Benzene

Benzene

Benzene Profile

INDUSTRIAL CHEMICALS  KNOWN CARCINOGEN (IARC 1)

CAS No. 71-43-2
IARC Monograph Vol. 29, Suppl. 7, 1987 (Group 1)
IARC Monograph Vol. 100F, 2012 (Group 1)
IARC Monograph Vol. 120, 2018 (Group 1)

Benzene Profile

QUICK SUMMARY

  • A naturally occurring substance in crude oil; also produced from the incomplete combustion of organic materials
  • Associated cancer: Acute non-lymphocytic leukemia
  • Most important route of exposure: Inhalation; skin contact
  • Uses: As a raw material to produce other chemicals such as styrene and acetone, as well as synthetic fibres
  • Occupational exposures: Approx. 360,000 Canadians are exposed at work, often via motor vehicle exhaust
  • Environmental exposures: Primarily in indoor air via a number of sources including glues, paints, and combustion sources (ex. fireplaces)
  • Fast fact: Benzene is considered a ‘non-threshold toxicant’, where adverse health effects may occur at any exposure level.

General Information

Benzene, an aromatic hydrocarbon, is a clear, usually colourless liquid with a gasoline-like odour.[1] Benzene occurs naturally as a constituent of crude oil. It has been synthesized from coal since 1849 and from petroleum sources since 1941.[1] Trace amounts of benzene are produced from the incomplete combustion of organic materials.[2] Benzene may also be referred to as benzol or coal naphtha.[3] There are numerous other synonyms and product names; see the Hazardous Substances Data Bank (HSDB) for more information.[3]

Benzene has been classified by the International Agency for Research on Cancer (IARC) as Group 1, carcinogenic to humans.[1,4] The 2017 review by IARC reaffirmed this classification, citing sufficient evidence of human carcinogenicity for acute non-lymphocytic leukemia/acute myeloid leukemia and limited evidence of carcinogenicity for chronic lymphocytic leukemiamultiple myeloma, and non-Hodgkin lymphoma. Positive associations were also observed for chronic myeloid leukemia and lung cancer.[4]

Although the hematopoietic system is the main target for benzene toxicity, the immune, lymph and nervous systems are also adversely affected by exposure.[5] Short-term exposure can cause drowsiness, headaches, and unconsciousness. The effects of long-term exposure include anaemia, neuropathies, and memory loss.[5] Benzene is also a skin irritant.[5]

Regulations and Guidelines

Occupational exposure limits (OEL) [6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]

Canadian JurisdictionsOEL (ppm)
Canada Labour Code0.5 [sk]
2.5 [stel]
AB, BC, MB, NB, NS, NL, ON, PE0.5 [sk]
2.5 [stel]
QC1 [em]
5 [stel]
YT10 [c]
SK, NU, NTALARA (no limit listed)
Other JurisdictionOEL (ppm)
ACGIH 2020 TLV0.5 [sk]
2.5 [stel]
ppm = parts per million
sk = easily absorbed through the skin
stel = short term exposure limit (15 min. maximum)
em = exposure must be reduced to the minimum
c = ceiling (not to be exceeded at any time)
ALARA = as low as reasonably achievable
ACGIH = American Conference of Governmental Industrial Hygienists
TLV = threshold limit value

Canadian environmental guidelines and standards*

JurisdictionLimitYear
Drinking Water Guidelines (Canada, BC, MB) and Standards (SK)0.005 mg/L2009-2020
[21,22,23,24]
Ontario Drinking Water Quality Standards0.001 mg/L2016[25]
Quebec’s Drinking Water StandardsMAC: 0.5 µg/L2014[26]
Government of Canada’s residential indoor air quality guidelinesALARA2013[27]
Alberta Ambient Air Quality Objectives1 hour: 30 µg/m3
Annual: 3 µg/m3
2017[28]
Ontario Ambient Air Quality Criteria24 hour: 2.3 µg/m3
Annual: 0.45 µg/m3
2016[29]
Ontario’s Air Pollution – Local Air Quality regulation standardsAnnual: 0.45 µg/m3; Prohibited discharge into the air if the concentration of benzene exceeds the standard2020[30]
Quebec’s Clean Air Regulation24 hour limit: 10 µg/m3; Prohibited discharge into the air if the concentration of benzene exceeds the standard2011[31]
BC’s Contaminated Sites Regulation, BC Reg 375/96Sets soil standards for the protection of human health:
Agricultural and low density residential sites: 150 μg/g
Urban park and high density residential sites: 350 μg/g
Commercial sites: 1,000 μg/g
Industrial sites: 6,500 μg/g

 

Drinking water: 5 μg/L

Sets vapour standards (for vapours derived from soil, sediment, or water) for the protection of human health:
Agricultural, urban park, residential use standard: 1.5 μg/m3
Commercial use standard: 4 μg/m3
Industrial use standard: 10 μg/m3
Parkade use standard: 10 μg/m3

2017[32]
Cosmetic HotlistNot Permitted2011[33]
*Standards are legislated and legally enforceable, while guidelines (including Ontario ambient air quality criteria) describe concentrations of contaminants in the environment (e.g. air, water) that are protective against adverse health, environmental, or aesthetic (e.g. odour) effects
MAC = maximum allowable concentration
ALARA = as low as reasonable achievable

Canadian agencies/organizations

AgencyDesignation/PositionYear
Health CanadaDSL – low priority substance (already risk managed)2006[34]
CEPASchedule 1, paragraph ‘c’2011[35]
National Classification System for Contaminated SitesRank = “High hazard”, potential human carcinogen2008[36]
Benzene in Gasoline Regulations1.0% max. benzene (by volume) in supplied gasoline
(Exceptions: aircraft use, vehicle competitions, scientific research)
2011[37]
Environment Canada’s National Pollutant Release InventoryReportable to NPRI if released at quantities greater than 1 tonne of 10-tonne total VOC air release or if manufactured, processed, or otherwise used at quantities greater than 10 tonnes2016[38]
DSL = domestic substance list
CEPA = Canadian Environmental Protection Act

Benzene was not included in other Canadian government guidelines, standards, or chemical listings reviewed.

