My list now includes:
Sulfur Dioxide
Clean Air Act
Montreal Protocol
Lead Paint
Lead in Gasoline
Public Radio
Mandatory 8th grade education
Secondhand Smoke
Public Transit Subsidy
Automobile Emissions Standards
Fishing Quota System Australia
Bees and Orchards
Cattle Ranchers and Crop Farmers
—
Climate Change
Space Debris
Traffic Congestion
Violent Crime
Assuming the Data is Correct: legal Marijuana
Style suggestion. You could put the penultimate paragraph before the preceding one and delete the final paragraph. That will decrease the preachiness factor at the end and the repetition of ideas in the last and third to last paragraph. Plus going straight from we need serious people to the paragraph about those people is what your structure is asking for.