International Chemical Safety Cards 1-PENTANETHIOL ICSC: 1521 Amyl mercaptan Pentyl mercaptan Amyl hydrosulfide 2-Methylbutyl mercaptan C5H12S / CH3(CH2)4SH Molecular mass: 104.2 ICSC #    1521 CAS #     110-66-7 RTECS # SA3150000 UN #        1111 April 20, 2004 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Highly flammable. Gives off irritating or toxic fumes (or gases) in a fire. NO open flames, NO sparks, and NO smoking. Powder, AFFF, foam, carbon dioxide. EXPLOSION Vapour/air mixtures are explosive. Closed system, ventilation, explosion-proof electrical equipment and lighting. In case of fire: keep drums, etc., cool by spraying with water. EXPOSURE  •INHALATION Headache. Nausea. Cough. Ventilation, local exhaust, or breathing protection. Fresh air, rest. Refer for medical attention.  •SKIN Redness. Pain. Protective gloves. Remove contaminated clothes. Rinse skin with plenty of water or shower.  •EYES Redness. Pain. Safety spectacles. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor.  •INGESTION Burning sensation in the throat and chest. Headache. Nausea. Do not eat, drink, or smoke during work. Rinse mouth. Give plenty of water to drink. Do NOT induce vomiting. Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Remove all ignition sources. Cover the spilled material with absorbent material. Sweep spilled substance into sealable containers. Do NOT wash away into sewer. Personal protection: filter respirator for organic gases and vapours. Fireproof. R: S: UN Hazard Class: 3 UN Packing Group: II SEE IMPORTANT INFORMATION ON BACK ICSC: 1521 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 1-PENTANETHIOL ICSC: 1521 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: COLOURLESS LIQUID , WITH CHARACTERISTIC ODOUR. PHYSICAL DANGERS: The vapour mixes well with air, explosive mixtures are formed easily. CHEMICAL DANGERS: The substance decomposes on burning producing toxic and corrosive fumes including hydrogen sulfide and sulfur oxides . Reacts with acids , bases and strong oxidants . OCCUPATIONAL EXPOSURE LIMITS: TLV not established. MAK not established. ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation of its aerosol. INHALATION RISK: No indication can be given about the rate in which a harmful concentration in the air is reached on evaporation of this substance at 20°C. EFFECTS OF SHORT-TERM EXPOSURE: The substance is irritating to the eyes , the skin and the respiratory tract . EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: PHYSICAL PROPERTIES Boiling point at 61.3 kPa: 126.6°C Melting point: -75.7°C Relative density (water = 1): 0.84 Solubility in water: none Vapour pressure, kPa at 25°C: 1.84 Relative vapour density (air = 1): 3.6 Relative density of the vapour/air-mixture at 20°C (air = 1): 1.05 Flash point: 18°C ENVIRONMENTAL DATA N O T E S Health effects of exposure to the substance have not been investigated adequately. NFPA Code: H2; F3; R0; ADDITIONAL INFORMATION ICSC: 1521 1-PENTANETHIOL (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.