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METHYL PARATHION
| CAS # | 298-00-0 |
|---|---|
| Formula |
C₈H₁₀NO₅PS |
| Synonyms |
azophos; O,O-dimethyl-O-p-nitrophenylphosphorothioate; parathion methyl; phosphorothioic acid O,O-dimethyl O-(p-nitrophenyl) ester |
| Physical description | White to tan, crystalline solid or powder with a pungent, garlic-like odor. | ||
|---|---|---|---|
| Boiling point | 289°F | Molecular weight | 263.23 |
| Freezing point/melting point | 99°F | Vapor pressure | 0.00001 mmHg |
| Flash point | Vapor density | 9.1 | |
| Specific gravity | 1.36 | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | 4 | NFPA fire rating | 1 |
| NFPA reactivity rating | 2 | NFPA special instruction | |
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1775 |
|---|---|
| Sampling group | |
| Sampler/Sampling media | OSHA versatile sampler (OVS-2) - 13 mm XAD-2 tube (270/140 mg) with GFF enclosed [SKC 226-30-16] |
| Sampling time* |
|
| Sampling volume (TWA)* |
480 L |
| Sampling flow rate (TWA)* |
1 L/min |
| Sampling volume (STEL/Peak/C)* |
|
| Sampling flow rate (STEL/Peak/C)* |
|
| Analytical method instruments | GC-FPD |
| Method reference | OSHA PV2112 (partially validated) |
| Notes |
|
| Special requirements |
|
* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.
| Wipe Sampler/Sampling media |
Wipe with GFF (37 mm), Type A/E [AP4003705] |
|---|---|
| Bulk Method |
Limit the amount of bulk submitted to 1 g or 1 mL. |
| Device | |||||
|---|---|---|---|---|---|
| Model/Type | |||||
|
Sampling information (see manufacturer instructions) |
|
OSHA PEL
8-hour TWA (ST) STEL (C) Ceiling Peak |
NIOSH REL
Up to 10-hour TWA (ST) STEL (C) Ceiling |
ACGIH TLV©
8-hour TWA (ST) STEL (C) Ceiling |
|||||
|---|---|---|---|---|---|---|---|
| PEL-TWA |
|
REL-TWA |
0.2 mg/m³ |
TLV-TWA |
0.02 mg/m³ (inhalable fraction and vapor) [2008] |
PEL-TWA |
0.2 mg/m³ |
| PEL-STEL |
|
REL-STEL |
|
TLV-STEL |
|
PEL-STEL |
|
| PEL-C |
|
REL-C |
|
TLV-C |
|
PEL-C |
|
| Skin notation |
N |
Skin notation |
Y |
Skin notation |
Y |
Skin notation |
Y |
|
Notes:
Not established |
Notes:
|
Notes:
BEI® |
Notes:
|
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| Health factors: See NIH-NLM PubChem. | IDLH | ||||||
| Carcinogenic classifications: IARC-3, TLV-A4 |
Notes:
|
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|
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
|
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Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Methyl parathion NIOSH: Pocket Guide to Chemical Hazards - Methyl parathion Literature References
|
Last Updated Date : 01/05/2021