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Comment by hammock | Hacker News Reader

What is the vector for lead exposure from paint? Do we think they are all eating it, or that their parents/landlords are constantly sanding it for some reason and not simply painting over it?

edit: Why am I being downvoted?

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"Most lead poisoning in children results from eating chips of deteriorating lead-based paint" [1].

[1] https://www.mayoclinic.org/diseases-conditions/lead-poisonin...

Right. It doesn't pass the sniff-test that a whole 1/3 of world's children would be getting poisoned through ingesting paint chips. I'm as curious as the GP about what the actual vector is, but it seems that per the article there really is not enough data to say definitively.

My understanding (from growing up in an old apartment with lead and asbestos everywhere) is that, even your children aren't picking lead chips off of the wall, they're being exposed to pulverized paint dust when they e.g. play on the floor. It's apparently especially common when children's rooms have openable windows, since windowsills shed their paint easily.

It's not so much from walls, but dust from joints around windows and doors.

But seriously: we vaporized 200,000 tons a year in gasoline. Where do you think it all went? Places with lots of cars: cities. Definitely do not eat food grown in a city garden- always use raised planters filled with country dirt.

https://archive.epa.gov/epa/aboutepa/epa-requires-phase-out-...

See figure 2 here:

https://www.edf.org/sites/default/files/the-hour-of-lead.pdf

In New Orleans at least, there is a ton of lead in the soil. When I was working for the City, playgrounds were prime targets for remediation.

You shouldn't be. Lead paint in-situ isn't dangerous. Disturbing lead paint is dangerous.

Mitigation/ removal of lead paint is more of a danger than the original risk.

I believe that the major vector indoors is dust coming from the lead paint on windows and window sills. When the wear surfaces rub against each other, a small amount of lead paint dust is created and inhaled or ingested by children.

Outdoors, the problem is the lead dust in the soil. Chickens are getting lead poisoning in urban areas:

https://now.tufts.edu/articles/backyard-chickens-and-risk-le...

Latex paint steadily degrades until it's dust. The breakdown is accelerated by UV light, but the end product of all exposed latex painted surfaces is the same; it chalks, flakes, and steadily emits dust and fine particles into the environment.

Regular re-painting can keep the old paint largely encapsulated, but it's still there waiting for an unsuspecting home owner to sand or scrape it loose while doing repairs or renovation.

Outdoors, that dust contributes to the lead load in the soil around the house. Indoors, it's house dust, which babies and kids are naturally bathed in because they live closer to the floor than adults do, and because they put everything in their mouths. In both cases the vectors of exposure are both oral and by inhalation.

Another big contributor to lead dust in households is older (early 2000's and earlier) vinyl window blinds [1]. Many vinyl products contained lead, and vinyl chalks the same way latex paint does as it degrades.

1 - https://cchealth.org/lead-poison/pdf/miniblinds.pdf

I'm wondering this too, i couldn't find very much information on the actual risk vectors and required exposure levels and concentrations to trigger an increase in lead blood levels, I'm still looking

https://news.ycombinator.com/item?id=29487787

So, lead paint actually tastes sweet, which can explain why kids who don't know better will eat it.

Why do you think lead paint tastes sweet?

The Romans used lead acetate as a sweetener[0], but the exact compounds used in lead paint are different. It doesn't seem that those are sweet.[1]

[0] https://en.wikipedia.org/wiki/Lead(II)_acetate

[1] https://healthyindoors.com/2018/11/lead-paint-sweet-aint/

There are indications that lead acetate (which is only mildly sweet) was occasionally used as a drier in oil-based paints a long time ago. But I've seen no good evidence regarding how common this may have been.

But even if that's true, lead acetate would have been used only in tiny quantities (like any other metallic drier). And lead acetate degrades rapidly, so there wouldn't be any lead acetate left in the paint after a short time anyway.

Normal wear and tear?

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