Triethyltin bromide is an organotin compound. Tin is a chemical element with the symbol Sn and atomic number 50. It is a natural component of the earth's crust and is obtained chiefly from the mineral cassiterite, where it occurs as tin dioxide. Bromine is a halogen element with the symbol Br and atomic number 35. Diatomic bromine does not occur naturally, but bromine salts can be found in crustal rock. (7, 4, 6)
This compound belongs to the class of organic compounds known as organic metal halides. These are organic compounds containing metals and halogens. Some are ionic while others are covalently bonded.
Organotin compounds produce neurotoxic and immunotoxic effects. Organotins may directly activate glial cells contributing to neuronal cell degeneration by local release of pro-inflammatory cytokines, tumor necrosis factor-_, and/or interleukins. They may also induce apoptosis by direct action on neuronal cells. Organotin compounds stimulate the neuronal release of and/or decrease of neuronal cell uptake of neurotransmitters in brain tissue, including aspartate, GABA, glutamate, norepinephrine, and serotonin. This may be either a contributing factor to or result of the neuronal cell loss. The immunotoxic effects of organotins are characterized by thymic atrophy caused by the suppression of proliferation of immature thymocytes and apoptosis of mature thymocytes. Organotin compounds are believed to exert these effects by suppressing DNA and protein synthesis, inducing the expression of genes involved in apoptosis (such as nur77), and disrupting the regulation of intracellular calcium levels, giving rise to the uncontrolled production of reactive oxygen species, release of cytochrome c to the cytosol, and the proteolytic and nucleolytic cascade of apoptosis. The suppression of proliferation of immature thymocytes further results in the suppression of T-cell-mediated immune responses. Organotins are also endocrine disruptors and are believed to contribute to obesity by inappropriate receptor activation, leading to adipocyte differentiation. Inorganic tin triggers eryptosis, contributing to tin-induced anemia. Bromine is a powerful oxidizing agent and is able to release oxygen free radicals from the water in mucous membranes. These free radicals are also potent oxidizers and produce tissue damage. In additon, the formation of hydrobromic and bromic acids will result in secondary irritation. The bromide ion is also known to affect the central nervous system, causing bromism. This is believed to be a result of bromide ions substituting for chloride ions in the in actions of neurotransmitters and transport systems, thus affecting numerous synaptic processes. (8, 9, 3, 5, 1, 2)
Metabolism
Though tin metal is very poorly absorbed, tin compounds may be absorbed via oral, inhalation, or dermal routes, with organotin compounds being much more readily absorbed than inorganic tin compounds. Tin may enter the bloodstream and bind to hemoglobin, where it is distributed and accumulates mainly in the kidney, liver, lung, and bone. Organotin compounds may undergo dealkylation, hydroxylation, dearylation, and oxidation catalyzed by cytochrome P-450 enzymes in the liver. The alkyl products of dealkylation are conjugated with glutathione and further metabolized to mercapturic acid derivatives. Tin and its metabolites are excreted mainly in the urine and feces. Bromine is mainly absorbed via inhalation, but may also enter the body through dermal contact. Bromine salts can be ingested. Due to its reactivity, bromine quickly forms bromide and may be deposited in the tissues, displacing other halogens. (8, 5)
No indication of carcinogenicity to humans (not listed by IARC).
Uses/Sources
Not Available
Minimum Risk Level
Not Available
Health Effects
Breathing or swallowing, or skin contact with organotins, can interfere with the way the brain and nervous system work, causing death in severe cases. Organic tin compounds may also damage the immune and reproductive system. Bromine vapour causes irritation and direct damage to the mucous membranes. Elemental bromine also burns the skin. The bromide ion is a central nervous system depressant and chronic exposure produces neuronal effects. This is called bromism and can result in central reactions reaching from somnolence to coma, cachexia, exicosis, loss of reflexes or pathologic reflexes, clonic seizures, tremor, ataxia, loss of neural sensitivity, paresis, papillar edema of the eyes, abnormal speech, cerebral edema, delirium, aggressiveness, and psychoses. (7, 8, 9, 4, 5)
Symptoms
Inorganic or organic tin compounds placed on the skin or in the eyes can produce skin and eye irritation. Bromine vapour causes irritation and direct damage to the mucous membranes. Symptoms include lacrimation, rhinorrhoea, eye irritation with mucous secretions from the oropharyngeal and upper airways, coughing, dyspnoea, choking, wheezing, epistaxis, and headache. The bromide ion is a central nervous system depressant producing ataxia, slurred speech, tremor, nausea, vomiting, lethargy, dizziness, visual disturbances, unsteadiness, headaches, impaired memory and concentration, disorientation and hallucinations. This is called bromism. (8, 9, 5)
Treatment
EYES: irrigate opened eyes for several minutes under running water.
INGESTION: do not induce vomiting. Rinse mouth with water (never give anything by mouth to an unconscious person). Seek immediate medical advice.
SKIN: should be treated immediately by rinsing the affected parts in cold running water for at least 15 minutes, followed by thorough washing with soap and water. If necessary, the person should shower and change contaminated clothing and shoes, and then must seek medical attention.
INHALATION: supply fresh air. If required provide artificial respiration.
