Canadian scientists develop pesticide-detecting 'dipstick'

(thieury)

Scientists from McMaster University in Hamilton, Ontario have developed a dipstick test that can detect minute amounts of toxins and pesticides in foodstuffs that is slated to be less costly than current pesticide testing methods and can produce results within minutes, the American Chemical Society (ACS) reports.

The 10 cm-long paper-based strip changes color shades depending on the amount of chemicals present. In laboratory studies using food and beverage samples intentionally contaminated with common pesticides, the strip accurately detected trace amounts of the chemicals within five minutes, according to the scientists.

The paper strip that reacts to a number of toxins could have many applications, primarily in the food industry and agricultural production, but it could also be used to test for chemical warfare agents, according to John Brennan, lead researcher of the project.

The dipstick can pick up the presence of harmful organophosphate pesticides that are banned in North America and in Europe but that continue to be used in agricultural crops in countries like India and China, Brennan said. It could also be adapted to test for toxins in water or even for E-coli before it enters the food chain, he said.

"The tests could be most useful in developing countries and in the market of imported fruits and vegetables as well as in rural settings for on-site testing where testing equipment is not available or there's no electricity," said Brennan in an interview.

He added that a number of regulatory hurdles and scale-up issues remain before the dipstick would be available. Each strip could cost as little as 25 cents, he said.

The report appears in the November 1 issue of ACS' Analytical Chemistry.