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PARAQUAT (PARAQUAT DICHLORIDE)†
| CAS # | 4685-14-7 |
|---|---|
| Formula |
C₁₂H₁₄N₂+2 |
| Synonyms |
1,1'-dimethyl-4,4'-bipyridinium dichloride; N,N'-dimethyl-4,4'-bipyridinium dichloride; paraquat chloride; paraquat dichloride |
| Physical description | [herbicide] [Note: Paraquat may also be found commercially as a methyl sulfate | ||
|---|---|---|---|
| Boiling point | decomposes | Molecular weight | 257.18 |
| Freezing point/melting point | 572°F (decomposes) | Vapor pressure | <0.0000001 mmHg |
| Flash point | Vapor density | ||
| Specific gravity | 1.24 | Ionization potential | |
| Lower explosive limit (LEL) | Upper explosive limit (UEL) | ||
| NFPA health rating | NFPA fire rating | ||
| NFPA reactivity rating | NFPA special instruction | ||
| Vapor hazard ratio (VHR) | |||
| Historical exceedance percentage | |||
| Target organs | |||
| Analyte code (IMIS no.) | 1982 (respirable dust) |
|---|---|
| Sampling group | |
| Sampler/Sampling media | PTFE filter, 1 µm [SKC 225-2705] |
| Sampling time* | |
| Sampling volume (TWA)* | 40-1000 L |
| Sampling flow rate (TWA)* | 1-4 L/min |
| Sampling volume (STEL/Peak/C)* | |
| Sampling flow rate (STEL/Peak/C)* | |
| Analytical method instruments | HPLC-UV |
| Method reference | NIOSH 5003 (fully 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 | |
|---|---|
| Bulk Method |
| 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 |
0.5 mg/m³ (resp dust) |
REL-TWA |
0.1 mg/m³ (resp) |
TLV-TWA |
0.05 mg/m³ (inhalable particulate matter) [2017] |
PEL-TWA |
0.5 mg/m³ (total particulates), 0.1 mg/m³ (respirable sizes) |
| PEL-STEL | REL-STEL | TLV-STEL | PEL-STEL | ||||
| PEL-C | REL-C | TLV-C | PEL-C | ||||
| Skin notation |
Y |
Skin notation |
Y |
Skin notation |
Y |
Skin notation |
Y |
| Notes: | Notes: | Notes: |
Notes:
See footnote [n] |
||||
| Health factors: See NIH-NLM PubChem. | IDLH |
1 mg/m³ |
|||||
| Carcinogenic classifications: TLV-A4 | Notes: | ||||||
| AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: | |||||||
Additional Resources and Literature References
|
NOAA: CAMEO Chemicals - Paraquat dichloride NIOSH: Pocket Guide to Chemical Hazards - Paraquat (Paraquat dichloride) Literature References
|
Last Updated Date : 01/07/2021