Summary of public comments received on the draft screening assessment and risk management scope for talc

The draft screening assessment undermines the credibility of, and fails to deliver on, the three pillars of the Chemicals Management Plan (CMP):  sound science, due process, and effective communication to Canadians.

Significant process issues have been identified with the draft screening assessment and it was not completed in compliance with section 76.1 of the Canadian Environmental Protection Act, 1999 (CEPA), respecting the application of weight of evidence and precautionary principle. A more thorough weight of evidence approach is recommended.

The screening assessment for talc is based on the best and most relevant available data and applied both weight of evidence and precaution in a manner consistent with their application under the CMP.

A weight of evidence approach was applied, consistent with other screening assessments conducted under CEPA, including gathering available and relevant information, evaluating and combining multiple lines of evidence, and determining whether the substance may pose a risk to human health or to the environment. Additional text was added to the final screening assessment in consideration of stakeholder comments to enhance transparency with respect to the data, approach and assumptions used in the assessment.

Applying precaution in risk assessment means using conservative but realistic assumptions to account for the uncertainty identified at various stages of an assessment. Precaution is applied as appropriate to ensure the approach is protective of human health and the environment.

Further information on how the program applies weight of evidence and precaution under the CMP can be found here.

The draft screening assessment does not consider all the available evidence and is not transparent in the assumptions used to support the conclusion.

To ensure that the regulatory decision-making process is scientifically sound, additional details regarding the risk assessment approach, the evidence identified and assessed, and the evaluation of the weight of evidence in the draft screening assessment should be provided.

The best and most relevant available data on the potential human health effects of talc, exposure of the general population, ecological hazard and ecological exposure were considered. All information identified and submitted by stakeholders was considered when updating the screening assessment. The screening assessment does not list or describe all available data, but rather presents only the relevant information key to the risk characterization.

The level of detail provided in the screening assessment is consistent with other screening assessments conducted under the CMP. Nevertheless, additional text was added to the final screening assessment in consideration of stakeholder comments to increase transparency with respect to the data, approach and assumptions used in the assessment.

The draft screening assessment does not follow Canada’s own guidance for risk evaluations and deviates from best scientific practices. It is recommended that Health Canada return to its usual practices, when screening substances, to inform its conclusions with rigorous science that has undergone peer review.

The scientific approach used in this assessment is consistent with other screening assessments published under the CMP, as described in the risk assessment toolbox. The de novo assessment used a fit-for-purpose approach that considered both hazard and exposure and multiple lines of evidence. Further information on the risk assessment process under the CMP can be found here. The screening assessment underwent both internal and external peer review prior to publication. 

Stakeholder engagement was undervalued.

Consistent with the underlying principles of CEPA, there was ample opportunity for and extensive engagement by stakeholders on the talc draft screening assessment. In addition to the 60-day public comment period, a number of meetings took place between 2013 and 2020 with a range of stakeholders, and submitted information was taken into consideration.

It is recommended that Health Canada revisit its analysis and consider all evidence, including comments received during the 60-day public comment period.

The public comment period is an important step in the risk assessment process as it is the opportunity for interested parties to provide feedback on the assessment. All information identified and submitted by stakeholders was considered when updating the screening assessment. Additional text was added to the final screening assessment in consideration of stakeholder comments to increase transparency with respect to the data, approach and assumptions used in the assessment.

A stakeholder questioned whether tailings around former Canadian talc mines are a public health hazard and if this would affect the conclusion that talc is not entering the environment at levels that are harmful to the environment.

The risk to human health from airborne talc around former talc mines was not identified to be of concern.

The conclusion that talc is not entering the environment at levels that are harmful to the environment was reached using a risk-based approach that considers both hazard and exposure. Specific concentration data on tailings from existing or former talc mines are lacking. However, talc was identified as having both a low hazard and a low potential for exposure to non-human ecological receptors (e.g., fish, invertebrates, algae).

The screening assessment lacks transparency about the focus on cosmetic-grade talc and why engineered nanomaterials are not explicitly considered.

The assessment focused on certain self-care products containing cosmetic- or pharmaceutical-grade talc because the use of these can result in inhalation and perineal exposure, for which critical health effects were identified.

