WATCH:  GOP Senator Rob Portman laughs in voter's face after she asks him to stop taking money from Big Oil
Republican Senator Rob Portman riding in a golf cart at the Ohio State Fair in Columbus.

Senator Rob Portman (R-OH) laughed in a woman's face on Friday when she asked him to stop accepting political contributions from the fossil fuel industry, the Huffington Post reports.

In video posted to Facebook by the group Indivisible Columbus District 3, a mother confronted Sen. Portman about his support for a bill activists worry will benefit polluters.

“Well then could you stop taking money from the fossil fuel industry?" the mother asked.

"Because then I’d feel more comfortable that you’re doing it for the right reasons," she explained.

Senator Portman simply laughed, refused to answer and drove off in a golf cart.

The initial bill in question, that the mother worried would harm her children, is the Regulatory Accountability Act. The activists who confronted Sen. Portman have branded it a "license to pollute" bill that "could harm us by rigging the system for corporations, polluters, and big pharmaceutical companies responsible for the opioid crisis."

When Portman introduced the bill in April, the Environmental Working Group identified $3.3 million that Portman received in 2016 -- nearly half of all his donations -- came from people and organizations backing the bill.