Summary of public comments received on the draft screening assessment and risk management scope for benzotriazoles and benzothiazoles group

Comments on the draft Screening Assessment and Risk Management Scope for Benzotriazoles and Benzothiazoles, assessed under the Chemicals Management Plan (CMP), were submitted by the Canadian Consumer Specialty Products Association, an industry association, a vehicle manufacturer, IBM Global Real Estate Canada, an individual, KG Industries Ltd., an aircraft engine manufacturer, the Tire and Rubber Association of Canada, and the U.S. Tire Manufacturers Association.

Summarized public comments and responses are provided below, organized by topic.

General comments

Comment summary 1: Some of the substances in the group are of interest to industry association members. The draft screening assessment was technically sound and clearly presented.

Response 1: Noted.

Comment summary 2: The draft screening assessment should have been published as 2 separate assessments because it appears the 2 sets of substances comprise somewhat different collections of uses and health and environmental properties, with the presence of a mercaptobenzothiazole (MBT) structure being an important consideration. 

Response 2: Despite certain structural similarities, the benzotriazoles and benzothiazoles differ in uses and other properties. The assessment was divided into 2 chapters to account for differences between the 2 sets of substances.

Comment summary 3: Certain substances in the group which were determined to be of low concern to both human health and the environment through other approaches are of interest to our industry association members.

Response 3: Noted.

Comment summary 4: Industry association members support the proposed conclusion in the draft screening assessment for the substances in the benzotriazoles subgroup. Uses of these substances include medicinal and industrial disinfectants and cleaners.

Response 4: Noted.

New information and data

Comment summary 5: 2 of the benzotriazole substances in the draft screening assessment are used in 6 cleaning chemicals.

Response 5: The potential exposure of the general population in Canada to these substances from cleaners is addressed in the assessment. Exposure to the Canadian environment is expected to be low for these benzotriazoles and others considered. No changes to the assessment were made.

Comment summary 6: Members of an industry association use MBT in industrial closed water systems or equipment cleaners, while SMBT is used in water treatment products, automotive products, closed water system industrial chemical treatment, and in a Drug Identification Number (DIN) registered disinfectant. Confirmation is requested that these uses are not of concern to human health or the environment and would not be considered in the scope for risk management actions.

Response 6: The known sources and uses for MBT and SMBT are identified in the assessment. The uses identified in the comment were considered in the development of the assessment but were not included as part of ecological scenarios of concern due to having smaller anticipated releases to the environment when compared to the other scenarios presented. The human health assessment is focused on exposures concerning the general population. The additional information received in the public comment and upon follow-up with the stakeholder did not suggest any additional exposures relevant to consumers in Canada. Sentinel exposure scenarios were calculated and presented in the assessment. As such, no changes to the assessment are necessary. The Government of Canada’s proposed risk management activities will focus on minimizing the ecological risks identified in the assessment based on available information.

Sources and releases

Comment summary 7: Benzotriazoles can be found in run-off from roads as a result of many applications. More data are required on the presence of these substances in road run-off, surface water, and roadside soils.

Response 7: The information referenced by the submitter aligns with information presented in the assessment on the known sources and uses of benzotriazoles and benzothiazoles. Releases from tire wear particles are unlikely to pose an ecological concern at the current level of exposure. However, the Government of Canada is proposing to monitor benzothiazoles in surface waters and sediment.

Comment summary 8: Benzothiazole, benzotriazole and several of their derivatives are used in textiles and are slightly soluble in water. As a result, clothing can be a potential source of human exposure to these chemicals, and laundering of textiles can be a source of their emission into the environment.

Response 8: The potential use of substances in the Benzotriazoles and Benzothiazoles Group in textiles was considered in the assessment. No changes to the assessment were made based on the information provided.

Environmental fate and behaviour

Comment summary 9: European research indicates the presence of ultraviolet (UV) stabilizers and UV filters such as benzotriazoles in northern marine sediments. More attention is required towards these substances. In particular, more sediment toxicity data are needed.

Response 9: Exposure to the Canadian environment is expected to be low for the benzotriazoles considered in the assessment. UV-360 and ethylhexyl triazone (EHT) were not included in the assessment, as they did not meet categorization criteria.

Comment summary 10: Benzotriazoles are emerging contaminants for which long-term research is required to fully assess their effects on aquatic biota, due to their bioaccumulative properties.

Response 10: Information provided by the submitter aligns with information presented in the assessment. Given the current use patterns of benzotriazoles in Canada, these substances are not expected to pose a concern for the environment at current levels of exposure. Assessments are based on the best available data. New information can be submitted through several mechanisms defined under specific sections of the Canadian Environmental Protection Act, 1999 (CEPA) and other legislation. All substances assessed under the CMP may be subject to future evaluation if new, significant information is received that indicates a need for further consideration.

Risk characterization

Comment summary 11: Additional transparency is needed in the analysis of environmental exposures for benzothiazoles. Environment and Climate Change Canada (ECCC) should collaborate with stakeholders to ensure that the assessment accurately represents environmental releases from tire manufacturing facilities.

Response 11: The assessment was revised to address comments from the stakeholders, including using appropriate emission factors and applicable removal rates for on-site pre-treatment, on-site secondary treatment, and off-site wastewater treatment systems for each tire manufacturing facility.

Comment summary 12: There is a need for additional transparency in 2 of the exposure scenarios for benzothiazoles presented in the draft screening assessment, specifically relating to parameters used to calculate the predicted environmental concentrations (PECs).

