Aquarium Staff Train Researchers Looking at DDT Levels in Sharks and Rays

January 31, 2024

Aquarium of the Pacific’s veterinarian Dr. Lance Adams and other Aquarium staff members helped train researchers from California State University, Long Beach’s Shark Lab to safely perform liver biopsies in sharks and rays from the Southern California Bight to check for exposure to DDT. The training involved learning how to safely anesthetize the sharks and rays to tag and collect the samples. These researchers are looking to determine if sharks and rays accumulate DDT, and if so, what are those levels. The other part of this three-year study is to track tagged sharks and rays to see where they travel. This will allow the researchers to identify who is exposed to these sharks and rays.

Dichlorodiphenyltrichloroethane or DDT is an insecticide that was banned in the United States in 1972. In March 2023 it was discovered that the DDT was not degrading as projected in the numerous barrels which were dumped into the water along the coastline in the Southern California Bight. Rather, the DDT has been spreading along the seafloor. Previous fish studies concerning DDT focused on commercial fish species, so this active study will help begin to paint a picture for non-commercial fish species.