化合物详情

USDA APHIS Chemical Effects: collection=usda_chemeffect&query_type=synonym&query='^7758-95-4$'

TERRESTRIAL FATE: Only a small fraction of lead in lead-contaminated soil appears to be in water-soluble form, 0.2-1% according to one report, although the fraction soluble in EDTA ranged from 43-67% of the total lead in soil. The EDTA extractable material should include the chelated metals ions held in the soil organic and organomineral complexes, although there is some evidence that the metal adsorbed on colloidal surfaces such as insoluble inorganic compounds may also be extracted. When 500 ppm lead was added to soil as the soluble chloride, it became insoluble within an hour of contact with the soil; this insolubility lasted the duration of a 42-day experiment. After 42 days, 0.7 and 70% were in the water-soluble and EDTA-soluble fractions, respectively. The percentage of lead in wa...

Occurs in nature as the mineral cotunnite.

NIOSH (NOES Survey 1981-1983) has statistically estimated that 4188 workers (961 of these were female) were potentially exposed to lead chloride in the US(1).

Symptions of chronic lead poisoning include reduced cognitive abilities, nausea, abdominal pain, irritability, insomnia, metal taste in the mouth, excess lethargy or hyperactivity, chest pain, headache and, in extreme cases, seizures, comas, and death. There are also associated gastrointestinal problems, such as constipation, diarrhea, vomiting, poor appetite, weight loss, which are common in acute poisoning. (A2, L21)

Lead poisoning is usually treated with chelation therapy using DMSA, EDTA, or dimercaprol. (L21)

Eight-month old dogs maintained on a high fat low calcium diet were administered a mixture of lead chloride, lead bromide and lead sulfate for prolonged periods at 4 different dose levels. Dogs on high levels of leads showed marked weight loss and GI symptoms followed by death. Two dogs on low lead levels developed neurological signs. Radiological investigations showed radiopaque particles in 27% of abdominal radiographs and "lead lines' in the distal radius of 3 dogs. Highest tissue lead levels were found in bones followed by liver and kidney, brain and spinal cord.

LD50: 27 mg/kg (Oral, Rat) (A582)

Lead is a neurotoxin and has been known to cause brain damage and reduced cognitive capacity, especially in children. Lead exposure can result in nephropathy, as well as blood disorders such as high blood pressure and anemia. Lead also exhibits reproductive toxicity and can results in miscarriages and reduced sperm production. (L21)

ACGIH Carcinogen - Confirmed Animal.

Oral (L136); inhalation (L136); dermal (L136)

Lead mimics other biologically important metals, such as zinc, calcium, and iron, competing as cofactors for many of their respective enzymatic reactions. For example, lead has been shown to competitively inhibit calcium's binding of calmodulin, interferring with neurotransmitter release. It exhibits similar competitive inhibition at the NMDA receptor and protein kinase C, which impairs brain microvascular formation and function, as well as alters the blood-brain barrier. Lead also affects the nervous system by impairing regulation of dopamine synthesis and blocking evoked release of acetylcholine. However, it's main mechanism of action occurs by inhibiting delta-aminolevulinic acid dehydratase, an enzyme vital in the biosynthesis of heme, which is a necesssary cofactor of hemoglobin. (...

Chronic Inhalation: 0.05 mg/m3 (L134)

0.007 mg/kg (WHO) /Lead; from table/

2A, probably carcinogenic to humans. (L135)

Lead, lead compounds: Reasonably anticipated to be a human carcinogen