Response 12: Confidential business information, such as parameters specific to an individual facility, parameters that might reveal facility identity or location, or parameter values that may be used to back calculate other parameter values that are confidential business information, cannot be disclosed to the public. However, to increase transparency, more detail on the selection of parameters was added to the assessment and a new table was created to provide the parameter ranges that are used in the Monte Carlo simulations for Scenario 1.

Comment summary 13: Inappropriate emission factors were used in the draft screening assessment to calculate PECs for releases from tire manufacturing.

Response 13: Emission factors used in the assessment have been adjusted using ChemRisk 2010 and ECB 2003. In addition, all applicable removal rates for each tire manufacturing facility are used. Moreover, Monte Carlo simulations that consider applicable parameter ranges are used in the calculations. Additional clarification was added to the assessment.

Comment summary 14: The substance 2-MBT is a relevant allergen for workers, mainly in the rubber producing industry as well as in the general population. Skin lesions have been reported after contact with rubber and latex products that contained 2-MBT. 2 occupational exposure scenarios were identified for CBS. Occupational hazards should be taken into consideration for CBS, MBT, and precursors when developing risk mitigation steps.

Response 14: Assessments conducted under CEPA focus on risks of exposure of the general population, including disproportionately impacted population. Hazards related to chemicals used in the workplace are defined within the Workplace Hazardous Materials Information System (WHMIS).. The Government of Canada recognizes that it is the responsibility of the federal, provincial and territorial occupational health and safety organizations to coordinate legislation for the safe use of chemicals in the workplace. We are working to support this role by integrating the information, tools, and/or technical expertise of the CMP and Health Canada’s Workplace Hazardous Products Program.

Risk management

Comment summary 15: There are potential alternatives to certain substances in the benzotriazoles subgroup, and certain substances within the benzotriazoles subgroup are potential alternatives to other benzotriazoles. Some of these substances have faced phase-out pressures in Europe, as Candidate Substances of Very High Concern (SVHC) (2014).

Response 15: Identifying alternative chemicals or processes for use is not within the mandate of the CMP. However, in developing risk management approaches, the CMP considers substitutes and alternatives whenever possible and when adequate and relevant information is available on the economic, social and environmental implications for Canada. The assessment did not identify risks from the use of benzotriazole or benzothiazole substances in personal care products or textiles. As a result, no risk management is being proposed to address the use of these substances in personal care products or textiles. Reduction of and use of alternatives for UV stabilizers in personal care products and clothing should be studied further.

Comment summary 16: Textile use of benzothiazole and benzotriazole derivatives should be reduced to minimize the adverse impacts on the environment and human health. Awareness is required to avoid any allergy and adverse health effects. Labels and warnings should be added to personal care products and clothing.

Response 16: Risk assessments for substances under CEPA are based on best available data that represents a range of potential exposure scenarios in Canada. The assessment conclusion is based on conservative estimates of exposure that are protective of the Canadian public. The use of these substances in laundry and dishwashing scenarios was considered. The assessment did not identify risks from the use of benzotriazole or benzothiazole substances in personal care products or textiles. As a result, no risk management or labelling is being proposed to address the use of these substances in personal care products or textiles.

Comment summary 17: If the Government of Canada modifies the scope of the proposed risk management activities to include uses of benzothiazoles related to the industry association’s sector, the association wishes to re-engage as appropriate.

Response 17: Noted. The Government of Canada is committed to consulting with stakeholders as part of the risk management process.

Comment summary 18: The members of 2 industry associations provided their best practices to address potential releases of chemical substances, which would be applicable to the following activities: reception in the facility following delivery; storage; handling and dispensing; spills, leaks, releases (from all operations that occur in the facility); potential water contamination and industrial water disposal; packaging and shipping; maintenance; waste reduction; training.

Response 18: The information received was considered in the development of the risk management approach and, if appropriate, will be considered in the development of risk management instruments for MBT and its precursors.

Comment summary 19: An industry association supports the proposed risk management options for the Benzotriazoles and Benzothiazoles Group as long as they remain targeted at the exposure sources of concern identified in the Risk Management Scope. Risk management options must be carefully considered and designed, and should not limit access of consumers in Canada to other product applications and sectors whose products contain substances in the Benzotriazoles and Benzothiazoles Group. The industry association wishes to continue engaging with ECCC and Health Canada on the risk management of chemical substances.

Response 19: Noted. The Government of Canada’s proposed risk management activities will focus on minimizing the risks identified in the assessment based on available information. The Government of Canada is committed to consulting with stakeholders as part of the risk management process.

Consultation and/or stakeholder engagement

Comment summary 20: Submitter uses a substance included in the draft screening assessment and remains available should further information be required in the finalization of the assessment.

Response 20: Noted.

Comment summary 21: Stakeholder remains available should additional information, such as on DIN disinfectant products, be required to finalize the assessment and Risk Management Approach. Stakeholder wishes to be kept informed of any risk management activities.

Response 21: Noted. The Government of Canada is committed to consulting with stakeholders as part of the risk management process.

Comment summary 22: MBT and its precursors are used in the manufacturing sector by the stakeholder and its suppliers. If the Government of Canada prohibits or limits the use of these substances, substantial efforts will be required to find a replacement substance. Stakeholder wishes to be kept informed of any future risk management activities with regards to these substances.

Response 22: Noted. The Government of Canada is committed to consulting with stakeholders as part of the risk management process.

References

ChemRisk LLC. 2010. Tyre and general rubber good generic exposure scenario: Emission factor guidance for formulation and industrial use. Final report prepared for ETRMA. Pittsburgh (PA): ChemRisk LLC. 33 pages.

[ECB] European Chemicals Bureau, Institute for Health and Consumer Protection. 2003. Technical guidance document on risk assessment, part II. Luxembourg City (LU): European Chemicals Bureau. 337 pages.