Texas freeze led to release of tons of air pollutants as refineries shut

By Laura Sanicola and Erwin Seba NEW YORK/HOUSTON (Reuters) - The largest U.S. oil refiners released tons of air pollutants into the skies over Texas this week, according to figures provided to the state, as one environmental crisis triggered another. Refiners and petrochemical plants along the U.S. Gulf Coast scrambled to shut production as an arctic air mass spread into a region unused to frigid temperatures. The extreme cold, which killed at least two dozen people in Texas and knocked out power to more than 4 million at its peak, also hit natural gas and electric generation, cutting supplie...