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NIOSH

METHOMYL

ICSC: 0177

S-Methyl-N-(methylcarbamoyloxy)thioacetimidate
Ethanimidothioic acid, N-{{(methylamino)carbonyl}oxy}-, methyl ester
Methyl N-{(methylamino)carbonyloxy}ethanimidothioate
C5H10N2O2S
Molecular mass: 162.2
ICSC # 0177 		CAS # 16752-77-5
RTECS # AK2975000
UN # 2757
EC # 006-045-00-2
October 19, 2005 Validated
Fi, review at IHE: 10/09/89

TYPES OF HAZARD/ EXPOSURE

ACUTE HAZARDS/ SYMPTOMS

PREVENTION

FIRST AID/
FIRE FIGHTING

FIRE Combustible under specific conditions. Liquid formulations containing organic solvents may be flammable. Gives off irritating or toxic fumes (or gases) in a fire.
NO open flames.
Water spray, foam, powder, carbon dioxide.
EXPLOSION


EXPOSURE
PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF ADOLESCENTS AND CHILDREN!

•INHALATION Pupillary constriction, muscle cramp, excessive salivation. Muscle twitching. Dizziness. Headache. Sweating. Laboured breathing. Unconsciousness.
Local exhaust or breathing protection.
Fresh air, rest. Half-upright position. Refer for medical attention. See Notes.
•SKIN
Protective gloves.
Remove contaminated clothes. Rinse skin with plenty of water or shower.
•EYES Redness. Blurred vision.
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 Abdominal cramps. Convulsions. Diarrhoea. Nausea. Vomiting. Weakness. (Further see Inhalation).
Do not eat, drink, or smoke during work. Wash hands before eating.
Give a slurry of activated charcoal in water to drink. Refer for medical attention immediately.

SPILLAGE DISPOSAL

STORAGE

PACKAGING & LABELLING

Personal protection: P3 filter respirator for toxic particles. Do NOT let this chemical enter the environment. Sweep spilled substance into sealable containers; if appropriate, moisten first to prevent dusting. Carefully collect remainder, then remove to safe place.
Store in an area without drain or sewer access. Dry. Keep in a well-ventilated room. Separated from strong bases, food and feedstuffs .
Unbreakable packaging; put breakable packaging into closed unbreakable container. Do not transport with food and feedstuffs.
Marine pollutant.
T+ symbol
N symbol
R: 28-50/53
S: 1/2-22-36/37-45-60-61
UN Hazard Class: 6.1
UN Packing Group: II
ICSC: 0177 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.

METHOMYL

ICSC: 0177

I

M

P

O

R

T

A

N

T


D

A

T

A

PHYSICAL STATE; APPEARANCE:
WHITE CRYSTALS , WITH CHARACTERISTIC ODOUR.

PHYSICAL DANGERS:


CHEMICAL DANGERS:
The substance decomposes on heating and on burning producing toxic and corrosive fumes including nitrogen oxides, sulfur oxides, hydrogen cyanide, methylisocyanate. Reacts with strong bases .

OCCUPATIONAL EXPOSURE LIMITS:
TLV: 2.5 mg/m3 as TWA; A4 (not classifiable as a human carcinogen); BEI issued; (ACGIH 2005).
MAK not established.
OSHA PEL†: none
NIOSH REL: TWA 2.5 mg/m3
NIOSH IDLH: N.D. See: IDLH INDEX


ROUTES OF EXPOSURE:
The substance can be absorbed into the body by inhalation of its aerosol 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:
The substance is irritating to the eyes . The substance may cause effects on the nervous system , resulting in convulsions and respiratory depression . Cholinesterase inhibitor. Exposure far above the OEL may result in death.

EFFECTS OF LONG-TERM OR REPEATED EXPOSURE:
The substance may have effects on the blood , resulting in anaemia .

PHYSICAL
PROPERTIES

Melting point: 78°C
Density: 1.3
g/cm3
Solubility in water, g/100 ml at 25°C: 5.8
(moderate)
Vapour pressure, Pa at 25°C:
negligible
Octanol/water partition coefficient as log Pow: 1.24

ENVIRONMENTAL
DATA

The substance is very toxic to aquatic organisms. This substance may be hazardous in the environment; special attention should be given to birds and honey bees. This substance does enter the environment under normal use. Great care, however, should be given to avoid any additional release, e.g. through inappropriate disposal.

N O T E S

Methomyl is a mixture of (Z)- and (E)-isomers. If the pesticide is present in a formulation containing hydrocarbon solvents, vomiting should not be induced. Specific treatment is necessary in case of poisoning with this substance; the appropriate means with instructions must be available. If the substance is formulated with solvents also consult the ICSCs of these materials. 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. Du Pont 1179, Flytek, Lannate, Lanox, Methavin, Methomex, Nudrin are trade names.
Transport Emergency Card: TEC (R)-61GT7-II
Card has been partially updated in January 2008: see Ingestion First Aid.

ADDITIONAL INFORMATION



ICSC: 0177 METHOMYL
(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.
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