Non-pesticidal uses of six substances on the Domestic Substances List - information sheet

Updated March 17, 2021:

The Final Screening Assessment of 6 Substances on the Domestic Substances List Associated with Pesticidal Uses was published in August 2009 under the Chemicals Management Plan (CMP). The assessment is summarized in this information sheet and has not changed. The section in this information sheet entitled "Preventive actions and reducing risk" communicates updates in risk management activities, namely:

An amendment to the Domestic Substances List (DSL) to change the requirements for these substances under the Significant New Activity (SNAc) provisions of the Canadian Environmental Protection Act, 1999 (CEPA 1999).

The Government of Canada conducted a science-based screening assessment under the Canadian Environmental Protection Act, 1999 (CEPA 1999) to address the potential for harm to Canadians and to the environment from the non-pesticidal uses of 6 substances.
The risk posed by a substance is determined by considering both its hazardous properties (its potential to cause adverse human health or ecological effects) and the amount of exposure there is to people and the environment.
As a result of the screening assessment, the Government concluded that these 6 substances are not harmful to human health or to the environment, at levels of exposure considered in the assessment. Although these substances are associated with human health and/or ecological effects of concern, it was determined that the risk posed by these substances to Canadians and to the environment from non-pesticidal uses is low at levels of exposure considered in the assessment.

The screening assessment summarized here focused on 6 substances on the DSL that are known to be used as active ingredients in pesticidal applications. These substances are commonly referred to as methoxychlor, pentachlorophenol, trifluralin, chlorothalonil, atrazine, and chlorophacinone. They were assessed under the CMP.
According to information gathered by the Government, at the time of the assessment, 5 of the 6 substances (pentachlorophenol, trifluralin, chlorothalonil, atrazine, and chlorophacinone) were used in Canada in pest control products regulated by Health Canada's Pest Management Regulatory Agency (PMRA) under the Pest Control Products Act (PCPA).
Use of methoxychlor in pesticides in Canada ended in December 2005, and no other uses were identified for this substance.
Health Canada, as required under the PCPA, re-evaluates all registered pesticide products on a 15-year cycle to determine whether the use of these products continues to be acceptable according to current standards.

Exposure of Canadians and the environment from non-pesticidal uses of these substances was not expected, since no such uses in Canada were identified at the time of the assessment.
Any releases to the environment from pesticidal uses associated with these 6 substances have been assessed under the PCPA.

Four of the 6 substances (pentachlorophenol, trifluralin, chlorothalonil, and atrazine) are considered to have human health effects of concern, based upon their potential carcinogenicity.
All 6 substances are associated with ecological effects of concern, based upon their potential to harm animals and/or plants in the environment.

Based upon the information presented in the screening assessment, exposure of Canadians from non-pesticidal uses of these 6 substances is not expected; therefore, the risk to human health is considered to be low.
Considering all information presented, it was determined that there is low risk of harm to the environment from non-pesticidal uses of these substances.
The Government of Canada published the Final Screening Assessment of 6 Substances on the DSL Associated with Pesticidal Uses on August 8, 2009.

The Government concluded that non-pesticidal uses of these 6 substances are not harmful to human health, at levels of exposure considered in the assessment.
The Government also concluded that these substances are not entering the environment from non-pesticidal uses at levels that are harmful to the environment.

Methoxychlor, pentachlorophenol, trifluralin, chlorothalonil, atrazine, and chlorophacinone are subject to the SNAc provisions of CEPA 1999. This requires that the Government be notified of certain proposed new activities related to these substances, and that the new activity be assessed for potential risks to human health and the environment before being undertaken.
On March 17, 2021, the SNAc publication for methoxychlor, pentachlorophenol, trifluralin, chlorothalonil, atrazine, and chlorophacinone was amended as a result of the Government's review of current SNAc orders and notices. This update included changes to the definition of a SNAc in relation to these substances, as well as changes to the data elements required by the Government for assessment.

The pesticidal uses of atrazine, chlorophacinone, trifluralin, and pentachlorophenol have been re-evaluated under the PCPA by Health Canada's PMRA. These uses will continue to be permitted with risk reduction measures. Under the PCPA, special reviews on chlorothalonil, atrazine and pentachlorophenol are currently underway.
All pesticidal uses of methoxychlor were discontinued and all registrations expired as of December 31, 2005; therefore, there are no pesticidal uses of this substance permitted in Canada.
Some of these substances 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 for these 6 substances focused on potential risks of exposure to 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 and/or the Occupational Health and Safety Regulator in their jurisdiction.