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Preliminary National Survey of Dioxin-like Compounds in Animal Fats, Animal Meals, Oilseed Deodorizer Distillates, and Molasses
May 22, 2000 Director, Office of Surveillance and Compliance (HFV-200) Preliminary National Survey of Dioxin-like Compounds in Animal Fats, Animal Meals, Oilseed FDA District Directors: NYK, BLT, CHI, CIN, DET, MIN, ATL, FLA, NOL, DAL, DEN, KAN, Info: All remaining FDA District Directors Objectives To determine background levels of dioxin-like compounds in fatty and other feed ingredients commonly used in animal feeds. The data from the molasses samples may provide insight into the relative importance of air deposition, soil contamination, or fire on the dietary exposure of animals to dioxin-like compounds. Dioxins are a family of about 30 lipophilic compounds (polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls), often called congeners, that accumulate in the fat of humans and animals. They appear to act by binding to the Ah (aromatic hydrocarbon) receptor and to produce a broad range of adverse effects including, but not limited to, enhanced tumorigenicity, enzyme induction, immune suppression and a wasting syndrome. The most toxic congeners are 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PeCDD). Sample results are often expressed in parts per trillion (ppt) of toxicity equivalents, or TEQ. The TEQ concentration of individual congeners is calculated as the analytical concentration of that congener times its toxicity equivalency factor, or TEF. The TEF for TCDD and PeCDD has been set at 1 since they are the most toxic congeners. The TEFs for the other congeners are less than 1 and are based upon their interaction with the Ah receptor compared to TCDD/PeCDD. The sum of the TEQ concentrations for the individual congeners is the TEQ concentration for the mixture. Since the TEQ concentration of a mixture of dioxin congeners is estimated to be equivalent to a concentration of just TCDD or just PeCDD, this provides consistency in addressing dioxin contaminations of various mixtures. In 1994, the US Environmental Protection Agency (EPA) issued a draft risk assessment on dioxins and it indicated that >90% of dioxin exposure in the United States came from the diet, primarily from consumption of animal products. The EPA and United States Department of Agriculture (USDA) then conducted joint national surveys of dioxins in beef, pork and poultry to obtain background levels in these products and to assist in revising the risk assessment. In 1997 following the EPA/USDA poultry survey, FDA/EPA/USDA/Center for Disease Control traced the source of elevated dioxins in broilers to ball clay, an anti-caking agent used in feeds. This investigation traced the ball clay to a mine in Mississippi. Although the cause of the dioxin contamination in the ball clay has not been definitively ascertained, most believe it is of natural origin. After learning that other ball clay mines in Kentucky and Tennessee also contained elevated dioxin levels, the FDA issued a letter, dated 10/7/97, to producers or users of clay products in animal feeds asking that they cease using ball clay in any animal feed or feed ingredient. Center for Veterinary Medicine (CVM) subsequently issued an assignment to the Field to collect anti-caking products used in animal feeds and oilseed meals. The samples from this survey were analyzed by the EPA Environmental Chemistry Laboratory and the FDA Arkansas Regional Laboratory. Nine of 15 samples contained dioxins at low levels, ranging from 0.4 to 22.5 ppt TEQ, with the penta congener (PeCDD) contributing the most to the sample TEQ. For comparison, the ball clay from the 1997 investigation contained dioxin levels over 1000 ppt TEQ and TCDD was the primary congener contributing to the sample TEQ. In a recently completed study of lactating dairy cows at one farm, EPA/USDA found that dioxin exposure was about equally divided between the fodder (hay, grass, silage, etc.) and the non-fodder (animal and vegetable byproducts, vitamin/mineral supplements, anti-caking agents, etc.) components of the diet. This preliminary finding was somewhat unexpected as many scientists believe that dioxin-like compounds originate primarily as a waste byproduct of chlorinated chemical manufacturing, bleaching and combustion, and that air to leaf deposition on fodder, and subsequent consumption of that fodder by the animal, is the predominant route of exposure. The evidence gathered thus far suggests the primary source of dioxin contamination in food animals is from their diet and that the non-fodder components of the diet deserve additional scrutiny. Since dioxins are predominantly found in fats, the FDA and EPA believe most of the samples collected in this preliminary survey should be fatty in nature and come from commonly used ingredients of animal and plant origin that are likely to contain relatively high levels of dioxins. Thus, beef fat, pork fat, fat and meat & bone meal from mixed animal species, poultry byproduct meal, various fish meals, and deodorizer distillates from five commonly grown oilseeds were selected. In addition, cane, beet and starch molasses were selected because they are common feed ingredients, not fatty, and may provide some insight into the relative importance of air deposition, soil contamination (on beets), or fire (in cane harvesting) on the dietary exposure of animals to dioxins. The Ingredients and Geographic Region chart (Attachment D) developed by Versar (EPA contractor) forms the basis for the feed ingredients and states selected for this assignment. Characterizing the selected feed ingredients: Deodorizer distillates - A byproduct of the final step in the commercial refining of vegetable oils (corn, soybean, peanut, cottonseed, canola). In the 1980’s, FDA proposed a ban on the use of deodorizer distillates in animal feed. These ingredients will likely contain toxic organic contaminants such as halogenated industrial contaminants (PCBs) and halogenated pesticides (aldrin, dieldrin, etc.). These