Scientists investigate biological tolerance for arsenic

By Peter Kent

What you don’t know could kill you. Take arsenic, for example. Even nonfatal levels of the deadly poison can make people sick, and the chemical has been linked to brain development problems in children and cancers in adults.

That’s why the killifish has taken an important role in a Clemson biology study. A small, hardy and prolific fish, the killifish is serving as a scientific model for the effects of arsenic on early stages of growth.

Clemson biologist Lisa Bain is conducting the research, funded by the Clemson Experiment Station. And her research indicates that even low percentages of the poison harm killifish.

"At fairly low levels, arsenic appears to cause reduced muscle fiber density in young killifish," Bain said. "Born with fewer numbers of fast-twitch muscle fibers, they are weaker and unable to swim fast, which affects their ability to capture food and escape becoming prey."

That weakened muscle condition can be passed from one generation to the next, she said.

Her study results suggest that current levels of arsenic tolerance set by the government may need to change, Bain said. That’s especially important to South Carolina, which is one of eight states that the U.S. Environmental Protection Agency says have higher-than-average arsenic concentrations in the water.

"The levels currently set by government should be reviewed and research supports revising them to lower levels in drinking water," Bain said.

Learn more about work at the Clemson Experiment Station: