UN starts with Mediterranean in drive to clean up world's seas

Attempts are being made to set up global agreements to combat pollution of the seas of the world, which are threatened by tons of industrial waste, domestic sewage, and agricultural runoff.

The organization spearheading the effort is the United Nations Environment Program (UNEP), which has set ocean cleanup as one of its chief campaigns for 1984.

A breakthrough has already been made in the Mediterranean, one of the most polluted of seas. In August, the Athens protocol for the protection of the Mediterranean from pollution from land-based sources came into force.

The convention has been ratified by the parliaments of Algeria, Egypt, France , Monaco, Tunisia, and Turkey. This was the minimum level of approval needed to bring the convention into force, but the other states are expected to ratify the convention soon, bringing the entire Mediterranean under pollution control.

If fully carried forward, 16 countries will spend about $1.5 billion by the end of the century to clean up the Mediterranean.

Dr. Mustapha Tolba, executive director of UNEP, says the beaches of the Mediterranean were probably the most polluted by oil and its derivatives of all the seas. ''Swimming has become a risky venture in many previously safe recreational areas,'' he says.

In July, Colombia, Ecuador, Panama, and Peru took the first steps toward protecting their coastlines from land-based pollution and agreed to closely monitor marine pollution, especially oil pollution.

Some of the UNEP's pollution campaign is being charted in Geneva by an ad hoc working group of experts on marine protection. Governments, other UN agencies, and regional marine organizations have sent experts to the meeting, which is scheduled to end tomorrow.

East Africa may be the next coastal region to draft measures on marine protection. Kenya, Tanzania, the Seychelles, Somalia, Uganda, Madagascar, Mozambique, and Mauritius are expected to meet in December to discuss this.

Experts agree that discharges of waste from the land are the most significant sources of marine pollution. These discharges directly affect coastal waters, where more than 90 percent of fishery areas are located and where man's closest contact with the sea through bathing and fishing occurs.

Pollution comes from factories, plants, and discharge of human wastes into the water. The rivers of landlocked countries become polluted when they carry such wastes toward the sea.

International lawyers working on conventions and protocols say it is a formidable task to get agreement from countries with different interests. But one lawyer notes, ''It is a task that has to be done if the seas which provide life and a living for millions of people are to be saved from permanent pollution.''

A ''black list'' of substances that Mediterranean experts hope to ban from reaching ocean waters includes mercury, cadmium, used lubricating oils, phosphorus, carcinogenic or mutagenic substances, and radioactive substances, as well as some synthetic materials.

A ''gray list'' of certain less toxic substances can be discharged in a controlled manner - but only with a permit. These include zinc, copper, lead, titanium, arsenic, silver, cobalt, tin, crude oils, hydrocarbons, pathogenic microorganisms, and nonbiodegradable detergents.