Shanna H. Swan

Shanna Swan comes back five years after her first appearance, and the first thing she wants to correct is what that appearance did. The film she has now was originally going to be a movie about plastic. The study inside it did not exist yet when Louis filmed her in New York. What existed was a question Rogan asked her on air, and her answer.

I said, that's my story, and I'm sticking to it.

Then Rogan asked why people did not know about any of this. She went home and thought about that question, and the answer became the Action Science Initiative: short, cheap, high-impact interventions designed to make the problem visible to people who will never read the papers.

Her previous audience had been her peers, in the rooms where everyone had already read the same papers. The public had not been in those rooms. That gap, she says, is what the film and the program are for.

Swan separates three things that get used interchangeably. Plastics have been with us since 1950. Microplastics have been there just as long but were only recognized recently, and measuring them inside tissue is far harder than measuring the chemicals added to plastic. Those additives, the plasticizers, are what her work actually measures.

Phthalates and bisphenol A are the two families she names. Microplastics are a different object: fragments of plastic that carry the additives with them, which is why she describes the harm as double.

what they are is the actual pieces of plastic that carry the plasticizers along

The particle delivers a chemical insult and a physical one, inflammation among them. She puts asbestos and silicosis in the same category: particles that do both kinds of damage. All of it is bad, she says, but none of it is identical, and the distinction matters for what can be measured.

Plasticizers are water-soluble, which is why they end up in urine and why they are comparatively easy to assay. Getting at microplastics in a brain, a testicle or a placenta is a different order of problem.

Rogan offers a case from Austin. Philip Franklin Lee, a Michelin-starred chef with a sushi restaurant there, was chronically exhausted. His hormones came back with very low testosterone. His microplastics came back off the charts.

He then removed plastics from his life as far as he could, stopped drinking out of plastic, and repeated the hormone panel. His testosterone reached 1,200.

With no testosterone replacement, no nothing.

Swan does not treat a single case as proof. She notes that it is the pattern the film follows across several couples, and that the intervention was built to see whether the pattern holds when exposure is deliberately lowered.

Rogan raises the coffee shop. Swan will not name a chain, because she has not tested one. Her suspicion is that the equipment is plastic, and Rogan supplies the detail from the counter: the filter baskets that slide into industrial machines look like plastic trays, and behind them sits a paper filter.

The paper cup is its own source. Its lining is where bisphenols live, which is why the drink arrives with contamination from both ends of the process. Bringing a steel thermos removes one of them, not both.

Pods get their own example. Bruno, one of the men in the film, was attached to his machine and refused to give the pods up, then gave them up anyway. He and his partner have since had two children. Swan is careful: she is not claiming causation, only contribution.

Rogan's own version of the story is the fatigue he kept hearing about, the testosterone panels, and the fact that a friend's numbers moved after the plastic came out of his kitchen and his routine.

The couples in the film were recruited out of a semen-testing company called Fellow, spun out of UCSF, which by then had roughly 200,000 men in its files. Two questions made the study possible: whether a man would agree to be recontacted for research, and why he had wanted the test in the first place.

If the answer was infertility or subfertility, and the problem had persisted more than twelve months, the man was technically infertile and potentially eligible. That still left a long screening process. Couples had to consent to being filmed. They had to fit a term Swan dislikes, idiopathic infertility: no known cause. Neither partner could be obese or a smoker, and no diagnosis was allowed to explain the problem, because an explained case defeats the design.

They had to be couples, still together for the following three months, and not doing IVF. Six made it in; one dropped out for personal reasons.