HOW do you tell an immigrant simply looking for a job from a political refugee facing persecution back home?In a Europe where jobs were plentiful, where populations were tolerant of newcomers, and where laborers were needed, the difference hardly mattered. Both were accepted. But with Europe in a deep slump, the doubling in the number of asylum seekers in the last five years has suddenly become a vital policy issue. Most European governments clamped down on the numbers of immigrants coming for work. As the squeeze on legal immigration has taken place, however, an explosion of asylum seekers has followed. The reasons are partly political: The end of the cold war and the aftershocks it has sent throughout the third world have shaken the old world order. Many migration experts say the world's increasingly mobile poor are, by claiming refugee status, simply going through the only door to the West's wealth left open to them. In recent years, and particularly since the opening of Eastern Europe's borders, the number of asylum requests in Europe has jumped from 168,000 in 1985 to more than 400,000 last year. Germany alone accounted for half the total. In France, the number nearly tripled from 21,000 in 1984 to 62,000 in 1989, before falling slightly to 56,000 last year. In Austria, traditionally a transit country for refugees seeking to settle in other Western countries, immigration figures have shot up as other countries closed their doors - or experienced economic difficulties that made them less attractive to refugees. (See story at left.) ROM the 10,000 to 20,000 refugees or other immigrants who typically stayed on annually in Austria in the early 1980s, the number jumped to 65,000 in 1989, then nearly doubled to 120,000 last year. Perhaps the most unfortunate aspect of the rush for refugee status is that it has made the plight of genuine political refugees more difficult. Countries that generally approved one-fourth or more of asylum requests now typically approve less than 5 percent, with the assumption growing that all but a few are in fact economic refugees. The steady rise in asylum requests has also led to a backlog of cases so severe that some candidates wait four or more years before their request is denied. Specialists on immigration policy say the only way to safeguard the refugee concept will be to separate it from economic immigration. "One quite negative consequence of the tangling up [of immigration and political asylum] is that protection for genuine refugees is suffering," says Candido Cunha, of the Council of Europe. A workable refugee policy, he says, requires quick deliberation on a case, swift repatriation if asylum is denied, and separate immigration procedures so foreigners know there is a difference. "The key is governments acknowledging that immigration is going to take place, and dealing with that, too," he adds. Mr. Cunha and other experts say the situation requires a new definition of "refugee" that goes beyond a traditional application of the Geneva Convention on asylum, which demands proof of individual persecution. Some Scandinavian countries, for example, recognize a second category of refugees, applicable to people who cannot prove individual persecution yet who remain of "humanitarian concern." "There are people who have not been individually persecuted, but who nevertheless would be in danger if they returned to their country," says Karin Konig, a director of Vienna's Committee to Support Politically Persecuted Foreigners. "It's a matter of interpretation," she says. "But it seems hopeless that governments might start interpreting 'refugee' to include groups like civil war victims or Iranian women."