Chloroform Regulations and Guidelines
CAS No. 67-66-3 Occupational Exposure Limits (OEL)
CANAdIAN JuRISdICtIoNS oEL (ppm)
Canada Labour Code 10
BC 2 [repro]
AB, MB, NL, PE, NB, NS, YT 10
SK No limit listed
QC 5 [sk]
Wikimedia Commons Photo: Chloroform (1) othER JuRISdICtIoNS oEL (ppm)
IARC monograph Vol. 73, 1999
(Group 2B) ACGIH 2008 TLV 10
SCOEL 2 [sk]
repro = reproductive toxin
ppm = parts per million
General Information stel = short term exposure limit (15 min. maximum)
sk = easily absorbed through the skin
Chloroform is a non-flammable, colourless, volatile liquid (2). It may
also be referred to as trichloromethane or methane trichloride (3). Canadian Environmental Guidelines
Chloroform is one of a group of compounds found as by-products
of chlorination of drinking water, known as trihalomethanes. There JuRISdICtIoN LImIt
are numerous other synonyms and product names; see HSDB for
more information (4). Canadian Drinking Water For total 2007
Guidelines trihalomethanes (7)
In 1999, IARC classified chloroform as Group 2B (possibly carcinogenic (THMs)
to humans) based on evidence in experimental animals (3). Chloroform 0.1 mg/L (MAC)
is a liver and kidney carcinogen in mice and rats (3). Residential Indoor 1987
Air Quality (8)
Several epidemiological studies have suggested that exposure to
chloroform in chlorinated drinking water is associated with excess
cancers, particularly of the urinary bladder, colon and rectum (3).
Causality, however, can not be determined because of uncertainties, YEAR
including confounding by other chlorination by-products (3).
Health Canada DSL – low priority 2006
Additionally, chronic inhalation exposure to elevated levels of substance (already (9)
chloroform may cause liver and kidney damage, as well as neurological risk managed)
symptoms (5). Acute inhalation exposure to chloroform can cause
CEPA Priority Substance List 1999
dizziness, fatigue, and headache (5). Dermal contact can cause (PSL2)* (10)
irritation and damage to the skin (6).
*A 2001 assessment of chloroform concluded that the criteria for inclusion as ‘toxic’
The NTP’s 11th Report on Carcinogens classifies chloroform as under paragraph 64(B) of CEPA 1999 was not met and further measures would not
“reasonably anticipated to be a human carcinogen,” based on be pursued (11).
sufficient evidence in experimental animals (2).
CAREX Canada ranks chloroform as Group A (immediate high • Prior to World War II, chloroform was used as an anaesthetic
priority) for both the occupational and environmental settings. and in pharmaceutical preparations (5).
Prioritization was based on the carcinogenicity and other toxic • Other historical uses include the production of resins, fats,
properties of the substance, the prevalence of exposure in Canada, greases, gums, waxes, and oils, and as a chemical intermediate
and the feasibility of assessing exposure. in dye and pesticide production (11).
• In more recent years, chloroform has been used predominately Occupational Exposures
for the synthesis of other chemicals, such as hydroclorofluoro- • Inhalation is the most important route of occupational exposure (2).
carbon-22 (HCFC-22) which is used as a refrigerant (5). • Occupational exposure to chloroform may occur during its
• Chloroform is also used in the extraction and purification of some production and use as a solvent and chemical intermediate (3).
antibiotics, alkaloids, vitamins, and flavours, and as a solvent for • The main occupations exposed include workers involved in
lacquers, floor polishes, and adhesives (2). the manufacturing of chloroform or of HCFC-22, operators
• Chloroform may also be used as a fumigant for stored grain in municipal & industrial waste water treatment plants &
crops (2), although it is not registered for this use in Canada (12). incinerators, and lifeguards or others who work in or near
• In 1995 there were 19 countries producing chloroform world pools and spas (where chloroform is produced as a result
wide (13). of the reaction between chlorine and organic material) (2).
• The US, EU and Japan are the main manufacturers of • Other potential exposures include workers in the building and
chloroform with a total global capacity of approximately paperboard industry, dry cleaning, breweries, and pulp & paper
520,000 tonnes per year in the late 1990s (14). mills (2).
