An 18-month congressional moratorium on banning saccharin ends today, but saccharin won't disappear yet from foods or drinks.

It won't disappear today, and it will probably still be there well into 1981, at the very least, though most scientists agree that the chemical sweetner can cause animal cancers and most likely some human bladder cancers.

As the end of the moratorium on saccharin action approached yesterday:

Food and Drug Administration Commissioner Donald Kennedy announced that his agency will wait for "some indication" of what Congress intends to do next before proposing any new restrictions.

Two key House members - Argiculture Chairman Thomas S. Foley (D-Wash.) and Commerce health subcommittee Chairman Henry Waxman (D-Calif.) - proposed bills calling for a new maratorium of FDA action, pending a look by Congress at the broad issue of food safety.

Waxman seeks a three-year moratorium, and there are other bills by Decomcrats and Rupublicans, liberals and conservatives, along similar lines.

Dr. Kennedy also siad that "if" the FDA, after reviewing the latest studies, proposes new restrictions - probably next fall - they could not take effect for at least 15 more months and perhaps longer.

All but Ottinger will support a new moratorium. He will seek only a three-year delay in FDA restriction - in effect, a phaseout of sacchairn - unless the FDA uncovers some new antisaccharin evidence sooner, or industry produces a safe substitute a sweetener.

But Ottinger's view does not seem to be the dominant congressional one, which is that the evidence against saccharin in weak - and millions of constituents depend on it to help them stay on reducing or diabetic diets.

Current food laws require the FDA to take some new action against saccharin, Kennedy plans to tell the Waxman subcommittee today. But he will come down hardest on its use by children, who may drink several diet drinks daily for years, and pregnant women, who can affect their babies.

Most scientists have agreed that, though saccharin is a relatively weak carcinogen, or cancer-causer, compared with some others, it also is a cancer promoter. This means it may act in concert with other carcinogens.

And no one knows yet how many saccharin-induced or "promoted" bladder cancers may appear in another decade or two, since heavy use of saccharin drinks began only in the 1960s.

Two medical groups will take conflicting positions today. The American Diabetes Association will back continued sale of saccharin and saccharin products for the present, though it encourages pregnant women and parent to "discuss" saccharin use with their doctors.

The American Dental Association will back saccharin use to sweeten toothpaste and other dental products "to ensure their proper use," but will oppose the far more massive use of saccharin in foods or as a table-top sweetener.

Though the congressional moratorium will end today, one of its provisions will remain in effect, said the FDA. This is the current warning on saccharin-containing foods and drinks: "Use of this product may be hazardous to your health . . ."