Reducing Occupational Exposure to Benzene in Workers and Their Offspring

  • Date: Dec 14 2005
  • Policy Number: 20056

Key Words: Chemicals, Compensation, Occupational Health And Safety

Whereas,

The American Public Health Association has a long history of concern for the health and well-being of workers exposed to occupational hazards in the United States and abroad.1

The Occupational Safety and Health Act of 1970 (Public Law 91-596) was enacted to establish the Occupational Safety and Health Administration in order to assure so far as possible every working man and woman in the Nation safe and healthful working conditions.

The International Labour Organisation (ILO) adopted the convention concerning Protection Against Hazards of Poisoning Arising from Benzene in 1971.

Classified as a Class 1 Human Carcinogen and as a Reproductive Toxicant, benzene is well-recognized as a cause of leukemia and aplastic anemia in exposed workers, and has also been linked to immune abnormalities.2,5,16,18,22,25,33,34

Approximately 3 million workers in the United States and 1.4 million workers in the European Union, and unaccounted-for others in many industrializing economies, are exposed to benzene in industries such as adhesives, auto repair, chemical, gas station, paint, petroleum, rubber, shoe/leather, and shipping (Kauppinen et al., 2001; ATSDR, 1989). Over half of exposed workers may be women in industries such as shoe manufacturing and in countries with poor occupational health standards.18,8

The total U.S. production of benzene is approximately 15.8 billion pounds per year, which ranks in the top 20 highest volume chemicals produced in the United States.2,25 The total amount of benzene produced in the United States has increased on average 2.8 percent per year between 1992 and 2002.25

Benzene has been defined as a hazardous air pollutant, and one of the mobile source-related air toxics as it is released by automobiles, trucks and other non-road vehicles, in addition to industrial point sources. (USC, Title 42, Chapter 85 Subchapter I, Section 7412; USC, Title 42, Chapter 85, Section 7521). 

The general public may be exposed to benzene in tobacco smoke, contaminated water, contaminated food, gasoline fumes, automobile and other engine exhausts, with approximately half of the total national exposure due to tobacco smoke.25

Over 6 million pounds of benzene are released into the U.S. environment annually from point sources.35

Multiple sources of exposure (including point and non-point exposure) occur to workers whom also reside within disadvantaged communities that are more frequently exposed to a greater number of polluting sources, including benzene.15,21,27

Genetic variants related to benzene metabolism may predispose certain individuals to greater adverse effects of benzene exposure, and these genetic variants occur in a substantial proportion of the population.18,33

More recent evidence suggests that carcinogenic and toxic effects, including genotoxicity and immunotoxicity, occur among workers exposed to levels below OSHA's permissible exposure limit (1 ppm, 8-hour time weighted average).14,18

Benzene risk assessment models, which attempt to extrapolate risk from high exposure to low exposure scenarios, may under-estimate the level of true risk at low level exposures.14

Benzene crosses the human placenta and is found in human breast milk.16,12

Children and infants may be more susceptible to substances like benzene than adults.22

A possible relation between parental occupational and environmental exposure to benzene and elevated risk of leukemia and birth defects among their offspring exists.32,31,20,29,6,36

Engineering controls, administrative controls, work practice improvements, use of personal protective equipment and employee education can all be used to reduce benzene exposure to the work force.7,9

APHA has previously called for OSHA to adopt the NIOSH recommended exposure limits (APHA policy #8712).

APHA and other professional organizations have recognized that OSHA has not revised the permissible exposure limit to benzene since 1987 (nearly 20 years ago), and review of other workplace carcinogens is also needed.4,10,1

OSHA has been petitioned by experts in the field to lower the exposure limit to 0.1 ppm and that OSHA has declined this petition due to a constraint of resources, rather than on the absence of scientific evidence (Mehlman, 2004; OSHA, 2004; The Collegium Ramazzini, 2005).

The following are major shortfalls in OSHA regulation of benzene: 

