230 likes | 469 Views
What’s going on in a Veterinary Toxicology Laboratory?. Birgit Puschner Veterinary Toxicologist DVM, PhD, Dipl. ABVT bpuschner@ucdavis.edu. Toxicology Laboratory Capabilities. Providing information Diagnosis of intoxications and nutritional imbalances Prevention of intoxications
E N D
What’s going on in a Veterinary Toxicology Laboratory? Birgit Puschner Veterinary Toxicologist DVM, PhD, Dipl. ABVT bpuschner@ucdavis.edu
Toxicology Laboratory Capabilities • Providing information • Diagnosis of intoxications and nutritional imbalances • Prevention of intoxications • Ensuring food safety • Prevention/identification of chemical agroterrorism
Laboratory Set-up • 2 ABVT certified toxicologists • 1 resident/PhD student • 1 Senior analytical chemist (PhD) • 10 analytical chemists (M.S., B.S) • Sample receiving area
Toxicology Testing • 450 to 500 case submissions per month • ~35,000 tests per year • Chain-of-custody • QC/QA in place • Over 80 validated analytical methods • Established turn-around-times • Method development
Toxicology Instrumentation • Triple quadrupole LC-MS/MS (2) • Ion-trap LC-MS/MS (1) • HPLC and GC/MS • ECD, FPD, FID, NPD, UV, and fluorescence detectors • ICP-MS (1) • ICP/AES (1) • AA (1) • Elisa plate reader (2)
Case Discussions • Oleander • Paraquat • Zinc phosphide • Anatoxin-a
Highly toxic Dried and fresh ~7 leaves can kill a horse or cow ~1 leaf can kill a human Oleander
Oleander Method by LC-MS • Serum, urine and tissues • MDL (serum, urine): 1 ppb • MDL (liver): 5 ppb Mass spec identification and quantitation
Oleandrin Oleandrin in Human Blood – 9 ppb
Tests for Plant Toxins • Cardiotoxin screen: oleandrin, gitoxin, GTXs • Strophanthidin • Alkaloids: • coniine, nicotine, anabasine, lupanine • atropine, scopolamine • taxines • senecionine, seneciophylline, retrorsine • Nitrate/nitrite • Cyanide • Gossypol
Paraquat • History: • OR in 2003 and 2004: more than 20 dogs become ill after visiting an off-leash park and a beach area. Most of them died. • Acute onset of vomiting and diarrhea after park or beach visit. • Many dogs were not presented until 2-3 days. • Inappetence and lethargy, renal and respiratory failure • Samples collected for toxicology testing: • Urine, lung, vomitus
Paraquat • Colorimetric, SPE quick test • Development of a new LC/MS methodology
Paraquat LC/MS – Implications • Provides unambiguous identification • Very fast: analysis within 1-2 hours • Low detection limits: • Urine: 50 ppb • Lung: 500 ppb • Quantitation of paraquat in serum or plasma of poisoned animals or humans: • Used to assess the severity of the intoxication • Used as a prognostic indicator
Zinc Phosphide • History: • Puppy presented in critical condition at vet clinic • Owners mentioned “gopher bait” in backyard • Vets and veterinary technicians developed severe headaches, itchy skin and sore throats • Samples collected for toxicology testing: • Stomach contents
Zinc Phosphide • Diagnostic testing: • SPME extraction, followed by GC/MS • Confirmed presence of phosphine • Phosphide-containing gopher baits: • Grain bait, paste, tablets, tracking powder • Concentration from 0.5% to 10% • Minimum lethal dose for most species:12 – 50 mg/kg • Precaution when collecting samples!
Insecticides: Organophosphates (43) Carbamates (11) Organochlorines (22) Pyrethrins (8) Rodenticides: Anticoagulant rodenticides (8) Strychnine Bromethalin Zinc phosphide Others: Avitrol Paraquat Metaldehyde Ethylene glycol Cyanide Drugs: NSAIDs Macrolide endectocides Tests for Pesticides/Household Toxins
Cyanotoxins • History: • 3 dogs developed seizures and died after swimming in the Eel River • Samples collected for toxicology testing: • Stomach contents • Liver • Water • Initial testing: Strychnine, metaldehyde, Zinc/Al phosphide, OPs and carbamates
Planktothrix sp. ? Water sample from Eel River Lyngbya sp. Algae Identification Planktothrix spp.
B A C Cyanotoxins • LC/MS analysis • Confirmed presence of anatoxin-a in stomach contents and water
Algal toxins: Microcystins Anatoxin-a Domoic acid Saxitoxins Mushroom toxins Amanitins Mycotoxins Aflatoxin Tricothecenes Fumonisin Ochratoxin Zearalenone Penitrem A/Roquefortine Tests for Natural Toxins
Tests for Metals and Minerals • Metals: • Lead, arsenic, mercury, cadmium, manganese • Copper, zinc, selenium, molybdenum, iron • Thallium, barium, and many others • Minerals: • Calcium, magnesium, sodium, sulfur, potassium • Vitamins: • Vitamin A and E
TOXICOLOGISTS Dr. Birgit Puschner Dr. Robert Poppenga Dr. Asheesh Tiwary PHONE: (530) 752-6322 http://cahfs.ucdavis.edu/