Approximative lethal

Approximate lethal concentration, inhalation by tats, 4 h exposure unless noted otherwise. 

The Du Pont HaskeU Laboratory for Toxicology and Industrial Medicine has conducted a study to determine the acute inhalation toxicity of fumes evolved from Tefzel fluoropolymers when heated at elevated temperatures. Rats were exposed to decomposition products of Tefzel for 4 h at various temperatures. The approximate lethal temperature (ALT) for Tefzel resins was deterrnined to be 335—350°C. AH rats survived exposure to pyrolysis products from Tefzel heated to 300°C for this time period. At the ALT level, death was from pulmonary edema carbon monoxide poisoning was probably a contributing factor. Hydrolyzable fluoride was present in the pyrolysis products, with concentration dependent on temperature. 

Poly(tetramethylene ether) glycols were found to have low oral toxicity in animal tests. The approximate lethal oral dose, LD q, for Terathane 1000 has been found to be greater than 11,000 mg/kg (272). No adverse effects on inhalation have been observed. The polymer glycols are mild skin and eye irritants, and contact with skin, eyes, and clothing should be avoided. Goggles and gloves are recommended. In case of contact with the skin, wash thoroughly with water and soap. If swallowed, no specific intervention is indicated, because the compounds are not hazardous. However, a physician should be consulted (260). 

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. 

Calver, M.C., J.C. Mclhoy, D.R. King, J.S. Bradley, and J.L. Gardner. 1989b. Assessment of an approximate lethal dose technique for determining the relative susceptibility of non-target species to 1080 toxin. Austral. Wildl. Res. 16 33-40. 

Deichmann, W. and LeBlanc, T. (1943). Determination of the approximate lethal dose with about six animals. J. Ind. Hyg. Toxicol. 25 415—417. 

Oral toxicity. The approximate lethal dose of the dicyclo-hexyl-18-crown-6 polyether for ingestion by rats was 300 mg./ kg. In a 10-day subacute oral test, the compound did not exhibit any cumulative oral toxicity when administered to male rats at a dose level of 60 mg./kg./day. It should be noted that dosage at the approximate lethal dose level caused death in 11 minutes, but that a dose of 200 mg./kg. was not lethal in 14 days. 

Ingestion of the liquid has produced central nervous system depression with coma and loss of reflexes at doses in the range of 150mg/kg smaller doses have led to listlessness, headache, and vertigo 300mg/kg is considered to be the approximate lethal dose in humans. Chronic effects have not been reported from industrial exposure. 

The approximate lethal dose for skin absorption in pregnant rats and rabbits was 7.5 and 5.0g/kg, respectively Cutaneous application of DAIAC resulted in a marked incidence of embryo mortality at doses that did not affect maternal body weight or produce any signs of maternal toxicity. Teratogenic effects (three fetuses from one dam with encephalocele one of eight with diffuse subcutaneous edema) were found in rats only when DMAC was applied on gestation days 10 and 11 at a total dose of 2400 mg/kg. In another study, DMAC administered... 

In rats, 3 500 ppm for 4 hours was considered an approximate lethal concentration. Rats exposed 6 hours/day for 10 days to 0, 75, 250, or 750ppm had dose-dependent degenerative changes in the olfactory and respiratory epithelium. Degeneration of the tracheal mucosa was also observed at the two higher doses. 

In a later study by the same laboratory, HDl, undiluted or as a 5% solution in peanut oil, was administered via gavage to male albino ChR-CD rats, in single doses from 12 to 3,400 mg/kg. Animals receiving 3,400, 2,250, and 1,500 mg/kg died within 2-21 hours. Prior to death, these animals developed pallor, cyanosis, slow and deep breathing, and diarrhea. The approximate lethal dose (ALD) in that study was determined to be 1,500 mg/kg (Haskell Laboratory 1961). 

Rat once 1500M (approximate lethal dose) Haskell Laboratory... 

The dose levels should be chosen in a manner that significant toxicity can be induced. In rodents, a quantitative evaluation of the approximative lethal dose should be performed. 

In experimental animals, HFC-134a has been shown to have low toxicity via inhalation. An approximate lethal concentration in rats ranges from 567,000 to 750,000 ppm after 4-hr and 30-min exposures,... 

Approximate lethal doses for rats and rabbits by single oral administration were between 420 and 620 mg kg respectively. The animals showed diarrhea, lethargy, and decreased respiration. Rabbits were reported to show diffuse degenerative changes in the brain, heart, liver, and adrenal glands necrosis of the epithelium of renal tubules and severe hyperemia and edema of the lungs by skin absorption. 

How close do the above estimates relate to the actual LD50 Studies have shown that the approximate lethal dose for 86% of those chemicals tested in this manner were within 30% of the known LD50 values determined by the classical approach. The method is not infallible for example, some 14% of chemicals were outside this range and no dose-response or slope information can be obtained. International agreement has been reached that the up-and-down procedure could replace the conventional acute toxicity test for the purposes of hazard classification and label (including color-coding) production. 

Acute lethal concentrations (LC5°s) of airborne gasoline in experimental animals have not been reported. The acute oral LDsofor gasoline in rats has been reported to be 18.8 mL/kg, or approximately 14,063 mg/kg (Becketal. 1983 Vernot et al. 1990). This is higher than the approximate lethal dose estimated for humans cited above (12 ounces, which is equivalent to approximately 5 mL/kg, or 3,740 mg/kg). The lethal dose of gasoline following dermal exposure has not been determined in animals, but it does exceed 8.0 mL/kg, or 6,000 mg/kg, indicating that it is relatively nontoxic by the dermal route (Beck et al. 1983). Linder the exposure conditions expected to be present at hazardous waste sites, it is not expected that lethal air or water concentrations of gasoline will be achieved. 

The approximate lethal dose (ALD) of oral TNT exposure using northern bob-white (Colinus virginianus) was determined in a set of experiments using one individual of each sex at eight different oral exposures ranging from 263 to 4508 mg kg-1... 

Dicyclohexano-lS-crown-6, CMH36Oj, dicyclohexyl-18-crown-6". Causes eye, skin irritation in test animals. Approximate lethal dose in rats (mg/kg) 300 orally 130 skin absorption (Pedersen). 

II. Toxic dose. The approximate lethal oral dose of 95% ethylene glycol (eg, antifreeze) Is 1.5 mLAg however, survival has been reported after an ingestion of 2 L In a patient who received treatment within 1 hour of ingestion. 

Dodecahydro-do50-dodecaborate anion [B,2H,2] , the isoelectronic and isostructural analog of carboranes, is a typical representative of anionic polyhedral boron hydrides. Sodium salts of the parent cZo o-dodecaborate and their derivatives have a good solubility in water, which is an important precondition of many medical applications. The sodium salt Na2[Bj2Hj2] was found to be practically nontoxic with the approximate lethal dose for rats >7.5 g/kg of body weight, which is roughly comparable with that of sodium chloride [12], However, functionalization of this purely inorganic system till recently was problematic due to the absence of a clear reaction center. There are two... 

---