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Xylene CAS#: 1330-20-7

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Xylene CAS#: 1330-20-7 PUBLIC HEALTH STATEMENT Xylene CAS#: 1330-20-7 Division of Toxicology and Environmental Medicine August 2007 This Public Health Statement is the summary breathing, eating, or drinking the substance, or by chapter from the Toxicological Profile for Xylene. skin contact. It is one in a series of Public Health Statements about hazardous substances and their health effects. If you are exposed to xylene, many factors will A shorter version, the ToxFAQsTM, is also determine whether you will be harmed. These available. This information is important because factors include the dose (how much), the duration this substance may harm you. The effects of (how long), and how you come in contact with it. exposure to any hazardous substance depend on the You must also consider any other chemicals you are dose, the duration, how you are exposed, personal exposed to and your age, sex, diet, family traits, traits and habits, and whether other chemicals are lifestyle, and state of health. present. For more information, call the ATSDR Information Center at 1-800-232-4636. __________________________________________ 1.1 WHAT IS XYLENE? This public health statement tells you about xylene In this report, the terms xylene, xylenes, and total and the effects of exposure to it. xylenes will be used interchangeably. There are three forms of xylene in which the methyl groups The Environmental Protection Agency (EPA) vary on the benzene ring: meta-xylene, ortho- identifies the most serious hazardous waste sites in xylene, and para-xylene (m-, o-, and p-xylene). the nation. These sites are then placed on the These different forms are referred to as isomers. National Priorities List (NPL) and are targeted for Drawings of the three different isomers are shown long-term federal clean-up activities. Xylene has in Chapter 4. The term total xylenes refers to all been found in at least 840 of the 1,684 current or three isomers of xylene (m-, o-, and p-xylene). former NPL sites. Although the total number of Mixed xylene is a mixture of the three isomers and NPL sites evaluated for this substance is not known, usually also contains 6–15% ethylbenzene. Xylene the possibility exists that the number of sites at is also known as xylol or dimethylbenzene. Xylene which xylene is found may increase in the future as is primarily a synthetic chemical. Chemical more sites are evaluated. This information is industries produce xylene from petroleum. Xylene important because these sites may be sources of also occurs naturally in petroleum and coal tar and exposure and exposure to this substance may harm is formed during forest fires, to a small extent. It is you. a colorless, flammable liquid with a sweet odor. When a substance is released either from a large Xylene is one of the top 30 chemicals produced in area, such as an industrial plant, or from a container, the United States in terms of volume. It is primarily such as a drum or bottle, it enters the environment. used as a solvent (a liquid that can dissolve other Such a release does not always lead to exposure. substances) in the printing, rubber, and leather You can be exposed to a substance only when you industries. Along with other solvents, xylene is also come in contact with it. You may be exposed by widely used as a cleaning agent, a thinner for paint, __________________________________________________________________________________________ DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service Agency for Toxic Substances and Disease Registry www.atsdr.cdc.gov/ Telephone: 1-800-232-4636 Fax: 770-488-4178 E-Mail: [email protected] PUBLIC HEALTH STATEMENT Xylene CAS#: 1330-20-7 Division of Toxicology and Environmental Medicine August 2007 and in varnishes. Xylene is used, to a lesser extent, Any xylene that does not evaporate quickly from as a material in the chemical, plastics, and synthetic soil or water is broken down by small organisms. fiber industries and as an ingredient in the coating Only very small amounts are taken up by plants, of fabrics and papers. Isomers of xylene are used in fish, and birds. the manufacture of certain polymers (chemical compounds), such as plastics. Xylene is found in Xylene below the soil surface may travel down small amounts in airplane fuel and gasoline. through the soil and enter underground water (groundwater). Xylene may remain in groundwater Xylene evaporates and burns easily. Xylene does for several months before it is finally broken down not mix well with water; however, it does mix with by small organisms. If a large amount of xylene alcohol and many other chemicals. Most people enters soil from an accidental spill, a hazardous begin to smell xylene in air at 0.08–3.7 parts of waste site, or a landfill, it may travel through the xylene per million parts of air (ppm) and in water at soil and contaminate drinking water wells. 