Quinoline

CAS Registry Number 91-22-5

What is it?

• Quinoline is a substance that occurs naturally in coal and coal-related compounds such as coal tar and creosote.

How is it used?

• Coal tar is recovered and distilled in Canada to produce oils (naphthalene, creosote, and carbon black feedstock) and coal tar pitch. Quinoline is a natural component of coal tar-based products which are used in wood preservation, aluminum smelters, graphite electrodes, specialty carbon products, pavement coatings/sealants and refractory products.
• Internationally, although unconfirmed in Canada, quinoline is used as a solvent in the production of dyes, paints and other chemicals. It is also used as a reagent, a corrosion inhibitor, and in the manufacture of pharmaceuticals and veterinary drugs.
• Quinoline is manufactured in or imported into Canada as part of mixtures where it represents less than 1% of the composition.

Why did the Government of Canada assess it?

• Prior to assessment, quinoline was identified as a potential concern to the environment and human health based on information regarding possible accumulation in organisms and potential to cause harm to organisms, and based on a high potential for exposure (not including workplace exposures) to the general population of Canada.

How is it released to the environment?

• Quinoline may be formed as a trace pollutant during incomplete combustion of nitrogen-containing substances (for example, petroleum, coal).
• Quinoline may be released to groundwater and surface water from industrial sites where coal tar and creosote have leaked into the ground from storage tanks or from the disposal of such products.
• These releases can occur at industrial sites such as coal tar distillate (creosote) facilities, wood-impregnation plants, abandoned coal gasification plants, steel plants equipped with coke ovens, aluminum smelters and waste incinerators. However, it should be noted that measures of environmental protection have been implemented in Canada, in particular for steel plants equipped with coke ovens and for wood preservation facilities.

How are Canadians exposed to it?

• Exposure of the general population of Canada to quinoline is expected to be low and to occur predominantly through the inhalation of air.
• Canadians are exposed to quinoline from its presence in tobacco smoke and from incomplete combustion of nitrogen-containing substances (for example, petroleum, coal).

What are the results of the assessment?

• The Government of Canada has conducted a science-based evaluation of quinoline, called a screening assessment.
• Screening assessments address potential for harm to the general population in Canada (not including workplace exposures) and the environment.

• Results of this final screening assessment indicate that although quinoline is not expected to accumulate in organisms, the substance may remain in the environment for a long time.
• Furthermore, the quantity of quinoline that may be released to the environment is above the level expected to cause harm to organisms.
• The Government of Canada has therefore concluded that quinoline is entering or may enter the environment in a quantity or under conditions that constitute a danger to the environment.
• The Government of Canada has also concluded that quinoline may be considered to be harmful to human health.

What is the Government of Canada doing?

• Exposure of the general population of Canada is currently considered to be low and the Government of Canada is taking action so that exposure remains low.
• The application of the Significant New Activity (SNAc) provisions to this substance is being recommended. This would require that any proposed new manufacture, use or import be subject to further assessment, and would determine if the new activity requires further risk management consideration.
• In Canada, many industrial sites (including former coal gasification plants) have been assessed and work has been done to remediate these sites under provincial authorities. Existing Canadian Council of Ministers of the Environment (CCME) guidelines for quinoline in surface water and soil will be reviewed and updated, if necessary, in order to guide the assessment and clean up of contaminated sites.
• Creosote, a registered material preservative in wood and lumber preservation under the Pest Control Products Act, may contain trace levels of quinoline. Health Canada's Pest Management Regulatory Agency (PMRA) recently conducted a re-evaluation of creosote and determined current pesticidal uses together with restrictions so that releases of creosote to the environment are minimized and are still acceptable.
• A State of the Science Report for Quinoline was completed by Health Canada Web in May 2005.
• The final screening assessment report and risk management approach documents were published on November 19, 2011. The risk management approach document will be followed by a 60-day public comment period, ending January 18, 2012.

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).

• As a general precaution, Canadians are reminded to carefully follow safety warnings and directions, including those on labels, when using products containing quinoline.

• Tobacco smoke is also a source of quinoline. Canadians are reminded that they should not smoke and avoid second-hand smoke. For more information about smoking, how to quit and how to protect your family from second-hand smoke, please visit the Health Concerns - Tobacco section of Health Canada's Web site or speak with a doctor.
• Canadians who handle quinoline or products containing it in the workplace should consult with their occupational health and safety representative about safe handling practices, and requirements under the Workplace Hazardous Materials Information System (WHMIS).