# NIOSH Pocket Guide to Chemical Hazards
Malathion | CAS 121-75-5
C10H19O6PS2 | RTECS WM8400000
Synonyms & Trade Names S-[1,2-bis(ethoxycarbonyl) ethyl]O,O-dimethyl-phosphorodithioate; Diethyl (dimethoxyphosphinothioylthio) succinate | DOT ID & Guide 2783 152
Exposure Limits | NIOSH REL: TWA 10 mg/m3 [skin]
OSHA PEL†: TWA 15 mg/m3 [skin]
IDLH 250 mg/m3 | Conversion
Physical Description Deep-brown to yellow liquid with a garlic-like odor. [insecticide] [Note: A solid below 37°F.]
MW: 330.4 | BP: 140°F (Decomposes) | FRZ: 37°F | Sol: 0.02%
VP: 0.00004 mmHg | IP: ? |  | Sp.Gr: 1.21
Fl.P(oc): >325°F | UEL: ? | LEL: ? |
Class IIIB Combustible Liquid, but may be difficult to ignite.
Incompatibilities & Reactivities Strong oxidizers, magnesium, alkaline pesticides [Note: Corrosive to metals.]
Measurement Methods NIOSH 5600; OSHA 62
Personal Protection & Sanitation 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 chemical cartridge respirator with organic vapor cartridge(s) in combination with a dust, mist, and fume filter/(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 chemical cartridge respirator with a full facepiece and organic vapor cartridge(s) in combination with a high-efficiency particulate filter/(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister having a high-efficiency particulate filter/(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s) in combination with a dust, mist, and fume 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 a high-efficiency particulate filter/Any appropriate escape-type, self-contained breathing apparatus
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 mucus), headache; chest tightness, wheezing, laryngeal spasm
Target Organs Eyes, skin, respiratory system, liver, blood cholinesterase, central nervous system, cardiovascular system, gastrointestinal tract
See also: INTRODUCTION