0.53–1.1 ppm. 1.3 HOW MIGHT I BE EXPOSED TO 1.2 WHAT HAPPENS TO XYLENE WHEN IT XYLENE? ENTERS THE ENVIRONMENT? Xylene is primarily released from industrial Xylene is a liquid, and it can leak into soil, surface sources, in automobile exhaust, and during its use as water (creeks, streams, rivers), or groundwater. a solvent. Hazardous waste disposal sites and spills Xylene can enter the environment when it is made, of xylene into the environment are also possible packaged, shipped, or used. Most xylene that is sources of exposure. You are most likely to be accidentally released evaporates into the air, exposed to xylene by breathing it in contaminated although some is released into rivers or lakes. air. Typical levels of xylene measured in outdoor Xylene can also enter soil, water, or air in large air in the United States range from 1 to 30 parts of amounts after an accidental spill or as a result of an xylene per billion parts of air (a part per billion environmental leak during storage or burial at a [ppb] is one thousandth of a part per million [ppm]; waste site. one ppm equals 1,000 ppb). Typical levels of xylene measured in indoor air range from 1 to Since xylene evaporates easily, most xylene that 10 ppb. gets into soil and water (if not trapped underground) is expected to go into the air where it is broken Xylene is sometimes released into water and soil as down by sunlight into other less harmful chemicals a result of the use, storage, and transport of within a couple of days. For this reason, xylene is petroleum products. Little information exists about rarely found in high concentrations in topsoil or the amount of xylene in surface water and soil. surface water (river, creeks) unless there has been a However, levels of xylene in contaminated recent spill or continuing source of contamination. __________________________________________________________________________________________ DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service Agency for Toxic Substances and Disease Registry www.atsdr.cdc.gov/ Telephone: 1-800-232-4636 Fax: 770-488-4178 E-Mail: [email protected] PUBLIC HEALTH STATEMENT Xylene CAS#: 1330-20-7 Division of Toxicology and Environmental Medicine August 2007 groundwater have been reported to be as high as body if eat or drink xylene-contaminated food or 10,000 ppb. water. Less often, xylene enters the body through the skin following direct contact. Xylene is rapidly You may be exposed to xylene by drinking or absorbed by your lungs after you breathe air eating xylene-contaminated water or food. Xylene containing it. The amount of xylene retained ranges is not commonly found in drinking water. When it from 50 to 75% of the amount of xylene that you is, the levels of xylene are typically below 2 ppb. inhale. Physical exercise increases the amount of Xylene has been found in many types of foods at xylene absorbed by the lungs. Absorption of xylene levels ranging from 1 to 100 ppb. in the gut after eating food or drinking water containing it is both rapid and complete. You may also come in contact with xylene from a Absorption of liquid xylene through the skin also variety of consumer products, including gasoline, occurs rapidly following direct contact with xylene, paint, varnish, shellac, rust preventives, and but absorption of xylene vapor through the skin is cigarette smoke. Breathing vapors from these types only about 12% of the amount absorbed by the of products can expose you to xylene. In some lungs. At hazardous waste sites, the most likely cases, indoor levels of xylene can be higher than ways you can be exposed are: breathing xylene outdoor levels, especially in buildings with poor vapors, drinking well water contaminated with ventilation. Skin contact with products containing xylene, and direct contact of the skin with xylene. xylene, such as solvents, lacquers, paint thinners Xylene passes into the blood soon after entering the and removers, and pesticides may also expose you body. to xylene. In people and laboratory animals, xylene is Besides painters and paint industry workers, others chemically changed, primarily in the liver, into a who may be exposed to xylene include biomedical different form that is more water soluble and is laboratory workers, distillers of xylene, wood rapidly removed from the body in urine. Some processing plant workers, automobile garage unchanged xylene also leaves in the breath from the workers, metal workers, and furniture refinishers. lungs within a few seconds after xylene is absorbed. Workers who routinely come in contact with Small amounts of breakdown products of xylene xylene-containing solvents in the workplace are the have appeared in the urine of people as soon as population most likely to be exposed to high levels 2 hours after breathing air containing xylene.
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