Inhalation exposure of the general population from industrial and commercial uses of talc, which may contain lower-grade talc, was also considered in the screening assessment but was not identified to be of concern to human health as the number of industrial and commercial sites producing and processing talc in Canada is limited. Therefore, talc exposure from ambient air is not expected to be significant.

Respirable-sized talc particles have been found in self-care products. There is limited information on the presence of smaller nano-sized particles in self-care products. One Health Canada study (Rasmussen et al. 2019) measured respirable talc particles (< 4 µm) in four self-care products with little to no talc particles in the nano range (< 0.1 µm or 100 nm).

Stakeholder is pleased that the draft screening assessment reflects the fact that talc is not asbestos and is morphologically very different from asbestos.

Noted.

The draft screening assessment fails to incorporate findings of occupational hazards of talc, including mortalities in workers due to lung diseases following exposures to talc.

Screening assessments conducted under CEPA focus on risks of exposure to the general population, rather than risks of exposure in the workplace. Hazards related to chemicals used in the workplace are defined within the Workplace Hazardous Materials Information System (WHMIS).

The Government of Canada is currently working with the provinces and territories to explore ways to enhance the protection of workers from exposure to chemicals by integrating and leveraging the information, tools, and/or technical expertise of the CMP and Health Canada’s Workplace Hazardous Products Program. For more information, please visit: An Integrated Strategy for the Protection of Canadian Workers from Exposure to Chemicals.

There are gaps in the assessment that fail to acknowledge gender-based considerations. The use of pressed powders daily, and in combination with other talc self-care products, results in a gender-specific exposure and should be considered in the assessment.

Sex and gender considerations are incorporated into screening assessments as part of the consideration of susceptible sub-populations. In this assessment, women are considered susceptible to one of the identified critical health effects, ovarian cancer. The inhalation effects are relevant for all sexes and genders. The best and most relevant available exposure information relating to the use of self-care products, including pressed powders, in different populations was incorporated into the exposure estimates.

There are gaps in the assessment that fail to acknowledge risks of asbestos contamination. Though the assessment notes that “cosmetic-grade talc should comply with United States Pharmacopeia (USP) standards” and that “in 1976 the Cosmetic Toiletry Fragrance Association (CTFA) set purity standards for cosmetic-grade talc”, these voluntary untested standards have been challenged by product testing in recent talc litigation cases.

In Canada, asbestos is prohibited above trace levels in products available to consumers, including cosmetics, under the Prohibition of Asbestos and Products Containing Asbestos Regulations of CEPA.

The screening assessment focused on exposure from use of cosmetic-grade talc, which should comply with USP standards and be free of asbestos according to those standards. The purity standards established by the CTFA in 1976 led to a reduction in the levels of asbestos contamination in cosmetic products. The USP standard for talc is currently under review and the United States Food and Drug Administration (U.S. FDA) is working on recommendations on testing methods for asbestos in talc and products available to consumers containing talc.

The best and most relevant available data on the potential human health effects of talc and exposure of the general population were considered. The screening assessment does not list or describe all available data, but rather presents only the relevant information key to the risk characterization.

The NTP (1993) study used talc with a median mass aerodynamic diameter (MMAD) (2.7 to 3.2 μm), which is more closely aligned with the particle size in finished productsthan the study by Wehner et al. (1977; MMAD 6.0μm). The NTP study was therefore considered more relevant than the Wehner study for characterizing hazard associated with self-care products containing talc.

The NTP study used the appropriate test substance (in terms of particle size), was well conducted and was thoroughly reported. Other available studies were conducted with only one dose, had limited parameters examined/reported and used a test substance with a larger particle size, which would be cleared from the lungs by different mechanisms. Limitations with these studies precluded their use in endpoint selection.

All information identified and submitted by stakeholders was considered when updating the screening assessment. Additional text was added to the final screening assessment in consideration of stakeholder comments to enhance transparency with respect to the data, approach and assumptions used in the assessment.

Cosmetic talc products are formulated to be largely non-respirable and therefore do not present an inhalation risk.

Talc particle size, lung overload, and toxicokinetics of poorly soluble particles were taken into consideration in the screening assessment.

