The Risk Assessment Information System

RAGs A Format for Xylene - CAS Number 1330207

Xylene is a colorless, sweet-smelling liquid that catches on fire easily. Xylene is a volatile organic solvent widely used in chemical synthesis, consumer products, and agricultural chemicals. Xylene occurs naturally in petroleum and coal tar and is formed during forest fires; it is found in small amounts in airplane fuel and gasoline. Xylene, which is produced from petroleum, is one of the top 30 chemicals produced in the United States in terms of volume. Xylene is used as a solvent, a cleaning agent, a thinner for paint, in paints and varnishes, and in the printing, rubber, and leather industries.

Human exposure to xylene by either oral or inhalation routes can cause death due to respiratory failure accompanied by pulmonary congestion. High levels from exposure for short periods (14 days or less) or long periods (more than 1 year) can cause headaches, lack of muscle coordination, dizziness, confusion, and changes in balance. Exposure of humans to high levels of xylene for short periods can also cause irritation of the skin, eyes, nose, and throat; difficulty in breathing; problems with the lungs; delayed reaction time; memory difficulties; stomach discomfort; and possibly changes in the liver and kidneys. Studies of unborn animals indicate that high concentrations of xylene may cause increased numbers of deaths and delayed growth and development. In many instances, these same concentrations also cause damage to the mothers. It is not known whether xylene harms the unborn child if the mother is exposed to low levels of xylene during pregnancy.

Human and animal studies have not shown xylene to be carcinogenic, but these studies are lacking in information and are therefore not conclusive. EPA has placed xylene in weight-of-evidence group D, not classifiable as to human carcinogenicity. No significant increase in tumor incidence was observed in rats or mice of both sexes following oral administration of technical grade xylene.

The following is a presentation of the toxicity information associated with Xylene.

• The Oral Chronic Reference Dose is 2.00E+00 (mg/kg-day).
• The Oral Chronic Reference Dose has a modifying factor of 1.
• The Oral Chronic Reference Dose has an uncertainty factor of 100.
• The Oral Chronic Reference Dose is based on the NTP study from 1986.
• The Oral Chronic Reference Dose study critical effects are hyperactiviyy, decreased body weight, and increased mortality.
• The overall confidence in the Oral Chronic Reference Dose is medium.

• The Dermal Chronic Reference Dose is 1.84E+00 (mg/kg-day).
• The Dermal Chronic Reference Dose is based on a gastrointestinal absorption factor of 0.9200.

• The Oral Chronic Reference Dose is 2.00E+00 (mg/kg-day).
• The Oral Chronic Reference Dose has a modifying factor of 1.
• The Oral Chronic Reference Dose has an uncertainty factor of 100.
• The Oral Chronic Reference Dose is based on the U.S. EPA study from 1986.
• The Oral Chronic Reference Dose study target organ is central nervous system.
• The Oral Chronic Reference Dose study critical effect is Hyperactivity.

• The Dermal Chronic Reference Dose is 1.60E+00 (mg/kg-day).
• The Dermal Chronic Reference Dose is based on a gastrointestinal absorption factor of 0.8000.