Location: Animal Metabolism-Agricultural Chemicals Research
Project Number: 3060-32420-002-000-D
Project Type: In-House Appropriated
Start Date: Feb 8, 2016
End Date: Aug 2, 2019
Objective 1: Develop and/or validate rapid screening assays for the detection of environmental chemicals relevant to U.S. food production. Sub-objective 1.A: Development of immunochemically based rapid screening methods for new and emerging persistent organic pollutants. Sub-objective 1.B: Development of immunochemical purification methods for new and emerging persistent organic pollutants. Objective 2: Determine levels and sources of dioxins and related compounds in the domestic food supply. Provide food safety agencies with data to confirm or refute the wholesomeness and competitiveness of beef, pork, chickens, turkeys and/or catfish. Sub-objective 2.A: Conduct a nationally-based survey of PCDD/PCDF/PCB/PBDE levels in the domestic meat supply (beef, pork, chicken, turkey, and/or catfish) by collection of adipose tissues from U.S. slaughter facilities. Sub-objective 2.B: Identify potential production-based or environmental sources of PCDDs/PCDFs/PCBs/PBDEs in food-producing animals. Objective 3: Determine the uptake, metabolism (in vitro or in vivo), distribution, excretion, and fate of environmental contaminants with the goal of developing pharmacokinetic rate and volume constants pertinent to residue depletion, selection of marker compounds, and calculation of withdrawal intervals. Sub-objective 3.A: Characterize the absorption, disposition, metabolism, and excretion (ADME) of POPs in food animals. Sub-objective 3.B: Identify cellular fractions and enzyme classes responsible for the metabolism and putative dehalogenation of POPs. Sub-objective 3.C: Characterize the bioavailability of POPs in animal systems from major exposure routes. Sub-objective 3.D: Determine the fate and transport of POPs through soil during ambient weather conditions. Sub-objective 3.E: Determine the effect of milk processing on POP concentrations in finished products.
Ubiquitous environmental contaminants enter the human meat supply when animals are exposed through surroundings and feeds. These compounds, known as persistent organic pollutants (POPs) satisfy the standards for chemicals of concern in that they are persistent, bioaccumulative, globally transported, and toxic. U.S. and international health organizations recommend continuing to decrease human exposure by lowering levels in foods and the environment. Our research efforts focus on reducing animal and human exposures to these contaminants using three approaches. First, we will develop rapid, inexpensive assays and cleanup tools for isolating and detecting POPs in food products. These assays could result in broad monitoring of the food supply, which currently is not feasible due to the high analysis costs. Second, we will continue to survey the U.S. meat supply (beef, pork, chicken, turkey and/or catfish) for POPs, and will track current levels with trends measured over the last two decades. These data are critical to regulatory agencies for risk assessment, and have revealed POP sources that have contributed to livestock exposures and contamination. Once identified sources of contamination may be eliminated or avoided. Third, we will perform basic research to determine pharmacokinetic parameters for POPs in laboratory and farm animals and will develop potential remediation methods using animal feeding studies. We will use these data to calculate withdrawal intervals, and elucidate strategies to decrease contaminant levels in food animals.