DES MOINES - A House Democrat specializing in environmental issues Wednesday punched holes in the credibility of the book that five GOP representatives distributed which questions the role human activity plays in global warming.

Rep. Donovan Olson, D-Boone, took aim at authors S. Fred Singer and Dennis T. Avery, who penned the book "Unstoppable Global Warming: Every 1,500 years."

A group of Republican lawmakers recently distributed copies to their peers along with a letter questioning the scientific community's consensus that human activity is the primary cause of global warming.

"I would suggest that folks that received this book do the same thing that I'm going to do with this book: Put it in a recycle bin," Olson said.

Olson, the chair of the House Environmental Protection Committee, noted that Singer has ties to the oil industry and has previously questioned the health effects of second-hand smoke.

And Avery, according to a New York Times report, is a food policy scientist who wants organic food to go away, claiming that it is more dangerous to eat than food produced using chemical pesticides, Olson said.

In response, state Rep. Ralph Watts, R-Adel, decried Orson's attack on the authors' credibility. Watts, one of the GOP lawmakers who distributed the book, said he "dissected" the paperback and that it doesn't contain merely opinion.

"The tactic to attack the messenger is not a new one," Watts said.

CAUCUS TIME OFF -- Democratic presidential candidate Hillary Clinton slammed the Iowa caucuses for disenfranchising people who couldn't attend because they work in the evening.

Sen. Herman Quirmbach, D-Ames, is seeking to change that. He's behind legislation that would allow workers to take up to three hours unpaid leave to attend the presidential caucuses. A limited number of essential emergency service personnel would not be covered.

"We want to make sure that the caucuses are accessible to everybody. I think that's a legitimate criticism that's been made," Quirmbach said.

Ensuring more people can attend the caucuses helps make Iowa's case that its caucuses should remain first in the nation, he believes.

"After all the terrific turnout and all the hard work everybody put in, I think we sure have demonstrated to the country that we have earned our first spot in the nation, but we need to do the best we can to make it even better," Quirmbach said.

LYKAM HONORED -- A law enforcement group Wednesday honored state Rep. Jim Lykam, D-Davenport, for his work on public safety issues.

Lykam, who serves as chairman of the House Public Safety Committee, received the legislative leadership award from the Iowa Association of Chiefs of Police & Peace Officers.

Lykam served a key role in creating legislation to limit the sale of medications containing pseudoephedrine, an ingredient in cold remedies that can be used to make the illegal drug methamphetamine.

Frank Severino, a lobbyist for the association, praised Lykam's vision on public safety issues.

"He does his homework and thinks through every detail on legislation that affects real people, but most of all, he is genuine to the core," Severino said in a written statement.