Archived Site-restricted low boiling point Naphthas

(Site-restricted LBPNs)

CAS Registry Numbers

• 64741-54-4
• 64741-55-5
• 64741-64-6
• 64741-74-8
• 64742-22-9
• 64742-23-0
• 64742-73-0
• 68410-05-9
• 68410-71-9
• 68410-96-8
• 68476-46-0
• 68477-89-4
• 68478-12-6
• 68513-02-0
• 68514-79-4
• 68606-11-1
• 68783-12-0
• 68919-37-9
• 68955-35-1
• 101795-01-1

What are they?

• Low boiling point naphthas (LBPNs) are a category of complex petroleum mixtures. Their composition varies with the source of crude oil or bitumen and the processing steps involved.
• They are composed of varying lengths of carbon atom chains, generally ranging between 4 and 12 carbon atoms.
• LBPNs are considered to be of Unknown or Variable composition, Complex reaction products or Biological materials (UVCBs).
• Site-restricted LBPNs are not expected to be transported off petroleum refinery or upgrader facility sites.

How are they used?

• Site-restricted LBPNs are used as blending constituents in the production of gasoline or are further refined into other products.

Why did the Government of Canada assess them?

• Twenty site-restricted LBPNs were 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 their assessment by the Government of Canada, these twenty site-restricted LBPNs were identified as a potential concern for human health based on their classification by international organizations as substances that may cause cancer, and based on a moderate or high potential for exposure (not including workplace exposures) to the general population of Canada.
• Some were also 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 them?

• The general population is not expected to be exposed to site-restricted LBPNs since they are a subset of substances that are not expected to be transported off petroleum refinery and upgrader facility sites.

How are they released into the environment?

• The LBPNs considered in this report have been identified as site-restricted (in other words, they are not expected to be transported off refinery or upgrader facility sites); they are 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 site-restricted LBPNs 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 LBPNs, 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 these site-restricted LBPNs are not expected to be transported off petroleum refinery or upgrader facility sites.
• The Government of Canada has therefore concluded that these twenty site-restricted LBPNs are 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 these site-restricted LBPNs are not harmful to the health of the general population as exposure is not expected.
• LBPNs that are not site-restricted and substances into which site-restricted LBPNs 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 these site-restricted LBPNs 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). These site-restricted LBPNs are not presently a concern for the environment or human health as exposure is not expected.
• Canadians who may be exposed to LBPNs 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).