SHIFTING to chemical-free fertilisers could triple farmers' rice yields and produce more profitable crops at a time when Cambodian rice exports are on the rise, say agriculture officials.

"Rice grown with natural fertilisers is easier to produce and more profitable than rice grown with chemical fertilisers," said Khem Chenda, director of administrative affairs at the Ministry of Agriculture.

"Cambodian rice is very popular on the world market," Khem Chenda said, adding that countries such as Germany, the United States, Saudi Arabia and Kuwait have purchased millions of tonnes of rice from the Kingdom this year.

Farmers using chemical fertilisers pay about US$35 to $70 per 50-kilogram bag, and their yields sell for about $250 per tonne on the international market, Khem Chenda said.

But they face numerous health problems from prolonged exposure to chemicals, ranging from skin irritations to lung cancer, he added.

Despite the risks, some farmers see no alternative to chemical fertilisers. "I know that using [them] is dangerous, but I cannot stop," said Soun Saray, 45, a farmer from Svay Rieng province, who said he was worried that without them insects would destroy his crops.

"Farmers shouldn't worry about organic fertiliser," said Chan Vannak, general manager of Bayon Heritage Holding Group. "They will increase the quality and quantity of paddy yields and for a cheaper price."

Organics cost $27 per 50kg bag and crops sell for $300 per tonne, Chan Vannak said.

Bayon Holding Group imports organics from Japan for resale in Cambodia, Chan Vannak said, adding that he has already sold about 500 tonnes.

The agriculture ministry recommendation follows a push by Prime Minister Hun Sen to capitalise on global inflation and rising demands for Cambodian rice exports.

Cambodia exported 2.5 million tonnes of rice last year, Hun Sen said earlier this month, and the new farming and irrigation methods could soon quadruple that number.