> It was not proving anything - it was listing things in the literature, of which it listed a significant amount of studies that did conclude significant advers

> It was not proving anything - it was listing things in the literature, of which it listed a significant amount of studies that did conclude significant adverse long term effects. Which of those studies did conclude "significant adverse long term effects"? > A literature review doesn't get to the end and say "Eureka! We proved it!" It gets to the end and says "we have listed current research, and we recommend further stuff for the following reasons". A literature review summarizes the scientific knowledge - it is not merely an index. And as I wrote in my first comment, this summary does not include a link between road dust and long-term adverse health effects.