What was going on when I was born?

At least 60 people were killed and 700 injured when a huge bomb exploded in Teheran's main square, the Iranian state radio reported today. Most of the casualties occurred in nearby hotels, restaurants and passing buses, the radio said. It said the bomb consisted of about 330 pounds of TNT packed into a parked truck. No group claimed responsibility for the bombing, which ocurred Friday night. But the Teheran radio, monitored here, blamed it on ''American mercenaries.''

From Virginia to California, Democratic House candidates with serious hopes of ousting incumbent Republicans are making the 1982 election a referendum on the economy. Gene Eidenberg, director of the Democratic National Committee, said he was pleased to see that Democrats First of two articles. were sustaining an attack on the ''radical'' economic policies that Republicans had voted for. Rarely do candidates speak that sharply, but sometimes their tone is blunt, as when Frank Harrison tells voters in Scranton, Pa., that the policies of President Reagan and of Mr. Harrison's Republican opponent, Representative James L. Nelligan, amount to a deliberate choice to increase unemployment. Sometimes it is gentler, as when Norman Sisitsky's television commercials in southeastern Virginia proclaim, almost sorrowfully, ''The Republicans didn't mean to start a recession, but they did.''

China is causing widespread and serious damage to its natural environment in its effort to quadruple its economic output in the next 20 years, according to a survey of the published writings of more than a score of Chinese scientists. Vast forest areas have been denuded, lakes and streams have been polluted and substantial soil erosion and loss of arable land have occurred, the survey reports, as China has expanded and upgraded its farms, factories and utilities. The consensus among the scientists, writing in official scientific and political papers published in Chinese journals, is that the environmental deterioration poses a serious threat to their nation's physical well-being and hence to its social stability. The survey, to be published in the October issue of The Bulletin of the Atomic Scientists, was done by Dr. Vaclav Smil, professor of geography at the University of Manitoba in Winnipeg, Canada. It is believed to be the first comprehensive view of all aspects of the condition of China's natural resources.

WHITE PLAINS ONE of the things that happens when politicians march off to autumnal campaigns is that administrators, like warriors' wives, have to stay behind and do the chores. So it is for J. Robert Dolan, whose daily focus must continue to be such matters as the airport curfew, the proposed utility agency and the next county budget, while ''the boss,'' County Executive Alfred B. DelBello, spends three or four days a week running for statewide office. Mr. Dolan is the county's executive officer, the top appointive post in county government, to which Mr. DelBello named him the day after he took office as County Executive in January 1974. Both men come from Yonkers, where Mr. DelBello was Mayor and Mr. Dolan was assistant city manager. Mr. DelBello now lives in Waccabuc, and his 44-year-old executive officer moved to Mamaroneck three years ago, but they work closely from adjoining ninth-floor offices in the County Office Building here. Campaigning before the primary elections, Mr. DelBello was absent from his corner office an average of two days a week. Now that he has won the Democratic nomination for lieutenant governor, he expects his time away to increase as the Nov. 2 election appoaches, perhaps even to ''stay out a week or two'' at the end. This probability, however, does not imply that Mr. Dolan will take over more responsibility, according to Mr. DelBello, just that ''he has to give it more'' work.

The California Angels took the lead on Fred Lynn's two-run homer in the fifth inning today and held on to clinch the American League Western Division title by beating the Texas Rangers, 6-4. The title was the first for Gene Mauch in his 23 years of managing. Trailing by 4-3 at a time when second-place Kansas City had already beaten Oakland, 5-4, the Angels rallied in the fifth off Charlie Hough (16-13). Rod Carew opened with a walk, and Lynn hit his 21st home run on Hough's first pitch to him.

House and Senate members, heading home to concentrate on re-election campaigns, expressed resentment today that fiscal issues had preoccupied the last 20 months of this session of Congress at the expense of other legislation. Frustration over the focus on fiscal issues has led to general agreement on the need to change Congressional procedures, which some members of Congress say could lead to destruction of the Budget Act. Ted Stevens, Republican of Alaska, the Senate majority whip, said when asked to describe the 97th Congress, ''It's been an endless series of meetings seeking to reach some consensus on where we should go with our fiscal ship of state.'' 'Reform the Reformers' ''The frustration here is over the complexity of the fiscal management process, and the inability of members to raise other issues,'' the Senator continued. ''We've got to reform the reformers.''

-------------------------------------------------------------------- Laurence Shames is a freelance writer with a special interest in the arts. By LAURENCE SHAMES Mikhail Baryshnikov defected to the West in 1974. Soon thereafter, he became one of the leading stars of American ballet; by 1977, he was appearing in a major motion picture, ''The Turning Point,'' and in 1980 he was named artistic director of American Ballet Theater. Also in 1974, Alexander Solzhenitsyn was expelled from the Soviet Union. He lives now on a 50-acre Vermont estate, where he basks in adulation, royalties, and an unceasing flood of honorary doctorates from American universities.