contaminants are removed from the crude oil during the deodorizing (distillation) steps of refining and are concentrated in the deodorizer distillate fraction. The distillates may be found at oilseed processors that produce corn, soybean, peanut, cottonseed, and canola oils, meals and other byproducts. Fat from beef or pork - Sample at integrated animal renderers that are associated with a slaughter facility and that only process beef, that only process pork, or that have segregated operations for beef or pork. Do not sample from operations that combine beef or pork byproducts with recycled restaurant grease or with byproducts of other animal species. Fat from mixed animal species/other sources - Sample at independent animal renderers (i.e. those not associated with a slaughter facility) whose products may include fat from mixed animal species, road kill, and/or recycled restaurant grease. Meat & bone meal from mixed animal species - Sample, if possible, at the same sites where "Fat from mixed animal species" were obtained. The product is a protein meal which may be called meat meal, meat & bone meal, meat tankage, cracklings, or dried meat scraps. Do not include bone meal by itself as a sample for this assignment. Poultry byproduct meal - These samples are meal from poultry byproducts that may include blood or feathers, but should not be exclusively a blood or feather meal. Remember, it is the fat portion of this meal product which will likely contain most of the dioxin-like compounds. Fish meal Catfish and anchovy - Use of catfish meal as a feed source appears to be limited largely to pet food. The Kansas City District should try to collect a sample of anchovy meal that is of Peruvian or Chilean origin.
Molasses (cane, beet, starch) - It is used in small quantities in feed to control dust and improve palatability. Molasses may be a possible source of dioxin contamination caused by air deposition, by soil contamination (on beets), and by fire (during cane harvesting). This is a nationwide survey and the districts involved will be collecting from one to five samples each. The Field will collect a total of 48 samples, three for each of 16 sample types. The feed ingredients selected for sampling are equally divided between animal and plant origin. Our intent is to obtain samples close to the feed source of the food producing animals so that samples reflect animal exposure to dioxins. We recognize the difficulties in sampling at farms. Other facilities, such as feed mills, may be used for sampling; however the feed ingredients there may have already been mixed, combined with other ingredients or otherwise contaminated. Therefore the primary sites selected for sampling include animal renderers and fish meal, oilseed and molasses processors. See Attachment A for the specific products to be sampled and their appropriate product codes. A sampling chart (Attachment B) identifies the sample types, the selected districts where the particular samples should be collected and the number and type of samples scheduled for collection by district. Each of 15 lists of firms (Attachment C) identifies the type of feed ingredient(s) produced, the related firm locations by state, and, if possible, by address, telephone and CFN. Before beginning this assignment, each district should choose a person as a District Contact. This person will coordinate and communicate with the FDA investigator(s), the EPA laboratory, Versar (the EPA contractor), and CVM regarding sampling and sample transport and tracking. Each district will submit the name and telephone number of the District Contact to Patsy Gardner, the CVM Coordinator for this project, who will inform Ann Cyrus at Versar and Joe Ferrario at the EPA lab. After receiving the names, CVM will hold a teleconference with District Contacts, appropriate district personnel, EPA Environmental Chemistry Laboratory, FDA Arkansas Regional Laboratory, and Versar to get acquainted, resolve any problems and answer questions. All samples collected are official samples and should be collected within 45 days after the group teleconference using the sampling package provided. The assignments for sampling will be sent to each district via the Field Accomplishments and Compliance Tracking System (FACTS). Also, the assignment with full instructions and Attachments will be sent to the districts, the EPA lab and Versar by paper copy. Versar will assemble a total of 72 sampling packages. Versar will provide each District Contact with sampling packages equal to the total number of sample collections each district is assigned (Attachment B). Versar will also provide each District Contact with one additional sampling package in case of breakage or loss. The sampling package will contain the following items:
There will be four general category types of samples collected--fats, meals, distillates and molasses. To minimize the potential for contamination, use only the tools in the kit or, if possible, obtain samples without tools (e.g., sampling fats from a spigot at a vat). If possible, avoid contact between the gloves and the sample or the inside of the sample jar. We suggest the District Contact review their particular sampling assignment (Attachments B and C) soon after receipt, making sure that the sample types selected for your district are available at the identified firms. The District Contact will call prospective firms before the investigator visits and determine that each firm produces or uses the ingredient identified in Attachment B. The District Contact will give the investigators the sampling packages and a list of available firm(s), by sample type, to visit. Although sampling will probably occur at renderers and processors (primary sites), some firms identified may not produce the ingredient(s), the product may be unavailable due to seasonality, or the firm may be too distant. For any of these reasons, the District Contact may want to use secondary sites (feed mills or distributors) to obtain samples. If the sample is to be collected at sites other than the ingredient