"The article named the 12 industrial plants in the Houston area that were responsible for the most pollution from upsets - accidental releases that are above what is allowed by the state each year." Upsets are controversial because they often go unpunished and unchecked. The upsets of these twelve plants accounted for 80 percent of the pollution around Houston in 2003. However, only a handful had violations or received fines. Statewide, only 2.6 percent were enforced.