Toxicosis from toxicity

HV160 Puls R., and J. A. Greenway. Fusario-toxicosis from barley in British Columbia. II. Analysis and toxicity of syspected barley. Can J Comp Med 1976 40(1) 16-19. 

Toxicity Consumption of seeds at 0.1 %-0.3% of body weight niay be toxics whereas toxicosis from green foliage requires dosages equalling 10%-20% of body weight. 

D. I Toxidty. Voluntary feed refusal often prevents full expression of oral toxicosis from conta-minated feeds. Fiowever, iJosing studies using parenteral injection and oral administration reveal that trichothecenes are potent toxicants. 

Under unusual circumstances, toxicity may arise from ingestion of excess amounts of minerals. This is uncommon except in the cases of fluorine, molybdenum, selenium, copper, iron, vanadium, and arsenic. Toxicosis may also result from exposure to industrial compounds containing various chemical forms of some of the minerals. Aspects of toxicity of essential elements have been pubhshed (161). 

Pharmacologically, carbofuran inhibits cholinesterase, resulting in stimulation of the central, parasympathetic, and somatic motor systems. Sensitive biochemical tests have been developed to measure cholinesterase inhibition in avian and mammalian brain and plasma samples and are useful in the forensic assessment of carbamate exposure in human and wildlife pesticide incidents (Bal-lantyne and Marrs Hunt and Hooper 1993). Acute toxic clinical effects resulting from carbofuran exposure in animals and humans appear to be completely reversible and have been successfully treated with atropine sulfate. However, treatment should occur as soon as possible after exposure because acute carbofuran toxicosis can be fatal younger age groups of various species are more susceptible than adults (Finlayson et al. 1979). Carbofuran labels indicate that application is forbidden to streams, lakes, or ponds. In addition, manufacturers have stated that carbofuran is poisonous if swallowed, inhaled, or absorbed through the skin. Users are cautioned not to breathe carbofuran dust, fumes, or spray mist and treated areas should be avoided for at least 2 days (Anonymous 1971). Three points are emphasized at this juncture. First, some carbofuran degradation... 

Employees at hazardous waste sites, employees at pesticide mixing and formulating plants, and farm workers are more likely to be exposed to disulfoton than individuals in other occupations. Neurotoxl effects have been observed in occupationally exposed persons. However, no human data were located to identify susceptible subpopulations. Animal data suggest that female animals and young animals are more susceptible to disulfoton toxicosis. Based on the results from animal studies, women and children could also be more susceptible than men to toxic effects of disulfoton. 

Herbivores biotransforms xenobiotics from natural or artificial sources to render them harmless. Disarming potentially toxic compounds is termed detoxication, while the term detoxification refers to correcting a state of toxicosis (Johns, 1990). Herbivores degrade secondary plant compounds in a variety of ways, starting in the mouth, and leading to excretion. 

The complexity of plant response to toxicants is even more apparent as biochemical information regarding toxicosis has become available. However, the biochemical information has arisen from individual studies and reflects the interests of many investigators and many points of view. The appreciation of and recognition of the basis of biochemical lesions as responses to air pollutants is essential if we are to progress in this important field. 

Six toxic metabolites have also been isolated from a strain of A. clavatus (strain MIT-M-18), which was one of several collected from mould-infested rice in a Thai household in which a child had died of an unidentified toxicosis.32 Two of these metabolites, tryptoquivaline (35) and nortryptoquivalone, had been isolated earlier from a different strain of A. clavatus, but the remainder were new. One of them behaves in very similar manner to norisotryptoquivaline (FTD) (36), but is not identical with it, and hence is formulated as nortryptoquivaline (42). A second metabolite contains one oxygen atom fewer than tryptoquivaline and gives a negative triphenyltetrazolium test for hydroxylamines since it can be oxidized (m-ClC6H4C03H) to tryptoquivaline, it has been formulated as deoxytryp-toquivaline (43). The third of these mycotoxins is deoxynortryptoquivalone (44), since it can be oxidized to nortryptoquivalone (45). Similarly, the last metabolite... 

Toxicity. The toxicity of Mn for chicks was recently reviewed (40). Signs of toxicosis have been shown to vary depending on type of diet used, mineral composition of the diet and on source of Mn. Heller and Penquite (41) reported that 4779 ppm Mn from MnC03 reduced chick growth and caused 52% mortality. More recently, similar levels of Mn were fed to chicks with only mild anemia and a slight growth depression observed (18,19,22). 

Arsenic toxicity from drinking water is a major public health concern in many countries throughout the world. If exposure is to the inorganic form, the kidneys are the target organ due to its involvement in in vivo biotransformation and elimination. Very few clinical cases of toxicity are reported in humans. Most clinical cases of toxicosis are reported in animals, especially cattle and dogs, by... 

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