manufacturer, it is important that the ingredient not be combined with any other ingredient(s) when collected. At these secondary collection sites, make every effort to obtain and record on the c/r the name and address of the original ingredient manufacturer. We recognize it may be difficult to obtain, but we ask that the investigator make every effort to determine where each collected feed ingredient originated, i.e., in what state(s)/country was the product grown/raised or harvested near. The sampling chart (Attachment B) identifies the number of samples and sample type(s) each district is scheduled to collect. If possible, collect samples of fat from mixed species/other sources and meat & bone meal from mixed animal species at the same firm. These samples should come from independent animal renderers that are not associated with a slaughter facility. Make every effort to identify integrated animal renderers (packer renderer associated with a slaughter facility) when collecting the beef fat or pork fat samples. If no such integrated animal renderers are found, inform the CVM Coordinator. Do not attempt to collect these types of samples at other facilities. To avoid contamination of the sample jar keep the cover open only as long as it takes to insert the sample into the jar. When collecting the sample, the investigator should use the gloves and the wide-mouthed, amber glass jars with teflon-lined covers, all of which will be provided by your District Contact. For liquid samples, fill the sample jar approximately 1/2 (50%) to 2/3 (67%) full of the ingredient. For non-liquid samples, fill the sample jar approximately 4/5 (80%) full of the ingredient. If the investigator collects more than one sample at a firm, remember to label each jar with the correct sample type. Put the jar in a zip-lock bag and use bubble wrap and flexible coolant packs to protect the samples in transit. Maintain samples in the dark and under freezing conditions after collection until shipment to the EPA lab. If a firm wants a sample for their own analysis, provide them with a 702 (b) portion using the second sample jar in the sample package. Collect a copy of the label and shipping receipts, if available. If the investigator has any problems or questions during sampling, call the District Contact or, if necessary, the CVM Coordinator. The District Contact will receive the samples and package each one with a c/r. If the investigator has already packed the sample, make sure it includes the c/r and is wrapped in a flexible coolant pack using suitable packaging for protection. When ready to ship a sample to the lab, the District Contact will call the EPA Sample Custodian (who will inform the EPA lab and its director) and identify the sample and the shipper (Fed Ex, Post Office, UPS, etc.). The District Contacts will keep track of the samples sent to the lab and will try to locate any lost sample. If a sample has been lost or compromised, the District Contact will attempt to have another sample collected. If a sample can’t be collected in the selected district for any reason, the CVM Coordinator will be contacted and another district may be asked to collect the sample. Instructions for District Contacts when shipping samples to the EPA lab (see IOM chapter 4 - Sampling, 454.5, page 161):
Samples will be maintained at a freezing temperature in the dark prior to and after analysis. Samples will be prepared and analyzed using methods and quality assurance/quality control procedures that generally follow those described in EPA’s Method 1613: Tetra- Through Octa- Chlorinated Dioxins and Furans by Isotope Dilution HRGC/HRMS. For the dioxins and furans, details of the methods and a description of the specific changes made to Method 1613 are detailed in the following publication: Determination of 2,3,7,8-Chlorine Substituted Dibenzo-p-dioxins and -furans at the Parts per Trillion Level in United States Beef Fat Using HRGC/HRMS, Analytical Chemistry, Vol 68, No. 4, 1996. For the co-planar PCBs, specific details are described in the following publication: Background Contamination by Coplanar Polychlorinated Biphenyls (PCBs) in Trace Level HRGC/HRMS Analytical Procedures, Chemosphere, Vol. 34, No.11, 1997. Extraction procedures will vary depending on the specific matrix but will generally involve solvent extraction followed by the "clean-up" and analytical procedures described in the methods listed above. Details of the extraction procedures once developed and details of the procedures used to ensure that the glass jars with lids are dioxin free will be incorporated as addendums to the EPA Analytical Quality Assurance Project Plan. When the EPA lab has completed their analyses, they will send the unused portions of the samples to the FDA Arkansas Regional Laboratory (ARL) for storage and disposal. At the discretion of Meredith Grahn, ARL Director, the samples may be analyzed for dioxins by ARL. The feed ingredients in this survey have not been previously sampled for dioxins by CVM. CVM will coordinate a follow-up with the district(s) if elevated levels of dioxins are detected. If you have any question related to regulatory/enforcement activity please contact Judy Gushee, CVM, Division of Compliance. If computer transmission by FACTS is unavailable, the EPA lab and the District Contacts may send documents to Patsy Gardner by mail (address below), e-mail (pgardner@cvm.fda.gov) or fax (301-827-1484).
As CVM Coordinator for this assignment, Patsy Gardner will receive the following information from the District Contacts and the EPA lab:
CVM will send EPA’s analytical data to the collecting districts. The collecting districts will report their work and time under PAC 71003A. The product codes for this assignment are listed in Attachment A. CVM Compliance: Judy Gushee, HFV-236, 301-827-0150, e-mail - jgushee@cvm.fda.gov Linda Tollefson, DVM, MPH PRIORITY: HIGH Estimated completion date for sample collection: August 15, 2000 Attachment A: Product Codes [ html ] [ pdf ]
Attachment C -- REDACTE
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