Chloroform CARCINOGEN

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					 CARCINOGEN PROFILE


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

                                                                           ON                                                    10

                                                                           QC                                                    5 [sk]

                                                                                                                                 10
                                                                           NT, NU
                                                                                                                                 50 [stel]
Wikimedia Commons Photo: Chloroform (1)                                    othER JuRISdICtIoNS                                   oEL (ppm)
IARC monograph Vol. 73, 1999
(Group 2B)                                                                 ACGIH 2008 TLV                                        10

                                                                           SCOEL                                                 2 [sk]

                                                                                                                                 2
                                                                           Sweden LLV
                                                                                                                                 5 [stel]
                                                                                                                                 0.5
                                                                           German MAK
                                                                                                                                 1 [stel]
                                                                         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
                                                                                                                                               YEAR
of chlorination of drinking water, known as trihalomethanes. There         JuRISdICtIoN                           LImIt
                                                                                                                                               (REf)
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
                                                                                                                  None
                                                                           Air Quality                                                         (8)
Several epidemiological studies have suggested that exposure to
chloroform in chlorinated drinking water is associated with excess
                                                                         Canadian Agencies/Organizations
cancers, particularly of the urinary bladder, colon and rectum (3).
Causality, however, can not be determined because of uncertainties,                                                                            YEAR
                                                                           AGENCY                      dESIGNAtIoN/PoSItIoN
                                                                                                                                               (REf)
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).
                                                                            Main Uses
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-
                                                                              following table:
   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
                                               5 companies
                                                                                 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.
                                               companies
                                                                           •	 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
                                                                              incinerators (11).
  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).
  Export
                                                                           •	 Chloroform	has	been	detected	in	Canadian	air,	surface	water	
                       5 tonnes of                                            and groundwater samples (19).
  Mainly                                              2007
                       ‘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
  Mainly                                              2007
                       ‘chloroform
  from US                                             (18)
                       (trichloromethane)’




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)
                                                                                http://www.ec.gc.ca/substances/ese/eng/psap/psap_3.cfm
      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/
                                                                                contaminants/psl2-lsp2/chloroform/chloroform_e.pdf
   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?_
                                                                                pageid=34,6928,34_6960:34_7232&_dad=portal&_schema=PORTAL
   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
                                                         chemical               http://strategis.ic.gc.ca/app/ccc/srch/cccBscSrch.
     Sent to off-site                                    manufacturers          do?lang=eng&prtl=1&app=1
                                 0 tonnes
     recycling
                                                                          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=
                                                                                46&intDocument=302
     ‘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
                                                                                http://www.ec.gc.ca/pdb/querysite/query_e.cfm
1.   Wikimedia Commons Photo: Chloroform:
     http://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/            22. Household Products Database (US)
     Chloroform-3D-vdW.png/717px-Chloroform-3D-vdW.png                        http://hpd.nlm.nih.gov/

2.   NTP 11th report on carcinogens for Chloroform (2005)
     http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s038chlo.pdf
                                                                                othER RESouRCES
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
     http://monographs.iarc.fr/ENG/Monographs/vol73/mono73-10.pdf               http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/
                                                                                water-eau/trihalomethanes/trihalomethanes-eng.pdf
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)
                                                                                http://www.ontario.ca/drinkingwater/158462.pdf
5.   ATSDR Toxicological Profile for Chloroform (1997)
     http://www.atsdr.cdc.gov/toxprofiles/tp6.pdf                         3.    US Department of Labour, Occupational Safety & Health Guideline
                                                                                for Chloroform
6.   ATSDR ToxFAQ Sheet: Chloroform (1997)                                      http://www.osha.gov/SLTC/healthguidelines/chloroform/recognition.html
     http://www.atsdr.cdc.gov/tfacts6.pdf
                                                                          4.    Toxicological Review of Chloroform, Environmental Protection Agency,
7.   Guidelines for Canadian Drinking Water (2008)                              US (2001)
     http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/            http://www.epa.gov/NCEA/iris/toxreviews/0025-tr.pdf
     water-eau/sum_guide-res_recom/summary-sommaire-eng.pdf
                                                                          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
     http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/
     air/exposure-exposition/exposure-exposition-eng.pdf

9.   Health Canada’s Prioritization of the DSL (2006)
     http://www.hc-sc.gc.ca/ewh-semt/contaminants/existsub/categor/_
     result_substance/index-eng.php




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.




CAREX Canada
School of Environmental Health
University of British Columbia
3rd Floor — Library Processing Center
2206 East Mall
Vancouver, BC, V6T 1Z3
Canada

T. 604-822-0837
F. 604-822-9588
E. info@carexcanada.ca

www.carexcanada.ca




CARCINOGEN PROFILE: Chloroform