''As a general thing I have not 'duped the world' nor attempted to do so ...I have generally given people the worth of their money twice told. The Mermaid, Woolly Horse, Ploughing Elephant were merely used by me in advertising to attract attention.'' - From ''The Selected Letters of P. T. Barnum, edited by Arthur H. Saxon, to be published by the Columbia University Press. HAS P. T Barnum, the famous 19th-century showman, circus owner and Bridgeport resident, been misunderstood all these years? Was he so imprisoned in the con-man legend of his own making that in the end it obliterated his real character, even into history? Arthur H. Saxon, a noted circus historian who lives near Fairfield Beach, believes so. He came to this conclusion after spending the last three years collecting more than 3,000 letters that Phineas Taylor Barnum had sent to friends and business associates.

Why he remains has something to do with hard work, of course, and it has something to do with waking up at night in a cold sweat after all his money was stolen by his best friend - who also happened to be his agent. Through 10 seasons, starting with the 1972-73 team that produced the worst record in the history of the National League, sticking with it to help capture the last three Stanley Cups, Nystrom's career has been erratic, but the style has varied little. And that is the reason why Bill Torrey, the club's prescient president and general manager, has kept him. The only other Islander remaining from the 1972 team is Billy Smith, the goalie. In the age of the 50-goal scorer, Nystrom - affectionately known as Bobby Nye - has gone four seasons without getting 30. Torrey describes him as ''a streaky player.'' But things just seem to happen when Nystrom is there.

Steve Lawson recently adapted Bernard Pomerance's play ''The Elephant Man'' for television. By STEVE LAWSON The set looks like a gigantic garbage dump, crammed with bicycles, cast-off Christmas ornaments, tires, toothpaste tubes, even parts of a wrecked ship, glowing in unearthly hues. The dump reaches out into the theater, circling completely around the mezzanine rail. Against this collage, strange forms skitter and crouch, clad in fur, satin and stripes, illuminated by shafts of moonlight and neon, piercing the air with snatches of songs and animal hissings. This is the world of the musical ''Cats,'' one of the most eagerly awaited theatrical extravaganzas of recent seasons, opening Thursday evening at the radically revamped Winter Garden. The artistic contributors include Andrew Lloyd Webber, the composer, whose past musicals include ''Evita'' and ''Jesus Christ Superstar,'' and T.S. Eliot, author of such poetic classics as ''The Waste Land'' and ''The Hollow Men,'' whose 1939 volume of verse, ''Old Possum's Book of Practical Cats,'' furnished both inspiration and lyrics for ''Cats.''

COMMERCIAL fisherman on Long Island have asked the Federal Government for fast action on a proposal that would ban some foreign fishing fleets within 100 miles of the United States coastline in the peak fishing season. A proposal now being considered by the National Marine Fisheries Service would ban foreign long-liners from the waters 100 miles from the North Atlantic coast in a zone extending northeast from Cape Lookout, N.C., to the Georges Banks just below the United States-Canadian border. The ban would be in effect from June 1 to Nov. 30, the peak season for fishing in the North Atlantic. David Crestin, director of the Fisheries Service, said the proposed ban was designed to reduce the number of incidents of damage to longliners' gear when their boats cross lines laid by other boats. He said the Federal Register indicates 52 such gear conflicts in the North Atlantic in 1980 and 1981.

DAVID GEFFEN'S phone rang all morning, the sound richocheting like c oins off the David Hockney paintings that hang serenely in his F ifth Avenue apartment. First, Sherry Lansing, the president of 20th C entury-Fox Productions, was on the phone. Then Steve Ross, the c hairman of Warner Communications. Mr. Geffen hung up. He knew he waso n a roll and smiled. The phone rang again. There was a hush, then the former whiz kid of the record industry, who directed the careers of many of the seminal rock groups of the 1970's, let out a cry. He had just clinched a movie deal with Steven Spielberg, the director of ''E.T.'' Holding the phone away from his ear, he started to dance, a crooked little Rumpelstiltskin hop. For one moment, Mr. Geffen, by virtue of his height and his elasticwaist trousers, looked more like a 12-year-old than a bi-coastal mogul of the entertainment industry. But he is not 12. He is 39. And, after a four-year retirement brought about when a tumor in his bladder was somehow misdiagnosed as cancerous, he has begun a second career with a drive bordering on vengeance. At a time when the fortunes of the entertainment industry are sagging, Mr. Geffen's $100 million show business company for now is soaring.