http://findarticles.com/p/articles/mi_m1370/is_3_36/ai_87105434"Pentobarbital is an anesthetizing drug used for dogs and other animals, such as horses and cattle. Because it is also widely used for humane euthanasia of dogs, cats and other animals, the most likely way that pentobarbital could get into dog food would be in rendered animal products. Rendered products come from a process that converts animal tissues to feed ingredients.
"During the 1990s, the FDA's Center for Veterinary Medicine (CVM) received reports from veterinarians that pentobarbital seemed to be losing its effectiveness for anesthesia in dogs. Based on these reports, the center decided to investigate the theory that the dogs were exposed to pentobarbital through dog food, and that this exposure was making them less responsive to pentobarbital when it was used as a drug.
"CVM developed and used a sophisticated process to detect and quantify minute amounts of pentobarbital in dog food. Upon finding pentobarbital residues in some samples of dry dog food, CVM scientists conducted further tests that led them to conclude that dogs eating dry dog food are unlikely to have any adverse health effects from the low levels of pentobarbital found in the dog food samples tested."
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"After finding that the low levels of pentobarbital that dogs might receive through food are unlikely to cause them any adverse health effects, FDA officials did not think that further research into the issue was necessary. CVM officials say they plan to publish the study findings in peer-reviewed scientific journals.
"CVM's studies and a summary report of the results are available at www.fda.gov/cvm/efoi/efoi.html."
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11599994&dopt=Abstract"Center for Veterinary Medicine, U.S. Food and Drug Administration, Laurel, Maryland 20708, USA. dheller@cvm.fda.gov
"A procedure has been developed and validated for measuring the concentration of pentobarbital residues in dry, extruded animal feed in the range of 3-200 ng/g (ppb) with an estimated limit of quantitation of 2 ppb. The method was developed for surveillance purposes: to measure the concentration of euthanizing agent which might be present in feeds incorporating rendered products which themselves might include some fraction of euthanized animals."
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