Backgrounder on Batch 4 of the Chemicals Management Plan

Out of the 18 substances assessed in Batch 4, four may pose a risk to human health and one may be harmful to the environment.

Two of the substances that may pose a risk to human health (dimethyl sulfate, diethyl sulfate) and the one substance that is proposed as harmful to the environment, benzenamine (BNST), will be added to the list of toxic substances under the Canadian Environmental Protection Act, 1999.

The other two substances of concern to human health – butane and isobutane containing more than 0.1% 1,3-butadiene – were assessed based upon the presence of 1,3-butadiene, a substance already included on Schedule I of CEPA,1999. The assessment concluded that butane and isobutane containing more than 0.1% 1,3-butadiene, were not significant contributors to Canadians’ overall exposure to 1,3 butadiene.  In light of this new information, Health Canada is proposing that the existing risk management strategy for 1,3-butadiene be reviewed and updated.

The draft environmental assessment for Benzenamine (BNST) shows that it is a substance that can harm the environment because it stays in the environment for a long time and builds up in aquatic organisms and wildlife.  The Government is proposing to add the substance to the Virtual Elimination List, in order to reduce environmental releases of this substance to a level where it can no longer be measured.

New information on the remaining 13 substances, received as part of the call for information for Batch 4, demonstrates that they do not pose a risk to the environment or human health because exposure to these substances is not significant enough to cause effects, and some substances are no longer in commerce in Canada. 

However, five of these substances could harm the environment if they were used in larger quantities within Canada. To protect the environment the Government is proposing that Significant New Activity provisions be applied to these five substances which will prevent anyone from using them in the future without undergoing a new series of assessments.

Risk Management Scope documents outlining proposed risk management actions for the substances of concern to human health and the environment will be released at the same time as the draft screening assessment reports. The information provided by stakeholders during the public comment period will help to determine the best approach to manage these substances.

Following the public comment period on the draft assessments and risk management scopes, final conclusions will be published no later than August 1, 2009, in the Canada Gazette, Part I.

Under the Chemicals Management Plan, legacy chemicals that have not previously undergone rigorous scientific assessment in Canada are being addressed. The Government is challenging industry and other stakeholders (academics and non-governmental organizations) to provide information on approximately 200 priority chemical substances and how they are currently used in Canada. This is known as the Challenge. 

Beginning in February 2007, and about every three months, profiles of 12 to 20 of these chemical substances are released.  Four months (or up to six, with written request) are given for stakeholders to respond, after which time, government scientists review all the information provided. The draft screening assessment reports and risk management scopes are the first stage in reviewing the information provided. From this information, possible adverse effects on the environment and human health are determined, and substances that may require risk management strategies are identified.

Butane

CAS Registry Number 106-97-8

What is it?

• Butane is an industrial chemical and is produced from refining crude oil and through the processing of natural gas.
• Butane also contains very small amounts of 1,3-butadiene, which is produced during the refining of butane.  1,3-Butadiene has previously been assessed by the Government of Canada (link) and is considered to be harmful to human health.

How is it used?

• Butane is used as a solvent/carrier, blowing agent/propellant in some aerosol spray products, fuel or fuel additives, and as a formulation component.  
• Butane is also used in various applications including insulating polyurethane foam, aerosol sprays and coatings, paint dyes and automotive spray waxes.
• Butane is also used in motor vehicle gasoline and liquefied petroleum gas.
• Butane is also reported to be used as a propellant in some aerosol-based natural health products and therapeutic products. Butane is also used in certain pest control products as propellants, however, these pest control products do not contain 1,3-butadiene.
• Based on the most recent data available, butane containing very low amounts of 1,3-butadiene is manufactured in Canada and imported into Canada.

Why did the Government of Canada assess it?

• Butane was identified as a potential concern for human health based on its classification by an international organization as a substance which was found to cause cancer when it contains 1,3-butadiene. 
• Butane was believed to be a high potential for exposure to Canadians.
• Butane was assessed by Government of Canada scientists to help decide if further actions might be necessary so that the health of Canadians and the environment are protected.
• The focus of this assessment was to evaluate the exposure to and potential risk to human health from 1,3-butadiene in butane in Canada.

How are Canadians exposed to it?

• Exposure to butane from the use of products containing 1,3-butadiene is expected to be low.

What is the Government of Canada doing?

• The Government of Canada has conducted an evaluation of butane based on science.

• Risk management activities for 1,3-butadiene are in place (link).  The Government of Canada will examine the existing risk management activities so that they are appropriate and take into account any new information regarding exposure to 1,3-butadiene in butane.
• Butane that does not contain 1,3-butadiene will also be assessed at a later stage in the Chemicals Management Plan to see if additional action is needed.

• The assessment was published on January 24, 2009 and will be followed by a 60-day comment period, ending March 25, 2009.

What should Canadians do?

• Because Canadians’ exposure to 1,3-butadiene in butane is low,  Canadians do not need to take any specific actions to reduce their exposure.
• Canadians are reminded to follow safety warnings and directions for use carefully when using products.

Propane, 2-methyl (Isobutane)

CAS Registry Number 75-28-5

What is it?

• 2-Methylpropane, also known as isobutane, is an industrial chemical and also occurs naturally in oil and gas fields.
• Isobutane also contains very low amounts of 1,3-butadiene, which is produced during the refining of isobutane.  1,3-Butadiene has previously been assessed by the Government of Canada (link) and is considered to be harmful to human health.

How is it used?

