ORGANIC food industry groups are demanding that ABC News fire correspondent John Stossel – and are threatening to sue.

They claim Stossel’s report on “20/20″ about organic vegetables was unsubstantiated by tests when he said organics are more likely to contain deadly strains of E. coli bacteria than food raised with more traditional methods.

ABC is slated to air a lengthy correction on tonight’s edition of “20/20.”

Stossel was reprimanded by ABC for the report and his producer, David Fitzpatrick, was suspended without pay for a month.

But the groups say it is not enough.

If ABC does not fire Stossel, “than I will continue to make noise until he gets fired,” vowed Kenneth Cook, president of the Environmental Working Group.

“We also want a second retraction to air,” during an all-important sweeps month when viewer levels are at their highest, Cook said.

Stossel’s report, which aired in February and was repeated last month, has caused nationwide sales of organic food to flop, the trade organizations contend.

The industry groups told reporters they are considering a class-action lawsuit against the network.

The food organizations say that Stossel’s segment used flawed testing to report that dangerous levels of E. coli bacteria are more likely to be found on organic produce because they are grown in manure.

The brouhaha was initially sparked when Stossel reported that tests had shown there was no pesticide residue on either the organic or inorganic produce.

But the trade groups are now slamming the whole report.

ABC has already said that the pesticide statement was wrong – but it has not yet said whether it will correct its claim about the greater likelihood of finding dangerous E. coli in organically grown food.

Cook said that the newsmagazine used preliminary, “high-school” quality tests – the kind that routinely reveal the presence of thousands of non-lethal strains of E. coli.

Only a second, more expensive and thorough test could have revealed if deadly strains of E. coli were present in ABC’s sample, OTA executive director Katherine Dimatteo said.

“We have completed our review,” ABC News said yesterday. “No further comment will be made.”