Okay . . . . . now, as laudable an idea as this is, it is really not in the same league as:
Over abstraction
Repeated Sewage pollution
Industrial waste pollution
Road and Farm water run offs
Flooding, and
Pharmaceutical and endocrine disruptors in our rivers
Regardless however, was Prof. Gersberg's research undertaken here in the UK or back in his home State of California, and if so on what species of fish and in what environments; freshwater or saltwater, or both?
Notwithstanding, when I used to smoke I always carried an old Holdorn tin for all of my cigarette butts, and would recommend all smokers to do the same.
In fact my ones had very nicely pained pictures of both Carp and Tench on them.