Main Uses

Benzene is used primarily as a raw material to produce chemicals including: ethylbenzene, for styrene; cumene, for phenol and acetone; and cyclohexane, for nylon and synthetic fibres.[1,5]

Benzene was formerly added to gasoline as an octane enhancer and anti-knock agent (along with toluene and xylene).[2] Benzene is generally no longer used as a gasoline additive in Canada, but it does occur naturally in crude oil and gasoline.[39] Benzene has also been used to manufacture rubbers, lubricants, dyes, detergents, drugs, and pesticides.[5]

Canadian Production and Trade

Production and trade

ActivityQuantityYear

Canadian production

609,755 t

2020[40]

Export

112,686 t (of ‘benzene’)

2021[41]

Import

18,374 t (of ‘benzene’)

2021[41]

t = tonne

Environmental Exposures Overview

CAREX Canada estimates that the primary source of environmental exposure to benzene is indoor air. Benzene is emitted by a number of indoor sources, including glues, paints, furniture wax, and some detergents.[42] Combustion sources such as fireplaces, gas furnaces, cigarette smoke, and vehicles in attached garages may also contribute to indoor concentrations of benzene.[43] Having an attached garage can lead to increased exposure since benzene can more readily enter the house.[44] For example, in Canada, benzene levels are three times higher in homes with attached garages compared to those with detached or no garages. The presence of benzene is attributable to engine exhaust, as well as to the evaporation of benzene from gasoline.[44] A recent survey of homes across Canada found indoor concentrations of benzene ranging from 0.10 to 15.19 µg/m3, with average concentrations of 1.93 µg/m3.[45] CAREX Canada’s environmental estimates indicate that benzene levels in indoor and outdoor air may be sources of elevated cancer risk (high data quality).

Outdoor concentrations of benzene are generally lower than indoor concentrations.[46] Major sources of benzene in outdoor air include vehicle combustion of gasoline and diesel fuels, residential fuel combustion, iron and steel production, chemical manufacturing, as well as petroleum and coal products manufacturing.[2,42] Natural sources of benzene in the environment include forest fires, volcanos, petroleum seepage, and emissions from vegetation.[42]

Ambient air benzene levels in different locations in Canada have been monitored since 1989 by the National Air Pollution Surveillance (NAPS) network. A 2012 NAPS update indicated that the concentrations of benzene at 18 urban sites decreased by 74% between 1994 and 2009.[47]

Low levels of benzene are found in some soft drinks and a number of other foods and beverages.[48,49] Benzene contamination in soils and groundwater may also arise from oil and gas spills, underground storage tank leaks, and seepage from waste disposal sites.[3] CAREX Canada’s environmental estimates indicate that benzene levels in food and beverages may be sources of elevated cancer risk (very low data quality), although not in drinking water (moderate data quality).

Searches of Environment Canada’s National Pollutant Release Inventory (NPRI) and the US Consumer Product Information Database yielded the following results on current potential for exposure to benzene in Canada:

NPRI and US Consumer Product Information Database

NPRI 2015[50]
Substance name: ‘Benzene’
CategoryQuantityIndustry
Released into Environment736 tOil and gas extraction,
basic chemical manufacturing,
iron and steel mills and ferro-alloy manufacturing,
petroleum and coal product manufacturing
(234 facilities)
Disposed of1,065 t
Sent to off-site recycling1,055 t
US Consumer Products 2016[51]
Search Term# ProductsProduct Type
‘Benzene’17adhesives (3), interior paints (2), wood finish (1),
adhesive remover (1), pet care lotion (1), sealant (1),
auto part cleaner/degreaser (5), motor oil (3)
t = tonne

For more information, see the environmental exposure estimate for benzene.

Occupational Exposures Overview

The most important route of occupational exposure to benzene is inhalation, but dermal exposure can also occur.[1,5]

CAREX Canada estimates that approximately 360,000 Canadian workers are exposed to benzene; most exposures occur in the low exposure category. Many workers are exposed to benzene via inhalation of motor vehicle exhaust.

Industries where the largest numbers of workers are exposed include automotive repair and maintenance, public administration (where firefighters are included), and taxi and limo service. According to the US Department of Labour, benzene exposure is also likely during petrochemical production, petroleum refining, coke and coal chemical manufacturing, tire manufacturing, and storage or transport of benzene and petroleum products containing benzene.[52]

Occupations at risk of benzene exposure include automotive service technicians and mechanics, delivery and courier drivers, taxi and limousine drivers, and firefighters. Other occupations such as steel workers, printers, rubber workers, shoemakers, laboratory technicians, and gas station employees were also identified as exposed.[52]

According to the Burden of Occupational Cancer in Canada project, occupational exposure to benzene leads to approximately 20 leukemia cancers, and less than 5 possible multiple myeloma cancers each year in Canada, based on past exposures (1961-2001).[53,54] This amounts to 0.5% of all leukemia and 0.2% of all multiple myeloma cancers diagnosed annually. Most benzene-related cancers occur among workers in the manufacturing, transportation and warehousing, and trade sectors.[54]

For more information, see the occupational exposure estimate for benzene.

Sources

Photo: Wikimedia Commons, Ilya Plekhanov

1. National Toxicology Program (NTP). 14th report on carcinogens for Benzene (2016) (PDF)
3. US National Library of Medicine. PubChem (Search term: ‘Benzene’)
4. International Agency for Research on Cancer (IARC). Monographs on the Evaluation of Carcinogenic Risks to Humans Volume 120. Benzene (2018)
5. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological Profile for Benzene (2007) (PDF)
9. The Canadian Legal Information Institute (CanLII) Manitoba Regulation 217/2006 Workplace Safety and Health Regulation (2022)
11. Government of Newfoundland and Labrador. Regulation 5,12 Occupational Health and Safety Regulations (2018)
12. Government of the Northwest Territories. Occupational Health and Safety Regulations, R-039-2015 (2020) (PDF)
14. The Canadian Legal Information Institute (CanLII). Government of Nunavut’s Occupational Health and Safety Regulations, Nu Reg 003-2016 (2010)
16. Government of Prince Edward Island. Occupational Health and Safety Act Regulations Chapter 0-1 (2013) (PDF)
18. The Canadian Legal Information Institute (CanLII) The Occupational Health and Safety Regulations, 1996 (2022)
19. The Canadian Legal Information Institute (CanLII). Yukon’s Occupational Health Regulations, O.I.C. 1986/164 (2020) (PDF)
20. Occupational Safety and Health Administration (OSHA). Annotated PELs (2020)
22. Government of British Columbia. Source Drinking Water Quality Guidelines (2020) (PDF)
24. Government of Manitoba, Manitoba Water Stewardship. Manitoba Water Quality Standards, Objectives, and Guidelines (2011) (PDF)
25. The Canadian Legal Information Institute (CanLII). Ontario Drinking Water Quality Standards, O Reg 169/03 (2020)
26. The Canadian Legal Information Institute (CanLII). Regulation respecting the quality of drinking water, CQLR c Q-2, r 40 (2022)
27. Government of Canada. Residential indoor air quality guidelines (2020)
28. Alberta Environment and Parks. Ambient Air Quality Objectives (2019)
29. Ontario Ministry of the Environment and Climate Change. Ontario’s Ambient Air Quality Criteria (2019)
31. Government of Quebec. Clean Air Regulation, Q-2, r. 4.1 (2020)
32. Government of British Columbia. Contaminated Sites Regulation B.C. Reg. 375/96 (2019)
33. Health Canada. Cosmetic Ingredient Hotlist (2019)
34. Health Canada. Prioritization of the DSL (2006)
35. Environment and Climate Change Canada. CEPA List of Toxic Substances (2020)
36. Canadian Council of Ministers of the Environment (CCME). National Classification System for Contaminated Sites (2008) (PDF)
37. Environment Canada. Benzene in Gasoline Regulations (1997) (PDF)
41. International Trade Centre. TradeMap (Free subscription required)
43. Héroux ME, Clark N, Van Ryswyk K, Mallick R, Gilbert NL, Harrison I, Rispler K, Wang D, Anastassopoulos A, Guay M, MacNeill M, Wheeler AJ. “Predictors of Indoor Air Concentrations in Smoking and Non-Smoking Residences.” Intern Journ of Environ Res and Public Health 2010;7:3080-3099. (PDF)
46. Health Canada. Benzene in Indoor Air (2013) (PDF)
47. Canadian Council of Ministers of the Environment (CCME). Canada-wide standard for benzene: 2010 final report (2012) (PDF)
48. Nyman PJ, Diachenko GW, Perfetti GA, McNeal TP, Hiatt MH, Morehous KM. “Survey Results of Benzene in Soft Drinks and Other Beverages by Headspace Gas Chromatography/Mass Spectrometry.” J Agric Food Chem 2008;56(2):571-576.
49. Cao X-L, Sparling M, Dabeka R. “Occurrence of 13 volatile organic compounds in foods from the Canadian total diet study.”Food Addit Contam Part A 2016;33(2):373-382
50. Environment and Climate Change Canada. National Pollutant Release Inventory (NPRI) data search (Substance name: ‘(71-43-2) Benzene’)
51. Consumer Product Information Database (CPID).What’s in it? (2022) (Search term: ‘Benzene’)
52. Occupational Safety and Health Administration (OSHA). Benzene: Exposure Evaluation
53. Labrèche F, Kim J, Song C, Pahwa M, Calvin BG, Arrandale VH, McLeod CB, Peters CE, Lavoué J, Davies HW, Nicol AM. “The current burden of cancer attributable to occupational exposures in Canada.” Prev Med 2019;122:128-39.
54. Occupational Cancer Research Centre. Other burden results. (2017)

 

Subscribe to our newsletters

The CAREX Canada team offers two regular newsletters: the biannual e-Bulletin summarizing information on upcoming webinars, new publications, and updates to estimates and tools; and the monthly Carcinogens in the News, a digest of media articles, government reports, and academic literature related to the carcinogens we’ve classified as important for surveillance in Canada. Sign up for one or both of these newsletters below.

CAREX Canada

School of Population and Public Health

University of British Columbia
Vancouver Campus
370A - 2206 East Mall
Vancouver, BC  V6T 1Z3
CANADA

© 2025 CAREX Canada
Simon Fraser University

As a national organization, our work extends across borders into many Indigenous lands throughout Canada. We gratefully acknowledge that our host institution, the University of British Columbia Point Grey campus, is located on the traditional, ancestral, and unceded territories of the xʷməθkʷəy̓əm (Musqueam) people.

