I'm aware of a couple of studies either done by or in association with Dr Jed Fahey (then of Hopkins) showing that sulforaphane intake can cause excretion of benzene, which comes from air pollution. Sulforaphane, an isothiocyanate, triggers the NRF2 system. The 'in association with' studies were done in China (air pollution can be pretty bad there), and the end results were reduction in severity of autism (one study) or schizophrenia (another). The benzene data is from monitoring metabolites in the urine.

I got to wondering if this might also be protective against cancer, went for a bit of a search, and came up with Mechanisms of Action of Isothiocyanates in Cancer Chemoprevention over at PubMed.

Evidence suggests that isothiocyanates exert their effects through a variety of distinct but interconnected signaling pathways important for inhibiting carcinogenesis, including those involved in detoxification, inflammation, apoptosis, and cell cycle and epigenetic regulation, among others.

Broccoli sprouts are the second-highest source of sulforaphane (the seeds are higher but they also contain erucic acid — the sulforaphane in supplements come from there, with the erucic acid removed. Sprouting does the same).

That said, sulforaphane is not the only isothiocyanate. Moringa ‘trees’ also have one, ‘moringin’. (that from listening to an interview with Dr Fahey)

Disclaimer: I started sprouting broccoli based on the pubs of Dr Rhonda Patrick, over at her foundmyfitness.com (I was focused on anti-inflammatory effects as that might lower my risk of AD — but no data there). I’m a ‘subscriber’ there, primarily for their work in education.

TL;DR: maybe add cruciform vegetables to the list of things that are potentially cancer-protective