine contamination sources. Most investigations revealed sources (old fence posts and utility poles) that could easily be corrected. Present survey investigations are currently concluding.