- Synonyms: 3,3'Dimethylbenzidine
- OSHA IMIS Code Number: 2450
- Chemical Abstracts Service (CAS) Registry Number: 119-93-7
- NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: DD1225000; 14667
- NIOSH Pocket Guide to Chemical Hazards, o-Tolidine: Chemical description, physical properties, potentially hazardous incompatibilities, and more
- American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): Appendix A3 (Confirmed Animal Carcinogen with Unknown Relevance to Humans)
- National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 0.02 mg/m3 Ceiling (60 min); Potential carcinogen
- Carcinogenic Classification:
- International Agency for Research on Cancer (IARC): Group 2B, possibly carcinogenic to humans (3,3'-Dimethylbenzidine and 3,3'-dimethylbenzidine-based dyes) (PDF).
- National Toxicology Program (NTP): Reasonably anticipated to be a human carcinogen (3,3'- Dimethylbenzidine and Dyes Metabolized to 3,3'-Dimethlybenzidine) (PDF).
Monitoring Methods used by OSHA
Primary Laboratory Sampling/Analytical Method (SLC1):
- Coated Glass Fiber Filters (37 mm) in 3 piece cassette. Coating is Sulfuric Acid.
- maximum volume: 100 Liters
- maximum flow rate: 1.0 L/min
- current analytical method: Gas Chromatography; GC/ECD
- method reference: 2 (OSHA 71)
- sampling and analytical error: 0.13
- method classification: Fully Validated
- note: Within ten hours after sampling, transfer filter to glass vial containing 2 mL deionized water. Filters may be obtained by OSHA personnel from the Salt Lake Technical Center (SLTC).
Wipe Sampling Method:
- Glass Fiber Filter
- Limit the amount of bulk submitted to one gram or one mL.
Zorbax C18; 60% methanol 40% water; 1 mL/min; UV Det: 280; DL 0.01 ug/sample; C/P DB
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