  1. The current Occupational Safety and Health Administration regulations are not consistent with national consensus standards from outside expert organizations. OSHA's permissible exposure limit for an 8-hour time weighted average is 1 part per million, which is 2-fold higher than the level recommended by ACGIH (0.5 ppm), and 10-fold higher than that recommended by NIOSH and other experts (0.1 ppm). OSHA's permissible short term exposure limit is 5-times higher than recommended by NIOSH (5 ppm versus 1 ppm).3,10,24
  2. The dearth of information on sensitive subpopulations (e.g. children, pregnant women, older aged persons, and genetically-at-risk populations) and the dearth of information on the total burden of exposure from occupational and other environmental sources (e.g. environmental tobacco smoke, automobile combustion, and point-source emissions) combined hampers full risk assessment.22
Therefore, the American Public Health Association urges
  1. Congress to fully fund OSHA at a level necessary to review current scientific evidence on benzene to establish a new standard;
  2. OSHA to immediately update existing regulations by reducing benzene exposure limits to the lowest feasible level based on the best available scientific evidence. 
  3. OSHA to consider evidence from epidemiologic studies and risk assessments that consider multiple environmental sources of benzene exposure to benzene-exposed workers and potential effects in offspring as part of revising this standard;
  4. Congress to fund NIOSH and other relevant research entities to determine the level of benefits in morbidity, mortality and productivity of individuals and productivity level of affected industries by establishing standards for benzene and comparing pre- and post-regulation surveillance statistics.
  5. U.S. Congress to join the 36 countries that have ratified the ILO Convention of 1971 to confirm the U.S. Commitment to international reductions in benzene release.

