Health effects of 4,4'-Methylenebis(2-chloroaniline) (MBOCA)
MBOCA is a synthetic chemical used in industry primarily to produce castable polyurethane parts. It also has a coating application when used in chemical reactions to "set" glues, plastics, and adhesives. Since plastics have many uses, MBOCA is used very frequently. Other names for MBOCA include 4,4'-methylenebis(2- chloroaniline), bis amine, DACPM, MCA, methylene bis ortho chloroaniline, and MOCA. The name MBOCA comes from methylene bis ortho chloro aniline. Pure MBOCA is a colorless solid, but MBOCA is usually made and used as yellow, tan, or brown pellets. If MBOCA is heated above 205°C it may decompose by itself. MBOCA has no odor or taste.
Pathways in the enviroment
MBOCA may enter the environment through disposal of solid waste from manufacturing plants that use MBOCA in castable polyurethane processing. MBOCA is not likely to evaporate from the soil or water into the air. However, it may enter the air as dust when it is used at production plants, or it may enter surface waters from the waste streams of these plants. Some of the MBOCA may be broken down by sunlight or by tiny organisms, too small to be seen without the aid of a microscope.
Most exposure to MBOCA occurs in the workplace. If you work with MBOCA, you may breathe small particles of it in the air or get it on your skin if you brush against a surface covered by MBOCA dust. There are several other ways to be exposed to MBOCA outside of the workplace. For example, you may be exposed to MBOCA if you live in an area where the soil is contaminated with MBOCA. You may also be exposed if you eat foods grown in soils that contain MBOCA. However, you are unlikely to drink water contaminated with MBOCA because it does not dissolve easily in water.
Pathways in the body
MBOCA can enter your bloodstream if you breathe it in the air, eat it, or get it on your skin. Results of studies in humans and animals show that MBOCA can enter your body very quickly through the skin or lungs. Once MBOCA is in your body, most of it leaves your body quickly. MBOCA and its breakdown products exit the body through the urine and feces. Results of studies in humans and animals show that most MBOCA exits the body within a few days of exposure. The small amount of MBOCA that may remain in your body after you are exposed is likely to break down or leave your body at a slow rate.
Studies of human exposure suggest that the small amounts of MBOCA usually found in the air or on surfaces in or near factories do not cause toxic effects, other than cancer. However, it is possible that acute exposure to a large amount of MBOCA, such as in the case of an industrial accident, may produce effects that we do not know very much about. Information on how MBOCA can affect your health is very limited, and we do not know if there are any long-term human health effects of exposure to MBOCA. MBOCA is suspected of causing bladder cancer and is considered a probable human carcinogen. Information is being gathered to determine whether bladder cancer in humans may be a result of a short-, medium-, or long-term exposure to MBOCA. We do not know if MBOCA causes birth defects in humans.
Results of studies in animals show that MBOCA can be harmful to the liver of exposed dogs and rats. MBOCA also causes cancer of the lungs, liver, breast, and bladder in animals. The Department of Health and Human Services has determined that MBOCA may reasonably be anticipated to be a carcinogen. The International Agency for Research on Cancer has determined that MBOCA is probably carcinogenic to humans. The EPA has determined that MBOCA is a probable human carcinogen.
There is a test that can measure MBOCA in your urine within a few hours of exposure. This test, however, will not detect exposure to MBOCA after a few days. This test may not be commonly available in your doctor's office.
Disclaimer: This article is taken wholly from, or contains information that was originally published by, the Agency for Toxic Substances and Disease Registry. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the Agency for Toxic Substances and Disease Registry should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.