Arnold Schwarzenegger tweets to Pruitt about water contamination

"I'm a simple guy so I have a simple remedy when people like Pruitt ignore or hide pollution: if you don't have a problem with Americans drinking contaminated drinking water, drink it yourself until you tap out or resign," Schwarzenegger wrote.

The actor and former Republican governor of California included the article by Politico in his Wednesday tweet.

Citing newly disclosed emails, which have been obtained by CNN, Politico reported earlier this week that the study by the Health and Human Services' Agency for Toxic Substances and Disease Registry, which would have given additional warnings about polluted US water supplies, raised concerns within the administration, with one aide warning it would cause a "public relations nightmare."

This is the latest in a string of controversies in which Pruitt has become embroiled. On Wednesday, the embattled administrator appeared on Capitol Hill to defend himself against criticisms of his alleged ethical transgressions.

CNN has reported that Pruitt is the focus of nearly a dozen probes by ethics watchdogs, federal auditors and congressional committees looking into his actions as head of the agency.

The inquiries are looking into his travel expenses, personal security and various ethical concerns, including Pruitt's lease of a condominium at below-market rate from a couple with energy lobby ties.