Benzene – Environmental Exposures

Benzene – Environmental Exposures

Benzene Environmental Exposures

Benzene Environmental Exposures

Overview

CAREX Canada estimates that the primary source of environmental exposure to benzene is indoor air. Benzene is emitted by a number of indoor sources, including glues, paints, furniture wax, and some detergents.[1] Combustion sources such as fireplaces, gas furnaces, cigarette smoke, and vehicles in attached garages may also contribute to indoor concentrations of benzene.[2]

 
READ MORE...

Having an attached garage can lead to increased exposure since benzene can more readily enter the house.[3] For example, in Canada, benzene levels are three times higher in homes with attached garages compared to those with detached or no garages.

The presence of benzene is attributable to engine exhaust, as well as to the evaporation of benzene from gasoline.[3] A recent survey of homes across Canada found indoor concentrations of benzene ranging from 0.10 to 15.19 µg/m3, with average concentrations of 1.93 µg/m3.[4] CAREX Canada’s environmental estimates indicate that benzene levels in indoor and outdoor air may be sources of elevated cancer risk (high data quality).

Outdoor concentrations of benzene are generally lower than indoor concentrations.[5] Major sources of benzene in outdoor air include vehicle combustion of gasoline and diesel fuels, residential fuel combustion, iron and steel production, chemical manufacturing, as well as petroleum and coal products manufacturing.[1,6] Natural sources of benzene in the environment include forest fires, volcanos, petroleum seepage, and emissions from vegetation.[1]

Ambient air benzene levels in different locations in Canada have been monitored since 1989 by the National Air Pollution Surveillance (NAPS) network. A 2012 NAPS update indicated that the concentrations of benzene at 18 urban sites decreased by 74% between 1994 and 2009.[6]

Low levels of benzene are found in some soft drinks and a number of other foods and beverages.[7,8] Benzene contamination in soils and groundwater may also arise from oil and gas spills, underground storage tank leaks, and seepage from waste disposal sites.[9] CAREX Canada’s environmental estimates indicate that benzene levels in food and beverages may be sources of elevated cancer risk (very low data quality), although not in drinking water (moderate data quality).

Searches of Environment Canada’s National Pollutant Release Inventory (NPRI) and the US Household Products Database yielded the following results on current potential for exposure to benzene in Canada:

NPRI and US Household Products Database

NPRI 2015[10]
Substance name: ‘Benzene’
CategoryQuantityIndustry
Released into Environment736 tOil and gas extraction,
basic chemical manufacturing,
iron and steel mills and ferro-alloy manufacturing,
petroleum and coal product manufacturing
(234 facilities)
Disposed of1,065 t
Sent to off-site recycling1,055 t
t = tonne
US Household Products 2016[11]
Search Term# ProductsProduct Type
‘Benzene’17adhesives (3), interior paints (2), wood finish (1),
adhesive remover (1), pet care lotion (1), sealant (1),
auto part cleaner/degreaser (5), motor oil (3)

Mapping

This map shows predicted levels of benzene in outdoor air at residential locations by health region in Canada as of 2011. The average (median) concentration of benzene within the health regions measured in outdoor air for 2011 was 0.608 µg/m3, but concentrations of benzene can be higher or lower than average in many locations. Concentrations should be compared to the applicable jurisdictional guidelines and standards for ambient air quality based on chronic, carcinogenic effects (or non-carcinogenic effects, if cancer is not the point of interest).

*Measured at the National Air Pollution Surveillance (NAPS) monitors in 2011

Cancer risk estimates

Potential lifetime excess cancer risk (LECR) is an indicator of Canadians’ exposure to known or suspected carcinogens in the environment. When potential LECR is more than 1 per million in a single pathway, a more detailed risk assessment may be useful for confirming the need to reduce individual exposure. If measured levels of benzene in relevant exposure pathways (outdoor air, indoor air, drinking water, and food and beverages) decrease, the risk will also decrease.

Potential LECR is calculated by multiplying lifetime average daily intake (the amount inhaled or ingested) by a cancer potency factor or unit risk factor. More than one cancer potency factor may be available, because agencies interpret the underlying health studies differently, or use a more precautionary approach. Our results use cancer potency factors from Health Canada, the US Environmental Protection Agency (US EPA), and/or the California Office of Environmental Health Hazard Assessment (OEHHA).

The calculated lifetime daily intake and LECR results for benzene are provided in the tables below. For more information on supporting data and sources, click on the Methods and Data tab below.

Calculated lifetime daily intake

Lifetime excess cancer risk (per million people)

*LECR based on average intake x cancer potency factor from each agency

Compare substances: Canadian potential lifetime excess cancer risk, 2011

The data in this table are based on average intake and Health Canada’s cancer potency factor, assuming no change in measured levels. When Health Canada values are not available, United States Environmental Protection Agency values are used.
Click the second tab to view LECR data. 

**Exposure not applicable: For indicated pathways, substance not present, not carcinogenic, or exposure is negligible
**Gap in data: No cancer potency factor or unit risk factor, or no data available
IARC Group 1 = Carcinogenic to humans, IARC Group 2A = Probably carcinogenic to humans, IARC Group 2B = Possibly carcinogenic to humans

NOTE: Chromium (hexavalent) estimates assume that 5% of total chromium measured in outdoor air is hexavalent and 8% total chromium measured in indoor dust is hexavalent.

Potential LECR assumes exposure occurs at the same level, 24 hours per day, for 70 years. This is rarely true for any single individual, but using a standard set of assumptions allows us to provide a relative ranking for known and suspected carcinogens across different exposure routes. While ongoing research continually provides new evidence about cancer potency and whether there is a safe threshold of exposure, our approach assumes there are no safe exposure levels.

