The Environmental Protection Agency has concluded that a law is needed to protect the public against abuses or dangers created by science's ability to make news forms of life in the laboratory, an EPA official said yesterday.

Del Barth, EPA deputy assistant administrator for health and ecological effects, said EPA will recommend that President Carter back a federal regulatory bill now being prepared by an interagency committee.

The bill would in effect allow the government to license scientists or their institutions or employers to combine the genes of different organisms for study or for practical uses such as trying to make new medicines or other products.

Both Barth, EPA representative on the interagency committee and Rep. Paul G. Rogers (D-Fla.), House Health subcommittee chairman, reported that the interagency group has reached a consensus in favor of new legislation.

Rogers said he will not wait for the committee but will introduce his own, possibly stronger bill in the House today to seek to put all scientists and companies doing the new research under federal scrutiny and control. He also announced March 15, 16 and 17 hearings before his subcommittee.

There is already a bill before Congress to control what the scientists call "the new genetics." It was introduced by Sen. Dale Bumpers (D-Ark.), Sen. Pete V. Domenici (R-N.M.) and Rep. Richard L. Ottinger (D-N.Y.).

Hearings are also planned by the Senate Health subcommittee headed by Sen. Edward M. Kennedy (D-Mass.), and Kennedy also is expected to introduce legislation for genetic research controls.

In the past two days the new research has been called both "wise and prudent" and "unwise and dangerous" by contending scientists and others at a National Academy of Sciences public forum.

In an estimated 300 projects at universities, federal research centers and nine corporations, scientists are inserting the genetic material, or DNA - deoxyribonucleic acid - from mammals, frogs, yeasts and microbes into host colonies of bacteria to make life forms that do not exist in nature.

Dr. Francisco Jose Ayala of the University of California at Davis told the forum he is a member of the new ad hoc EPA committee to try to identify any environmental dangers that might be caused by the new research should it go wrong.

He said there is EPA concern that the supposedly harmless E. coli, the bacteria being used by the genetic experimenters as hosts for the new recombined genes, might turn into strains of E. coli like those that commonly cause human diarrhea and dysentery and urinary infection.

The National Institutes of Health has issued strict guidelines to try to prevent any mishaps in federally subsidized laboratories. But EPA feels the potential risks require wider controls, Barth reported.

Some scientists and groups - including the new Coalition for Responsible Genetic Research - have urged a more drastic step: an international moratorium on all such research. A labor spokesman at the forum - Anthony Mazzocchi, director of the Citizenship-Legislative Department of the Oil, Chemical Atomic and Workers union - called for a halt "until we have resolved all the outstanding questions."