Acute toxicity information sources

Source for basic acute and chronic toxicity information. Prime-time cost is about SS per hour. 

What are the known acute toxic effects of the product based on human exposures Initially, one might say that such information usually does not exist since our society does not condone human experimentation involving products other than drugs. Conversely, it could be argued that such information could be obtained from unplanned human exposures but that these would only occur after the product had been placed on the market. Thus, the information would not be available to the label writer at the time that it was needed. While the former statement is usually true the latter is usually not. It is the unusual product that does not have several close relatives if not a twin already in the market place. Thus, such human exposure information probably exists. One source of such information is the National Poison Center Network whose resources will be described later in this chapter. Obviously, such exposure information is undeniably superior to all others since humans form the principal audience that is to be addressed by the first aid statements. Manufacturers should make every effort to obtain such information. As previously mentioned, the sole dependency on animal studies may lead to erroneous conclusions. 

Evaluate type of toxicity. Use the above sources of information to determine the type of toxicity associated with each chemical involved in the proposed experiment. Are any of the chemicals to be used acutely toxic or corrosive Are any of the chemicals to be used irritants or sensitizers Will any select carcinogens or possibly carcinogenic substances be encountered For many substances, it will be necessary to consult the listings of carcinogens in this chapter (see Tables 3.4 and 3.5) to identify chemical similarities to known carcinogens. Are any chemicals involved in the proposed experiment suspected to be reproductive or developmental toxins or neurotoxins ... 

Evaluate quantitative information on toxicity. Consult the information sources to determine the LD50 for each chemical via the relevant routes of exposure. Determine the acute toxicity hazard level for each substance, classifying each chemical as highly toxic, moderately toxic, slightly toxic, and so forth. For substances that pose inhalation hazards, take note of the threshold limit value time-weighted average (TLV-TWA), short-term exposure limit (STEL), and permissible exposure limit (PEL) values. 

Scientific information for the process of establishing OELs may come from human or animal data obtained using different methods, from studies of acute, subacute, and chronic toxicity through various routes of entry. Human data, which is usually the best source, is not easily available, and frequently it is incomplete or inadequate due to poor characterization of exposure and clear dose-response relationships. Human data falls into one of the following categories ... 

The PAN Pesticide Database brings together a diverse array of information on pesticides from many different sources, providing human toxicity (chronic and acute), ecotoxicity and regulatory information for about 5400 pesticide active ingredients and their transformation products, as well as adjuvants and solvents used in pesticide products. ... 

IPCS Environmental Health Criteria Documents reflect the collective view of an international group of experts and do not necessarily represent the decision or stated policy of UNEP, ILO, or WHO. The reports summarize and interpret the pertinent published literature. Unpublished information is used when published information is absent or when data are pivotal to the risk assessment. Adequate human data are preferred to animal data. Topics include physical chemistry sources of exposure environmental fate and transport concentrations in the environment and in humans pharmacokinetics effects from acute, subacute, and long-term exposure toxic effects on skin, eye, and reproduction mutagenesis and cancer. 

Molybdenum occurs naturally in various ores the principal source being molybdenite (MoS ). Molybdenum compounds are used primarily in the production of metal allo). Molybdenum is also considered an essential trace element with the provisional recommended dietary intake of 75-250 pg/day for adults and older children. There is no information available on the acute or subchronic oral toxicity of molybdenum in humans. Subchronic and chronic Reference Concentrations (RfC) for Mo are not available. Information on the inhalation toxicity of Mo in humans following acute and subchronic exposures is also not available. The chronic oral Reference Dose (RfD) for Mo and Mo compounds is 0.005 mg/kg/day, based on biochemical indices in humans. The subchronic RfD is also 0.005 mg/kg/day. Mo is placed in EPA Group D, not classifiable as to carcinogenicity in humans. ... 

Plant toxins which act as hepatotoxins or abortifacients do not act as acute toxins. Their toxicity is of a more subtle, insidious nature with few outward manifestations until shortly before death (hepatotoxins) or abortion (abortifacients). In the case of range animals, the site and degree of exposure of a group of animals will often go unnoticed until an animal succumbs or aborts leaving the rancher with little information about either the toxic source or the location. The mode of action of these toxins dictates their consideration as toxins to humans, particularly in relation to their possible inclusion in herbal medicines and natural home remedies. 

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