Nano products exposure may damage liver, skin

“Especially if the nanoparticles are indestructible and accumulate and are not metabolised, if you accumulate them in the organs, the organs could fail.”

Some doctors, scientists and consumer advocates are concerned that many industries are adopting nanotechnology ahead of studies that would establish whether regular ingestion, inhalation or dermal penetration of these particles constitute a health or environmental hazard, the paper said, adding that personal care products are simply the lowest hanging fruit.

But people are already exposed to nanoparticles. Stoves and toaster ovens emit ultra-fine particles of 2 to 30 nanometres, the paper said, citing the National Institute of Standards and Technology.

The researchers reported last month that long-term contact with such appliances could constitute a large exposure to the smallest of nanoparticles.

Several products already use nano-engineered materials, the Times said, adding that there are “nano pants,” stain-resistant chinos and jeans whose fabric contain nano-sized whiskers that repel oil and dirt, and nanocycles made from carbon nanotubes that are stronger and lighter than standard steel bicycles.

In lotions and creams, the use of nanocomponents may create a more cosmetically elegant effect like uniformity or spreadability, it adds.

Some ingredients, it said, may behave differently as nanoparticles than they do in larger forms. Nano-sized silver, for example, can act as an antibacterial agent on the skin.

Larger particles of zinc oxide and titanium dioxide result in white pasty sunscreens; but as nanoparticles, they appear more transparent.

When it comes to beauty products, the report says, some consumer advocates are concerned that dynamic nanoparticles could pose risks to the skin or, if they penetrate the skin, to other parts of the body. Mineral sunscreens have attracted the most attention.

“Substances that are perfectly benign could be toxic at the nano scale,” Michael Hansen, a senior scientist at Consumer Union, the company behind Consumer Reports, was quoted as saying. “Because they are so small, they could go places in the body that could not be done before.”

The magazine published a study it had commissioned that found mineral nanoparticles in five sunscreens, even though four of the companies had denied using them.

In October, the paper said, Hansen sent a letter to the Food and Drug Administration commissioner, asking the agency to require cosmetics and sunscreen manufacturers to run safety tests on nano scale ingredients.

In the letter, he cited a few studies published in scientific journals that reported that exposure to nanoparticles of titanium dioxide caused damage to the organs of laboratory animals and human cell cultures.

But cosmetics industry representatives told the paper that there was no evidence that personal care products that contain nano-size components constitute a health hazard. Furthermore, no rigorous clinical trials have been published showing that cosmetics with nanocomponents caused health problems.