How do you think people get cancer? Well they drink too much benzene. Well gasoline causes cancer too full of carcinogens. if you smell it your exposed. burned fuel is actually better assuming it’s 100% burned. Some distillation towers n oil refinery. they produce a dozen oil products. idk if they cause cancer if you eat/drink them .
Peole might also have breathed the fumes of low quality benzene-burning cars on the streets. less likely tho. It gets incorporated into tissues of plants that you subsequently eat, or in the case of cigarettes, tobacco. That's why tobacco packs come with warnings that the juicy benzene in the leaves will show you a good time .
Same deal with lead. People pound back chocolate, cocoa, coffee and other shit grown exclusively in countries where all the farm equipment is still using leaded gasoline even today! Reports of people in US and Europe getting lead poisoning from eating that shit. Unbelievable but true. Gotta watch where the shit you eat comes from and get checked for lead levels if you are hooked on those things.
It's all about the profits and no regulation in some of these countries. They use ancient equipment and fuels terracore, whatever is absolute cheapest because they get pennies per pound for all that crap so they cut on all costs.