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FENTHION
ICSC: 0655
Peer-Review Status: 11.10.2006 Validated
O,O-Dimethyl-O-(4-methylthio-m-tolyl) phosphorothioate
Phosphorothioic acid, O,O-dimethyl O-(3-methyl-4-(methylthio)phenyl) ester 
CAS #: 55-38-9 RTECS #: TF9625000
UN #: 3018
EC #: 015-048-00-8
EINECS #: 200-231-9
 		    Formula: C10H15O3PS2 / (H3CO)2PSOC6H3(CH3)SCH3
Molecular mass: 278.3

TYPES OF
HAZARD /
EXPOSURE 		ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Combustible. Liquid formulations containing organic solvents may be flammable. Gives off irritating or toxic fumes (or gases) in a fire.  NO open flames.  Use water spray, foam, powder, carbon dioxide. 
EXPLOSION      
 
EXPOSURE   PREVENT GENERATION OF MISTS! STRICT HYGIENE!  IN ALL CASES CONSULT A DOCTOR! 
Inhalation Dizziness. Nausea. Vomiting. Sweating. Pupillary constriction, muscle cramp, excessive salivation. Laboured breathing. Convulsions. Unconciousness.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Refer immediately for medical attention. 
Skin MAY BE ABSORBED! Further see Inhalation.  Protective gloves. Protective clothing.  Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention . Wear protective gloves when administering first aid. 
Eyes Blurred vision.  Wear face shield or eye protection in combination with breathing protection.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion Abdominal cramps. Diarrhoea. Nausea. Vomiting. Further see Inhalation. Pupillary constriction. Muscle cramps. Excessive salivation.  Do not eat, drink, or smoke during work. Wash hands before eating.  Rinse mouth. Give a slurry of activated charcoal in water to drink. Refer immediately for medical attention. 

SPILLAGE DISPOSAL
 		PACKAGING & LABELLING
Personal protection: chemical protection suit, protective gloves and filter respirator for organic gases and particulates adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in dry sand or inert absorbent. Then store and dispose of according to local regulations.  Do not transport with food and feedstuffs.
Severe marine pollutant. 
EC Classification
Symbol: T, N; R: 21/22-23-48/25-50/53-68; S: (1/2)-36/37-45-60-61 
UN Classification
UN Hazard Class: 6.1; UN Pack Group: III 
GHS Classification
Signal: Danger
Toxic if swallowed
Toxic in contact with skin
Causes damage to nervous system
Very toxic to aquatic life 
skull;toxiccancer;health hazenviro;aqua

EMERGENCY RESPONSE SAFE STORAGE
Transport Emergency Card: TEC (R)-61GT6-III.  Separated from strong oxidants and food and feedstuffs. Well closed. Keep in a well-ventilated room. Provision to contain effluent from fire extinguishing. Store in an area without drain or sewer access. 

IMPORTANT DATA
Physical State; Appearance
COLOURLESS OILY LIQUID WITH CHARACTERISTIC ODOUR. PALE YELLOWISH BRONZE LUMPS WITH METALLIC LUSTRE. 

Physical dangers
 

Chemical dangers
Decomposes on heating. This produces toxic fumes including phosphorus oxides and sulfur oxides. Reacts with oxidants. 

Occupational exposure limits
TLV: 0.05mg/m³ as TWA; (skin); A4 (not classifiable as a human carcinogen); BEI issued; (ACGIH 2006).
MAK (inhalable fraction): 0.2 mg/m³; Peak limitation category: II(2); Skin absorption (H); (DFG 2006). 

Routes of exposure
The substance can be absorbed into the body in hazardous amounts by inhalation, through the skin and by ingestion. 

Inhalation risk
A harmful contamination of the air will not or will only very slowly be reached on evaporation of this substance at 20°C; on spraying or dispersing, however, much faster. 

Effects of short-term exposure
Cholinesterase inhibition. The substance may cause effects on the nervous system. This may result in convulsions and respiratory failure. The effects may be delayed. Medical observation is indicated. 

Effects of long-term or repeated exposure
Cholinesterase inhibition. Cumulative effects are possible. See Acute Hazards/Symptoms. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Decomposes when heated
Melting point: 7.5°C
Relative density (water = 1): 1.25
Solubility in water at 20°C: none
Vapour pressure at 25°C: negligible
Relative vapour density (air = 1): 9.6
Flash point: 170°C
Auto-ignition temperature: 365°C
Octanol/water partition coefficient as log Pow: 3.17-4.8   		The substance is very toxic to aquatic organisms. This substance does enter the environment under normal use. Great care, however, should be taken to avoid any additional release, for example through inappropriate disposal. 

NOTES
The technical grade (95-98% pure) is a yellow to brown oil with a weak garlic-like odour.
Carrier solvents used in commercial formulations may change physical and toxicological properties.
Do NOT take working clothes home.
Depending on the degree of exposure, periodic medical examination is suggested.
Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available. 

ADDITIONAL INFORMATION
 

IPCS
International
Programme on
Chemical Safety 		WHO ILO EC Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission
© IPCS 2004-2012
LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible for the use which might be made of this information. 
    See Also:
       Toxicological Abbreviations
       Fenthion (PDS)
       Fenthion (WHO Pesticide Residues Series 1)
       Fenthion (WHO Pesticide Residues Series 5)
       Fenthion (Pesticide residues in food: 1977 evaluations)
       Fenthion (Pesticide residues in food: 1978 evaluations)
       Fenthion (Pesticide residues in food: 1979 evaluations)
       Fenthion (Pesticide residues in food: 1980 evaluations)
       Fenthion (Pesticide residues in food: 1983 evaluations)
       Fenthion (Pesticide residues in food: 1995 evaluations Part II Toxicological & Environmental)
       Fenthion (Pesticide residues in food: 1995 evaluations Part II Toxicological & Environmental)
       Fenthion (Pesticide residues in food: 1997 evaluations Part II Toxicological & Environmental)