• Many provinces collect samples of workplace exposures as part
use in Canada
of their regulatory practices. The numbers of chloroform samples
• The main use of chloroform in Canada is in the production
included in the databases of two provinces are presented in the
of HCFC-22 (a replacement for the ozone-depleting chloro-
fluorocarbons, or CFCs). This use is declining, however, since
HCFCs also deplete ozone in the atmosphere (albeit at a much Canadian Occupational Samples
slower rate than conventional CFCs) (15).
PRoVINCE # of SAmPLES dAtE
• HCFCs are also currently used in the production of polytetra
fluoroethylene (PTFE, or Teflon®), keeping demand steady Ontario 113 1981-2004
for chloroform in the short term, but HCFC-22 is slated to be
BC 193 1981-2004
phased out between 2010 and 2020 (11).
• Use of chloroform in cosmetics and pharmaceuticals is prohibited in • The pilot CAREX Canada project did not generate exposure
Canada under the Food and Drug Act (11). Labelling of chloroform estimates for chloroform.
containing products is regulated under the Hazardous Products
Act (11). Environmental Exposures
• The primary route of exposure is ingestion of chloroform via
Searches of MSDS and industry databases yielded the following
chlorinated drinking water (2). Chloroform is produced during
results on current usage of chloroform in Canada:
drinking water treatment by the reaction between chlorine and
decomposing organic material (13). Typical concentrations of
dAtABASE SEARCh tERm RESuLt
chloroform in Canadian chlorinated water range from 10 to
ChemSources 90 µg/litre (or parts per billion, ppb) (11, 13).
‘chloroform’ 1 supplier
(16) • Chlorinated water can also release aerated chloroform
(i.e. during showering), creating an inhalation risk (2). Dermal
absorption of chloroform from water can also occur (2).
Industry 3 chemical • CAREX Canada is reviewing Canadian exposure to chlorination
Canada’s ‘chloroform’ manufacturers, by-products as a group; please see the relevant Carcinogen
CCC (17) 2 environmental
Profile for more information.
• Chloroform is also found in ambient air and at low levels in some
foods (such as milk and butter) (3).
Canadian Production & trade
• Most chloroform in the environment is released by industrial
Production and Trade sources, including pulp and paper mills, municipal wastewater
ACtIVItY QuANtItY YEAR (REf) treatment plants, chemical manufacturing plants and waste
Canadian Not manufactured in 2001 • Once present, chloroform may persist in ground water for many
Production Canada since 1978 (11)
years (5), but it does not bioaccumulate in aquatic animals (13).
Domestic 1995 • Although chloroform is not produced in Canada, it enters
300 tonnes (15)
Consumption the environment through industrial releases and long range
atmospheric transport from other non-Canadian cities (11).
• Chloroform has been detected in Canadian air, surface water
5 tonnes of and groundwater samples (19).
‘chloroform • From 1989 to 1996, chloroform was detected in approximately 69%
to US (18)
(trichloromethane)’ of 8,807 24-h samples of indoor air collected across Canada (20).
Import • Concentrations were higher at urban sites and immediately
adjacent to major roadways (20).
50 tonnes of
from US (18)
CARCINOGEN PROFILE: Chloroform
• Comparison between two time periods (19891992 and 10. CEPA Priority Substance Assessment Program: Second Priority
1993-1996) found that chloroform concentrations were Substance List under CEPA (1999)
slightly lower in the more recent period (20).
• In 2001, it was estimated that the average Canadian daily 11. Priority Substances List Assessment Report: Chloroform (2001)
exposure to chloroform was between 0.6 and 10.3 µg/kg-bw http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/
per day; the highest exposure was calculated for infants who
were formula fed (11). 12. Pesticides Management Regulatory Agency (PMRA), Health Canada:
• Searches of environmental and consumer product databases Registered products database
yielded the following results on current potential for exposure http://pr-rp.pmra-arla.gc.ca/portal/page?_
to chloroform in Canada:
13. CICAD 58: Chloroform. Geneva, WHO (2004)
NPRI and Household Products Database http://www.who.int/ipcs/publications/cicad/en/cicad58.pdf
NPRI 2006 (21) 14. McCulloch A (2003) ‘Chloroform in the environment: occurrence,
sources, sinks and effects.’ Chemosphere, 50:1291–1308.
