每隔几个星期，我们学习到我们的健康和安全的一些新的威胁。  Many times the danger is genuine and caution is prudent.  But, once in a while, the fear that the announcement generates may be worse than the exposure to the supposed toxin.

We need to examine the source of each study to determine its validity.  Groups with certain words in their names, such as "public" or "earth" or "defense," may not really be what their name implies, and if the only science course their spokesman ever took was political science, then they are more likely to be attempting to advance an agenda than offering a serious scientific study.  Furthermore, some people might be trying to advance a product by creating "public awareness" of some contrived fatal flaw in their competitor's product.