An energy company executive's sip of fracking fluid at an industry conference this month has been called a demonstration by some and a stunt by others, but it's bringing attention to new recipes for hydraulic fracturing fluids that in the past have contained chemicals used for antifreeze or bleaching hair.

In a speech at the conference presented by the Colorado Oil and Gas Association, Halliburton Co. CEO Dave Lesar talked about addressing public concerns about hydraulic fracturing, which extracts natural gas by blasting a mix of water, chemicals and sand underground.

He raised a container of Halliburton's new fracking fluid made from materials sourced from the food industry, then called a fellow executive to demonstrate how safe it was by drinking it, two attendees said.

What the person drank apparently was Clean Stim, which when Halliburton announced it in November was undergoing field trials. A Halliburton spokeswoman didn't respond to a question asking how that executive is doing now or who he is. She referred a reporter to a Web page on CleanStim. The Houston company, with operations in about 80 countries, has said the product shouldn't be considered edible.