Target organs of toxicity

Identification of potential target organs of toxicity and reversibility of effect. 

NOTE For these categories the specific target organ/system that has been primarily affected by the classified substance may be identified, or the substance may be identified as a general systemic toxicant. Attempts should be made to determine the primary target organ of toxicity and classify for that purpose, e.g. hepatoxicants, neurotoxicants. One should carefully evaluate the data and, where possible, not include secondary effects, e.g. a hepatotoxicant can produce secondary effects in the nervous or gastro-intestinal systems. ... 

For chronic toxicity, only target organs of toxicity are reported. Detailed subdivision of animal species is superfluous. Doses do not have to be stated in detail as this may cause incorrect interpretations of safety mcirgins. Overall data may naturally be mentioned. 

The oral LD50 has been reported to be 500 mg kg in rats and 25 mg kg in dogs. The main target organ of toxicity is the bladder. 

Naphthalene ingestion can result in acute as well as delayed toxicity. The primary target organs of toxicity are the blood and eyes. Individuals deficient in glucose-6-phosphatase dehydrogenase are especially sensitive to the hemolytic effects of naphthalene. Normal individuals may also develop hemolysis when exposed to high doses. 

Acute ingestion of naphthalene by rabbits produced effects similar to those observed in humans. Rabbits fed acute doses of naphthalene presented browning of the lenses and eye humors and developed cataracts. In contrast to humans, where the major target organ of toxicity is the blood and eyes, for rats and mice the major target organ of toxicity is the lung. 

Phosphorus can be absorbed into the systemic circulation from the skin, lungs, and intestinal tract. For all practical purposes, white and yellow phosphorus are readily absorbed while red phosphorus is not. The target organs of toxicity include the gastrointestinal tract, liver, kidney, bone, and the cardiovascular and central nervous systems. 

Renal Effects. The available data suggest that the renal system is not a major target organ of toxicity for formaldehyde. Renal failure/anuria was noted in three case reports involving people ingesting various large or unknown amounts formaldehyde (Eells et al. 1981 Freestone and Bentley 1989 Koppel et al. 

In summary, no data are available regarding the toxicokinetics of the creosote mixture and all information must currently be inferred from what is known about the PAH components of creosote. Interactions between the components of the creosote mixture could occur that could alter the rate and extent of absorption, distribution, metabolism, and excretion of creosote from what might be predicted based on what is known about the individual PAH components. Therefore, more information on the toxicokinetics of the creosote mixture itself would be useful to predict possible target organs of toxicity as well as allow for extrapolation of toxic effects across routes of exposure. 

Most systemic toxicants predominantly affect one or a few organs. The target organ of toxicity is not necessarily the site of accumulation of the chemical. For example, lead is concentrated in bone, but its primary toxic action is on soft tissues DDT (chlorophenothane) is concentrated in adipose tissue but produces no known toxic effects there. 

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