Malathion

Synonyms & Trade Names

Diethyl (dimethoxyphosphinothioylthio) succinate, S-[1,2-bis(ethoxycarbonyl) ethyl]O,O-dimethyl-phosphorodithioate

CAS No.

121-75-5

RTECS No.

WM8400000

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

Malathion

NIOSH REL

OSHA PEL

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