International Chemical Safety Cards CROTONIC ACID ICSC: 0423 trans-2-Butenoic acid beta-Methylacrylic acid alpha-Crotonic acid 3-Methylacrylic acid C4H6O2 / CH3CH=CHCOOH Molecular mass: 86.09 ICSC #    0423 CAS #     3724-65-0 RTECS # GQ2800000 UN #        2823 March 27, 1996 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Combustible. NO open flames. NO contact with strong oxidants. NO contact with hot surfaces. Powder, water spray, foam, carbon dioxide. EXPLOSION Above 88°C explosive vapour/air mixtures may be formed. Finely dispersed particles form explosive mixtures in air. Above 88°C use a closed system, ventilation, and explosion-proof electrical equipment. In case of fire: keep drums, etc., cool by spraying with water. EXPOSURE PREVENT DISPERSION OF DUST! STRICT HYGIENE! IN ALL CASES CONSULT A DOCTOR!  •INHALATION Burning sensation. Cough. Headache. Nausea. Shortness of breath. Sore throat. Symptoms may be delayed (see Notes). Local exhaust or breathing protection. Fresh air, rest. Half-upright position. Artificial respiration if indicated. Refer for medical attention.  •SKIN Skin burns. Burning sensation. Pain. Protective gloves. Protective clothing. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention.  •EYES Pain. Blurred vision. Severe deep burns. Safety goggles, or eye protection in combination with breathing protection. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor.  •INGESTION Pain. Burning sensation. Diarrhoea. Sore throat. Vomiting. Do not eat, drink, or smoke during work. Rinse mouth. Do NOT induce vomiting. Rest. Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Consult an expert! Let solidify. Sweep spilled substance into containers, then remove to safe place. (Extra personal protection: complete protective clothing including self-contained breathing apparatus). Separated from food and feedstuffs , bases , oxidants , reducing agents. Dry. Keep in the dark. Airtight. Do not transport with food and feedstuffs. Unbreakable packaging. R: S: UN Hazard Class: 8 UN Packing Group: III SEE IMPORTANT INFORMATION ON BACK ICSC: 0423 Prepared in the context of cooperation between the International Programme on Chemical Safety & the Commission of the European Communities (C) IPCS CEC 1994. No modifications to the International version have been made except to add the OSHA PELs, NIOSH RELs and NIOSH IDLH values.

International Chemical Safety Cards CROTONIC ACID ICSC: 0423 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: WHITE TO YELLOW CRYSTALS , WITH PUNGENT ODOUR. PHYSICAL DANGERS: CHEMICAL DANGERS: The substance may polymerize under the influence of UV-light or moisture. The solution in water is a weak acid. Reacts violently with bases , oxidants , reducing agents . causing fire and explosion hazard. OCCUPATIONAL EXPOSURE LIMITS: TLV not established. ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation of its aerosol and by ingestion. INHALATION RISK: EFFECTS OF SHORT-TERM EXPOSURE: Corrosive. The substance is corrosive to the eyes, the skin and the respiratory tract. Corrosive on ingestion. Inhalation of the vapour may cause lung oedema (see Notes). The effects may be delayed. Medical observation is indicated. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: PHYSICAL PROPERTIES Boiling point: 189°C Melting point: 72°C Relative density (water = 1): 1.02 Solubility in water, g/100 ml at 25°C: 9.4 Vapour pressure, Pa at 20°C: 19 Relative vapour density (air = 1): 2.97 Flash point: 88°C o.c. Auto-ignition temperature: 396°C ENVIRONMENTAL DATA N O T E S In general the substance will be transported as molten liquid. The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation are therefore essential. Immediate administration of an appropriate spray, by a doctor or a person authorized by him/her, should be considered. NFPA Code: H3; F2; R0 ADDITIONAL INFORMATION ICSC: 0423 CROTONIC ACID (C) IPCS, CEC, 1994

IMPORTANT LEGAL NOTICE: Neither NIOSH, the CEC or the IPCS nor any person acting on behalf of NIOSH, the CEC or the IPCS is responsible for the use which might be made of this information. This card contains the collective views of the IPCS Peer Review Committee and may not reflect in all cases all the detailed requirements included in national legislation on the subject. The user should verify compliance of the cards with the relevant legislation in the country of use. The only modifications made to produce the U.S. version is inclusion of the OSHA PELs, NIOSH RELs and NIOSH IDLH values.