References

  1. (APHA Policies #5609, 5705, 5713, 6507, 7111, 7224, 7416, 7224, 7416, 7417, 7523, 7715, 8102, 8115, 8213, 8313, 8329, 8416, 8509, 8603, 8606, 8716, 8710, 8714, 8712, 8807, 8810, 8917, 9108, 9203, 9304, 9404, 9405, 9503, 9703, 9806, 9912, 20014, 200121, 20027, 20019, 20039, 200403);
  2. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for benzene. U.S. Public Health Service, U.S. Department of Health and Human Services, Atlanta, GA. 1997. 
  3. 3. ACGIH Publication #0105.
  4. American Industrial Hygiene Association (2002) White Paper on Permissible Exposure Limits (PELs), approved by AIHA Board of Directors September 2002. (http://www.aiha.org/GovernmentAffairs-PR/html/GAWPpermexpo.htm)
  5. Biro A, Pallinger E, Major J, Jakab MG, Klupp T, Falus A, Tompa A. (2002) Lymphocyte phenotype analysis and chromosome aberration frequency of workers occupationally exposed to styrene, benzene, polycyclic aromatic hydrocarbons or mixed solvents. Immunol Lett. 22;81(2):133-40. 
  6. Bove FJ, Fulcomer MC, Klotz JB, Esmart J, Dufficy EM, Savrin JE. (1995) Public drinking water contamination and birth outcomes. Am J Epidemiol. May 1;141(9):850-62.
  7. Canadian Association of Petroleum Producers (CAPP) (2002) Best Management Practices for Control of Benzene Emissions from Glycol Dehydration. (Publication #2000-85).
  8. Chen MS, Chan A. China's "market economics in command": footwear workers' health in jeopardy. Int J Health Serv. 1999;29(4):793-811.
  9. Cohen, BS. Industrial Hygiene Measurement and Control. In W.M. Rom (ed.) Environmental and Occupational Medicine, 3rd Edition (Philadelphia: Lippincott-Raven) pp. 1741-1755.
  10. Collegium Ramazzini (2004) Call for a reduction of exposure to benzene to the lowest possible level. European Journal of Oncology. 9 (1):13.
  11. Environmental Protection Agency (EPA). (1998) Carcinogenic effects of Benzene: An Update. April 1998
  12. Fabietti F, Ambruzzi A, Delise M, Sprechini MR. (2004) Monitoring of the benzene and toluene contents in human milk. Environ Int. 30(3):397-401. 
  13. Hayes RB, Yin S, Rothman N, Dosemeci M, Li G, Travis LT, Smith MT, Linet MS. (2000) Benzene and lymphohematopoietic malignancies in China. J Toxicol Environ Health A. 2000 Nov;61(5-6):419-32. 
  14. Hayes RB, Yin SN, Dosemeci M, Li GL, Wacholder S, Travis LB, Li CY, Rothman N, Hoover RN, Linet MS. Benzene and the dose-related incidence of hematologic neoplasms in China. Chinese Academy of Preventive Medicine--National Cancer Institute Benzene Study Group. J Natl Cancer Inst. 1997 Jul 16;89(14):1065-71. 
  15. Hayes RB, Songnian Y, Dosemeci M, Linet M. (2001) Benzene and lymphohematopoietic malignancies in humans. Am J Ind Med. 40(2):117-26.
  16. Henderson RF, Sabourin PJ, Medinsky MA, Birnbaum LS, Lucier GL. (1992) Benzene dosimetry in experimental animals: relevance for risk assessment. Prog Clin Biol Res. 374:93-105.
  17. Institute of Medicine (1999) Toward Environmental Justice: Research, Education, and Health Policy Needs (Washington, D.C.: National Academies Press).
  18. International Agency for Research on Cancer (IARC) (1982). IARC monographs on the evaluation of the carcinogenic risk of chemicals to humans. Some industrial chemicals and dyestuffs. Vol. 29. (Lyon, France: IARC)
  19. Kauppinen T, Toikkanen J, Pedersen D, Young R, Ahrens W, Boffetta P, Hansen J, Kromhout H, Maqueda Blasco J, Mirabelli D, de la Orden-Rivera V, Pannett B, Plato N, Savela A, Vincent R, Kogevinas M. (2000) Occupational exposure to carcinogens in the European Union. Occup Environ Med. 57(1):10-8. 
  20. Lan Q, Zhang L, Li G, Vermeulen R, et al. (2004) Hematotoxicity in workers exposed to low levels of benzene. Science. 306(5702):1774-6. 
  21. Lauwerys RR. Hoet P. (2001) Industrial Chemical Exposure: Guidelines for Biological Monitoring, Third Edition (Brussels, Belgium: CRC/Lewis Press) 
  22. McKinney PA, Alexander FE, Cartwright RA, Parker L. (1991) Parental occupations of children with leukaemia in west Cumbria, north Humberside, and Gateshead. British Medical Journal. 302(6778):681-7. 
  23.  Morello-Frosch R, Pastor M Jr, Porras C, Sadd J. (2002) Environmental justice and regional inequality in southern California: implications for future research. Environmental Health Perspectives. 110 (Suppl 2):149-54.
  24. National Center for Environmental Assessment (NCEA). (1998) Carcinogenic Effects of Benzene: An Update. Office of Research and Development. (Washington, D.C.: U.S. Environmental Protection Agency) April. 
  25. National Toxicology Program (NTP) (1998) Eighth report on carcinogens 1998 Summary. U.S. Public Health Service, (Atlanta, GA: U.S. Department of Health and Human Services). 
  26. National Institute for Occupational Safety and Health (NIOSH) (2003) NIOSH Pocket Guide to Chemical Hazards (JJ. Keller and Associates).
  27. National Toxicology Program (NTP) (2005) Eleventh report on carcinogens. U.S. Public Health Service, (Atlanta, GA: U.S. Department of Health and Human Services). 
  28. Occupational Safety and Health Administration (OSHA) (1987). Occupational exposure to benzene. Final Rule. Federal Register. 1987;52:34460-34578. 
  29. Perlin SA, Wong D, Sexton K. (2001) Residential proximity to industrial sources of air pollution: interrelationships among race, poverty, and age. J Air Waste Manag Assoc. 51(3):406-21.
  30. Public Law 91-596, 91st Congress S. 2193.
  31. Qu YR. A cross-sectional study of health status and the development of their offspring among woman workers exposed to hazards at factories in Dalian. (1990) Zhonghua Yu Fang Yi Xue Za Zhi. 24(5):268-70.
  32. Rinsky RA, Smith AB, Hornung R, et al. (1987) Benzene and leukemia: an epidemiological risk assessment. New England Journal of Medicine. 316:1044-50. 
  33. Shu XO, Stewart P, Wen WQ, Han D, et al. (1999) Parental occupational exposure to hydrocarbons and risk of acute lymphocytic leukemia in offspring. Cancer Epidemiology Biomarkers and Prevention. 8(9):783-91.
  34. Shu XO, Gao YT, Brinton LA, Linet MS, et al. (1988) A population-based case-control study of childhood leukemia in Shanghai. Cancer. 62(3):635-44. 
  35. Smith MT. Overview of benzene-induced aplastic anaemia. Eur J Haematol Suppl. 1996;60:107-10. 
  36. State Of California Environmental Protection Agency, Office Of Environmental Health Hazard Assessment (2005) Safe Drinking Water And Toxic Enforcement Act Of 1986. Chemicals Known To The State To Cause Cancer Or Reproductive Toxicity
  37. May 27, 2005. Source: http://www.oehha.ca.gov/prop65/prop65_list/files/P65single052705.pdf.
  38. Toxics Release Inventory (2003) Data contained in the Toxics Chemical Release Inventory (TRI). http://www.epa.gov/triexplorer. Data accessed June 2005.
  39.  Wennborg H, Magnusson LL, Bonde JP, Olsen J. (2005) Congenital malformations related to maternal exposure to specific agents in biomedical research laboratories.
  40. J Occup Environ Med. Jan;47(1):11-9. 

Back to Top