Particle size measured in various self-care products indicate that the majority of the particles are well within the respirable range(≤ 4 µm), with a large proportion expected to deposit deep within the lung. This is noted in the screening assessment and was taken into account when evaluating the relevance of studies to the assessment.

Lung retention half-lives for poorly soluble particles in general are estimated in the scientific literature at 70 and 400 days in rats and humans, respectively. For recurring exposures in humans, only minimal clearance would have occurred between daily (or weekly) exposures, as the rate of deposition is higher than the rate of clearance, unless exposures are very infrequent.

The level of detail provided in the screening assessment is consistent with what is typically presented in a screening assessment. Available information on particle size in self-care products is cited in the screening assessment.However, additional text was added to the final screening assessment in consideration of stakeholder comments toenhancetransparency with respect to the data, approach and assumptions used in the assessment.

The draft screening assessment does not consider all the available human epidemiological data regarding health effects from inhalation exposure to talc. Although the no observed adverse effect concentrations (NOAECs) from the epidemiology studies cannot be used in a quantitative exposure/risk assessment because they are long-term exposure values obtained directly from human populations, they reduce the uncertainty associated with the use of a point-of-departure (POD) identified from an animal toxicity study.

Similar NOAECs in humans and rodents, in combination with dosimetry modeling results, provide support that the interspecies uncertainty factor (typically a value of 10) is not warranted for the risk assessment of talc inhalation exposure.

The best and most relevant available data on the potential health effects of talc in animals and humans were considered.

In 2016, the Danish Environmental Protection Agency (EPA), another regulatory body, established a health-based quality criterion for talc in ambient air, based on both animal and human data. They considered a lowest observed adverse effect concentration (LOAEC) from a chronic animal study and used a human study to derive both animal and human PODs for lung effects. Limitations with the human study, including a follow-up period considered too short, resulted in the use of an additional uncertainty factor. After incorporating uncertainty factors of 250 (2.5-fold interspecies x 10-fold intraspecies x 10-fold use of a LOAEC) for the animal endpoint and 100 for the human endpoint (1-fold interspecies x 10-fold intraspecies x 10-fold database uncertainty) to address inherent uncertainties within the database, the Danish EPA arrived at similar values for their air quality criterion, regardless of whether an animal or human POD was chosen.

The screening assessment does not list or describe all available data, but rather presents only the relevant information key to the risk characterization. All information identified and submitted by stakeholders was considered when updating the screening assessment. Additional text was added to the final screening assessment in consideration of stakeholder comments to enhance transparency with respect to the data, approach and assumptions used in the assessment.

The screening assessment should clearly establish what is considered to be an acceptable margin of exposure (MOE).

A target MOE of 25 should be considered to be adequately protective of local lung effects based on a 10-fold uncertainty factor for intraspecies variability and a 2.5-fold uncertainty factor for interspecies extrapolation for local lung effects.

The acceptability of a MOE is determined by considering many factors, such as the inherent hazard of the substance and severity of health effects, the route, frequency and duration of exposure in a critical animal study, and human exposure relative to the POD selected.

MOEs must be adequate to address uncertainties in the health effects and exposure database. Considerations may include uncertainties associated with extrapolating a POD for long-term exposure from a study of shorter duration, extrapolating from a LOAEC to a NOAEC when there is lack of a clear POD due to adverse effects observed at all doses, taking into account the steepness of the dose response, and limitations in the critical study and/or supporting database.

In this case, the target MOE of 25 suggested by the stakeholder does not fully account for uncertainties associated with extrapolating a POD for long-term exposure from a study of shorter duration, variability between species, or limitations in the supporting database.

The level of detail provided in the screening assessment is consistent with other screening assessments conducted under the CMP. Additional text was added to the final screening assessment in consideration of stakeholder comments to enhance transparency with respect to the data, approach and assumptions used in the assessment.

The totality of the data does not support an inhalation risk from the intended normal use of talc body powders. The risk has already been reviewed by the Cosmetic Ingredient Review (CIR) Expert Panel and any potential non-cancer risks are mitigated by current label warnings.

As noted in the screening assessment, Health Canada reviewed the CIR Expert Panel review, as well as evaluations from other groups and jurisdictions, and considered its findings when developing the screening assessment.

