The largest U.S. oil refiners released tonnes of air pollutants into the skies over Texas this past week, according to figures provided to the state, as one environmental crisis triggered another. Shutdowns led to the refineries flaring, or burning and releasing gases, to prevent damage to their processing units. "These emissions can dwarf the usual emissions of the refineries by orders of magnitude," said Jane Williams, chair of the Sierra Club's National Clean Air Team. Exxon blamed the shutdown of two Texas refineries on the freezing weather and loss of natural gas supplies. Final figures on pollution releases are due to be submitted to the state in two weeks.

Source: CBC News February 21, 2021 12:45 UTC