Nanoscale particles designed to block UV light

Over time the sun's ultraviolet light can cause cracking, fading and other types of solar degradation to plastics.

Ultraviolet light (UV) can also reduce the quality and shelf life of beverages and foods in transparent or semi-transparent packaging.

Finding better ways to block UV rays from passing through food and beverage packaging, while still allowing consumers to see the product inside, is a major goal within the industry.

This week DuPont announced the release of its Light Stabilizer 210, a plastic additive designed using extremely small particles of titanium dioxide, which have been nanoengineered to absorb UV.

While DuPont lists current potential applications for Light Stabilizer 210 as sporting goods, outdoor furniture, fabrics and carpet fibers and packaged products, the company has also applied in the US for regulatory approval for use in the food sector.

DuPont wants approval for use of Light Stabilizer 210 as a plastic packaging additive in 'indirect' food contact applications, said company spokesman Rick Straitman.

DuPont hopes to get approval in a few months for the product, he said.

In testing, Light Stabilizer 210 blocked twice as much UV light as several classes of competitive products, the company claimed in a statement.

Light Stabilizer 210 works by absorbing UV rays and changing them into small amounts of heat which dissipate quickly without damaging the structure of plastic, DuPont stated.

"The key performance advantage of the new light stabiliser is that its extremely small particle size provides much more surface area for UV absorption," the company stated.

As a siseable percentage of titanium dioxide particles in the product are nanoscale, DuPont has selected the additive as a demonstration case for application of a risk assessment process.

The Nano Risk Framework was introduced by DuPont and Environmental Defense introduced in June, a bid to meet scientific and consumer concerns about the technology.

The framework is a systematic and disciplined process to evaluate and address the potential risks of nanoscale materials.

Light Stabilizer 210 will be available for sale in November, the company stated.

DuPont claims to be the world's largest manufacturer of titanium dioxide, a material widely used as a pigment in the coatings, plastics and paper industries.

Light Stabilizer 210 is the first in a family of products based on the company's titanium dioxide process technology, said Richard Olson, vice president and general manager of the DuPont developing the technology.

"Our titanium dioxide manufacturing technology has transformed several times in the more than 70 years since it entered the DuPont product family," he stated.

"It's extremely gratifying to see this material transform yet again into a high performance product made using DuPont nanoscale science."

In other news, DuPont said in a separate statement earlier this month that the US Department of Justice had informed the company it would not be laying criminal charges against the company in relation to its studies on perfluorooctanoic acid (PFOA).

PFOA is used in the making of fluorochemicals, which are used in non-stick and oil and grease resistant food packaging linings.

Pizza boxes and confectionary wrapping are examples.

However the chemcials are known to rub off and migrate into foods.

Once ingested, the chemicals can break down into PFOA, a related chemical used in the making of Teflon-coated cookware.

While scientific studies indicate that PFOA poses little risk to human health, the Environmental Protection Agency (EPA) has been under pressure from community groups to ban the use of the chemical.

The situation came to a head in late 2005 when DuPont was hit by allegations that it hid studies allegedly showing the high health risks posed by the chemical.

DuPont denied the charges.

A subsequent statement by the Food and Drug Administration also backed up DuPont.

After the allegations the EPA called on DuPont and six other corporations to voluntarily eliminate PFOA and similar substances from plant emissions and products by 2015.

The companies were asked to meet the commitments in the US as well as at their operations overseas.

In January last year DuPont announced it would reduce its use of the chemical.

Earlier this year the company announced it had made "significant progress" in developing new high-performance products with reduced PFOA, adding that it would be able to phase out the chemical completely by the voluntary deadline.

According to Stacey Mobley, DuPont senior vice president and general counsel the justice department's decision supports the company's position that it acted responsibly in the matter.

"DuPont(TM)

Light Stabilizer 210 is the first product to use the Nano Risk Framework during the development process," said Gary K. Whiting, global venture manager for the new product.

"Because a portion of the product is less than the threshold 100 nanometers in size, we decided to examine it fully, strictly adhering to the Framework.

The Nano Risk Framework is an additional tool that allowed us to critically examine and thoroughly understand our product."