Ongoing Challenges for Sustainable Water-based Paint in Canada

The issue of biocides in paint, and the increasingly tight regulation of them, has been gathering steam in Europe, Canada and the United States. It is among the top issues for the coatings industry. Until now, regulators have long been focused on the review and subsequent regulation for its many uses in crop protection, sanitization, etc. It has recently become clear that the more restrictive evaluation of uses for paint and coatings has not been well understood by regulators and thus challenging for the paint and coatings industry. CPCA’s extensive advocacy efforts continue to address this urgent matter, which seeks greater alignment with the United States in a highly integrated paint and coatings value chain.

The most recent evidence of those challenges was the ban of a very common biocide for paint and coatings use in Canada in 2019, OIT. The ban was reversed a year later in 2020. However, it is unclear why the same data used to restore both OIT as well as previous use levels for CMIT/MIT in Canada, produced a different than in the United States. CPCA never understood why the ban occurred in the first place given the fact there was strong scientific data provided for the re-evaluation and approval of OIT at existing label use rates in Canada. While the ban reversal was positive, it had already caused unfortunate disruption for the coatings industry and the formulations for many product lines on both sides of the border.

There is currently a cluster of critical biocides that protect paint products under re-evaluation in Canada. Final decisions for those biocides are imminent and it is now clear there will be severe use restrictions imposed on most of them including two outright bans. That is if further action is not taken by industry now. If not those critical ingredients will be taken out of the mix of options for paint formulation in Canada and will it affect product performance, consumer choice and ultimately price. Yet, they will still be available to manufacturers and consumers in the United States. However, products shipped to Canada from the United States will also have to be reformulated or taken of the market. It is unclear why this re-evaluation – using the exact same science – will produce a much different result in Canada.

Often overlooked by evaluators is the fact that biocides used in paint and coatings are very good examples of how microbial control technology is used effectively to preserve a material itself, stabilizing paint throughout its production, transportation and storage – before application. It also provides stability after application by protecting the structures on which it is applied such as wood coatings. Today there is a growing demand for paint with lower VOC emissions. This has led to the removal of solvents in architectural or decorative paint with very low to near Zero VOC water-based paint widely used by consumers. However, these products also require more intensive care to protect the integrity of the waterborne product in its final form, which can only be provided by biocides in the absence of solvents. In the process this has substantially reduced low-level emissions from coatings in Canada! Paint related emissions in Canada have been greatly reduced by more than 41 kilotons over the past 15 years. That is the equivalent of taking 3,280,000 cars of the road annually. 

The move to water-based paints, due to huge company investments in innovation, has further contributed to the sustainability of paint and coatings. Such technology advances has led to the paint industry’s impressive success in paint recycling across Canada. Last year more than 28 million kilograms of paint was recycled, enough to paint more than 500,000 homes. More than 94 percent of paint litreage sold in Canada is water-based architectural paint with very low or near Zero VOC emissions constituting a substantial share of those sales. The percentage of waterborne paint used for commercial purposes such as in automotive refinishing has also improved and now exceeds more than 30% of total sales in that segment, with more expected in the coming years.

The fact remains that without the use of biocides, also referred to as in-can preservatives, water-based paints would very quickly deteriorate in the can. Without dry-film preservatives, the paint applied to a surface would lack the ability to protect itself and the substrate from attack by fungi, algae and lichens. Latex emulsions and aqueous bases used to manufacture latex paints provide the ideal breeding ground for microbial growth. Without microbial control products, paint would completely break down during storage and would lose all viscosity, texture and adhesion ability.

Thanks to modern antimicrobial technology paint can now last several years and the finished coatings will last much longer, greatly extending the lifecycle of valuable assets. In turn, this extends the time and need to harvest new natural resources thereby reducing the environmental footprint under a more sustainable approach from ‘water-based’ products. Finally, for any leftover architectural paint products in Canada the manufactures assume full responsibility for paint recycling under provincial legislation, completing the circle in a circular economy approach to paint waste recovery. Biocides continue to play a critical role in Canada’s sustainability.

With the obvious benefits of biocides in paint and coatings it is becoming increasingly concerning to industry, and ultimately consumers, as to why regulatory authorities are evaluating them harshly and differently from one country to the next. For Canada this means a growing lack of alignment with our largest trading partner, the United States. Non-alignment will lead to more outright bans or restrictions in Canada that render such ingredients unusable or ineffective in protecting ‘water-based’ paint. Ultimately, this could also render the paint products useless for those who rely on their performance to extend the lifecycle of their assets, which help them to also reduce ‘their’ environmental footprint.This is not to suggest that these biocides should not be reviewed and controlled, but that the risk assessment methodology and approval process must be more evidenced-based and must be completed based on consistency with other peer reviewed and expert scientific risk assessments. 

Having critical biocides for paint and coatings put through a rigorous evaluation process and approved for use in one country, while in another country restricted for the same use levels or banned outright, based on the same data, raises serious questions. This is especially troublesome when a company can use a product in the United States for paint preservation, but not in Canada, where paint applications are similar. And, when that same company has to either reformulate the product for Canada, or take it off the market altogether in Canada, it negatively impacts all in the value chain.

Persistent challenges in the evaluation of critical biocides for coatings in Canada are simply not good for the country. Find out more about CPCA’s advocacy on this important issue for the coatings industry via the Canada CoatingsHUB.