Search Term: ‘chloroform’
Results: 13 companies 15. CPI Product Profiles, Camford Information Services: Chloroform (1996)
CAtEGoRY QuANtItY INduStRY 16. ChemSources database for international chemical suppliers (free
Released into subscription required)
64 tonnes http://db.chemsources.com/cgi-bin/foxweb.exe/validate_user@csi/login
Environment Pulp & paper
mills and 17. Industry Canada’s CCC database
Disposed of 4 tonnes
Sent to off-site manufacturers do?lang=eng&prtl=1&app=1
18. TradeMap (Canadian international trade data, free subscription required)
houSEhoLd PRoduCtS 2008 (22) http://www.trademap.org/canada/Index.aspx
Results: 1 product 19. CEPA Environmental Registry, Notices: chloroform; 2000-06-03 -
Canada Gazette Part I, Vol. 134 No. 23
SEARCh tERm QuANtItY PRoduCt tYPE http://www.ec.gc.ca/CEPARegistry/Notices/NoticeText.cfm?intNotice=
‘chloroform’ 1 Glue remover
20. Concord Environmental Corporation (1992) Results of a national pilot
survey of airborne volatile organic compounds in Canadian residences.
Vols. 1 and 2. Downsview, Ontario, Concord Environmental Corporation
(CE J2431) (cited in Reference 11)
SouRCES 21. The National Pollutant Release Inventory
1. Wikimedia Commons Photo: Chloroform:
http://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/ 22. Household Products Database (US)
2. NTP 11th report on carcinogens for Chloroform (2005)
3. IARC monograph: Some Chemicals that Cause Tumours of the Kidney
or Urinary Bladder in Rodents, and Some Other Substances 1999; 674 1. Government of Canada (2006), Guidelines for Canadian Drinking Water
pages; ISBN 92 832 1273 8 , Volume 73 (1999) Chloroform: Quality: Guideline Technical Document: Trihalomethanes
4. Hazardous Substances Data bank (search term: chloroform)
http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB 2. Government of Ontario, Drinking Water Information Sheet (2007)
5. ATSDR Toxicological Profile for Chloroform (1997)
http://www.atsdr.cdc.gov/toxprofiles/tp6.pdf 3. US Department of Labour, Occupational Safety & Health Guideline
6. ATSDR ToxFAQ Sheet: Chloroform (1997) http://www.osha.gov/SLTC/healthguidelines/chloroform/recognition.html
4. Toxicological Review of Chloroform, Environmental Protection Agency,
7. Guidelines for Canadian Drinking Water (2008) US (2001)
5. Chloroform, Integrated Risk Information System (IRIS), EPA Website
8. Exposure Guidelines for Residential Indoor Air Quality (1987) http://www.epa.gov/iris/subst/0025.htm
9. Health Canada’s Prioritization of the DSL (2006)
CARCINOGEN PROFILE: Chloroform
Published January 2009
updated december 2009
We are CAREX Canada, a research unit based in the School of
Environmental Health in the University of British Columbia and funded by
Health Canada through the Canadian Partnership Against Cancer. We are
developing estimates of the number of Canadians exposed to carcinogens
in workplace and community environments. These estimates have been
compiled to the best of our ability using the data, the facilities and other
resources available to us and are for general information only. While every
effort has been made to ensure that this information is accurate and current,
we assume no responsibility for errors, omissions or outdated information
provided on this fact sheet. This information is not intended to serve as
medical advice, diagnosis, treatment nor care, and should not replace proper
consultation with healthcare professionals. Consult a qualified healthcare
professional before making medical decisions or if you have questions about
your individual medical situation. The views expressed herein represent the
views of CAREX Canada.
School of Environmental Health
University of British Columbia
3rd Floor — Library Processing Center
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Vancouver, BC, V6T 1Z3
CARCINOGEN PROFILE: Chloroform