8 ms·

I think this says more about the guidance level than the soil quality. In fact I think it makes things worse rather than better. Continually ratcheting up the

I think this says more about the guidance level than the soil quality. In fact I think it makes things worse rather than better. Continually ratcheting up the safety level to spur continuous improvement is great in principle. But what I think this does in practice is mean that people are no longer able to evaluate soil lead levels appropiately. What does 400ppm mean versus say 1600ppm? They are both "bad" according to the US EPA now but one is clearly worse. If 10% of soil area is above your limit it is easier to allocate your limited resources to fix it than if 25% is. At 25%, with the same resources maybe you just throw up your hands and walk away from the problem. There's similar problems with air quality limits. When the WHO says there is "no safe limit" they simulatenously misunderstand odds ratios and give a lot of people a great excuse to stop worrying about a problem they now think is unfixable.

refurb 2y ago
This is a very insightful comment. Analytical techniques have rapidly improved over the past few decades. Our limit of detection has gone from tens of parts per million (ppm) to fractions of parts per trillion (ppt) for many analytes. That's a million fold better detection level. So in the past you might test drinking water and say there is no lead present. You test using techniques today and you'll find lead is present. But the level hasn't changed. At the sensitivity of parts per trillion you'll find the presence of toxins in damn near everything. People forget that toxins like lead, arsenic are naturally occurring. And pushing "acceptable levels" down as detection improves needs to be done based on proven biological effect, not "no level is safe".
- ImaCake 2y ago
  I think these guidelines are also a political problem. They need to balance risk, communication, and what is feasible given the resources available and threat level. That’s not an easy thing to do. Still I am deeply skeptical that the people publishing these guidelines are considering these aspects effectively when their lead guideline puts 25% of residential areas in the US “at risk”.
  - refurb 2y ago
    The EPA's position is "there is no safe level of exposure to lead" in drinking water. But the question is - is that based on science? And if detection methods continue to improve, will we hold to that statement? Will we tell people not to drink water that contains 0.00001 parts per trillion? There clearly is some level of lead exposure where the level of effect cannot be distinguished from an individual not exposed.
    - Anotheroneagain 2y ago
      You will always see a difference, because it's essential, so every little but makes you less deficient. That is all they did, they never determined which way it is better. It's only assumed to be better - that the protein won't get activated is better, the way you look is supposedly better, the way you think is supposedly better. Even though people got ugly, sick, and the world is in "polycrisis"
    - notjulianjaynes 2y ago
      A blood lead level of 1 ug/dl is enough to increase ADHD symptoms in children[1]. Children absorb lead more readily than adults and lead bioaccumulates. The CDC's action level for childhood BLL is 3.5ug/dl. 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4892926/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4892926/
      - refurb 2y ago
        Holy uncontrolled confounding factors Batman!
      - Anotheroneagain 2y ago
        No. Look at the actual results - the problematic behavior peaks at 5mcg/dl. They are simply too disabled to be impulsive below that. Ritalin actually appears to replace or allow an otherwise lead dependent process.
- yjftsjthsd-h 2y ago
  Two options: 1. People drink water containing let's say 1 part per trillion lead. We test it, we can't measure that, we say it's fine. The people drinking it are in fact fine. 2. People drink water containing let's say 1 part per trillion lead. We test it, we can't measure that, we say it's fine. The people drinking it incur brain damage, but because we can't measure the thing causing it, we don't correlate it with anything. How do we distinguish these cases?
  - Anotheroneagain 2y ago
    Lead is an essential nutrient. Among other things, it's essential for calmodulin, which is a highly conserved protein. There is no eucaryotic life without it. This, and the absence of other "heavy metals" is incorrectly blamed on global warming.
    - vibrio 2y ago
      Interesting. Can you point me to further reading on essential heavy metals in eukaryotes and what is understood about the the dietary levels needed?
      - Anotheroneagain 2y ago
        https://pubmed.ncbi.nlm.nih.gov/10996673/ https://pubmed.ncbi.nlm.nih.gov/10996673/
        vibrio 2y ago
        Thanks for this. Interesting and surprising, that Pb ++ can substitute so well for Ca ++ in calmodulin. Do you have any thing supporting lead being an essential nutrient? I've not seen anything here or searching showing Lead is essential for eukaryotic life, and that is what I'm really interesting in exploring. Also, understanding the mechanism of any lead toxicity in the context if its essential functions would be of great interest.
        2y ago
- mlyle 2y ago
  The level chosen seems like a reasonable level to put up a flag. 200ppm is a level where an active gardener could cause excess exposure by growing leafy vegetables-- so that being the point where you warn people there's a potential problem and they should consider where to plant and what to grow. If you told me my soil lead content was 200ppm, I would change my gardening practices and-- even though it may be a little overprotective-- cover contaminated soils where my kids play most. (Now, if you told me that only 1/8th of homes would be affected if you set the level to 250ppm, maybe I'd say 250ppm would be a more appropriate level to balance the number of people warned; but if it's not a huge increment in the number warned, 200ppm seems appropriate-- that is, the tradeoff isn't just between direct harms and direct benefits but also, as grandparent seems to state, in helping people judge relative levels of risk accurately).
  - Anotheroneagain 2y ago
    But what amounts to excess exposure is also getting lowered all the time. Also people grew lettuce to obtain lead. People like the taste of foods high in heavy metals, their absence is the reason why vegetables turned into tasteless plant mass.
Anotheroneagain 2y ago
It's total madness. People got violent because iron is toxic (the entire civilization collapsed when it was discovered). Lead and other heavy metals are essential. They got it entirely the other way round, including the measurement of intelligence. Patterns, rules and categories are compensatory mechanisms for the absence of understanding.

