One of the most dangerous forms of lead is Tetraethyllead, because of how fat soluble it is. It's been banned in nearly every country in the world because it moves through the environment at an alarming rate. One company in the world still manufactures it, and they're based in the UK[0].
They're entirely aware that they're killing people and have openly said in management meetings that they won't stop manufacturing the product until government regulation forces them to.
Mind you, lead levels don't only increase in the country the chemical is used; it moves through entire ecosystems and across oceans. Lead levels don't fall to below dangerous levels for decades. This isn't just poisoning the people nearby; it's poisoning the entire world in small, insidious ways. And chemical companies are profiting from that. The margin they're selling TEL for would make government contractors cry.
And to top it off, they have virtually no quality program surrounding their products because they don't need one; all of their deals are done with backroom handshakes and agreeing to take the blame if an issue arises. Their company is built around the idea that it actually costs less to just say "Yeah, we're terrible people, fine us" than to actually try and comply with government regulation. They've repeatedly been caught in corruption and environmental probes, and have changed their names in the states and in the UK multiple times. They were literally caught trying to bribe their way into selling TEL in Iran. [1]
[0]: https://www.independent.co.uk/environment/leaded-petrol-alge...
[1]: https://www.sfo.gov.uk/2014/08/04/four-sentenced-role-innosp...
[1]: https://www.sfo.gov.uk/cases/innospec-ltd/