Sep 09, 2011

Research Finds Plastic Bottles Could Clean Arsenic-Contaminated Water

Monmouth University chemists finds chemical on plastic able to bind to arsenic

Chopped up plastic bottles covered in a common chemical may be a simple and inexpensive method for removing arsenic from drinking water.

A team of chemists at Monmouth University found that bits of plastic coated with cysteine, a common molecule found in foods, bind to arsenic.

“Laboratory experiments have shown that the method has the potential to be very efficient and very cost effective,” Tsanangurayi Tongesayi, lead author of the study and an assistant professor at the university told SciDev.Net.

“The method uses plastics which are cheap and locally available,” he said. “[It] is eco-friendly because it involves recycling of plastic bottles [and] is also safe because the chemical ingredients used are not toxic.”

Tongesayi presented his team's findings last week at the annual meeting of the American Chemical Society on Aug. 31. The researchers showed that the method could reduce arsenic content from 20 ppb—two times higher than the safe standard set by the Environmental Protection Agency for drinking water—to 0.2 ppb.

Tongesayi said they were now looking for a commercial partner to scale up the process. In Bangladesh alone some 35 million people are exposed to arsenic contamination from drinking water, according to the Department of Public Health Engineering (DPHE).

But Guy Howard, the U.K. Department for International Development's Research and Evidence Representative in South Asia, said first the technology had to show that it could work in field conditions, which may vary and where “other chemical species compete with arsenic for adsorption sites.”

“Finally such a technology has to pass regulatory requirements ... Bangladesh has a very stringent technology verification process and technologies are only accepted for wide deployment once this is passed,” he said.

Shudhir Kumar Ghosh an engineer at the DPHE said the new method has good prospect in Bangladesh since it will use low cost plastic bottle and the easily available chemical.