Ingestion, of toxicants

Ingestion of toxic materials occurs only through accidental or careless procedures in the industrial environment and, while it caimot be ignored, it is seldom a significant factor in exposure. 

Generally, the main pathways of exposure considered in tliis step are atmospheric surface and groundwater transport, ingestion of toxic materials that luu c passed tlu-ough the aquatic and tcncstrial food chain, and dermal absorption. Once an exposure assessment determines the quantity of a chemical with which human populations nniy come in contact, the information can be combined with toxicity data (from the hazard identification process) to estimate potential health risks." The primary purpose of an exposure assessment is to... 

DeStefano, S., C.J. Brand, and M.D. Samuel. 1995. Seasonal ingestion of toxic and nontoxic shot by Canada geese. Wildl. Soc. Bull. 23 502-506. 

The role of these tastes has been nicely summarized Taste is in charge of evaluating the nutritious content of food and preventing the ingestion of toxic substances. Sweet taste permits the identification of energy-rich nutrients, umami allows the recognition of amino acids, salt taste ensures the proper dietary electrolyte balance, and sour and bitter warn against the intake of potentially noxious and/or poisonous chemicals. ... 

Workers exposed to an airborne fluoride concentration of 5mg/m complained of eye and respiratory tract irritation and nausea. The lethal oral dose of sodium fluoride for humans has been estimated to be 32-65 mg F/kg of body weight. Effects from ingestion are diffuse abdominal pain, diarrhea, and vomiting excessive salivation, thirst, and perspiration painful spasms of the limbs and sometimes albuminuria." Gastrointestinal effects produced after the acute ingestion of toxic amounts of fluoride likely arise from the corrosive action of hydrofluoric acid, which is produced within the acidic environment of the stomach. Cardiac arrest after accidental exposure to high levels of fluoride has been attributed to the development of hypocalcemia and/or hyperkalemia. ... 

Kulig K. Initial management of ingestions of toxic substances. N Engl J Med 1992 326 1677-81. 

Except in an emergency, running, or any over-hurried activity, should be forbidden in and around the laboratories, as should be practical jokes or other irresponsible behaviour. Eating, drinking and smoking in the laboratory should also be forbidden these constitute a further, avoidable, risk of the ingestion of toxic substances, and in the case of smoking an obvious fire hazard. 

Due to their lipophilicity TTA are rapidly and completely absorbed in the GIT and cross the blood-brain barrier allowing drug administration as tablets [29], Accordingly, severe intoxication may be caused after ingestion of toxic plants and berries. 

This aspect of poisoning is addressed in the last section introducing LC-MS methods for toxicological and forensic screening to detect toxic TA in body fluids after drug abuse or ingestion of toxic plants. 

Determination of risk following oral ingestion of toxicant... 

Carmichael, W.W., and Yuan, M.C.F. 2004. Human mortality from accidental ingestion of toxic cyanobacteria - A case re-examined. In Sixth international conference on toxic cyanobacteria, p. 61 (abstract), Bergen, Norway. 

Zatorre, R.J. 1990. Memory loss following domoic acid intoxication from ingestion of toxic mussels. CanDis WklyRep 16 Suppl IE, 101-103 discussion 103-104. 

Reisman R E 1994 Insect stings. New England Journal of Medicine 331 523-527 Shannon M 2000 Ingestion of toxic substances by children. New England Journal of Medicine 342 186-191... 

Calcification of the lung from vitamin D is rare, but has been reported in an infant after ingestion of toxic doses (15). 

Hansen SR, Janssen C, Beasley VR. Denatonium benzoate as a deterrent to ingestion of toxic substances toxicity and efficacy. Vet Hum Toxicol 1993 35(3) 234-236. 

Ingestion of toxic doses of barium affects the muscles, especially the heart. Barium has a digitalis-type effect on the heart. Ventricular fibrillation and slowed pulse rate are noted. This may be related to barium s tendency to displace potassium the resulting potassium deficiency causes muscle weakness. 

In the first few hours after the ingestion of toxic amounts of... 

Shannon M. Ingestion of toxic substances by children. N Engl J Med 2000 342 186-191. 

Humans accidentally exposed to high levels of selenium have been reported to have a noticeable garlic odor of the breath, probably as a result of excretion of dimethyl selenide in expired air (Bopp et al. 1982 Wilbur 1980). Garlic odor of the breath has been noted in humans following ingestion of toxic levels of sodium selenate (Civil and McDonald 1978) and following inhalation of elemental selenium dust or selenium dioxide (Glover 1970). 

---