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Malathion

Synonyms & Trade Names
Diethyl (dimethoxyphosphinothioylthio) succinate, S-[1,2-bis(ethoxycarbonyl) ethyl]O,O-dimethyl-phosphorodithioate
CAS No.
121-75-5
RTECS No.
DOT ID & Guide
2783 152
Formula
C₁₀H₁₉O₆PS₂
Conversion
IDLH
250 mg/m3
See: 121755
Exposure Limits
NIOSH REL
TWA 10 mg/m3 [skin]
OSHA PEL
TWA 15 mg/m3 [skin] See Appendix G
Measurement Methods
NIOSH 5600;
OSHA 62
See: NMAM or OSHA Methods
Physical Description
Deep-brown to yellow liquid with a garlic-like odor. [insecticide] [Note: A solid below 37°F.]
Molecular Weight
330.4
Boiling Point
140°F (Decomposes)
Freezing Point
37°F
Solubility
0.02%
Vapor Pressure
0.00004 mmHg
Ionization Potential
?
Specific Gravity
1.21
Flash Point
(oc) >325°F
Upper Explosive Limit
?
Lower Explosive Limit
?
Class IIIB Combustible Liquid: Fl.P. at or above 200°F., but may be difficult to ignite.
Incompatibilities & Reactivities
Strong oxidizers, magnesium, alkaline pesticides [Note: Corrosive to metals.]
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin; miosis, aching eyes, blurred vision, lacrimation (discharge of tears); salivation; anorexia, nausea, vomiting, abdominal cramps, diarrhea, dizziness, confusion, ataxia; rhinorrhea (discharge of thin nasal mucus), headache; chest tightness, wheezing, laryngeal spasm
Target Organs
Eyes, skin, respiratory system, liver, blood cholinesterase, central nervous system, cardiovascular system, gastrointestinal tract
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:Daily
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

Up to 100 mg/m3:
(APF = 10) Any air-purifying half-mask respirator with organic vapor cartridge(s) in combination with an N95, R95, or P95 filter. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.
(APF = 10) Any supplied-air respirator

Up to 250 mg/m3:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*
(APF = 50) Any air-purifying full-facepiece respirator equipped with organic vapor cartridge(s) in combination with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister having an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
(APF = 25) Any powered, air-purifying respirator with an organic vapor cartridge in combination with a high-efficiency particulate filter.*
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister having an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0172   MEDICAL TESTS: 0130
Page last reviewed: October 30, 2019