The American public will never know if food additives like the sugar-substitute NutraSweet pose a health threat to consumers because government tests neglect areas of potential danger, said an expert on technology policy from MIT last night.

Without calling NutraSweet a definite health threat, Steven Farber of MIT's Department of Brain and Cognitive Science and the Technology Policy Program said the current testing system which relies on chemical companies to police themselves is "inadequate."

"We are all part of a giant clinical experiment," said Farber, indicating that he didn't think anyone was keeping track of the results.

Farber's comments came before an audience of 30 in a speech sponsored by Eating Concerns Hotline and Outreach (ECHO), entitled "Are We the Dupes of the NutraSweet Company? The Politics and Chemistry of Artificial Sweetners".

He said that often the Food and Drug Administration allows the drug companies to take short cuts on their testing, because its standard of "reasonable certainty of no harm" is too vague.

"It has never been formalized what reasonablecertainty is," said Farber, who is in the processof receiving his Ph.D.

As an example, Farber said NutraSweet was nottested with the substances with which itfrequently occurs, like caffeine, despite the factthat the threat of drug interaction is commonlyknown.

NutraSweet was initially approved in themid-1970s by the FDA with a warning forphenylketoneurics, those whose bodies cannothandle the presence of phenylalanine, an aminoacid.

Soon after the approval questions began toarise about the validity of the G.D. SearleCompany's data and in 1977 the FDA asked a Chicagogrand jury to investigate the accusations. Anindependent organization was called in to questionthe accuracy of the reporting of the scientificfindings.

The independent investigation sided withSearle