ILOILO CITY, Philippines—Groups opposing the use of genetically modified organisms (GMOs) are calling for the compulsory labeling of products containing GMOs as a guide to consumers.

Lawyer Lilibeth Aruelo of The Third World Network Forum, an international network on environmental and developmental issue, said the manufacturers of products containing GMOs should be required to indicate its contents in the product label.

"Consumers in the Philippines do not know if the products they are buying contain GMOs and they should be provided with this information so they can choose," Aruelo said in a forum on genetic engineering held in Iloilo City Wednesday.

A GMO is a plant, animal or microorganism with its genetic code changed through biotechnology in order to give it characteristics that it does not naturally have.

GMOs have been used in agriculture, including the production of pest resistant and large-yielding crops and in medicine.

While its proponents see GMO production as a leap in technology and production, various sectors have opposed it because of its impact on environment and health.

Aruelo called on legislators to amend the Consumers Act (Republic Act 7394) so it would include the mandatory labeling of products containing GMOs.

She said such measures were necessary in the absence of a law in the country regulating the production and the use of GMOs.

The only regulation is contained in the Department of Agriculture Order No. 8 issued in 2002, which regulates the importation of GMO products.

Camilo Beltran, a Mexican scientist and research associate at the New Zealand-based Center for Integrated Research in Biosafety, pointed out, during the forum, the urgent need to raise public awareness of the impact of GMOs on the environment, health, agriculture and food security.

Beltran said the Philippines was one of the 12 countries that have adopted or allowed entry of GMO products, including corn, potato, canola, sugar beet, soybean, cotton and alfalfa.

"We have been using GMO products for 15 years but we have had few researches and studies on its effects," Beltran said. He said there was no research on the safety of GMO products in the Philippine setting.

Beltran said concerns have been raised after recent research findings showed that some GMO products, which were developed to kill harmful organisms, have toxic effects on non-target organisms, including those that play an important role in biodiversity.

He said several countries like France, which initially allowed the importation of GMO-containing products, have stopped importing them after new findings raised safety concerns.

Aruelo urged local government units to pass ordinances barring the entry of products with GMOs in their area, similar to the ordinance passed by the Negros Occidental provincial board in 2007, which barred the entry, planting, transport and selling of GMOs in the province.

The ordinance was used as the basis in rejecting shipments of GMO corn in Bacolod City this month.