Methods and Data

Our Environmental Approach page outlines the general approach used to calculate lifetime excess cancer risk estimates and includes documentation on our mapping methods.

Data sources and data quality for benzene can be found in the PDF below.

Supplemental data – Benzene [PDF]

Sources

2. Héroux ME, Clark N, Van Ryswyk K, Mallick R, Gilbert NL, Harrison I, Rispler K, Wang D, Anastassopoulos A, Guay M, MacNeill M, Wheeler AJ. “Predictors of Indoor Air Concentrations in Smoking and Non-Smoking Residences.” Intern Journ of Environ Res and Public Health 2010;7:3080-3099. (PDF)
5. Health Canada. Benzene in Indoor Air (2013) (PDF)
7. Canadian Council of Ministers of the Environment (CCME). Canada-wide standard for benzene: 2010 final report (2012) (PDF)
8. Nyman PJ, Diachenko GW, Perfetti GA, McNeal TP, Hiatt MH, Morehous KM. “Survey Results of Benzene in Soft Drinks and Other Beverages by Headspace Gas Chromatography/Mass Spectrometry.” J Agric Food Chem 2008;56(2):571-576.
9. Cao X-L, Sparling M, Dabeka R. “Occurrence of 13 volatile organic compounds in foods from the Canadian total diet study.”Food Addit Contam Part A 2016;33(2):373-382.
10. Environment and Climate Change Canada. National Pollutant Release Inventory (NPRI) data search (Substance name: ‘(71-43-2) Benzene’)
11. Consumer Product Information Database (CPID).What’s in it? (2022) (Search term: ‘Benzene’)
        

Subscribe to our newsletters

The CAREX Canada team offers two regular newsletters: the biannual e-Bulletin summarizing information on upcoming webinars, new publications, and updates to estimates and tools; and the monthly Carcinogens in the News, a digest of media articles, government reports, and academic literature related to the carcinogens we’ve classified as important for surveillance in Canada. Sign up for one or both of these newsletters below.

CAREX Canada

School of Population and Public Health

University of British Columbia
Vancouver Campus
370A - 2206 East Mall
Vancouver, BC  V6T 1Z3
CANADA

© 2025 CAREX Canada
Simon Fraser University

As a national organization, our work extends across borders into many Indigenous lands throughout Canada. We gratefully acknowledge that our host institution, the University of British Columbia Point Grey campus, is located on the traditional, ancestral, and unceded territories of the xʷməθkʷəy̓əm (Musqueam) people.

Benzene – Occupational Exposures

Benzene Occupational Exposures

Benzene Occupational Exposures

Overview

The most important route of occupational exposure to benzene is inhalation, but dermal exposure can also occur.[1,2] Many workers are exposed to benzene via inhalation of motor vehicle exhaust. CAREX Canada estimates that approximately 360,000 Canadian workers are exposed to benzene; most exposures occur in the low exposure category.

READ MORE...

Industries where the largest numbers of workers are exposed include automotive repair and maintenance, public administration (where firefighters are included), and taxi and limo service. According to the US Department of Labour, benzene exposure is also likely during petrochemical production, petroleum refining, coke and coal chemical manufacturing, tire manufacturing, and storage or transport of benzene and petroleum products containing benzene.[3]

Occupations at risk of benzene exposure include automotive service technicians and mechanics, delivery and courier drivers, taxi and limousine drivers, and firefighters. Other occupations such as steel workers, printers, rubber workers, shoemakers, laboratory technicians, and gas station employees were also identified as exposed.[3]

According to the Burden of Occupational Cancer in Canada project, occupational exposure to benzene leads to approximately 20 leukemia cases, and less than 5 possible multiple myeloma cancers each year in Canada, based on past exposures (1961-2001).[4,5] This amounts to 0.5% of all leukemia and 0.2% of all multiple myeloma cancers diagnosed annually. Most benzene-related cancers occur among workers in the manufacturing, transportation and warehousing, and trade sectors.[5]

Prevalence Estimate

Results show that 360,000 Canadians (approximately 2% of the working population) are exposed to benzene in their workplaces; 89% of these workers are male.

Industries with the greatest numbers of exposed workers include automotive repair and maintenance, public administration (where firefighters are included), and taxi and limo service. When benzene exposure is examined by occupation, automotive service technicians and mechanics are the group with the greatest number of workers exposed to benzene (62,000 workers exposed). Other jobs with high numbers of workers exposed include delivery and courier drivers (46,000 workers exposed), taxi and limousine drivers (46,000 workers exposed), and firefighters (32,000 workers exposed). 

The number of workers exposed to benzene decreased by approximately 14,000 workers from 2006 to 2016 (a 5% decrease). This was primarily driven by decreases in the number of workers in printing and rubber manufacturing as well as newspaper related industries

Workers exposed to benzene by industry in 2016

Alberta, Nova Scotia, Manitoba and Saskatchewan have a higher proportion of workers exposed to benzene than the national average (>2.3%), and Prince Edward Island, the Yukon and Nunavut have less workers exposed to benzene than the national average (<1.7%).

Workers exposed to benzene by region in 2016

Click the second tab to view total number of workers exposed.

[

* = < 50 workers

Level of Exposure

In total, approximately 360,000 Canadians are exposed to benzene in their workplaces. The majority of workers exposed to benzene are in the low exposure category. A substantial number of benzene-exposed workers are at risk for moderate exposure, but very few are at risk of high exposure.

Workers exposed to benzene by exposure level in 2016

Level of exposure by industry

Identifying industries with either 1) workers exposed to high levels of benzene or 2) a larger number of workers exposed to benzene is important in guiding cancer prevention efforts to prioritize exposed groups and target resources most effectively.

