Monsanto Co. hopes to use gene-splicing techniques to fashion microbes to kill insects that attack young corn plants. But the company's global marketing plans -- like similar plans of other companies -- are clouded by the uncertainties of how countries will regulate the newly emerging products of biotechnology.

Biotech companies worry that individual nations may impose widely varying data requirements, standards and tests that would increase development and marketing costs of insecticides, crops and drugs produced through new methods of genetic engineering.

Some companies and parties to the regulatory debate in this country also worry that inadequate international safety standards could lead to an accident that might harm people, the environment or public confidence in a new industry. They also note that living bacteria, tailored through gene splicing to act as a pesticide or insecticide, may migrate by wind or water across national borders and reproduce.

Now two members of Congress have charged that the Reagan administration may have endangered its chance to coordinate a consistent international approach.

Rep. John D. Dingell (D-Mich.) and Sen. David F. Durenberger (R-Minn.) said in a letter to the State Department dated Oct. 22 that the U.S government has taken "actions which imperil the success" of an Organization for Economic Cooperation and Development effort to draft guidelines on biotech regulation for use by its 24 member nations.

Citing "disarray" and an "absence of adequate leadership" within the U.S. delegation, the congressmen asked Secretary of State George P. Schultz to "get the U.S. participation in the OECD process back on track."

"We must have all nations regulating biotechnology if we are going to protect the public from potential hazards," wrote Dingell and Durenberger, who are chairmen of congressional subcommittees overseeing the development of biotech regulation in this country.

Reagan administration officials said that the process is on track and that they have worked to improve the draft guidelines in ways that will increase the chances for international consensus.

Food and Drug Commissioner Frank E. Young is leading a U.S. delegation that plans to present a new draft of the guidelines Monday at a meeting in Paris of an OECD working group representing all 24 members. Before leaving, he said, "I believe agreement will be reached on a good and useful document."

Young and the State Department said the congressmen's letter reflected a "misimpression" that there is conflict within the U.S. delegation.

"There is one U.S. government position," said a State Department official who asked that his name not be used. "We want to safeguard health and the environment, but we also don't want this new technology to be straitjacketed."

The OECD has been working since mid-1983 to develop a consensus on the scientific principles and issues to be considered in evaluating the new products of gene splicing. The OECD Ad-Hoc Expert Working Group on Biotechnology has been working to draft a document that would reflect the consensus and that different countries could use as they develop their individual regulations, codes or practices.

The U.S. government, pressed into action by the rapid progress of biotech companies in this country, has begun developing its own system for reviewing genetically engineered insecticides, pesticides, food additives, drugs, crops and chemicals.

But in many other countries, the regulatory hurdles are unclear or nonexistent. Most countries have established methods for evaluating the quality and safety hazards of new drugs, crops and chemicals, but it is not known if they will treat differently the products of new technologies such as gene-splicing and cell fusion. This uncertainty makes it difficult for Monsanto and other biotech companies to plan, or to be sure that their investments in the new technology will pay off in international markets.

"If biotech companies are going to commit over time to a risky technology, they need a reasonably predictable future for commercialization," said Will D. Carpenter, general manager for technology of Monsanto Agricultural Products Co. Biotech companies will face "uncertainty if there is no sound, effective regulatory environment . . . not only in this country, but internationally."

No products are being held up now, said Harvey Price, executive director of the Industrial Biotechnology Association. But "looking down the road, it is important to do what you can to prevent roadblocks."

Dingell and Durenburger expressed concern because the United States caused a four-month delay in the OECD schedule and has rewritten major parts of the OECD document draft produced at a meeting of the 24-nation working group in Paris last May.

A draft entitled "Safety and Regulations in Biotechnology" was prepared at the May meeting, was scheduled for final revisions by a smaller group in August and was expected to be ratified by all 24 countries in October. "In reliance on this plan, a number of countries had committed their governments to decision-making deadlines on regulatory policies," Dingell and Durenberger wrote in the letter, which was reported Nov. 10 in Genetic Engineering Letter, an industry publication.

But at the May meeting, "the U.S. delegation of experts appeared to be in disarray," the congressmen wrote. "Internal leadership was lacking, and some delegates from other countries asked if the U.S. had been attempting to disrupt the process."

A June 4 cable to the State Department from two members of the U.S. delegation said that "agreement in principle was achieved on the document" and that a drafting group would meet in August to complete the final revisions. But Young, now the leader of the delegation, said recently that no U.S. representative to the meeting had authority to approve the May draft. "The U.S. did not agree to it," he said.

Young said that "there were some real problems with it," that major revisions were necessary and that the U.S. delegation postponed the August meeting so it could improve the document. "We feel a substantial improvement has been made," he said.

The State Department official said there were two major problems with the May draft: The tone was "unduly alarmist" and "overly regulatory." The document exaggerated the potential risks of genetic engineering because it "did not reflect up-to-date science," he said. It also provided information that was too specific for a developing technology and that might be taken as prescribed rules rather than general guidelines, he added.

Young said the May draft "was too specific, and therefore too dated" for a rapidly moving science, and that "there was more of an emphasis on risks in industrial scale-up than is currently perceived."

But the European Federation of Biotechnology, an association of more than 50 scientific member societies, wrote Nov. 5 that it considered the May version "acceptable" and that its working party on safety "will continue its work without awaiting the outcome of the OECD negotiations." The group "was counting on a positive outcome from the OECD effort in summer 1985."

Japan's Ministry of International Trade and Industry, which is preparing its own biotech regulatory plan, wrote to the OECD that "we basically agree" with the May draft. The Japanese expressed "disappointment" with the cancellation of the August meeting and conveyed "hope that the United States will go through the accepted formalities in the future so that this kind of unilateral cancellation will not occur again."

The new draft of the document, which Young will present to the Paris meeting, has won praise from some members of the U.S. biotech industry. The IBA wrote in October that its "earlier reservations have been allayed" by the new version. Monsanto termed the new draft "clearly written, concise and to the point," adding that "the strong upfront discussion of the benefits of biotechnology set an excellent tone for the remainder of the report."

The two drafts also reflect the current debate within this country over the riskiness of biotechnology. The Reagan administration has stated that existing laws and agencies can handle products of genetic engineering, without the need for new regulation. The Food and Drug Administration already has approved two human drugs produced through gene splicing, and the Environmental Protection Agency has approved the first outdoor release of a gene-spliced living organism.

Environmentalists argue that the administration is moving too fast, playing down the risks and proceeding without the scientific ability to judge them.

Dingell and Durenberger also expressed "concern that the reputation of the U.S. as a full, fair and reliable partner in OECD proceedings, which already is damaged by the developments of the past few months, not suffer further due to additional delay and reversals of policy."

Young said before leaving for Paris that he believes the OECD process is moving well and that it will yield "a document that fully reflects the appropriate scientific position at this time."