LD50

Common name Test type Animal LD50, mg/kg Company... 

Compound CAS Registry Number Test animal Route of exposure LD50 mg/kg... 

Compound CAS Registry Number LD50 log(l/D, )" Principal target organ... 

Compound CAS Registry Number LD50. mg/kg Test animal Reference... 

Toxicological data oial, g/kg mixed isomers rat LD50 = >3 45... 

Toxicity information Toxic hazard rating Hygiene standard (e.g. OLE, TLV) Maximum allowable concentration (MAC) Lethal concentration (LC50) Lethal dose (LD50) ... 

LD50 The ealeulated dose of ehemieal (mg per kg body weight) eausing death in 50% of test population. (The speeies of animal, route of administration, any vehiele used to dissolve or suspend the material, and the time period of exposure should be reported.)... 

Indicators of toxicity hazards include LD50, LC50, plus a wide range of in vitro and in vivo techniques for assessment of skin and eye indtation, skin sensitization, mutagenicity, acute and chronic dermal and inhalation toxicity, reproductive toxicology, carcinogenicity etc. 

The LD50 is the statistically derived single dosage of a substance that can be expected to cause death in 50% of the sample population. It is therefore an indicator of acute toxicity, usually determined by ingestion using rats or mice, although other animals may be used. LD50 is also determined by other routes, e.g. by skin absorption in rabbits. The values are affected by species, sex, age, etc. 

The LC50 is the lethal concentration of chemical (e.g. in air or water) that will cause the death of 50% of the sample population. This is most appropriate as an indicator of the acute toxicity of chemicals in air breathed (or in water, for aquatic organisms). Table 5.11 illustrates the use of LD50 values to rank the toxicity of substances. 

The LD50 varies according to species of animal, sex, age and health. 

LD50 (see Ch. 5), death occurring within 30 days. Erythema (reddening of skin) within 3 weeks. 

If a substance produces other effects that make it inadvisable to use the LD50 or LC50 value as the principal basis of classification, the substance should be classified according to the magnitude of these effects. 

Typical units for LDjq values are milligrams or grams of material per kilogram of body weight (mg/kg or g/kg, recall that 1 kg = 2.2 pounds). Never be exposed to an LD50 dose of a hazardous chemical- by definition, there is a 50% chance this will kill you and if you survive you are not going to be in good shape. Pay close attention to the permissible exposure level (PEL) instead. This is a more realistic determination of the maximum safe exposure to a material and is usually based on the known effects of the chemical on humans, rather than laboratory animals. 

---