refurb 2y ago

This is a very insightful comment. Analytical techniques have rapidly improved over the past few decades. Our limit of detection has gone from tens of parts per million (ppm) to fractions of parts per trillion (ppt) for many analytes. That's a million fold better detection level. So in the past you might test drinking water and say there is no lead present. You test using techniques today and you'll find lead is present. But the level hasn't changed. At the sensitivity of parts per trillion you'll find the presence of toxins in damn near everything. People forget that toxins like lead, arsenic are naturally occurring. And pushing "acceptable levels" down as detection improves needs to be done based on proven biological effect, not "no level is safe".

ImaCake 2y ago
I think these guidelines are also a political problem. They need to balance risk, communication, and what is feasible given the resources available and threat level. That’s not an easy thing to do. Still I am deeply skeptical that the people publishing these guidelines are considering these aspects effectively when their lead guideline puts 25% of residential areas in the US “at risk”.
- refurb 2y ago
  The EPA's position is "there is no safe level of exposure to lead" in drinking water. But the question is - is that based on science? And if detection methods continue to improve, will we hold to that statement? Will we tell people not to drink water that contains 0.00001 parts per trillion? There clearly is some level of lead exposure where the level of effect cannot be distinguished from an individual not exposed.
  - Anotheroneagain 2y ago
    You will always see a difference, because it's essential, so every little but makes you less deficient. That is all they did, they never determined which way it is better. It's only assumed to be better - that the protein won't get activated is better, the way you look is supposedly better, the way you think is supposedly better. Even though people got ugly, sick, and the world is in "polycrisis"
  - notjulianjaynes 2y ago
    A blood lead level of 1 ug/dl is enough to increase ADHD symptoms in children[1]. Children absorb lead more readily than adults and lead bioaccumulates. The CDC's action level for childhood BLL is 3.5ug/dl. 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4892926/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4892926/
    - refurb 2y ago
      Holy uncontrolled confounding factors Batman!
    - Anotheroneagain 2y ago
      No. Look at the actual results - the problematic behavior peaks at 5mcg/dl. They are simply too disabled to be impulsive below that. Ritalin actually appears to replace or allow an otherwise lead dependent process.
yjftsjthsd-h 2y ago
Two options: 1. People drink water containing let's say 1 part per trillion lead. We test it, we can't measure that, we say it's fine. The people drinking it are in fact fine. 2. People drink water containing let's say 1 part per trillion lead. We test it, we can't measure that, we say it's fine. The people drinking it incur brain damage, but because we can't measure the thing causing it, we don't correlate it with anything. How do we distinguish these cases?
- Anotheroneagain 2y ago
  Lead is an essential nutrient. Among other things, it's essential for calmodulin, which is a highly conserved protein. There is no eucaryotic life without it. This, and the absence of other "heavy metals" is incorrectly blamed on global warming.
  - vibrio 2y ago
    Interesting. Can you point me to further reading on essential heavy metals in eukaryotes and what is understood about the the dietary levels needed?
    - Anotheroneagain 2y ago
      https://pubmed.ncbi.nlm.nih.gov/10996673/ https://pubmed.ncbi.nlm.nih.gov/10996673/
      - vibrio 2y ago
        Thanks for this. Interesting and surprising, that Pb ++ can substitute so well for Ca ++ in calmodulin. Do you have any thing supporting lead being an essential nutrient? I've not seen anything here or searching showing Lead is essential for eukaryotic life, and that is what I'm really interesting in exploring. Also, understanding the mechanism of any lead toxicity in the context if its essential functions would be of great interest.
        2y ago
mlyle 2y ago
The level chosen seems like a reasonable level to put up a flag. 200ppm is a level where an active gardener could cause excess exposure by growing leafy vegetables-- so that being the point where you warn people there's a potential problem and they should consider where to plant and what to grow. If you told me my soil lead content was 200ppm, I would change my gardening practices and-- even though it may be a little overprotective-- cover contaminated soils where my kids play most. (Now, if you told me that only 1/8th of homes would be affected if you set the level to 250ppm, maybe I'd say 250ppm would be a more appropriate level to balance the number of people warned; but if it's not a huge increment in the number warned, 200ppm seems appropriate-- that is, the tradeoff isn't just between direct harms and direct benefits but also, as grandparent seems to state, in helping people judge relative levels of risk accurately).
- Anotheroneagain 2y ago
  But what amounts to excess exposure is also getting lowered all the time. Also people grew lettuce to obtain lead. People like the taste of foods high in heavy metals, their absence is the reason why vegetables turned into tasteless plant mass.

Anotheroneagain 2y ago

It's total madness. People got violent because iron is toxic (the entire civilization collapsed when it was discovered). Lead and other heavy metals are essential. They got it entirely the other way round, including the measurement of intelligence. Patterns, rules and categories are compensatory mechanisms for the absence of understanding.