Tetraethyl lead, toxicity

Segregation is practised to allow for housekeeping, construction and maintenance requirements and to reduce the risk of an accident resulting in a domino effect , e.g. from a fire, explosion or toxic release. For very toxic substances, e.g. prussic acid (HCN) or tetraethyl lead, this may involve isolating the entire manufacturing operation in a separate unoccupied building or sealed-off area. 

No broad study of tetraethyl lead was conducted. According to Kehoe, It was thought that these necessarily extensive studies should not be repeated at present, at public expense, but that they should be continued at the expense of the industry most concerned. Kehoe proudly declared later, The problem [of tetraethyl lead s toxicity] therefore was left to a very substantial extent in our hands, where it has remained ever since. Such cooperative arrangements were typical of the 1920s in lieu of direct government regulation, industrial groups volunteered to collect technical information about the air and water pollution they caused. 

Deputy Surgeon General L. H. Gehrig spoke frankly Some maintain that a large segment of the population is already perilously close to the threshold of lead toxicity as a result of environmental exposure others take an almost diametrically opposed position. He also conceded that across the entire range of environmental health problems, we are making a rather belated start. Until the conference, the USPHS had focused on hydrocarbons and sulfur dioxide and rarely referred to tetraethyl lead as a pollution problem. 

A solid waste containing lead or lead compounds may be defined as a hazardous waste if it exhibits the characteristic of toxicity. The waste is said to exhibit the toxicity characteristic if the lead concentration in the extract obtained by subjecting a sample of the waste to the TCLP exceeds 5.0 mg/L. Tetraethyl and tetraethyl lead are combustible. If they are in sufficient quantity in a waste, tetraethyl lead may show an ignitability characteristic. More details on the regulatory requirements are presented in Chapter 7. 

Kehoe RA. 1927. On the toxicity of tetraethyl lead and inorganic lead salts. J Lab Clin Med 7 554-560. 

Other human toxicity values have not been established or have not been published. However, based on available information, this material appears to be approximately one-third as toxic as Tetraethyl lead (C11-A103). 

In the environment, metals are common as a chemical species, and as usual the metal-organic species are more toxic. For example, the inorganic lead and mercury species are less toxic for living organisms than the organic ones (methyl mercury, tetraethyl lead). However inorganic arsenic compounds are more toxic than organic... 

Tetraethyl lead was the major additive blended into gasolines in the past, and it must be carefully handled because of its high toxicity if it is still used. Sludges from finished gasoline storage tanks can contain large amounts of lead if tetraethyl lead is still used and should not be washed into the wastewater system. 

Tetraethyl lead is a highly toxic compound manifesting both acute and chronic effects. These effects are insomnia, hypotension, hypothermia, tremor. 

Organic lead is probably more toxic than inorganic lead, as it is lipid soluble. For example, triethyl lead, which results from breakdown of tetraethyl lead, is readily absorbed through the skin and into the brain and will cause encephalopathy. Symptoms are delusions, hallucinations, and ataxia, and the effects are rapid. Organic lead, however, has no effect on heme synthesis. 

Ge Tetraethyl lead has been widely used as a gasoline additive to improve combustion but is being phased out because of the toxic hazard associated with all lead compounds. 

It has been shown that T lymphocytes have AChE located on the plasma membrane, while B cells are esterase negative (Szelenyi et al, 1982). Thus, AChE inhibition by toxic agents in sublethal doses may play an important role in immunodeficiency following exposure to nerve gases. Zabrodskii et al (2003) showed inhibition of AChE in T cells and the decrease in the number of esterase-positive T lymphocytes (and, to a certain extent, in monocytes and macrophages) directly correlated with suppression of T cell-dependent antibody production and to the degree of DTH reduction, on exposure to dimethyl dichlorovinyl phosphate, sarin, VX, lewisite, tetraethyl lead, and dichloroethane. This presumably involves the loss of some functions by T... 

Acute lead exposure can lead to renal toxicity. The acute intraperitoneal LD50 for lead acetate in rodents is 100-200 mg kg Lead acetate is considerably less toxic by the oral route (LD5o>4gkg in rats). The acute oral LD50 of tetraethyl lead in rodents is 10-100 mg kg Acute organolead exposure can... 

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