Lethal dose values

Figure 15.5. The structures of synthesized analogues (3-8), PA and PB, and their minimal lethal dose values in mice expressed as mg/kg (11).

Data on acute i.p. toxicity are available for YTX and eight analogues [3] (for chemistry, see Chapter 13). The LD50 or lethal dose values for YTX varies between 100 and 750 [tg/kg body weight. This is partly explained by possible differences in susceptibilities between mouse strains... 

Studies after acute intraperitoneal injection (i.p.) of OA in adult mice revealed that the LD50 (median lethal dose) values for this toxin ranged from 192 to 225 pg/kg (Table 11.Recently, a LD50 value of 352 pg/kg was determined in mice for DTX-2, estimating for this compound a relative toxicity of 0.6 as compared to that of The minimum lethal dose of OA, DTX-1, and DTX-3 in adult mice was reported to be 200, 160, and 500 pg/kg, respectively. Furthermore, the semisynthetic OA derivatives 7-0-palmitoyl and 7-0-linoleoyl OA revealed a minimal lethal dose in adult mice of 100 pg/kg " (Table 11.1). Anyway, some of these studies did not detail the number of mice injected, their sttain, their gender, their age, or the range of the administered doses. 

Table 11 summarizes values for the median lethal dose (LD q) for several species. In case of massive exposure, convulsions must be controlled, and glucose, fluid balance, and uriaary output must be maintained. Medical surveillance requires checking for damage to the Hver, the organ that apparently sustains initial damage, and monitoring for changes ia the blood profile. 

Value is LD q = lethal dose low, ie, lowest dose of a substance iatroduced by any route other than inhalation, adrninistered over any given period of time ia a single or divided dosage that has been reported to have caused death in the test organism. 

The toxicity of many bleaching chemicals is also reflected in observed effect doses and concentrations. These measures include lowest pubHshed toxic concentration (TC q), concentration that is lethal to 50% of a specified population (LC q), lowest pubHshed lethal dose (LD q), and dose that is lethal to 50% of a specified population (LD q). Some relevant values of these are Hsted in Table 3. 

Health Hazards Information - Recommended Personal Protective Equipment Eye protection Symptoms Following Eiqzosure Dust irritates eyes in same way as any foreign material. Penetration of skin by fragments of metal is likely to produce local irritation, blisters, and ulcers which may become infected General Treatment for Exposure EYES flush with water to remove dust. SKIN treat as any puncture Toxicity by Inhalation (Threshold Limit Value) Data not available Short-Term Inhalation Limits Not pertinent Toxicity by Ingestion Oral LDLo (lowest lethal dose) = 230 mg/kg (dog) Late Toxicity Data not available Vtqtor (Gas) Irritant Characteristics Not pertinent Liquid or Solid Irritant Characteristics Data not available Odor Threshold Not pertinent. 

Median Lethal Dose (LD) The statistically derived single dose of a chemical that can be c.xpected to cause death in 50% of a given population of organisms under a defined set of experimental conditions. This figure has often been used to classify and compare toxicity among chemicals but its value for this purpose is doubtful. One commonly used classification of this kind is as follows ... 

All reliable lethal doses (LD50 values) for each species and for the acute- and intermediate-duration categories are recorded in Table 3-3 and plotted in Figure 3-2. 

Several of the commonly used rubber chemicals tike accelerators, retarders, antidegradants, etc. are classified as hazardous on account of values of LD50 (lethal dose 50%) [6]. Many of the guanidine... 

The inherent toxicity of a material is measured by tests on animals. It is usually expressed as the lethal dose at which 50 per cent of the test animals are killed, the LD50 (lethal dose fifty) value. The dose is expressed as the quantity in milligrams of the toxic substance per kilogram of body weight of the test animal. 

Witkin (1956) reported intravenous (iv), intraperitoneal (i.p.), and oral LD50 (lethal dose for 50% of the animals) values for mice and rats, and i.v. LD50 values for dogs. Similar to hydrazine, the route of administration had minimal... 

Earlier studies demanded calculation of an LD50 value (i.e. the quantity of the drug required to cause death of 50 per cent of the test animals). Such studies required large quantities of animals, were expensive, and attracted much attention from animal welfare groups. Its physiological relevance to humans was often also questioned. Nowadays, in most world regions, calculation of the approximate lethal dose is sufficient. 

Human consumers of meat from 1080-killed ducks would probably not be adversely affected after eating an average cooked portion (Temple and Edwards 1985). Moreover, oven-baking or grilling at temperatures >200°C will cause breakdown of 1080. For example, if a mallard received a triple lethal dose of 1080, then a 1-kg mallard would contain an estimated 14.4 mg of 1080. A 70-kg human would have to consume 25.4 kg of poisoned duck flesh to receive a lethal dose, as judged by LD50 values of 4.8 mg/kg BW for mallards and 5 mg/kg BW for humans. Theoretically, consumption of only two whole ducks poisoned by 1080 may cause transient toxicity (Temple and Edwards 1985). 

LD50 values and the lowest lethal doses for acute- and intermediate-duration exposures classify hexachloroethane as slightly toxic (Hodge and Sterner 1949). It is unlikely that exposures to hexachloroethane at levels found at hazardous waste sites would cause death in humans. 

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