PITTSBURGH -- Citizens groups and nonprofits around the nation are asking questions about environmental and health impacts of natural gas hydraulic fracturing, or fracking, and Pennsylvania charities are funding much of the debate, here and in other states.

Foundations from Philadelphia to Pittsburgh have provided more than $19 million for gas-drilling-related grants since 2009, according to an Associated Press review of charity data. The money has paid for scientific studies, films, radio programs, websites and even trout fishing groups that monitor water quality.

That's led to expressions of gratitude from those who say state and federal governments aren't doing enough on the issue, but also protests from some in the gas drilling industry, who claim there's bias in the campaigns.

"We are trying to be balanced. We will sacrifice the environment for nothing," said Robert Vagt, president of the Heinz Endowments, a Pittsburgh charity founded in 1941. The foundation, which is not affiliated with the company of the same name, has given more than $12 million to Cornell University, the Clean Air Council, the Foundation for Pennsylvania Watersheds, Duquesne University, the environmental law organization Earthjustice, the Pittsburgh Filmmakers, Trout Unlimited and others.

One scientist said some research wouldn't have happened without the Heinz support.

"Foundation support has been critical as we and others who study water have worked to understand how energy and water resources affect each other in southwestern Pennsylvania," Carnegie Mellon University professor Jeanne VanBriesen wrote in an email.

R. John Dawes, the executive director of the Foundation for Pennsylvania Watersheds, said Heinz funding "has been critical for citizen awareness and citizen input" on the gas-drilling issue.

But the Marcellus Shale Coalition, a leading industry group, criticized what it sees as a "record of bankrolling organizations and institutions opposed to the safe development of job-creating American natural gas."

"As clean-burning natural gas from the Marcellus Shale is creating tens of thousands of jobs, enhancing air quality, providing lower energy costs for consumers and helping to make our region a manufacturing hub once again, it's ironic, if not disingenuous, that the Heinz Endowments claims to be focused on 'solutions to challenges that are national in scope,'" said Steve Forde, a Shale Coalition spokesman.

The recipients of Heinz grants have a wide range of views. Some take no official position or just want better oversight, while others are clearly opposed to drilling.

For example, Earthjustice received a $50,000 Heinz grant to "ensure environmentally sustainable natural gas exploration and production in the Marcellus Shale." But the Earthjustice website calls fracking dangerous and shortsighted and said it's "poisoning our air and water and on its way to jeopardizing the health of millions more Americans," and instead urges investments in renewable energy.

Fracking has made it possible to tap into deep reserves of oil and gas but has also raised concerns about pollution. Large volumes of water, along with sand and hazardous chemicals, are injected underground to break rock apart and free the oil and gas. Contaminated wastewater from the process can leak from faulty well casings into aquifers, but it's often difficult to trace underground sources of pollution. Some studies also have shown air quality problems around gas wells, while others have indicated no problems.

Regulators contend that overall, water and air pollution problems are rare, but environmental groups and some scientists say there hasn't been enough research on those issues. The industry and many federal and state officials say the practice is safe when done properly, and many rules on air pollution and disclosure of the chemicals used in fracking are being strengthened.

Vagt said the Heinz Endowments simply believes that many questions about gas drilling still need answers.

"There are lots of positions being taken with a relative paucity of data. The potential consequences are serious and permanent," he said.

Heinz has also worked with gas drilling companies on projects, such as a study that EQT Co. supported that examines whether it makes environmental and financial sense to convert Pittsburgh's bus fleet to run on natural gas.

Andrew Johnson, a program officer with the William Penn Foundation based in Philadelphia, said that region's drinking water is a prime focus of the more than $2 million in grants they've awarded during the past year.

"The reason we're stepping up is to a large degree the Philadelphia water supply comes from the forested headwaters," Johnson said, adding that campaigns to get more federal oversight of gas drilling have been a priority.

"We've also tended to focus on efforts to encourage U.S. EPA to become more involved, mobilizing people to become actively engaged," he said of the federal Environmental Protection Agency. "It wasn't clear to us that what had been done was sufficient," he said of local and state efforts.

State officials have criticized EPA's involvement with gas drilling issues.

"This organization is welcome to spend its money however it chooses; but the truth is that in Pennsylvania, DEP's strong regulations ensure that drilling is done right," said Katy Gresh, director of the Pennsylvania Department of Environmental Protection's communications office. "EPA oversight has never been necessary for us to make that pledge, and it is not necessary now."

The William Penn Foundation has given money to the Sierra Club, Citizens for Pennsylvania's Future, the Delaware River Basin Commission, the National Resources Defense Council, Trout Unlimited and others. Those groups have a range of opinions on gas drilling, from outright opposition to cautious support.

All the foundations say they're responding to needs that match their core missions, as well as simply helping people who are concerned about gas drilling.