Most cities of the world have a background level of lead swirling about due to burning leaded petrol even though mostly that was discontinued years ago. Old weatherboard houses often have a region of soil around the bottom of the external walls (this is measurable) because they were painted with lead paint and over the years it has flaked off. Many old houses still have lead paints on the walls inside or outside. Lead batteries and bullets introduce lead into the environment. There are a great many ways to be exposed to lead.
There are many other pollutants in our environment. To take just one: many millions of people have shorter lives and are less healthy due to airborne particulate pollution from vehicles, power stations and factories. Yet we still drive billions of ICE vehicles, burn coal and gas in vast amounts and do industrial processes in every city.
If you want to do something useful take up arms against these big polluters that demonstrably do much harm and leave drinking out of hoses down near the bottom of the list where it belongs.