Respirable talc concentrations measured in exposure studies during typical use of talc self-care products resulted in MOEs that were considered potentially inadequate to address uncertainties in the health effects and exposure database. The current label statements are insufficient to mitigate inhalation risks to the general population.

There are no health effects of talc that are inherent to its chemistry; effects noted are primarily due to the presence of an inert foreign particle.

Post-market analysis of talc self-care products showed that case reports of inhalation of talc powder resulted in respiratory effects including difficulty breathing, chemical bronchitis, cough, shortness of breath and wheezing.

There was no rationale provided for the critical studies used in the inhalation exposure estimates, specifically the use of air concentration data from the Anderson et al. (2017) and Rasmussen et al. (2019) studies and the exclusion of air concentration data from older studies (Aylott et al. 1979, Russell et al. 1979). Some stakeholders felt there was an over-reliance on the Rasmussen et al. (2019) data as it was an unpublished study, and others felt there was an under-reliance on the Rasmussen et al. (2019) data and that it should be the sole study.

Some stakeholders commented that air concentration data by product type (e.g., baby powder, body powder, face powder) presented in Aylott et al. (1979) and Russell et al. (1979) should have been used to generate product specific inhalation estimates.

Screening assessments under the CMP make use of the best and most relevant available data including information in draft manuscripts available prior to their publication if considered relevant to the assessment. The Rasmussen et al. study (2019) cited in the draft screening assessment and referred to in the public comments has since been published in a peer-reviewed journal and can be found here.

Aylott et al. (1979), Russell et al. (1979), Anderson et al. (2017) and Rasmussen et al.(2019) were all reviewed along with other exposure studies measuring air concentrations. Anderson et al. (2017) and Rasmussen et al. (2019) are considered to be the best and most relevant available data for quantifying inhalation exposure. There are uncertainties associated with the talc concentrations presented in the Aylott et al. (1979) and Russell et al. (1979) studies resulting from the useof older personal air sampling and cyclone collecting equipment and methods to quantify the concentration of talc in air at that time.

The level of detail provided in the screening assessment is consistent with other screening assessments conducted under the CMP. Additional text was added to the screening assessment in consideration of stakeholder comments to enhance transparency with respect to the data, approach and assumptions used in the assessment.

There was insufficient data to generate average air concentrations by product type, so data from the Anderson et al. (2017) and Rasmussen et al. (2019) studies were combined and used for all product types.

The draft screening assessment does not consider all the available data with respect to animal evidence, epidemiology evidence and mode of action. Evidence collectively indicates a lack of retrograde transport to the ovaries with no definitive evidence that perineal talc use is associated with the presence of talc in ovarian tissues. The draft screening assessment does not properly apply a weight of evidence approach, including proper application of the Hill considerations, to evaluate a potential causal association between perineal exposure to talc and ovarian cancer. The overall evidence does not support a causal relationship between perineal talc exposure and ovarian cancer.

A stakeholder offered a possible alternative mechanism to challenge the theory that inflammation plays a prominent role in ovarian tumour formation.

Screening assessments under the CMP make use of the best and most relevant available data including information in draft manuscripts available prior to their publication, or data extracted from internal databases, if considered relevant to the assessment. In addition, the screening assessment undergoes extensive peer review prior to publication.

The paper cited in the public comment has since been published in a peer-reviewed scientific journal which can be found here. Since the publication of the draft screening assessment, additional information provided by stakeholders was evaluated and considered and updates were made to the final screening assessment. Additional details on the evaluation of causation were added to the screening assessment to enhance transparency with respect to the data, approach and assumptions used in the assessment.

As noted in the screening assessment, Health Canada reviewed the CIR Expert Panel review and considered its findings when developing the screening assessment. All information identified and submitted by stakeholders was considered when updating the screening assessment. Additional details on the evaluation of causation were added to the final screening assessment to enhance transparency with respect to the data, approach and assumptions used in the assessment.

The final screening assessment does not list or describe all available data, but rather presents only the relevant information key to the risk characterization.

The available data with respect to perineal exposure are indicative of a causal relationship between genital talc use and ovarian cancer. The determination that the use of talc in certain self-care products could result in the potential for harm to human health was based on an assessment of risks following inhalation and perineal exposure. In consideration of this information, it is concluded that talc meets the criteria set out in section 64(c) of CEPA.

