John Oliver is known for using Last Week Tonight‘s 20-minute closing monologue extravaganzas to tackle issues that most satirists (and, frankly, many journalists) won’t even touch, and Sunday’s show was a prime example.

The crisis in Flint, Michigan — brought on by untreated water corroding the city’s ancient pipes — is just the tip of America’s lead iceberg. Millions of disproportionately poor people around the country are exposed to lead every day from things like untreated paint in old buildings. Even after clean drinking water starts flowing into Flint homes again, lead poisoning will continue at shameful rates around the country, mostly in other underserved communities.

The same politicians who so vocally expressed their outrage at Michigan’s Republican governor have done very little over the years to address the full picture of lead poisoning in America, and John calls on Sesame Street’s Elmo, Rosita, and Oscar to point out the obvious: If we want to end lead’s awful legacy in America, “first, we all have to care!”

Photo and Video: Last Week Tonight with John Oliver.