7 May: Canada consultation borate risks
Draft assessment concludes possible environment and health risks from cumulated natural and anthropogenic sources. The draft risk assessment and scope open for consultation is an update of a 2016 screening assessment and risk scope.
The assessment focuses on boric acid, as relevant moiety included in borate salts and potentially released by boron compounds. It is noted that boric acid has both natural and anthropogenic sources. Natural sources include biomass burning, plant aerosols, rock and soil weathering. Background concentrations are c. 10 mg/kg (natural occurrence) in the earth’s crust. Boron is an essential micronutrient for most plants and some animals, so uses include in fertilisers. It is also present in cosmetic and natural health care products. Anthropogenic sources include wood processing, mining and minerals extraction, metal processing, fossil fuel burning. Boron compounds are used in, amongst others, adhesives, paints and coatings, water treatment, lithium ion batteries, and flame retardants
Environmental concentrations (PEC) are calculated for local releases for activities such as mining, wastewater releases and several industrial processes which use boron compounds (rubber manufacturing, electroplating, fibreglass, pulp and paper). This concludes “low potential for ecological harm from most sectors and activities that release boric acid”.
Boric acid is a metalloid ion so is considered by nature to be “infinitely persistent”, but is not generally bioaccumulative and does not biomagnify. Boron can be (eco)toxic at excessive levels of exposure and the draft assessment concludes that it:
- meets the criteria of section 64(a) part 5 of CEPA (Canada Environment Protection Act): “have or may have an immediate or long-term harmful effect on the environment or its biological diversity”;
- does not meet the criteria of section 64(b): “constitute or may constitute a danger to the environment on which life depends”;
- meets the criteria of section 64(c): “constitute or may constitute a danger in Canada to human life or health”
The draft risk scope proposes actions on boric acid use in flame retardants (in particular in mattresses and futons), cleaning products, swimming pool and spa products and DIY products, arts – crafts, toys, cosmetics, natural health products and non-prescription drugs and one metal ore processing site.
“Updated draft assessment - Boric acid, its salts and its precursors”, Health Canada March 2025 LINK.
“Revised risk management scope for boric acid, its salts and its precursors”, Health Canada March 2025 LINK.
Canada CEPA “Moiety approach” LINK.
Public consultation on updated draft assessment and scope, open to 7th May 2025 https://gazette.gc.ca/rp-pr/p1/2025/2025-03-08/html/notice-avis-eng.html#nl1
