Asking for the binary "do you currently have a gas stove?" elides a lot of important information. People move around. A previous residence with a poorly ventilated gas stove can cause lasting damage that persists after you move somewhere else. As it did in my case. The A/(A+B) * B/(B+D)

calculation could just as easily be an underestimate as an overestimate. I avoid gas stoves in new residences BECAUSE of my asthma, so I personally contribute to making that calculation more underestimate-y

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You write that the PAF is A/(A+B) * B/(B+D) where

A.) gas stove, no asthma

B.) gas stove, asthma

C.) no gas stove, no asthma

D.) no gas stove, asthma

This formula doesn't make sense to me. Suppose that gas stoves and asthma were completely unrelated: gas stoves happen at random with probability p and asthma happens at random with probability q, independently. Then this formula gives

p(1-q)/p * pq/q = (1-q)*p

when it should give 0.

What am I missing?

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One thing that's definitely wrong is that the formula should be B/(A+B), not A/(A+B), just from the definitions of the four categories. In your example, though, this gives pq.

Perhaps there's supposed to be some additive correction? For example, a formula like B/(A+B)*B/(B+D) - (A+B)(B+D)/(A+B+C+D)^2 [which gives zero in your example] feels more correct.

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Could the birth defect result around induction stoves actually be real? How would that work?

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if it's a real effect, it could be because induction stoves are made from some toxic material not present in gas or electric stoves.

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Jan 23, 2023Liked by Sarah Constantin

Could even be one particular induction stove manufacturer in China, rather than anything general about induction stoves!

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Great stuff, Sarah. Thank you for looking into this -- too bad most people won't get past the headlines.

I linked to your piece in my intro today here:


Cheers 💚 🥃

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As I've said (https://thezvi.substack.com/p/on-cooking-with-gas/comment/12167026), I'm, let's charitably say, really surprised that it is respiratory problems we discuss about the things whose chance to create fires and explosions is noticeably higher.

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I don't think gas stoves _are_ a bigger fire risk than all other types of stoves, e.g. 'electric'. I think induction is (probably) safer, but people routinely produce fires when cooking that are entirely independent of the stove heating technology (e.g. grease fires).

I will absolutely grant that the explosion risk of gas stoves (or any gas appliances) is real but this, from your linked comment on Zvi's post, just seems like ridiculous hyperbole:

> The person who invented the idea of putting gas into houses where people live (as opposed to just using it in factories and power plants) has probably indirectly killed more people than Hitler by now.

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Well, it is a hyperbole in that I didn't actually do the calculation, but I wouldn't be _too_ surprised if it were literally true. Moreover, we're speaking of a thing whose chance of explosion should legitimately be around zero rather than routinely happening every year like clockwork: these are cooking appliances not bombs.

As for electric stove fire vs. gas stove fire... you can't and won't remove all electric appliances from your home, and addition of the stoves specifically doesn't add that much risk to electricity-based fires (the independent-of-technology fires are a different beast but they cancel out by definition of being independent). Gas-related fires, on the other hand, are an entirely new and independent risk fully added to the already present electricity-risk (by the usual P(AorB)=1-(1-P(A))*(1-P(B)) calculation for independent events). So... no, I don't buy that gas stoves aren't a higher fire risk.

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I find it unlikely that gas stoves could actually cause asthma. Asthma is a disease of chronic inflammation, a disease that is part of the "atopic march" (atopic dermatitis and subsequent allergic rhinitis and asthma) https://pubmed.ncbi.nlm.nih.gov/25419479/.

The single most important predictor, at least for allergic rhinitis but I suspect also for asthma and dermatitis is...surprisingly...birth order. A first born child has a far higher probability of being afflicted with these conditions than a second born one...even in the same household. There is something different that happens in early childhood, only with the first born, that appears to be the primary cause. This is something I plan to write about in detail eventually.

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