Vials and pipette on a lab bench
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  1. PPM is a concentration unit
  2. The analysis needs a method
  3. Do not confuse precision with relevance
  4. Practical conclusion

PPM is a concentration unit

PPM means "parts per million." In discussions about DDW, it is used to express the concentration of deuterium. A lower value describes less deuterium compared to a reference, but it does not alone establish the quality or effect of a product.

The analysis needs a method

Laboratories can use specialized isotopic techniques to compare the composition of a sample. For the reader, the important aspect is the existence of an identified method, an analysis report, and a clear link between the result and the commercialized batch.

Do not confuse precision with relevance

A result can have many decimal places and still not answer a health question. Analytical precision says something about measurement; clinical relevance would require well-designed human studies.

Practical conclusion

PPM is a composition information. Read it as a technical indicator, not as an automatic efficiency or "purity" scale.

Disclaimer: This material is educational. It does not diagnose, treat, or replace the recommendations of a health professional.
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