p-Toluenesulfonic acid - Information sheet

Benzenesulfonic acid, 4-methyl- (PTSA)
CAS Registry Number 104-15-4

Publications summarized:

• Final Screening Assessment for Benzenesulfonic acid, 4-methyl- (p-Toluenesulfonic acid) (published on June 18, 2022). Public comments received on the draft screening assessment were considered and a summary was published.
• Associated notice: Canada Gazette, Part I: Vol. 156, No. 25 – June 18, 2022

On this page

• Overview
• About this substance
• Human and ecological exposures
• Key health and ecological effects (hazard)
• Consideration of vulnerable populations
• Risk assessment outcomes
  • Screening assessment conclusions
• Related resources

Overview

• 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 or 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 ecological hazard and exposure potentials of this substance were classified using the Ecological Risk Classification of Organic Substances (ERC) Approach.
• p-Toluenesulfonic acid (PTSA) is considered to have a low health hazard potential. At levels of exposure considered in the assessment, the Government concluded that PTSA is not harmful to human health or to the environment.

About this substance

• The screening assessment focused on PTSA, also referred to as benzenesulfonic acid, 4-methyl-. It was assessed under the third phase of the Chemicals Management Plan (CMP).
• PTSA does not occur naturally in the environment.
• According to information gathered by the Government, PTSA is mainly used in Canada in the manufacture of paints and coatings, and of plastic and rubber materials, among other uses.

Human and ecological exposures

• The screening assessment indicated that Canadians may be exposed to PTSA from the use of an adhesive for crack repair of structural materials (including concrete and wood), certain varnish sprays for interior wood furnishings, and cosmetics, such as face lotion, hair dye, and hair conditioner.
• According to the information considered under the ERC Approach, PTSA was identified as having a low ecological exposure potential.

Key health and ecological effects (hazard)

• There were limited health effects (hazard) data for PTSA; therefore, a comparative approach using similar chemicals, called read-across, was used for assessing potential health effects.
• To identify health effects information, international reports were considered. This included an assessment of hydrotropes, which included salts of PTSA, by the Organisation for Economic Cooperation and Development Cooperative Chemicals Assessment Programme.
• On the basis of considerations set out in the Science Approach Document for Substances with Low Human Health Hazard Potential, PTSA is considered to have a low health hazard potential.
• According to information considered under the ERC Approach, PTSA was identified as having a low ecological hazard potential.

Consideration of vulnerable populations

• There are groups of individuals within the Canadian population who, due to either greater susceptibility or greater exposure, may be more likely to experience adverse health effects from exposure to substances.
• Certain subpopulations are routinely considered throughout the screening assessment process, such as infants, children, and people of reproductive age. For PTSA, these populations were taken into account in the risk assessment outcomes.

Risk assessment outcomes

• On the basis of the information presented in the screening assessment, the risk to human health from PTSA is low.
• Based upon the outcome of the ERC Approach, PTSA is considered unlikely to be causing ecological harm.

Screening assessment conclusions

• The Government concluded that PTSA is not harmful to human health at levels of exposure considered in the assessment.
• The Government also concluded that PTSA is not entering the environment at levels that are harmful.

Related resources

• PTSA may be found in products available to consumers. Canadians should follow any safety warnings and directions related to the product and dispose of products responsibly.
• The screening assessment focused on potential risks from exposure of the general population of Canada, rather than occupational exposure. Hazards related to chemicals used in the workplace are defined within the Workplace Hazardous Materials Information System (WHMIS). For information concerning workplace health and safety and what steps to take in the workplace, Canadians should consult their employer or the Occupational Health and Safety Regulator in their jurisdiction.