Nine major public health organizations have one request for Major League Baseball: Ban tobacco.

Leaders from the American Cancer Society, American Heart Association, American Lung Association, American Medical Association and others joined forces this week to write a letter to MLB commissioner Bud Selig and the executive director of the Major League Baseball Players Association Tony Clark.

In the letter they mourn the loss of Hall-of-Famer Tony Gwynn and urge the MLB to agree “to a complete prohibition on tobacco use at ballparks and on camera.”

“As so many in baseball and in the media have expressed, Tony Gwynn was a true hero. We are deeply saddened that his life was ended far too soon by cancer that he attributed to his longtime use of chewing tobacco,” the leaders wrote.

“Use of smokeless tobacco endangers the health of Major League ballplayers. It also sets a terrible example for the millions of young people who watch baseball at the ballpark or on TV.”

Gwynn, who played for the San Diego Padres, was diagnosed with cancer in his salivary gland in 2010. He died on June 16 at the age of 54.

Gwynn was one of many professional ball players to use chewing tobacco. Studies show about 30% of major and minor league players use smokeless tobacco, though rates have been declining since the late 1990s.

In 2011, the league implemented its first rules related to smokeless tobacco products. The rules prohibit teams from providing tobacco to players and prevents players from carrying tobacco tins in their uniforms or doing interviews while using chewing tobacco.

Yet the players’ union stopped short of banning tobacco use on the field.

“These (rules) are not sufficient to eliminate smokeless tobacco use in public settings or to prevent more players from becoming addicted to these deadly products,” the public health organizations wrote in their letter.