Archived Site-restricted gas oils

CAS Registry Number 68333-25-5

What is it?

• Gas oils are a category of complex petroleum mixtures. Their composition varies with the source of crude oil or bitumen, and the processing steps involved.
• Gas oils are composed of varying lengths of carbon atom chains, generally ranging between 9 and 25 carbon atoms.
• Gas oils are considered to be of Unknown or Variable composition, Complex reaction products or Biological materials (UVCBs).
• Site-restricted gas oils are not expected to be transported off petroleum refinery and upgrader facility sites.

How is it used?

• Gas oils are used in the production of fuels that are used in diesel engines and for both industrial and domestic heating. Some of these products may also be used as solvents.
• The gas oil assessed in this screening assessment is only found within petroleum refinery and upgrader facility sites.

Why did the Government of Canada assess it?

• This gas oil was included in the Petroleum Sector Stream Approach (Stream 1) under the Chemicals Management Plan for the screening assessment of potential risks to the environment and to human health.
• Prior to its assessment by the Government of Canada, this site-restricted gas oil was identified as a potential concern for human health based on its classification by international organizations as a substance that may cause cancer, and based on a moderate or high potential for exposure (not including workplace exposures) to the general population of Canada.
• It was not identified as a potential concern to the environment based on available information regarding possible persistence, accumulation and potential to cause harm to non-human organisms.

How are Canadians exposed to it?

• The general population is not expected to be exposed to this site-restricted gas oil since it is not expected to be transported off petroleum refinery or upgrader facility sites.

How is it released into the environment?

• The gas oil considered in this report has been identified as site-restricted (in other words, it is not expected to be transported off refinery or upgrader facility sites); it is either consumed on site or blended into substances leaving the site under different CAS Registry Numbers (which will also be addressed under the Chemicals Management Plan).
• Releases of this site-restricted gas oil are captured into a closed system and then returned to the processing facility for re-use or they are sent to the facility wastewater treatment plant where they are removed from the wastewater.

What are the results of the assessment?

• The Government of Canada has conducted a science-based evaluation of site-restricted gas oil, called a screening assessment.
• Screening assessments address the potential for harm to the general population of Canada (not including workplace exposures) and the environment.
• Results of the final screening assessment indicate that this site-restricted gas oil is not expected to be transported off petroleum refinery or upgrader facility sites.
• The Government of Canada has therefore concluded that this site-restricted gas oil is not entering the environment in a quantity or under conditions that constitute a danger to the environment.
• The Government of Canada has also concluded that this site-restricted gas oil is not harmful to the health of the general population as exposure is not expected.
• Gas oils that are not site-restricted and substances into which this site-restricted gas oil may be blended will be addressed at a later stage under the Chemicals Management Plan.

What is the Government of Canada doing?

• Exposure of the general population of Canada to this site-restricted gas oil is currently not expected and the Government of Canada is proposing action to limit the potential for future exposure.
• The final screening assessment report was published on September 10, 2011.

What can Canadians do?

• The health risks associated with a chemical depend on the hazard (its potential to cause health effects) and the dose (the amount of chemical to which you are exposed). This site-restricted gas oil is not presently a concern for the environment or human health as exposure is not expected.
• Canadians who may be exposed to gas oils in the workplace should consult with their occupational health and safety representative about safe handling practices, applicable laws and requirements under the Workplace Hazardous Materials Information System (WHMIS).