3-Chloro-2-methyl-1-propene

PesticidesCarcinogen

3-Chloro-2-methyl-1-propene (also called methallyl chloride) is a flammable, irritating industrial chemical used to make other chemicals like pesticides and pharmaceuticals. It matters because even short-term exposure can strongly irritate the eyes, skin, and lungs, and spills can release harmful vapors.[1][2]

Where It Comes From

Made as a chemical intermediate; releases can occur during manufacturing, use, or transport; not naturally occurring.[2]

How You Are Exposed

Breathing vapors at work; skin contact; breathing air near industrial sites or spills; occasional lab use can affect indoor air.[1][2]

Why It Matters

Causes eye, skin, and respiratory irritation; higher levels may cause coughing, shortness of breath, headache, or dizziness; can be absorbed through skin; highly flammable.[1]

Who Is at Risk

Workers who make, use, or transport it; lab staff; emergency responders; people with asthma or eye/lung conditions may be more sensitive.[1]

How to Lower Your Exposure

At work, use closed systems, local exhaust, and appropriate gloves, goggles, and respiratory protection; store away from heat/ignition. In communities, avoid fumes during releases, ventilate indoor spaces, and report spills/odors to local authorities.[1][2]

References

[1]CDC/NIOSH Pocket Guide to Chemical Hazards: Methallyl chloride (3-chloro-2-methyl-1-propene), CAS 563-47-3. Centers for Disease Control and Prevention.
[2]U.S. EPA CompTox Chemicals Dashboard: 3-Chloro-2-methyl-1-propene (CASRN 563-47-3). Environmental Protection Agency.