South Africa is in the "bizarre" position of having liability provisions in law that mean users - not producers - will be liable for any consequences of consuming genetically modified organisms (GMOs).
"A provision like that looks like the fingerprint" of industry and multinational companies, an attorney specialising in environmental law, Cormac Cullinan, said on Wednesday.
He was a member of a delegation who spoke to members of the portfolio committee on science and technology on the safety and regulation of GMOs.
Cullinan said he had not encountered a provision like South Africa's in any other law and he believed it was not in the country's interests.
He appealed for more transparency and a fundamental "re-look" at the regulatory framework of GMOs in the country, which companies were using as "a giant laboratory".
The regulations made it difficult, "if not impossible", for civil society to participate in decision-making.
"I don't believe the regulatory system complies and conforms with the constitution."
Decisions were taken behind closed doors, with available risk assessments of GMOs based on information gathered outside the country and on species not even found in South Africa.
"Information is skewed in favour of large companies," Cullinan said, adding that scientists here remained silent for fear of losing research grants.
Earlier, Glenn Ashton of environmental lobbyist group SAFeAGE, said South Africa stood almost alone in its failure to adhere to the African Model Law on Biological Resources. The GMO Act and its amendments "completely failed" to maintain the most minimal standards of the African Model Law or the United Nations-sponsored Cartagena biosafety protocol.
"We, with the rest of Africa, are calling for the regulation of these technologies to be enacted in a transparent, meaningful, inclusive manner that upholds mutually agreed scientific, ethical, legal and moral standards."
The regulation of science had to be in the public interest and could not be slanted towards vested interests, Ashton said. He implored MPs to ensure there was a meaningful biosafety regime.
Bishop Geoff Davies of the South African Council of Churches said the patenting of life by corporations was "immoral". It was clear the consequences of genetic tampering were unknown.
"If we are going to play God, let us know what is going to happen."
It verged on the criminal that GMO food didn't have to be labelled. "Without being told, South Africans became the first people in the world to eat genetically engineered white maize. The public has a right to know what we are buying and eating."