All information identified and submitted by stakeholders was considered when updating the screening assessment. Additional details on the evaluation of causation were added to the final screening assessment to enhance transparency with respect to the data, approach and assumptions used in the assessment.

Additional information related to the science regarding talc use and ovarian cancer was submitted by stakeholders.

Some of this additional information included documents either presented at meetings that took place between a group of stakeholders and Health Canada in April 2019 and July 2020, or submitted in response to questions posed at those meetings.

As a result of the human health risk assessment, it was determined that inhalation and perineal exposure to talc from the use of certain self-care products represents a potential concern for human health.

The MOEs between the air concentration of talc when using certain loose powder self-care products and levels associated with non-cancer lung effects, which may lead to a decrease in lung function, were potentially inadequate to account for uncertainties in the health effects and exposure database. With respect to perineal exposure, the available data are indicative of a causal relationship between genital talc use and ovarian cancer. In consideration of this information, it is concluded that talc meets the criteria set out in section 64(c) of CEPA.

The Talc - information sheet provides a summary of the key risk assessment and risk management information for the substance and is intended for informed stakeholders. The ‘Preventive actions and reducing risk’ section may be updated to communicate updates in risk management activities, as needed. Information and advice for consumers is provided on the Talc webpage.

Assessments under the CMP focus on exposure to the general population, rather than exposures in the workplace. Hazards related to chemicals used in the workplace are defined within the Workplace Hazardous Materials Information System (WHMIS).

The Government of Canada has various mechanisms available to monitor new information on substances and the potential for substitution. They include: mandatory notification requirements for cosmetic products and pre-market safety reviews of health products under the Food and Drugs Act, and notification requirements for new substances (including nanomaterials) under CEPA.

The Government of Canada is also exploring ways to advance responsible replacement of chemicals of concern, including ways to apply informed substitution to support chemicals management (Combined government discussion paper and science committee report on informed substitution, published August 28, 2018).

A consistent instrument selection process that includes environmental, health and socio-economic considerations is followed to select the most promising instrument (or mix of instruments) to manage risks associated with a toxic substance.

The proposed risk management will therefore focus on the scenarios and products of concern. As noted in the screening assessment, there is no evidence to suggest that talc is currently being used as a dry lubricant on medical examination gloves in Canada. At present, powdered gloves are not considered to be a source of perineal exposure; therefore, risk management for this use is not warranted.

Stakeholder is concerned with how the Government of Canada has already begun communicating the potential human health risks prior to finalizing the screening assessment. This action presupposes the outcome of the public consultation, which may result in a different outcome and unnecessary consumer confusion.

Meaningful public communications need to be prepared to replace current documents.

Stakeholder is concerned that the draft finding was communicated publicly in a very proactive and alarming way, including through a misleading infographic and Healthy Home campaign. Communications are only warranted based on a final and clear conclusion that is reached following appropriate consultation and based on sound science.

The communications campaign has caused irreparable harm to the industry and should have only been undertaken following a final conclusion based on the weight of scientific evidence.

The Government of Canada’s Regulatory Openness and Transparency Framework and Action Plan acknowledges that Canadians want to make informed decisions about their and their families’ health. Health Canada provides Canadians with information on health and safety issues to support their decision-making and increase opportunities for engagement. This can include making scientific and regulatory information available to Canadians in plain language, including at the draft screening assessment stage.

The Government of Canada commits to openness and transparency with all Canadians, and part of that is alignment with the Directive on the Management of Communications. The plain language summaries and infographic help meet the diverse information needs of the public by enabling that not only those with high technical literacy can access information that may impact the public (e.g., information on substances or products that may be harmful to human health).

Communications products for talc may be updated as needed moving forward.

While transparency is an essential element of Canada’s CMP, it is equally essential that information shared widely through media releases, infographics, and on government websites be thoroughly reviewed through rigorous processes for veracity and accuracy.

One of the primary reasons for publishing draft reviews is to give stakeholders, including academics, industry, and consumers, an opportunity to provide additional information that could impact a proposed conclusion.

Only once a draft screening assessment and accompanying risk management proposal have been thoroughly reviewed and finalized should the government publish tools like an infographic and include general statements on consumer webpages.