The risks posed by a substance are determined both by 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.
Amitrole, NaDCC, and hexa(methoxymethyl)melamine may be associated with health effects; however, at levels of exposure considered in the assessment, the Government concluded that they are not harmful to human health or the environment at levels of exposure considered in the assessment.
Another substance (CAS RN 121-82-4) will be assessed in another screening assessment.
The 3 substances in this group are not expected to occur naturally in the environment. According to information gathered by the Government, amitrole is registered in Canada as a herbicide; however, these products are in the process of being discontinued.
NaDCC may be used in a variety of products, such as water treatment products, cleaning products, and disinfectants. It is also an active ingredient in pest control products.
Hexa(methoxymethyl)melamine may be used in the manufacture of food packaging materials. It may be used in commercial products, such as paints and coatings as well as in automotive, aircraft and transportation applications.
Human and ecological exposures
Exposure of Canadians to amitrole is not expected, based upon the uses of the substance identified in the screening assessment.
Canadians may be exposed to:
NaDCC mainly from the use of products available to consumers, such as water treatment tablets and cleaning abrasive powders.
Hexa(methoxymethyl)melamine from its potential presence in drinking water. Exposure to this substance from food packaging is expected to be negligible.
According to information considered under the ERC Approach, amitrole and NaDCC were identified as having low ecological exposure potential; however, hexa(methoxymethyl)melamine was classified as having a high ecological exposure potential due to its overall persistence and use quantities reported to the Government.
There were limited health effects (hazard) data for NaDCC and hexa(methoxymethyl)melamine; therefore, a comparative approach using similar chemicals, called read-across, was used for assessing potential health effects. Using data available for similar substances, the critical effects identified for these substances from laboratory studies were:
for NaDCC, effects on the urinary tract and heart, and
for hexa(methoxymethyl)melamine, effects on the bladder, urinary system and possible carcinogenicity.
According to information considered under the ERC Approach, amitrole and hexa(methoxymethyl)melamine were identified as having low ecological hazard potential, while NaDCC was identified as having a high ecological hazard potential based on its reactivity and ecotoxicity.
Risk assessment outcomes
As exposure of Canadians to amitrole is not expected, the potential risk to human health is considered to be low.
The risk to human health from NaDCC and hexa(methoxymethyl)melamine is also considered to be low, based upon a comparison of levels to which Canadians may be exposed to these substances, and the levels associated with health effects, along with the consideration of international assessments.
Based upon the outcome of the ERC Approach, these 3 substances are considered unlikely to be causing ecological harm.
Screening assessment conclusions
The Government concluded that amitrole, NaDCC, and hexa(methoxymethyl)melamine are not harmful to human health at levels of exposure considered in the assessment, and that these 3 substances are not entering the environment at levels that are harmful.
Preventive actions and risk reduction
Although a risk to human health or the environment has not been identified at current levels of exposure, there may be a concern if exposures to amitrole or to hexa(methoxymethyl)melamine were to increase. As a result, these substances may be considered in future initiatives to track their commercial status or identify new uses.
Use the Substances Search tool to find substances that are referenced in certain legislative or regulatory instruments or on Government of Canada websites.
Related resources
In 2018, Health Canada's PMRA initiated a special review of amitrole. All pest control products containing amitrole are now being discontinued, and the special review of amitrole is closed.
NaDCC 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 and/or the Occupational Health and Safety Regulator in their jurisdiction.