The table below shows the number of workers exposed by industry group and level of exposure to benzene. These results highlight industries with the most number of workers, as well as industries with the highest levels of exposure. 

For example, in the transit and ground passenger transportation, which has the highest number of workers exposed, all of the workers fall into the low exposure category. However, in the printing and related support activities industry, a significant proportion (36%) of the exposed workers are in the moderate exposure category. Depending on the goals of a prevention campaign, exposure reduction in the large industrial group might be a useful strategy, or reducing exposure to those at highest risk of exposure could be seen as a priority.

Workers exposed to benzene by exposure level and industry in 2016

*Numbers may not add up due to rounding

 

Methods and Data

Our Occupational Approach page outlines the general approach used to calculate prevalence and exposure level estimates for workplace exposures.

Data Sources

Data used in developing the occupational estimates for benzene were collected from several sources:

  1. The Canadian Workplace Exposure Database (CWED) contains over 1,500 measurements for benzene exposure. These measurements were collected during the years 1981 to 2004 in Ontario and British Columbia workplaces.
  2. Canadian and US scientific peer reviewed publications that addressed benzene exposure in Canada and the United States.
  3. Grey literature including technical reports from governments and international bodies.

Prevalence Estimate Method

CAREX defines exposure to benzene as inhalation exposure at work to levels above those encountered in the general environment.

To determine the number of workers potentially exposed to benzene at work, CAREX occupational exposure experts used methods previously established in other peer-reviewed CAREX projects in Europe. A series of steps were taken to assign exposure proportions to occupations and industries at risk of exposure to benzene.

  1. Occupations and industries at risk of possible exposure to benzene were identified using any combination of data sources described above.
  2. The total number of workers in each identified occupation and industry intersection was obtained from Statistics Canada 2016 census data.
  3. A percentage of workers exposed was assigned to that occupation and industry intersection. Percentages were determined by consultation with existing evidence in the data sources, previously established methods from the Europe CAREX estimates and the expert judgement of CAREX occupational hygienists.
  4. The number of workers in the identified group is multiplied by the assigned percentage to calculate the prevalence estimate of workers exposed to benzene.

 

Exposure Level Method

CAREX uses available workplace exposure measurements in the CWED to create exposure level categories by industry and occupation. For benzene, these categories are:

Category 1: Low Exposure

A group of workers (people in the same job category and industry) is put in this exposure category for one of two reasons:

  1. The are no valid measurements, but a hygienist identified this group as typically exposed during literature and other reviews;
  2. There are valid exposure measurements in the CWED and a hygienist review determined that exposure is plausible; AND EITHER:
    1. There are less than 10 samples available in the CWED, OR
    2. There are ≥10 measurements available but they do not meet the criteria for Moderate Exposure.

Category 2/3: Moderate to High Exposure

A group of workers is put in this exposure category if:

  1. There are at least 25 individual samples in the CWED, AND
  2. 20% or more samples have a value higher than 0.25 ppm (which is ½ of the current occupational exposure limit for benzene).

OR

  1. There are at least 10 individual samples in the CWED, AND
  2. 20% or more samples have a value higher than 0.5 ppm (which is the current occupational exposure limit for benzene).

For benzene, the moderate and high exposure categories were combined due to very few workers exposed above 0.5 ppm.

Sources

1. National Toxicology Program (NTP). 14th report on carcinogens for Benzene (2016) (PDF)
2. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological Profile for Benzene (2007) (PDF)
3. Occupational Safety and Health Administration (OSHA). Benzene: Exposure Evaluation
4. Labrèche F, Kim J, Song C, Pahwa M, Calvin BG, Arrandale VH, McLeod CB, Peters CE, Lavoué J, Davies HW, Nicol AM. “The current burden of cancer attributable to occupational exposures in Canada.” Prev Med 2019;122:128-39.
5. Occupational Cancer Research Centre. Other burden results. (2017)

Subscribe to our newsletters

The CAREX Canada team offers two regular newsletters: the biannual e-Bulletin summarizing information on upcoming webinars, new publications, and updates to estimates and tools; and the monthly Carcinogens in the News, a digest of media articles, government reports, and academic literature related to the carcinogens we’ve classified as important for surveillance in Canada. Sign up for one or both of these newsletters below.

CAREX Canada

School of Population and Public Health

University of British Columbia
Vancouver Campus
370A - 2206 East Mall
Vancouver, BC  V6T 1Z3
CANADA

© 2025 CAREX Canada
Simon Fraser University

As a national organization, our work extends across borders into many Indigenous lands throughout Canada. We gratefully acknowledge that our host institution, the University of British Columbia Point Grey campus, is located on the traditional, ancestral, and unceded territories of the xʷməθkʷəy̓əm (Musqueam) people.

Benzene – Resources

Benzene Resources

Package summaries

Tools

Special topics pages

Publications

Videos

Other

Exposure Reduction

Our team has performed a detailed scan of exposure control resources and assembled a compilation of key publications and resources. These are organized by type of exposure (environmental or occupational) and by specificity (general or carcinogen-specific). Please visit our Exposure Reduction Resources page to view.

We also recommend exploring the Prevention Policies Directory, a freely-accessible online tool offering information on policies related to cancer and chronic disease prevention. Providing summaries of the policies and direct access to the policy documents, the Directory allows users to search by carcinogen, risk factor, jurisdiction, geographical location, and document type. For questions about this resource, please contact a member of the Prevention Team at the Canadian Partnership Against Cancer at [email protected].

