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Chlorodiphenyl (54% Cl)

General Description

  • Synonyms: Aroclor® 1254; PCB; Polychlorinated biphenyl
  • OSHA IMIS Code Number: 0631
  • Chemical Abstracts Service (CAS) Registry Number: 11097-69-1
  • Related Chemical Abstracts Service (CAS) Registry Numbers: 1336-36-3 (1,1'-Biphenyl, chloro derivs.); 27323-18-8 (1,1'-Biphenyl, chloro-)
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: TQ1360000
  • Department of Transportation Regulation Number (49 CFR 172.101) and Emergency Response Guidebook: 2315 171
  • NIOSH Pocket Guide to Chemical Hazards, Chlorodiphenyl (54% Chlorine): chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

  • American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): TWA; Skin; Appendix A3 - Confirmed Animal Carcinogen with Unknown Relevance to Humans
  • National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 0.001 mg/m3 TWA; Appendix A - NIOSH Potential Occupational Carcinogens [Note: The REL also applies to other PCBs.]

Health Factors

  • Carcinogenic Classification:
  • NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 5 mg/m3
  • Potential Symptoms: Irritation of eyes, chloracne; liver damage; reproductive effects; [potential occupational carcinogen] Ingestion: Headache, numbness; Skin Absorption
  • Health Effects: Chloracne/Cumulative liver damage (HE3)
  • Affected Organs: Skin, eyes, liver, reproductive system
  • Notes:
    1. Chlorodiphenyl is no longer produced or used in the U.S., except for limited research and development applications.
    2. In human hepatocyte cultures, 20 µM Aroclor 1254 reportedly activates the aryl hydrocarbon receptor and other transcription factors, which enables the activation of hundreds of genes to increase their expression (at least two-fold), such as the genes for cytochrome P450 1A1 and 1A2, as well as causing repression of expression of hundreds of other genes (by at least 50%).
    3. Incubation of human hepatocytes with Aroclor 1254 (≥3 µM) for 24 or more hours also increases the formation of DNA adducts.
    4. The half-lives in blood of various components of Aroclor 1254 in female rhesus monkeys treated chronically with Aroclor 1254 ranged from 0.3-7.6 years.
    5. Enhancement of the fecal elimination of Aroclor 1254 by chronic oral ingestion of olestra (~16 g/day for 2 years) has been suggested in one case of human intoxication in which the amount in fat tissue biopsies decreased from an initial measurement of 3200 mg/kg of fat to 56 mg/kg of fat.
  • Date Last Revised: 04/13/2007
  • Literature Basis:
    • NIOSH Pocket Guide to Chemical Hazards: Chlorodiphenyl (54% Chlorine).
    • International Chemical Safety Cards (WHO/IPCS/ILO): Polychlorinated Biphenyl (Arochlor 1254).
    • U.S. EPA Integrated Risk Information System: Polychlorinated Biphenyls (PCBs) (CASRN 1336-36-3).
    • Borlak, J., Hock, A., Hansen, T. and Richter, E.: DNA adducts in cultures of polychlorinated biphenyl-treated human hepatocytes. Toxicol. Appl. Pharmacol. 188(2): 81-91, 2003.
    • Mes, J., Arnold, D.L. and Bryce, F.: The elimination and estimated half-lives of specific polychlorinated biphenyl congeners from the blood of female monkeys after discontinuation of daily dosing with Aroclor 1254. Chemosphere 30(4): 789-800, 1995.
    • No Author: Polychlorinated Biphenyls CAS No. 1336-36-3 (PDF). Report on Carcinogens (latest edition); U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program.
    • Pohanish, R.P. (editor): Polychlorinated Biphenyls (PCBs). In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1902-1905.
    • Redgrave, T.G., Wallace, P., Jandacek, R.J. and Tso, P.: Treatment with a dietary fat substitute decreased Arochlor 1254 contamination in an obese diabetic male. J. Nutr. Biochem. 16(6): 383-384, 2005.
    • Reymann, S. and Borlak, J.: Transcriptome profiling of human hepatocytes treated with Aroclor 1254 reveals transcription factor regulatory networks and clusters of regulated genes. BMC Genomics 7: 217, 2006 (18 pp.).

Monitoring Methods used by OSHA

Laboratory Sampling/Analytical Method:
  • OSHA Versatile Sampler (OVS-2) - 13 mm XAD-2 Tube (270/140 mg sections, 20/60 mesh) with Glass Fiber Filter enclosed analytical solvent
  • maximum volume: 60 Liters
  • maximum flow rate: 1.0 L/min
  • current analytical method: Gas Chromatography; GC/ECD
  • method reference: OSHA Analytical Method (OSHA PV2088)
  • method classification: Partially Validated
  • note: Collect a sample of the bulk substance and send to the lab in a separate mailing container at the time the air samples are submitted. Indicate on the sample sheet that a bulk sample has been submitted.
Bulk Method:
  • Limit the amount of bulk submitted to one gram or one mL for oils and 20 g for soil.

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