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Comment by ulnarkressty | Hacker News Reader

How could one test for heavy metals in foods at home? Supposedly Indian spices and other plant products coming from there contain non-trivial amounts of lead [0] [1].

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5415259/

[1] https://www.consumerlab.com/reviews/psyllium-supplements/psy...

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First you need to burn the food product for a while to make sure that most of what is left is heavy metals in the ashes. (you typically need a flask for that, and an apparatus to get all the fumes from the burning process safely out).

then from the ashes you need to dissolve them in water (easier said that done), and use reagents based on the type of metal you want to detect from the sample (titration). If you measure accurately the volume of water used to dissolve and the amount of ashes coming from the food product, you can determine a concentration for a specific heavy metal.

Sigma-Aldritch probably sells the reagents you need for heavy metal testing.

Many spices apparently have high levels of heavy metals, I don't know that it's specific to India. There was a study, I think maybe on HN, where they analyzed a bunch of grocery store spice brands and found heavy metals in many.

I know it's not helpful but i get the impression it's not something easy to analyze at home.

With all this stuff (mercury in salmon, toxins in liver, radioactive potassium in bananas), my take is that too much of anything is probably bad an everything is probably fine as part of a varied diet

At least with spices you also need very little, so exposure to heavy metal contaminants through that route would be relatively lower.

Consumer Reports did a widely reported survey last year but it was almost random which spice would be contaminated - one source of herb x would be fine but from a different source it was contaminated. https://www.consumerreports.org/food-safety/your-herbs-and-s... Spices that are colored (i.e. turmeric) are particularly vulnerable. https://pubs.acs.org/doi/full/10.1021/acs.est.9b00744

An XRF spectrometer might work on food.

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