The scandal about lead in the Flint Michigan water supply reminded me of my own brush with lead issues. In the 2000s a program started up in electronics called the Reduction of Hazardous Substances, RoHS. It was intended to get lead out of the solder used to attach chips to boards, and also to get rid of a lot of other dangerous materials like cadmium, hexavalent chromium, and a lot of nasty organics used in plastics.
This was a royal pain for chip makers like my company. The lead-free solders are more expensive and don’t work as well. They can form tiny whiskers of tin that short out adjacent wires. Worse, they don’t have as much give when the chips and boards expand and contract during temperature changes. When a chip heats up under heavy usage, it can easily pop right off the board. Going to lead-free solder almost brought down Nvidia when their latest graphic processor chips started losing connections on customers’ boards, and also almost did in the Xbox 360.
This is also the reason why lead paint is better. Because it has some give, it can stay attached to surfaces through the cold of winter and the warmth of summer. To this day lead paint is more durable than the alternatives, and is still providing good coverage decades after it was taken out of the paint supply.
In the electronics world we grumbled that no one should care if there was a little lead that was tightly encapsulated underneath the chips. It’s not as if it was going to be eaten by children like the sweet-tasting chips of lead paint. But Third Worlders care. All this stuff eventually gets sent to desperately poor places for recycling. When they grind up the boards to recover the gold that’s used in contacts and bond wires, they spread lead everywhere. It’s a nightmare gift from the First World. The EU was the first to actually care about this, and the US and Asia followed, reluctantly. Now we’ve actually adapted to doing without lead, and don’t miss it.
Ultimately we have to get rid of it everywhere. The managers of the Flint water supply thought that the old lead pipes there would be fine, even with the corrosive water from the Flint River going through them. They were wrong, and have now harmed a generation of children there. Every poison is going to hurt somebody, somewhere and someday.