Subscribe to our newsletters

The CAREX Canada team offers two regular newsletters: the biannual e-Bulletin summarizing information on upcoming webinars, new publications, and updates to estimates and tools; and the monthly Carcinogens in the News, a digest of media articles, government reports, and academic literature related to the carcinogens we’ve classified as important for surveillance in Canada. Sign up for one or both of these newsletters below.

CAREX Canada

School of Population and Public Health

University of British Columbia
Vancouver Campus
370A - 2206 East Mall
Vancouver, BC  V6T 1Z3
CANADA

© 2025 CAREX Canada
Simon Fraser University

As a national organization, our work extends across borders into many Indigenous lands throughout Canada. We gratefully acknowledge that our host institution, the University of British Columbia Point Grey campus, is located on the traditional, ancestral, and unceded territories of the xʷməθkʷəy̓əm (Musqueam) people.

Beryllium

Beryllium

Beryllium Profile

METALS  KNOWN CARCINOGEN (IARC 1)

CAS No. 7440-41-7
IARC Monograph Vol. 58, 1993 (Group 1)
IARC Monograph Vol 100C, 2012 (Group 1)

Beryllium Profile

General Information

Beryllium (chemical symbol Be) is a silver-gray coloured metallic element that occurs naturally at low concentrations in the earth’s crust.[1,2] Two kinds of beryllium minerals are mined commercially, bertrandite and beryl (of which emeralds are a type).[3]

Beryllium and its compounds have been classified by the International Agency for Research on Cancer (IARC) as Group 1 agents, carcinogenic to humans, with a well-established link to lung cancer.[2,4] The 2012 review of Class 1 carcinogens by IARC reaffirmed this classification.[5]

Beryllium is highly sensitizing, even at very low levels of exposure. Exposure can cause acute beryllium disease (ABD) and chronic beryllium disease (CBD).[3] ABD is a condition that resembles pneumonia. It can occur after short-term, high levels of exposure to beryllium (>1 mg/m3).[3] CBD is an inflammatory lung disease that causes fibrosis. The relationship between sensitization to beryllium and subsequent disease development is not fully understood. In addition, there is no known lower limit for beryllium sensitization and development of CBD.[3] Dermal contact can also lead to an allergic response.[3]

Regulations and Guidelines

Occupational exposure limits (OEL) [6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]

Canadian JurisdictionsSubstanceOEL (mg/m3)
Canada Labour CodeBeryllium and compounds, as Be0.00005 [i, sk, dsen, rsen]
AB, NB, NT. NU, SKBeryllium and compounds, as Be0.002
0.01 [stel]
BC, MB, NB, NL, NS, PEBeryllium and compounds, as Be0.00005 [i, sk, dsen, rsen]
ONBeryllium and compounds, as Be0.00005 [i] [sk, for soluble compounds only]
QCBeryllium and compounds, as Be0.00015 [sen, em]
YTBeryllium0.002
Other JurisdictionsSubstanceOEL
ACGIH 2020 TLVBeryllium and compounds, as Be0.00005 [i, sk, sen]
mg/m3 = milligrams per cubic meter
sk = easily absorbed through the skin
dsen = dermal sensitization
rsen = respiratory sensitization
sen = potential for sensitization
i = inhalable fraction
stel = short term exposure limit (15 min. maximum)
em = exposure must be reduced to the minimum
ACGIH = American Conference of Governmental Industrial Hygienists
TLV = threshold limit value

Canadian environmental guidelines and standards*

JurisdictionLimitYear
Cosmetic Ingredient HotlistNot Permitted2015[21]
Ontario Ambient Air Quality Criteria24-hour: 0.01 µg/m3 (for beryllium and compounds)2016[22]
Ontario’s Air Pollution – Local Air Quality Regulation24-hour standard: 0.01 µg/m3; Prohibited discharge into the air if the concentration of beryllium exceeds the standard2020[23]
Quebec’s Clean Air Regulation1 year limit: 0.0004 µg/m3; Prohibited discharge into the air if the concentration of beryllium exceeds the standard2011[24]
BC’s Contaminated Sites Regulation, BC Reg 375/96Sets soil standards for the protection of human health:
Agricultural and low density residential sites: 85 μg/g
Urban park and high density residential sites: 150 μg/g
Commercial sites: 500 μg/g
Industrial sites: 15,000 μg/g

 

Drinking water: 8 µg/L

2019[25]
*Standards are legislated and legally enforceable, while guidelines (including Ontario ambient air quality criteria) describe concentrations of contaminants in the environment (e.g. air, water) that are protective against adverse health, environmental, or aesthetic (e.g. odour) effects

Canadian agencies/organizations

AgencyDesignation/PositionYear
Health CanadaDSL – high priority substance with lowest potential for exposure2006[26]
National Classification System for Contaminated SitesRank: “High hazard”2008[27]
PMRA List of formulantsList 4B: List 4B contains formulants, some of which may be toxic, for which there are sufficient data to reasonably conclude that the specific use pattern of the pest control product will not adversely affect public health and the environment.2020[28]
DSL = domestic substance list

Beryllium was not included in other Canadian government guidelines, standards, or chemical listings reviewed.

