# NIOSH Pocket Guide to Chemical Hazards
Monomethyl aniline | CAS 100-61-8
C6H5NHCH3 | RTECS BY4550000
Synonyms & Trade Names MA, (Methylamino)benzene, N-Methyl aniline, Methylphenylamine, N-Phenylmethylamine | DOT ID & Guide 2294 153
Exposure Limits | NIOSH REL: TWA 0.5 ppm (2 mg/m3) [skin]
OSHA PEL†: TWA 2 ppm (9 mg/m3) [skin]
IDLH 100 ppm | Conversion 1 ppm = 4.38 mg/m3
Physical Description Yellow to light-brown liquid with a weak, ammonia-like odor.
MW: 107.2 | BP: 384°F | FRZ: -71°F | Sol: Insoluble
VP: 0.3 mmHg | IP: 7.32 eV |  | Sp.Gr: 0.99
Fl.P: 175°F | UEL: ? | LEL: ? |
Class IIIA Combustible Liquid: Fl.P. at or above 140°F and below 200°F.
Incompatibilities & Reactivities Strong acids, strong oxidizers
Measurement Methods NIOSH 3511
Personal Protection & Sanitation Skin: Prevent skin contact Eyes: Prevent eye contact Wash skin: When contaminated Remove: When wet or contaminated Change: No recommendation | First Aid (See procedures) Eye: Irrigate immediately Skin: Soap wash immediately Breathing: Respiratory support Swallow: Medical attention immediately
Respirator Recommendations NIOSH Up to 5 ppm: (APF = 10) Any supplied-air respirator Up to 12.5 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode Up to 25 ppm: (APF = 50) Any supplied-air respirator that has a tight-fitting facepiece and is operated in a continuous-flow mode/(APF = 50) Any self-contained breathing apparatus with a full facepiece/(APF = 50) Any supplied-air respirator with a full facepiece Up to 100 ppm: (APF = 2000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode 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 canister providing protection against the compound of concern/Any appropriate escape-type, self-contained breathing apparatus
Exposure Routes inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms Lassitude (weakness, exhaustion), dizziness, headache; dyspnea (breathing difficulty), cyanosis; methemoglobinemia; pulmonary edema; liver, kidney damage
Target Organs respiratory system, liver, kidneys, blood, central nervous system
See also: INTRODUCTION