A major attempt to streamline-or, critics claim, politicize-the revision of important air-quality standards has run into trouble. One year ago, the U.S. Environmental Protection Agency (EPA) overhauled its lengthy process of updating the National Ambient Air Quality Standards (NAAQS), which have far-reaching impacts on many regulations. Some critics feared the move would allow politics to trump science by giving agency appointees more say and sidelining external scientific review.

Ariyalur, the land of fossils, is found to be embedded with rich limestone deposits. Hence around 9 cement factories have been established in and around Ariyalur. This becomes one of the source of air pollution in this area.

People have always been proficient at making trash. Future archaeologists will note that at the tail end of the 20th century, a new, noxious kind of clutter exploded across the landscape: the digital detritus that has come to be called e-waste. More than 40 years ago, Gordon Moore, co-founder of the computer-chip maker Intel, observed that computer processing power roughly doubles every two years. An unstated corollary to "Moore's law" is that at any given time, all the machines considered state-of-the-art are simultaneously on the verge of obsolescence.