A new study published in Frontiers in Marine Science has found that sharks are vulnerable to dental breakdown due to increased acid content in the world’s oceans. The researchers, led by Maximilian Baum from Heinrich Heine University Düsseldorf, analyzed 600 teeth shed by blacktip reef sharks and placed them in two different tanks with pH levels of 8.1 (current ocean) and 7.3 (projected 2300). After eight weeks, the team found that the teeth in the more acidic tank had deteriorated around 50% more than the ones in the other tank.
The study’s results showed visible surface damage, cracks, and holes on the teeth in the acidic environment. The researchers also found that the teeth became structurally more brittle and prone to breaking. This suggests that sharks’ dental hardware is not resistant enough to ocean acidification.
The findings are particularly concerning for species like blacktip reef sharks, which need to swim with their mouths permanently open to breathe, exposing their teeth to acidic water. The researchers warn that moderate drops in pH could affect sensitive species and have cumulative impacts over time.
While the study used discarded teeth of non-living mineralized tissue, the team acknowledges that living sharks may be able to remineralize or replace damaged teeth faster, but at a higher energy cost in acidified waters. Ultimately, the researchers conclude that ocean acidification is not only affecting small and tiny creatures but also large marine predators like sharks.
Source: https://nypost.com/2025/08/27/science/sharks-teeth-are-corroding-due-to-acidic-waters-study