Hello,
In EF 3.1 method, which uses USEtox, I try to understand the 1,000 factor between :
- [ World Population in 2010 ] x [ NF_Human toxicity, cancer in 2010 ] = 6,895,889,018 persons x 1.73 10^-5 CTUh/person = 1.19 10^5 CTUh
- approx number of new cancers in 2010 = 10^7 to 10^9 (sources: ourworldindata.com and others.)
Reasons I guess :
- CTUh is an estimation of risk over a normed population, while the observed new cancers are observed things.
- all cancers do not come from pollution (e.g. stress, alcohol, background, etc.)
- USEtox may be missing the "cocktail effect" and in some way, the "tipping point" effect
- co-morbidity with other factors
- USEtox is a fantastic tool but of course still many chemicals and other are not yet implemented (e.g. many pfas / pfas, for example)
- ... would EF 3.1 be totally unaccurate here in trying to compute this Normalisation Factor ? and.or uncomplete (for example, could not find Cr (VI), but only chromium and chromium (III).
But, still, I wonder why such a one thousand factor difference. Isn't it huge, even considering above limits ?
Many thanks, it will help alot understanding the correct use of this indicator.
Nice day to all
Dominique