Lethal dose definition

Tb allium, which does not occur naturaHy in normal tissue, is not essential to mammals but does accumulate in the human body. Levels as low as 0.5 mg/100 g of tissue suggest thallium intoxication. Based on industrial experience, 0.10 mg /m of thallium in air is considered safe for a 40-h work week (37). The lethal dose for humans is not definitely known, but 1 g of absorbed thallium is considered sufficient to kHl an adult and 10 mg/kg body weight has been fatal to children. In severe cases of poisoning, death does not occur earlier than 8—10 d but most frequently in 10—12 d. Tb allium excretion is slow and prolonged. For example, tb allium is present in the feces 35 d after exposure and persists in the urine for up to three months. 

Some articles, for example, include an identical table of effective and lethal doses of high potency Fentanyl derivatives. The estimated safety margins are as high as 30,000. I could find no source for these data. I sent out several inquiries but thus far have received no definitive answers. I also discussed the questions with Harry Salem, who continues to study the toxicology of opioids at Edgewood. He is hopeful that the concomitant use of drugs tailored to suppress the effect of potent opioids on respiration may produce much safer agents. 

The information presented in the various categories in a MSDS should pose no real difficulty to most technically trained persons. Some definitions of terms may need to be provided, such as LDjq (lethal dose, 50% of the time for the test species), if an individual is not accustomed to... 

In most situations, only a small fraction of events traversing the cell is causative. For instance, only one 1 of 6000 electrons traversing a cell nucleus will produce a lethal lesion [32]. A possibly more meaningful definition of low dose ( biological low dose) can be made in terms of these causative events (hits) by asking that the contribution of the quadratic term in dose be less than a certain fraction, say 10%, of the total effect. Let A be this limiting dose. By definition ... 

Definitive information regarding the acute toxicity of di-N-octylphthalate is not available. An estimated lethal oral dose in humans is between 0.5 and 15gkg, or between 1 oz equivalent to 29.6 mis and 1 qt equivalent to 0.96 liters in a 70 kg adult. Compounds that are structurally similar to di-N-oct-ylphthalate are known to irritate mucous membranes resulting in irritation of the eyes, throat, and upper respiratory tract passages and in gastrointestinal disturbances. There is evidence that some phthalates, such as di-s-octylphthalate, may be reproductive and developmental toxicants. Generally, the acute oral toxicity of alkylphthalates is low and the acute oral toxicity decreases as molecular weight increases. 

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