Singling out yet another under-examined issue from the periphery of the mainstream news cycle—and appealing to the presumed liberal leanings of his primary viewership—the British satirist presented an impassioned 18-minute segment about the ubiquity and dangers of lead poisoning on his HBO talk show Last Week Tonight.

“Lead: it’s the most dangerous thing in Led Zeppelin’s name,” Oliver quipped. “And I will remind you, the other thing was Zeppelin!”

Picking up where headline news left off this year about Flint, Michigan’s water crisis—a health emergency that saw children exposed to contaminated drinking water leading to elevated lead levels in their blood and a litany of health woes—the fake anchorman underscored how lead poisoning has also persisted as a national health crisis for more than two decades.

His aim as always, is Congress members’ hypocrisy and inaction. Oliver shows clips of Rep. Mark Meadows (R-NC), Rep. Tim Walberg (R-MI), and Rep. Jason Chaffetz (R-UT), the Oversight & Government Reform Committee chair, expressing their outrage about Flint. But then makes the point all of them have voted to reduce funding government programs that would eliminate lead from homes.

“Unfortunately, the problem is not just in Flint,” Oliver said. “A USA Today Network report found lead contamination in nearly 2,000 additional water systems spanning all 50 states.”

He added: “We can’t just act like it’s not there, the way we all pretend the public swimming pool is not 3 percent child urine.”

READ: The Tragedy Behind Flint’s Lead Crisis That No One Talks About

Although his tone was jokey, Oliver’s prognosis was stern. Removing every one of the country’s 7.3 million lead service lines would do little to eliminate the contagium of lead poisoning because the larger threat facing American children is the ingestion of lead paint dust, he said.

According to a US Department of Housing report, more than 2 million homes contain both a lead dust hazard and a child under 6-years-old. The Center for Disease Control estimates that over 500,000 kids have elevated levels of lead in their blood. And a child reportedly can be poisoned by as little as 10 milligrams of lead, leading to brain damage or death.

All of which is alarming but not exactly the stuff of great comedy—unless you feed those figures through the host’s pop cultural immersion blender imagination. “Lead is almost as much of a scourge in young children’s homes as Frozen merchandise,” Oliver joked. “‘Why do you need three Olafs and a singing Elsa, McKenzie? Let “Let It Go” go!’”

It begs the question: if lead paint is so dangerous, why is there so much of it in houses where kids live? Short answer: the lead industry made concerted efforts to portray the metal as harmless—even beneficial to health—for more than 50 years.

Cost of getting rid of lead

A 2000 study entitled “Eliminating Childhood Lead Poisoning” pegged the cost of ridding the existing housing stock of lead paint at $16.6 billion per year, every year for a decade. But Oliver made clear the government is nowhere close funding such a measure.

Moreover, he pointed out that lead abatement funding has been going down steadily since 2003. And with HUD only able to fund around half of all applicants for lead abatement grants in 2015, that’s a particular problem for people on the lowest rungs of America’s socio-economic ladder.

“So most people with lead problems are stuck in homes they can’t leave and doing their best to avoid danger,” Oliver said. “Which may sound familiar because it’s the plot of every [expletive] horror movie ever made!”

Sesame Street lesson

And what about Congress members who still aren’t in favor of funding to eliminate this health risk? No episode of Last Week Tonight is complete without a kind of partisan rallying cry. And on Sunday, Oliver traveled to children’s television’s most beloved precinct, Sesame Street (which, incidentally, moved from public television to HBO not long ago), enlisting Elmo, Rosita and Oscar the Grouch to help hit home his point that “we need to care more than we currently do so that we spend enough money on containing” lead poisoning among children.

“How can anyone say it’s too expensive, huh?” wondered Oscar. “Aren’t they aware that according to a study in Environmental Health Perspectives, every dollar we spend on lead paint hazard control produces returns of at least 17 to 1?”

“Wow,” said Oliver. “That is an incredible level of economic insight coming from someone who lives in a trash can.” Then the host and the puppets broke into song.

Watch the full segment here:

Chris Lee is a former staff writer forEntertainment Weekly, The Los Angeles Times, Newsweek and The Daily Beast. He covers entertainment, culture and business in Los Angeles.