• Isobutane is used as a solvent/carrier, blowing agent/propellant, fuel or fuel additive and formulation component.  It is also used in some aerosol-based consumer products.  Isobutane is also used in some consumer products such as cosmetic/beauty preparations, air fresheners, cleaners, activator/primers and various coatings. It is considered safe as a cosmetic ingredient when used appropriately.
• Isobutane is also used in motor vehicle gasoline and liquefied petroleum gas.
• Isobutane is also reported to be used as a propellant in some aerosol-based natural health products and therapeutic products.  Isobutane is also used in certain pest control products as propellants, however, these pest control products do not contain 1,3-butadiene.
• Based on the most recent data available, isobutane containing very low amounts of 1,3-butadiene is manufactured in Canada and imported into Canada.

Why did the Government of Canada assess It?

• Isobutane was identified as a potential concern for human health based on its classification by an international organization as a substance which was found to cause cancer when it contains 1,3-butadiene. 
• Isobutane was believed to be a high potential for exposure to Canadians.
• Isobutane was assessed by Government of Canada scientists to help decide if further actions might be necessary so that the health of Canadians and the environment are protected.
• The focus of this assessment was to evaluate the exposure to and potential risk to human health from, 1,3-butadiene in isobutane in Canada.

How are Canadians exposed to it?

• Exposure to isobutane from the use of products containing 1,3-butadiene is expected to be low.

What is the Government of Canada doing?

• The Government of Canada has conducted an evaluation of isobutane based on science.
• Risk management activities for 1,3-butadiene are in place (link).  The Government of Canada will examine the existing risk management activities so that they are appropriate and take into account any new information regarding exposure to 1,3-butadiene in butane. 
• Isobutane that does not contain 1,3-butadiene will also be assessed at a later stage in the Chemicals Management Plan to see if additional action is needed.
• The assessment was published on January 24, 2009 and will be followed by a 60-day comment period, ending March 25, 2009.

What should Canadians do?

• Because Canadians’ exposure to 1,3-butadiene in butane is low,  Canadians do not need to take any specific actions to reduce their exposure.
• Canadians are reminded to follow safety warnings and directions for use carefully when using products.

Sulfuric acid, dimethyl ester (Dimethyl sulfate)

CAS Registry Number 77-78-1

What is it?

• Sulfuric acid, dimethyl ester, also known as dimethyl sulphate, is an industrial chemical.

How is it used?

• Dimethyl sulfate is used in Canada in the manufacture of pharmaceuticals.
• Based on the most recent data available, dimethyl sulphate is not manufactured in Canada, but is imported into Canada.

Why did the Government of Canada assess It?

• Dimethyl sulfate was identified as a potential concern for human health based principally on its classification by an international organization as a substance which was found to cause cancer and genetic damage damage in some studies with laboratory animals. 
• Dimethyl sulphate was also believed to have a moderate potential for exposure to Canadians.
• Dimethyl sulphate was assessed by Government of Canada scientists to help decide if further actions might be necessary so that the health of Canadians and the environment are protected.

How are Canadians exposed to it?

• Exposure to dimethyl sulfate is expected to be very low.

What Is the Government of Canada doing?

• The Government of Canada has conducted an evaluation of dimethyl sulfate, called a screening assessment.
• The Government of Canada has proposed that dimethyl sulphate is considered to be harmful to human health.
• Although Canadians exposure is very low, the Government is taking action so that exposure remains low.
• Risk management options include the development of a future notification tool so that new uses in Canada do not increase exposure for Canadians and to investigate the formulation of dimethyl sulfate in emissions from industrial operations to see if controls are needed.
• The screening assessment and the proposed risk management scope were published on January 24, 2009 and will be followed by a 60-day comment period, ending March 25, 2009.

What should Canadians do?

• Because exposure to dimethyl sulfate is very low, Canadians do not need to take any specific actions to reduce their exposure

Sulfuric acid, diethyl ester (Diethyl sulfate)

CAS Registry Number 64-67-5

What is it?

• Sulfuric acid, diethyl ester, also known as diethyl sulphate, is an industrial chemical.

How is it used?

• Diethyl sulfate is used in Canada in the manufacturing of tissue paper as a softener to increase absorbency.
• Based on the most recent data available, diethyl sulphate is not manufactured in Canada, but is imported into Canada.

Why did the Government of Canada assess It?

• Diethyl sulfate was identified as a potential concern for human health based principally on its classification by an international organization as a substance which was found to cause cancer and genetic damage in some studies with laboratory animals.  
• Diethyl sulphate was also believed to have a moderate potential for exposure to Canadians.
• Diethyl sulphate was assessed by Government of Canada scientists to help decide if further actions might be necessary so that the health of Canadians and the environment are protected.

How are Canadians exposed to it?

• Exposure to diethyl sulphate is expected to be very low.

What is the Government of Canada doing?

• The Government of Canada has conducted an evaluation of diethyl sulfate called a screening assessment.
• The Government of Canada has proposed that diethyl sulfate is considered to be harmful to human health.
• Although Canadians exposure is very low, the Government is taking action so that exposure remains low.
• Risk management options include the development of a future notification tool so that new uses in Canada do not increase exposure for Canadians.
• The screening assessment and the proposed risk management scope were published on January 24, 2009 and will be followed by a 60-day comment period, ending March 25, 2009.

What should Canadians do?

• Because exposure to diethyl sulfate is very low, Canadians do not need to take any specific actions to reduce their exposure.