Arsenic in Hurricane Katrina wood debris

Hurricane Katrina left behind an estimated 55 million cubic meters (m³) of tangled debris in Louisiana and Mississippi—enough to cover 150 football fields piled 15 meters high. To add to the disposal problem, much of the lumber in those piles contains arsenic, a known carcinogen.

The arsenic comes from chromated copper arsenate (CCA) treatments that were applied to wood to protect it against termites and decay, two big problems in the steamy southeastern U.S. that made the pesticide very popular until recently. To sort the good wood from the bad, a team of researchers led by Helena Solo-Gabriele of the University of Miami used handheld X-ray fluorescence devices to make on-the-ground measurements of arsenic in the New Orleans debris. The results were published today on ES&T’s Research ASAP website (DOI: 10.1021/es0622812).

The team sampled more than 200 pieces of lumber at seven sites in New Orleans, including the hard-hit Ninth Ward neighborhood, where piles of housing still remain untouched. From their measurements in New Orleans, they estimate that in total, Katrina debris in Mississippi and Louisiana contained about 1740 metric tons of arsenic from treated wood.

Arsenic-treated wood was banned in U.S. playground equipment in 2001, and CCA manufacturers and users agreed to work with the U.S. EPA in 2002 to take the pesticide out of residential use. This led to the creation of arsenic-free replacement chemicals, which contain copper, for most applications.

from ES&T News