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Posted by 254wu1d7
 - January 21, 2011, 12:28:18 PM
“Mercury is toxic and is most detrimental to children and                pregnant women and causes developmental abnormalities,” Lefer                said. “Mercury emissions from coal and other sources are going                to be more problematic to reduce, but using cleaner fuels and alternative                energy for electricity will reduce the mercury levels in the environment.”
                        
            
            
            
The Texas Air Quality Study-II wasn’t all doom and gloom for                Houston,You are not allowed to view links. Register or Login, though. Houston does have a serious ozone problem, but                efforts to fix it are headed in the right direction.
The base for embalming fluid, formaldehyde is believed to be the                catalyst in the production of ozone, a harmful pollutant that may                be primarily emitted from traffic and poorly maintained diesel cars,                and secondarily by chemical reactions in the atmosphere.
Air Quality Study: Mercury and Formaldehyde Found In Houston, Texas Air
            
            
“The bad news is that Houston’s ozone levels are above                the Environmental Protection Agency’s (EPA) standards for                30 to 40 days each year,You are not allowed to view links. Register or Login,” Lefer said. “The EPA allows                a city to have one to three ‘bad’ ozone days per year.                So we are well above this average. But, the good news is that the                number of ‘bad’ ozone days each year in Houston is decreasing.                In addition, the peak ozone values observed in Houston have also                been on a down trend the past six years. We still have a long way                to go, though.”
The UH Atmospheric Science group is working on calculations to                assess the impact of primary formaldehyde emissions in producing                ozone in Houston. They hope to have the results in time for conferences                in December and January.
Scientists know mercury is emitted mostly from coal-burning power                plants, such as the one in Sugar Land, but there is additional mercury                coming from the area around the Houston Ship Channel and the nearby                refineries and petrochemical plants,You are not allowed to view links. Register or Login, according to the study. The                more than 100 scientists from UH and research institutions across                the country who pored over the air quality data are still analyzing                the information to identify what industrial processes are producing                the mercury.
Most of the data was collected from the UH Moody Tower Atmospheric                Chemistry Facility, an 18-story building that is operational 24                hours a day, seven days a week, and from data collected from various                aircrafts and a National Oceanic Atmospheric Administration ship                in the Houston Ship Channel.
“Primary formaldehyde means it is directly emitted to the                atmosphere,” Rappenglueck said. “Secondary formaldehyde                means that it is chemically formed in the atmosphere from other                chemicals.”
The Moody Tower facility measured three different types of mercury:                gaseous elemental mercury, reactive gaseous mercury and fine particulate                mercury. Although traces of mercury have been found all over the                country, the amounts detected varied from double to more than six                times what is typically found in other parts of the United States,                Lefer said.
Formaldehyde emissions from automobile exhaust are directly emitted                into the atmosphere, but their contribution is small, Rappenglueck                said. Instead, the air quality data suggests there may be a “new”                source of primary formaldehyde emissions in Houston.
Although Houston’s air quality has improved from previous                years, the Texas Air Quality Study-II, a 45-day study conducted                in 2006, is the first to provide solid mercury measurements in Houston,                according to Barry Lefer and Bernhard Rappenglueck, UH professors                of atmospheric science.
“Once the source of the formaldehyde is identified,You are not allowed to view links. Register or Login, it should                be possible to figure out how to reduce these emissions,”                Lefer said. “Formaldehyde is not toxic at these levels, but                it is very efficient at producing ozone pollution. We think this                is one of the ‘missing’ links in understanding Houston’s                ozone pollution.”
“Formaldehyde has been measured before in Houston’s                air, but, to the best of my knowledge, mercury has not been measured                in Houston,” Rappenglueck said. “There is now a significant                amount of formaldehyde and mercury in the air here at times.”