Food Toxicology Flashcards
What is a teratogen?
A substance that alters embryonic or fetal development in some manner to produce structural or functional alterations; causes birth defects
Aspergillus flavus and Aspergillus parasiticus produce liver toxins known as what?
Aflatoxins
Claviceps purpurea causes what type of food poisoning?
Ergotism
Define a food intoxication.
The organism grows in the food producing a toxin. The toxin is consumed and causes illness
Define a toxicoinfection.
Person consumes the organism and it multiplies in the gut where it produces a toxin, and the toxin makes the person sick.
Define carcinogen.
Agents which cause tumors that may be benign or malignant (cause cancer)
Give the name of a commonly used acute test for mutagenicity based on Salmonella Typhimurium.
Ames Test (Developed by Bruce Ames)
How is the histamine produced in scombroid poisoning?
Produced by bacterial decarboxylation of the generally large quantities of histidine in the fish muscles
In 1970, a Canadian chemist found what toxic element in fresh water fish?
Hg (mercury)
In 1973, the largest recorded outbreak of histamine poisoning occurred. It involved 2656 people who consumed dried horse mackerel. In what country did this outbreak occur?
Japan
In what units is the LD(50) reported?
mg/kg of body weight
Minimata disease was caused by the consumption of fish containing what element?
Mercury
Name of one of the toxic compounds in cassava
linamarin or lotoaustralin or isolinamarin (Cyanogenic Glucosides)
Name two fishes commonly associated with scombroid.
Tuna and mackerel
The chances for what food poisoning cannot be eliminated by reheating perishable foods that have been left out at room temperature for more than four hours?
Staphylococcus aureusfood poisoning
What are the three main stimulants found naturally in coffee, tea and cocoa?
Caffeine, Theophyllin, and Theobromine
What chemical from the oil of wormwood (once used in absinthe) causes lesions of the cerebral cortex?
Thujone
What element, if ingested by humans during pregnancy, can pass through the placenta to the fetus?
Mercury
What is a NOEL in toxicology?
No Effect Level
What is the breakdown product of Alar?
UDMH (Unsymmetrical dimethylhydrazine)
What is the cause of favism in those who consume fava beans?
Inherited deficiency of Glucose 6 Phosphate dehydrogenase
What is the difference in a toxin and a toxicant?
Toxicants are man-made chemicals and toxins are naturally occurring
What is the genus of the toxic mushroom known as the “Death Angel” and what is the name of the toxin?
Amanita; amatoxin or phallotoxin
What is the major group of enzymes in the liver that are responsible for Phase I metabolism of toxins?
Monoamine Oxidases (or could say monooxygeneases or P450 )
What is the maximum amount of aflatoxin allowed in food by FDA? Is this the lowest amount allowed in the World?
20 ppb (ng/g), 0.5 ppb for milk; No - 34 countries have lower action levels than U.S. - mostly EEC -( 0.05 ppb)
What is the most lethal of all fish poisons?
Saxitoxin or Puffer fish toxin (60 - 70% mortality)
What is the most toxic aflatoxin to humans?
B1
What is the name of the disease that wiped out vineyards in Europe?
Phylloxera
What is the popular trade name for daminozide?
Alar
What is the term for toxins produced by molds?
Mycotoxins
What is the toxic glycoside in Licorice that causes health problems when overconsumed?
Glycyrrhizin (hypertension, cardiac enlargement, na retention, etc.)
What mycotoxin is produced by a mold that can grow on moist peanuts, pecans, corn and other food stuffs?
Aflatoxin, Ochratoxin, Citrinin, Tricothecenes, and others
What quantity is defined as the dose of a substance which will kill 50% of the test subjects.
LD50
What term is used to describe the allowable tolerances of natural or unavoidable foreign material in foods that does not constitute a health hazard to the public?
Defect Action Level
What toxic alkaloid found in potatoes?
Solanine
What toxic alkaloid found in tomatoes?
Tomatine
What type botulism is mainly involved with seafood?
Type E
What type of immunoglobins are involved in food allergic responses?
IgE
Which foods besides fish are most often associated with histamine poisoning?
Fermented Foods - cheese, beer, wine, etc. (due to decarboxylation of amino acids)
Who developed the Human Exposure/Rodent Potency (HERP) Index?
Bruce Ames
Why do chelating agents increase the efficiency of antioxidants?
They bind trace metals that catalyze fat oxidation
Why has FDA banned sulfites on salad bars and required the labeling of wine containing sulfites?
Those with asthma can have life-threatening reactions to sulfites
Why is “glandless” cottonseed now cultivated in the United States for cottonseed meal production?
A highly toxic phenolic compound called Gossypol is found in the gland
Name six of the top eight allergens found in foods.
Fish, Shellfish, eggs, milk, soy, peanuts, treenuts, wheat
Overconsumption of certain foods is associated with gout; name four of these foods and explain why.
Beer, Wine, Alcohol, Organ Meats, Sardines, Anchovy, Herring, Meat, Yeasts, Asparagus, Mushroom, Spinach, Cauliflower; High Purine containing foods that are metabolized to uric acid
What are 2 types of intoxication associated with consuming seafood?
Ciguatera, scombroid, paralytic shellfish poisoning, puffer fish poisoning (tetrodotoxin)
What are 3 categories of botulism?
Foodborne, Infant, Wound
What are compositions and locations of exotoxins and endotoxins?
Exotoxin - proteins with little or no nonprotein residues, found outside of cell; Endotoxin - primarily polysaccharide and lipid complexes (lipopolysaccharides) associated with cell membrane
What are the 3 most common types of human botulism?
Type A, B, E
What are the foodborne bacterial intoxications?
Staphylococcal intoxication; Botulism; Bacillus cereus emetic syndrome
What are three major types of diffusion of toxins across membranes?
Passive, Facilitated, Active, Translocation
What causes rapeseed oil toxicity and how can this be prevented?
Erucic Acid; low EA varieties have been developed and should be used
What is the difference between a food allergy and a food intolerance?
True allergy is a whole body reaction, IgE mediated; intolerance is not.
What pink mold on celery causes a sensitization skin reaction in workers when they handle celery? What is the name of the toxin?
Sclerotinia sclerotiorum; Bergapten (or psoralen - general term)
