From yesterday's Chron, some action on the clean-air front.
Concentrations of a dozen air pollutants in the Houston area pose significant risks to public health, and nowhere is the risk greater than in east Harris County, along the Ship Channel, a task force of public health and toxicological experts convened by Mayor Bill White concluded Monday.
In a city that ranks as one of the most polluted in the nation, the study provides, for the first time, a "to-do" list for reducing pollution, based on the risk to Houstonians' health, the mayor said.
"There is a myth that we need years and years more study before we take action against polluters ... we know enough now to know there is significant risk to our population," said Mayor Bill White, who convened the task force in March 2005, after reports by the Texas Commission on Environmental Quality and the Houston Chronicle exposed high levels of pollution in some city neighborhoods.
The landmark 58-page report evaluates 179 chemicals that are released from car tailpipes, ships, industrial plants, and small sources such as dry cleaners and gasoline stations, for their potential to cause cancer, lung disease and other ailments.
The quality and quantity of information available on each chemical varied. In some cases, the scientists relied on computer projections of pollutant concentrations based on emissions in 1999. In others, they used data on 50 pollutants collected by 20 monitors in the Houston area in 2004. In the end, according to Dr. James T. Willerson, president of the University of Texas Health Science Center, which led a committee of eight scientists from five different institutions, the rankings came down to scientific judgment.
The 12 riskiest compounds contain some usual suspects, such as ground-level ozone, the main ingredient in smog, and the fine particles in diesel exhaust and soot. But the bulk of the list comprises more obscure, toxic chemicals like ethylene dibromide, acrolein, and chromium VI, that are difficult to monitor and do not have federal health standards.
The mayor said the report would be used almost immediately to develop a regional plan that would focus on specific neighborhoods and sources. The first step is targeting the chemical benzene in the Clinton Park/Tri-Community and the Harrisburg/Manchester neighborhoods on the city's east side, the most polluted of the region's 895 census tracts. Though the bulk of the city was exposed to three or fewer of the 12 chemicals identified, the 28 tracts in east Harris County had three or more pollutants at concentrations posing a definitive health risk.
"There are some sad results of this study ... of the disproportionate impact of pollution," White said.