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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Dear Nikhil<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">I am somewhat taken aback by the titled of this article:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><a href="https://phys.org/news/2017-01-cookstove-pollution-supercomputers-nasa-satellites.html">Research targets cookstove pollution using supercomputers and NASA satellites</a>
<a href="http://Phys.Org">Phys.Org</a> and <a href="http://www.ibtimes.co.uk/scrapping-worst-pollution-emitting-stoves-could-prevent-22-5-million-early-deaths-by-2100-1602626">Scrapping the worst pollution-emitting stoves could prevent 22.5 million early deaths
by 2100</a> International Business Times UK.<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Obviously ‘early deaths’ means ‘premature deaths’. So I am asking you if you consider the concept of ‘preventing a premature death’ a valid concept.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">As the premature deaths were the result of analysing people who were born after 1930 and are already dead, and attributing to their deaths (before some assigned age like 86)
‘causes’, then the concept of ‘preventing a premature death’ seems questionable. As you have pointed out, we do not know what people living today will die of, or whether their deaths will be premature. What will be attributed as causes, the % of each cause,
in future is hard to assure now to the point one could say ‘I prevented this woman from dying prematurely’ when I know nothing about what else there is in the environment that completes with stove smoke.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Would you please consider the validity of an assertion that one can reduce PM<sub>2.5
</sub>exposure from cooking stove smoke for a particular group of people and ‘prevent their premature deaths’. It seems to me the claim founders for the same reasons as the claim to have ‘reduced exposure’ in the first place. Basically the claim is based directly
on a reduction of claimed future exposure.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Thanks<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Crispin<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p> </o:p></span></p>
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