He is program host and writer of TV documentaries produced by New York-based EnviroVideo including the award-winning Chernobyl: A Million Casualties, Three Mile Island Revisited, Nukes in Space: The Nuclearization and Weaponization of the Heavens and The Push to Revive Nuclear Power.
He has been chief investigative reporter for WVVH-TV on Long Island. He was a nightly news anchor at WSNL-TV and hosted "Long Island World" on WLIW-TV.
He is a regular contributor to Internet sites including CounterPunch, OpEdNews, Enformable, NationofChange and The Huffington Post.
His weekly column appears in The Southampton Press, The East Hampton Press, The Sag Harbor Express, The Shelter Island Reporter, South Shore Press, Sound Observer and in other Long Island newspapers and on news websites on Long Island including Smithtown Matters, RiverheadLOCAL and SoutholdLOCAL.
Grossman writes a blog for The Times of Israel.
He writes for the Manhattan Jewish Sentinel, Long Island Jewish World and The Jewish Tribune.
Grossman was an investigative reporter as well as columnist for the Long Island Daily Press, a major daily newspaper serving metropolitan New York. With the demise of the paper in 1977, he continued to do investigative journalism in books, magazines and newspapers, on radio and TV and, in recent years, on the Internet.
He has done commentary on WRCN-FM and WLIU radio stations, and reported for WBAI radio.
His books include: Cover Up: What You Are Not Supposed to Know About Nuclear Power; The Wrong Stuff: The Space Program's Nuclear Threat to Our Planet; Power Crazy: Is LILCO Turning Shoreham into America's Chernobyl?; The Poison Conspiracy; and Weapons in Space.
He has given presentations at colleges and universities in the United States and abroad and at other venues including the United Nations in New York and Geneva, the British Parliament, the Russian Academy of Sciences and the Second All-Russia Congress on Protection of the Environment.
Awards he has received for investigative reporting include the George Polk, Generoso Pope, James Aronson and John Peter Zenger awards. He also has received citations from the New York Press Association, Press Club of Long Island, Society of Professional Journalists, Psychologists for Social Responsibility, Citizens Campaign for the Environment, New York Civil Liberties Union, Long Island Coalition for Fair Broadcasting, Citizens Energy Council and Friends of the Earth. His TV documentaries have received Gold and Silver awards at the WorldFest-Houston International Film Festival and other honors. His journalism has been repeatedly cited by Project Censored, the media initiative at Sonoma State University, as involving the most “under-reported” issues.
He was the principal founder in 1974 and the first president of the Press Club of Long Island.
At the State University of New York College at Old Westbury he has taught courses including: Investigative Reporting; Environmental Journalism; Politics of Media; Introduction to Journalism; TV and Radio Journalism; and TV Documentary: Theories and Techniques. He also supervises an Internship in Journalism and Media program placing students at media throughout the metropolitan New York Area.
He was honored in 2003 at the State University of New York "Chancellor’s Recognition Dinner Honoring Research and Scholarship in the Humanities, Arts and Social Sciences."