Joel A. Spivak, 75, who was a popular Washington radio personality before becoming press secretary for the nonprofit Campaign for Tobacco-Free Kids, died March 4 at his home in Alexandria.

Mr. Spivak had metastatic cancer, the result of a decades-long smoking habit.

The son of the 1940s big-band leader Charlie Spivak, the younger Spivak got his start in radio as a disc jockey and talk-show host in some of the country’s biggest markets.

In 1996, after a long radio career — and after he had quit smoking — he joined the Campaign for Tobacco-Free Kids and helped direct media coverage for the nonprofit group.

Mr. Spivak was a forceful voice against the tobacco industry, said Julia Cartwright, an executive at the anti-tobacco American Legacy Foundation.

“He was so passionate about wanting to make sure the next generation of kids wouldn’t grow up to smoke and lose their lives to it,” Cartwright said, noting that Mr. Spivak was motivated by his own past tobacco use.

He became such an effective spokesman in large part because of his previous career in radio. He moved to the Washington area in 1980 as a talk-show host for WRC-AM and was best known for his signature introduction, “This is Joel A. Spivak speaking.”

Washington Post writer Roger Piantadosi called Mr. Spivak’s show an enjoyable departure “from the relentlessly upbeat, carefree, trouble-free, commercial-free aural cheese spread of the ever-insidious phenomenon known to some as safe programming, to others as McRadio.”

In 1983, Mr. Spivak was voted most popular talk-show host by Washingtonian magazine. A year later, he moved to San Francisco and spent two years there as a radio personality before moving back to Washington to become an anchor on WRC-TV (Channel 4) in 1987.

Announcing Mr. Spivak’s hire, the station’s general manager, Jerry Nachman, told The Post: “Given the reluctance on our part to put the toothy, blond, stylistic, unoffensive, white-bread news talent on the air, this guy was destined.”

He was a co-anchor for the “Live at Five” news show on NBC for one year. Station managers said bringing him to television had been an experiment to boost ratings that ultimately failed.

Mr. Spivak then moved back to radio full time as a talk-show host for WRC-AM. One of the subjects he sometimes spoke about on the air was smoking and its relation to health.

John F. Banhaf III, a law professor at George Washington University and past director of the anti-tobacco group Action on Smoking and Health, said he would call into Mr. Spivak’s show for “battle royales” debating “whether smoking caused diseases.”

Banzhaf described Mr. Spivak as an “ardent smoker’s rights person,” who once said that smoking had not harmed his health.

“I said to him, ‘Joel, I can tell from over the phone that you have incipient emphysema,” Banzhaf said, attributing Mr. Spivak’s breathy sound to his smoking. “His voice was his dinner — his pride and joy. That really shook him.”

It wasn’t long after their conversation, Banzhaf said, that Mr. Spivak quit smoking and joined the Campaign for Tobacco-Free Kids.

Joel Allyn Spivak was born on April 22, 1935, in New York. He began his career in the late 1950s as a disc jockey in various cities before becoming a TV reporter and radio personality in Philadelphia from 1968 to 1980.

His marriages to Ann Diamond and Dorsa Russell ended in divorce.

Survivors include his wife of 11 years, Ann Decker Spivak of Alexandria; three children from his first marriage, Amanda Barrett of Gaithersburg, Matthew Spivak of Skopje, Macedonia, and Jonathan Spivak of Santa Cruz, Calif.; a brother; and four grandchildren.

As a disc jockey and radio personality in Houston in the late 1950s, Mr. Spivak admitted that he was willing to take calculated risks for the enjoyment of his listeners.

According to the 2007 book “Something in the Air” by Washington Post journalist Marc Fisher, Mr. Spivak agreed to join the trapeze artists of a traveling circus on the condition that his life be insured with Lloyd’s of London for $1 million.

On the night of the event, Mr. Spivak, dressed in green sequin tights, sailed through the air on the trapeze swing but missed his mark. The arena was silent as he fell. Luckily, he landed with a bounce in the safety net, and the crowd cheered.

It was only after his feet were back on the ground that his boss told him Lloyd’s had refused to insure the stunt.