Synonyms: Phosphorothioic Acid O,O-Dimethyl O-(p-Nitrophenyl) Ester

OSHA IMIS Code Number: 1775

Chemical Abstracts Service (CAS) Registry Number: 298-00-0

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: TG0175000; 59500

Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 2783 152 (solid) 3018 152 (liquid); NA2783(solid) NA3018(liquid) Poison

NIOSH Pocket Guide to Chemical Hazards, Methyl Parathion: chemical description, physical properties, potentially hazardous incompatibilities, and more

Chemical Description and Physical Properties:

solid
melting point: 37-38°C

American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 0.2 mg/m³ TWA (Skin); Appendix A4 (Not Classifiable as a Human Carcinogen)

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 0.2 mg/m³ TWA (skin)

Carcinogenic Classification:

International Agency for Research on Cancer (IARC): Group 3, not classifiable as to its carcinogenicity to humans [98 KB PDF, 37 pages]

Health Effects: Cholinesterase inhibition (HE6); Suspect teratogen (HE5) Mutagen (HE2); LD50 (oral, rat) 14-24 mg/kg HISTORY M108 assigned 3/82 by lab, corrected to 1775

Primary Laboratory Sampling/Analytical Method (SLC1):

• sampling media: OSHA Versatile Sampler (OVS-2) - 13 mm XAD-2 tube (270/140 mg sections, 20/60 mesh) with Glass Fiber Filter enclosed
  maximum volume: 480 Liters
  maximum flow rate: 1.0 L/min
  current analytical method: Gas Chromatography; GC/FPD
  method reference: 2 (OSHA In-House File)
  method classification: Partially Validated
  note: OSHA personnel may obtain sampling tubes from the Salt Lake Technical Center.

Conditions:

• column: 3% OV-17
  oven temperature: 170°C
  injection temperature: 250°C
  detection temperature: 225°C
  retention time: 5 min
  detection limit: 1.0 ug/sample; C/P WEB 4/82

Wipe Sampling Method:

sampling media: Glass Fiber Filter

Bulk Method:

• Limit the amount of bulk submitted to one gram or one mL.

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