Canada: MDIs in DIY Products Are Risk to Respiratory Health

Canada has confirmed a preliminary conclusion that five methylenediphenyl diisocyanates (MDIs) found in consumer products represent an unacceptable risk to human health.

The substances are used primarily in the production of polyurethane products, such as adhesives, coatings, insulation foams, flexible packaging laminates and foam slabs for furniture. They are also used as adhesives in the production of engineered wood products, such as oriented strand board.

But there is evidence that they cause cancer, as well as sensitising the respiratory tract and skin.

In its final screening assessment, the Canadian government concluded that the five substances meets the human health criterion set out in section 64 of the Canadian Environmental Protection Act, 1999 (Cepa, 1999). The assessment focused on the risk of acute respiratory toxicity, associated with exposure to certain polyurethane foam (SPF) spray products for DIY activities. The products were based on a two-component system and a low-pressure spray mechanism.

The government's conclusion will result in the substances being recommended for addition to the list of toxic substances in Schedule 1 of the Act, which triggers regulatory measures to manage the risk.

The proposed risk management action currently under consideration is to work with experts, manufacturers and trade groups – such as the American Chemistry Council's (ACC) Center for the Polyurethanes Industry (CPI), the Canadian Plastics Industry Association (CPIA) and the Retail Council of Canada (RCC) – to develop a code of practice under section 55 of Cepa.

This would be used to create standardised information and recommendations regarding the products, to inform DIY users about proper personal protective equipment (PPE) and other conditions needed for the safe use of low-pressure two-component SPF consumer products.

The five MDIs are: 4,4′-MDI; 2,2′-MDI; 2,4′-MDI; mixed MDI; and pMDI.

MDAs
In the same assessment, the Canadian government concluded that two methylenediphenyl diamines (MDAs) – 4,4'-MDA and pMDA – did not meet section 64 criteria. The substances are primarily used in manufacture of MDIs.

But the government has proposed adding significant new activity (Snac) provisions to them. These would designate as significant new activities:

the manufacture of consumer products or cosmetics with concentrations of the substances exceeding 0.1% by weight;
other activities related to consumer products or cosmetics, where the concentration of either substance in the product is 0.1% by weight or more and the total quantity of the substance in the product is greater than 10kg; and
uses involving more than 1,000,000kg of either substance, or those involving quantities of 100,000kg or more if fewer than three enumerated pollution control measures are implemented.
If adopted, these provisions would require any person engaging in a named activity to submit a significant new activity notification (Snan) at least 90 days prior to the import, manufacture or use.

The government has initiated a 60-day public consultation period for the proposal. Interested parties have until 9 August to submit comments.

The conclusions were made in a final screening assessment. They confirmed preliminary conclusions made in 2014.