Xylene

Latest Edit: Iva 2012-08-04 (EDT)

Xylene is one of many toxic environmental chemicals. Xylene is a natural component of petroleum and coal tar. It is used as motor and aviation fuel additive. The most common source of exposure if by inhalation of vapors.

Sources

• Automotive emissions, poor emission-control devices on older vehicles, poor maintenance practices, aviation fuel, waste and landfill sites, localized industrial discharges and spillage incidents, tobacco smoke.

• Household: topical contact or inhalation of varnish/polishers, paint, paint thinner, paint remover, shellac, rust preventatives, lacquers, inks, dyes, adhesives, cleaning fluids, degreasing agents, household cleaning products.

• Used as a solvent for rubbers, synthetic resins, gums, inks, paint.

• Fabric and leather treatments.

• Used in the synthesis of plasticizers and in the manufacture of polyester fiber, film, insecticide formulations, and perfumes.

• Industry: paint and printing ink industries, automobile body and related repairs, photographic processing, rubber, leather, plastics and textile industries, flooring contractor.

Effects

• Depression of the central nercous system.
• Neuropsychological and neurophysiological dysfunction.
• Anemia, thrombocytopaenia, renal damage.
• Irritation of mucous membranes, dermatitis, nausea, fatigue, headache, anxiety.
• Dyspnea, cyanosis

Metabolism

• Metabolized in the liver by cytochrome P-450 dependent multifunction oxidase enzymes. It is conjugated principally with glycine and excreted in the urine as methylhippuric acids. Conjugation with sulfate or glucuronic acid represents a minor pathway.

• Monitoring can be done through urinary levels of 2 or 3-methylhippurate. Although the 2-isomer exhibits a longer half-life, the 3-isomer is the principle component making up 45-70% of commercial xylene.

• Does not accumulate in bodily tissues.