Cigarette filters are essentially made of plastic. Because they're plastic, they're not really degradable.
The biggest issue with smoking on the beach is the litter, not the second hand smoke. I spend a lot of my free time at the beach and cigarette butts in the sand are a constant occurrence. With a generic sea breeze of between 5 to 10 miles per hour, the issue of second hand smoke is not really an issue.
While it's easier to enforce a smoking ban, the right thing to do is to enforce a littering ban.
(FYI: I don't smoke)
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