Environmental Risks Not Immediately Apparent

Manufacturers often rush to launch new products, hoping to gain a competitive edge. Yet the environmental risks of a new material or technology are not always apparent until the product has been on sale for a period. This is a problem even in industries such as pharmaceuticals in which products must undergo extensive testing and regulatory review for both effectiveness and safety.

It is an even bigger risk in the construction products industry. New building products may require testing to demonstrate certain aspects of safety -- such as fire resistance -- in order to comply with building codes. Yet there are not industry-wide  protocols for testing the environmental impact of a product, nor regulations mandating prior approval before marketing.

A case in point is nano-sized particles of titanium dioxide. The material has impressive potential for reducing airborne pollutants and making concrete self-cleaning. A marketing director promoting the product once assured me the compound is inert, and saw no reason to delay the product's introduction until it could be tested for impact on ecosystems. When he boosted that he could eat a spoonful without ill effects, I responded, "Yes, but you are not a coral polyp."

Now, new research suggests my concern was not unwarranted:

According to a new Northeastern University study, titanium dioxide nanoparticles (nTiO2) can disrupt photosynthetic organisms vital to aquatic ecosystems. Long used in paints, coatings, cement, and tile to create bright white coloring, titanium dioxide is now used in nanoparticle form in cosmetics, sunscreens, food coloring, and even building products, particularly white concrete products that are claimed to clean the air.

April Gu, Carla Cherchi, and other environmental engineers studied how nTiO2 affects one blue-green algae organism that contributes to aquatic nitrogen and carbon cycles. The researchers found that algae growth was reduced by 90 percent and nitrogen fixation activity was diminished when the organisms were exposed to nTiO2 at levels similar to those found in wastewater. Effects increased with exposure time and nTiO2 concentrations. The laboratory study did not evaluate the effect of titanium nanoparticles in the environment, or whether such particles are released from common products. For more information visit www1.coe.neu.edu.
Elsewhere, I have suggested prudent measures that can be taken to use TiO2 in building products, even while further environmental safety research is being conducted. The point of this post is to urge all members of the construction industry to proceed with caution when investigating new materials that have not been rigorously tested for environmental safety.