Arsenic level less than 10 microgram per litre (ug/L) can be measured by using the method while those now used being in the country can not detect the contamination if it is below 50 microgram per litre.

The World Health Organization (WHO) - prescribed tolerable limit of arsenic in water for humans is 10 microgram per litre.

Thousands of people are being affected in the country with the deadly poison as they are unknowingly taking water with arsenic contamination of around 50 microgram per litre.

The new method is more accurate and precise and does not need use of atomic absorption spectrometer or other expensive equipment, according to the innovators.

In the 'arsenomolybdate' method arsenic can be detected by using a simple spectrophotometer, distillation unit for purifying water, analytical balance, top-loading balance, glassware, an arsine generator, scrubber and absorber and some very common reagents. All these cost Tk 6500 only while the methods now being used cost around Tk 37,000, Dr. Bibudhendra Sarkar, leader of team of foreign scientists, told this correspondent recently.

Any household or a small community can set up a small laboratory, which will open a new dimension in supply of arsenic-free water, he said.

The innovation has been made after eight year's experiment in four Kushtia villages by volunteer scientists called Scientists Without Borders, headed by Dr Bibudhendra Sarkar of the Hospital for Sick Children and Faculty of Medicine, University of Toronto, Canada.

The team included Dr Seth Frisbe, an environmental chemist, Dr Ericka Michel, a sociologist from Better Life Laboratories in Vermont, USA, Dr Donald Manyard of Johnson Company, Vermont, USA; Dr, Saul Sanchez, of Green Mountain Laboratories, Vermont USA; Dr Richard Ortega of University of Bordeaus, Franch and Ahmad Zaki Yusuf and Mohammad Yusuf Siddique of BANI, Kushtia.

They worked by rotation in Bualda, Fulbari, Komlapur and Jamjami villages.

Recently, Dr Mustanzid of the Department of Surgery, Faridpur Medical College and Dr Fatema Ashraf, Department of Obstetrics and Gynaecology, Rajshahi Medical College, joined the team.

Talking to this correspondent, Dr Mustanzid said they are now helping some individuals and small companies providing healthcare service in Kushtia to install small laboratories in the town. Gradually this will be expanded throughout the country.

Kushtia is one of the districts where the groundwater is highly contaminated with arsenic.

At least 63 per cent of the people in the district are facing the danger, according to a survey made by a foreign NGO in 2002.