Not that I have any problem with people seeking to advance the scientific method but one wonders from this commenter’s other posts whether this was a legitimate desire for truth or someone just looking to poke holes in the post…
The person looking for truth will likely go "thanks!" when receiving the clarification or additional info they were searching for.
The person looking to poke holes will move onto the next trumped-up quibble and force someone to knock that down too. Repeat ad infinitum until people get fed up and you can claim victory. (for example: https://news.ycombinator.com/item?id=38968969)
The answer you seek is in the second (short!) paragraph.
> But a new analysis of American data, published in Environmental Science & Technology...