Brett Wilkins is a San Francisco-based freelance author and editor-at-large for US news at Digital Journal. His work, which focuses on issues of war and peace and human rights, is archived at www.brettwilkins.com.
That stretch of roughly 85 miles, widely known as "Cancer Alley," is home to dozens of refineries and chemical plants and to many predominantly Black communities.
The figure, delivered under questioning at a hearing repeatedly interrupted by protesters, marked an increase from the last official estimate and drew immediate criticism from Democrats on the committee.