Polybromated biphenyl may soon make the lexicon of American household words - at least in its shorter form, PBB. Through human error and bureaucratic clumsiness, this poisonous industrial chemical, mistakenly mixed in with cattle feed in Michigan in 1973, became the focus of a statewide scandal whose ramifications are still being felt.

More than 32,000 contaminated cows were eventually slaughtered after the presence of PBB was discovered. Traces of the chemical appeared in other animals and foods. As recently as August, quantities of PBB were discovered in the milk of 22 mothers in Michigan.

Public television begins its new season of weekly documentaries tonight with the history of the PBB tragedy. "The Poisoning of Michigan," originally produced by England's Thames Television and slightly re-edited for American broadcast, airs at 10 o'clock on Channel 26 and other public TV stations.

The program opens with heartbreaking scenes of farmers shooting their own sick cattle and goes on to chronicle the origins and the spread of an ecological nightmare. Though the hour is largely populated with the infamous "talking heads" that supposedly make documentaries dull, "Michigan" is in fact alarming and gripping.

After seeing it, one feels even less safe about being a citizen of the '70s.

Reporter John Fielding interviews farmers, scientists and state officials as he puts this sorry story together. The bureaucracy hardly comes off looking blamesless, but the program is less the expose of a cover-up than a lament for the hazards of our age, here made frighteningly specific.

To its credit, the program lets the interviewees have their say without the excessive internal aditing of remarks that mars many American commercial TV news interviews and documentaries. The victims describe the early and late symptoms of PBB poisoning with lucidity.

A mother recalls how she dropped her baby because of her weakened hands. One farmer remembers how his cows became sick: "they were just a mess, they were just a physical mess," he says finally. Even after evidence of the poisoning seemed imposing state agriculture officials would not acknowledge a crisis. Farmers were told their cattle were not "officially sick," as Fielding puts it, because the PBB levels were not considered officially dangerous.

The FDA in Washington didn't act on the problem until about nine months after it was discovered. Asked if it hadn't been brought to the agency's attention earlier, an official says in pure officialese, "To the best of our knowledge, no."

Christie Basham, executive producer of the program for WETA in Washington, said about six minutes was cut from the original documentary, a red in England in March, and that some of reporter Fielding's language has been toned down.

Basham got a letter from Michigan Gov. William Milliken (interviewed on the program) in mid-September, claiming that the program was unablanced. A state lobbyist later presented her with a 12-page critique of show, based on the original and unrevised script, and one or two additional edits then were made, Hasham said.

But she also saids yesterday that no one has actually tried to suppress the program and that public TV stations in Michigan will air it. The PBB scandal is still a hot political issue there, and so public TV station WKAR in East Lansing has provided an hour folloiwng its telecast of the codumentary for Milliken and other state officials to respond. "It's not unusual for a public TV station to do that," a station spokesman said.

"The Poisoning of Michigan," is a dramatic, straightforward documentary on a subject of concern. One could wish that American public television had originated the report rather than merely acquiring it, but that doesn't lessen its impact or significance.