Coal tars and their distillates - information sheet 

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  • The Government of Canada conducts risk assessments of substances under the Canadian Environmental Protection Act, 1999 (CEPA 1999) to determine whether they present or may present a risk to human health or to the environment.
    • The risks posed by a substance are determined by both its hazardous properties (potential to cause adverse human health or ecological effects) and the amount or extent of exposure to people and the environment.
    • When needed, the Government implements risk management measures under CEPA 1999 and other federal acts to help prevent or reduce potential harm.
  • The Government concluded that coal tars and their distillates are harmful to human health and to the environment at levels of exposure considered in the assessment. The conclusions of the assessment cover all coal tars and their distillates, including the 6 substances covered in the screening assessment.
  • Risk management was proposed to address the exposures of concern, as detailed below.

About these substances

  • The screening assessment focused on 6 substances, referred to collectively as coal tars and their distillates under the Chemicals Management Plan (CMP). The summary of Stream 0 substances and publications includes details on the substance names and CAS Registry Numbers (RNs).
  • These substances are coal tar, low-temperature coal tar, high-temperature coal tar, coal tar oils, coal tar upper distillates, and high-temperature coal tar pitch.
  • Data obtained on these 6 substances were used to assess the risk from all coal tars and their distillates, including residues. As such, the conclusions of this assessment are considered to cover coal tars and their distillates including, but not limited to, the 6 substances identified
  • Coal tars are substances obtained from the heating of coal in the absence of oxygen, a process that occurs at integrated steel mills. Coal tar distillates result from the distillation of coal tars at coal tar refinery facilities.
  • All coal tar compounds are considered to be substances of Unknown or Variable composition, Complex reaction products, or Biological materials (UVCBs). They are made of complex combinations of compounds, mainly aromatic hydrocarbons. The composition of coal tars and their distillates varies based on their source, the heating temperature, and the distillation temperature for the distillates.
  • For the screening assessment, benzene and polycyclic aromatic hydrocarbons (PAHs) were identified as the hazardous components in coal tar substances.
  • Benzene, a component of coal tars and their distillates, was assessed by Health Canada and Environment Canada previously and was added to Schedule 1 to CEPA 1999.
  • PAHs were also assessed by Health Canada and Environment Canada as they were identified on the first Priority Substance List. They were added to Schedule 1 to CEPA 1999.
  • According to information gathered by the Government, coal tars are used in the production of other substances, such as coal tar distillates. Coal tar is also used as an active ingredient in human and veterinary drugs, primarily in the form of shampoos used to treat skin conditions, such as psoriasis, eczema and seborrheic dermatitis.
  • Coal tar oils and upper distillates are used as raw material in the production of carbon black and in chemical manufacturing.
  • Coal tar pitch is primarily used as a binder in the aluminum industry, but may also be used as an adhesive/binder in clay pigeons (for target shooting) and briquettes for lining industrial furnaces, in pavement sealants and roofing systems.

Human and ecological exposure

  • Canadians may be exposed to coal tars and their distillates dermally (through skin contact) from the use of products available to consumers (for example, pavement sealants), and orally from house dust containing low levels of components of coal tar-based pavement sealants.
  • It is also recognized that there may be inhalation exposure for people living in the vicinity of coal tar production (for example, integrated steel mills) and refining facilities.
  • Soil and water organisms may be exposed to coal tars and their distillates following the release of these substances into air from industrial facilities.
  • Exposure to water and sediment organisms may also occur, from runoff released from paved surfaces coated with coal tar-based sealant.

Key health and ecological effects (hazard)

  • To help inform the health hazard information, international reports of data were reviewed. Coal tars and their distillates have been classified by international agencies as a carcinogen (potentially causes cancer). Therefore, the critical effect on human health considered in this assessment is carcinogenicity.
  • Benzene is a hazardous component of coal tars and their distillates, representing the highest health concern for exposure over longer periods of time. It has been identified as a carcinogen by Health Canada and several international agencies. For example, it is classified by the International Agency for Research on Cancer (IARC) as "possibly carcinogenic to humans". PAHs have also been identified by Health Canada and international agencies as "probably carcinogenic to humans".
  • Most PAHs in coal tars and their distillates have demonstrated short and long-term toxicity to aquatic and terrestrial organisms. Additional toxicity from other non-PAH components in coal tars may add to the overall ecotoxicity of coal tar substances.

Risk assessment outcomes

  • It was determined that these substances may pose a risk to human health. This was based upon a comparison of levels to which people in Canada may be exposed to coal tars and their distillates from living near coal tar producers and refineries and also from coal tar-based sealants, and levels associated with the critical health effect.
  • Considering all information presented, it was also determined that there is a risk to the environment from coal tars and their distillates.

Screening assessment conclusions

  • The Government concluded that coal tars and their distillates are harmful to human health at levels of exposure considered in the assessment.
  • The Government also concluded that these substances are entering or may enter the environment at levels that are harmful.

Preventive actions and risk reduction

  • The proposed order adding coal tars to Schedule 1 to CEPA 1999, also called the List of Toxic Substances, was published for a 60-day public comment period ending on August 25, 2021. Adding a substance to the list does not restrict its use, manufacture or import. Rather, it enables the Government to take risk management actions under CEPA 1999.
  • In December 2018, a mandatory notice issued under section 71 of CEPA 1999 was published to gather information on these substances to inform risk management activities. A summary of the information received in response to the data gathering is available through the Government of Canada Open Data Portal.
  • Publication of the risk management approach aims to inform stakeholders of proposed risk management options and continue discussion about their development. To address human health and ecological concerns, the Government is considering the following actions:
    • Development of regulations that would prohibit the manufacture, import and sale of coal tar-based sealant products in Canada;
    • Development of a pollution prevention planning notice to prevent and control emissions of coal tars and their distillates from coal tar refining facilities; and
    • Working with the Government of Ontario, notably the Ministry of the Environment, Conservation and Parks, and industry to evaluate effectiveness of provincial and federal risk management measures to reduce emissions of benzene and benzo(a)pyrene (a PAH), major components of coal tars, at integrated steel mills.
  • Risk management actions may evolve through consideration of assessments and risk management options or actions published for other CMP substances. This is to ensure effective, coordinated, and consistent risk management decision-making.

Where to find updates on risk management activities

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