Superfund Research Program

June 2024

Paper of the Month or Year

Scientists at the University of Arizona SRP Center examined the effects of arsenic, cadmium, ferrihydrite, and pepsin, an enzyme responsible for protein digestion. Scientists used a simulated gastrointestinal (GI) tract to measure bioaccessibility, or the amount of toxic metals that could be released during digestion and absorbed into the blood stream.

Their results showed that cadmium bioaccessibility increased when arsenic was present. Arsenic bioaccessibility decreased with the addition of cadmium, but the arsenic present was transformed into a more toxic form. Both metals formed complexes with ferrihydrite, which promoted the release of cadmium but inhibited the release of arsenic. Pepsin formed soluble complexes with both metals, increasing their bioaccessibility.

To learn more, see the NIEHS Environmental Factor Papers of the Month.