Main Uses

Beryllium metal is used in aircraft/satellite structures, x-ray transmission windows, spacecraft instrumentation, nuclear weapons, mirrors, and computer and audio components.[1] In alloys, beryllium increases strength as well as thermal and electrical conductivity,[1] making it useful in consumer goods like automobiles, computers, sports equipment (especially bike frames), and dental bridges.[3] Beryllium oxide is typically used for specialty ceramics in electrical and high-technology applications.[3]

Canadian Production and Trade

The United States exported 13 tonnes of beryllium to Canada in 2021, and remains the largest global exporter of such, exporting 170 tonnes annually.[29,30]

Production and trade

ActivityQuantityYear
Export3 t (of ‘Articles of beryllium, n.e.s.’)2021[31]
Import14 t (of ‘Articles of beryllium, n.e.s.’)2021[31]
t = tonne

Environmental Exposures Overview

Sources of environmental exposure to beryllium include burning coal[2] and fuel oil.[3] Residual beryllium left on work garments may also lead to exposures in the home.[1]

Beryllium is found at low levels geologically in Canada, mostly in northern British Columbia and southern Yukon, as well as the Northwest Territories.[32]

No household products are listed as containing Beryllium in the Consumer Product Information Database in the United States.[33,34]

Occupational Exposures Overview

Inhalation is the most important route of occupational exposure.[1] CAREX Canada estimates that approximately 3,800 Canadians are exposed to beryllium in their workplace. The largest industrial groups exposed are building equipment contractors, residential building construction, and automotive repair and maintenance.​ Other important industries where beryllium exposure occurs are non-residential building construction and medical equipment and supplies manufacturing.

The primary occupational groups exposed are construction trades helpers, electricians, welders, and dental technologists. Additional groups that may also be exposed include workers involved in beryllium alloy production, metals and related products manufacturing, nuclear reactor operation, and electric and electronic equipment production.

Although only a small number of workers are exposed to high levels worldwide, the number of workers exposed to low levels is increasing.[2] This increase is due to increased use of beryllium in the aircraft, aerospace, nuclear, and electronics industries.[2]

For more information, see the occupational exposure estimate for beryllium.

Sources

Photo: Wikimedia Commons, Theodore W. Gray

1. National Toxicology Program (NTP). 14th report on carcinogens for Beryllium and Beryllium Compounds (2016) (PDF)
2. International Agency for Research on Cancer (IARC). Monograph summary, Volume 58 (1993) (PDF)
3. Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological Profile for beryllium (2002) (PDF)
4. Henneberger PK, Goe SK, Miller WE, Doney B, Groce DW. “Industries in the United States with airborne beryllium exposure and estimates of the number of current workers potentially exposed.” J Occup Environ Hyg 2004;1(10):648-659.
5. International Agency for Research on Cancer (IARC). Monograph summary, Volume 100C (2012) (PDF)
9. The Canadian Legal Information Institute (CanLII) Manitoba Regulation 217/2006 Workplace Safety and Health Regulation (2022)
11. Government of Newfoundland and Labrador. Regulation 5,12 Occupational Health and Safety Regulations (2018)
12. Government of the Northwest Territories. Occupational Health and Safety Regulations, R-039-2015 (2020) (PDF)
14. The Canadian Legal Information Institute (CanLII). Government of Nunavut’s Occupational Health and Safety Regulations, Nu Reg 003-2016 (2010)
16. Government of Prince Edward Island. Occupational Health and Safety Act Regulations Chapter 0-1 (2013) (PDF)
18. The Canadian Legal Information Institute (CanLII) The Occupational Health and Safety Regulations, 1996 (2022)
19. The Canadian Legal Information Institute (CanLII). Yukon’s Occupational Health Regulations, O.I.C. 1986/164 (2020) (PDF)
20. Occupational Safety and Health Administration (OSHA). Annotated PELs (2020)
21. Health Canada. Cosmetic Ingredient Hotlist (2019)
22. Ontario Ministry of the Environment and Climate Change. Ontario’s Ambient Air Quality Criteria (2019)
24. Government of Quebec. Clean Air Regulation, Q-2, r. 4.1 (2020)
25. Government of British Columbia. Contaminated Sites Regulation B.C. Reg. 375/96 (2021)
27. Canadian Council of Ministers of the Environment (CCME). National Classification System for Contaminated Sites (2008) (PDF)
31. International Trade Centre. TradeMap (Free subscription required)
32. Groat, LA, Hart C, Lewis LL, Neufeld H. “Emerald and aquamarine mineralization in Canada.” Geoscience Canada, 2005;32(2):65-76.
33. Environment and Climate Change Canada. National Pollutant Release Inventory (NPRI) Facility Search (Substance name: ‘Beryllium’)
34. Consumer Product Information Database. What’s in it? (2022)

   

Other Resources

  1. Institut de recherche Robert-Sauvé en santé et en Sécurité du travail (IRSST). Speciation and characterization of beryllium dusts (2005) (PDF, French)
  2. US Geological Survey. Minerals Yearbook: Beryllium (1999) (PDF)
  3. International Programme on Chemical Safety (IPCS) INCHEM. Concise International Chemical Assessment Document 32: Beryllium and beryllium compounds (2001)

Subscribe to our newsletters

The CAREX Canada team offers two regular newsletters: the biannual e-Bulletin summarizing information on upcoming webinars, new publications, and updates to estimates and tools; and the monthly Carcinogens in the News, a digest of media articles, government reports, and academic literature related to the carcinogens we’ve classified as important for surveillance in Canada. Sign up for one or both of these newsletters below.

CAREX Canada

School of Population and Public Health

University of British Columbia
Vancouver Campus
370A - 2206 East Mall
Vancouver, BC  V6T 1Z3
CANADA

© 2025 CAREX Canada
Simon Fraser University

As a national organization, our work extends across borders into many Indigenous lands throughout Canada. We gratefully acknowledge that our host institution, the University of British Columbia Point Grey campus, is located on the traditional, ancestral, and unceded territories of the xʷməθkʷəy̓əm (Musqueam) people.