Geiger counters are probably ineffective for consumers in detecting hazardous levels of radiation in food and water at home, scientists, professors and device makers said.

Large samples should be tested in laboratory-like settings to obtain results, said Joseph Rotunda, who heads the radiation measurement division at toolmaker Thermo Fisher Scientific Inc. Determining whether food, water or milk is safe also requires expert knowledge and more sophisticated equipment than the typical devices sold online, said Atsushi Katayama, a member of the Japan Society for Analytical Chemistry.

“Just pointing a measuring device at your food before dinner is pretty much meaningless,” said Katayama, who has a doctorate in analytical chemistry from Hokkaido University. “Tap water and fish, for example, require special handling, isolation and concentration to get meaningful readings.”

Geiger counters offered as far away as Germany have sold out after the natural disaster that crippled Japan last month led to the world’s worst nuclear crisis since Chernobyl. Tokyo Electric Power Co. said yesterday its Fukushima Dai-Ichi plant, which has withstood hundreds of aftershocks since the March 11 magnitude-9 earthquake, may spew more radiation than the 1986 incident before the crisis is contained.

CONTINUED AT: http://www.bloomberg.com/news/2011-04-12/geiger-counters-to-find-radiation-in-meals-may-be-meaningless-.html