By Justin Heinze & Kara Seymour:

Toxic waste is an invisible problem across much of the United States, including Pennsylvania. Toxic chemicals plague hundreds of municipalities in the Keystone State, and it's not just in the places you would expect, with industrial refineries in sight.

Thanks to the Right-to-Know Network website, rtknet.org, the public now has a detailed look into exactly where toxic pollution is the worst, and exactly what that pollution is comprised of. In Pennsylvania, 97.2 million pounds of these chemicals were released by 1,168 facilities required to report under the so-called "right-to-know law" in 2013, the most recent year for which full data is available.

The Right To Know Network website, or RTKnet.org, keeps a detailed Toxics Release Inventory, which provides details about the releases and transfers of all toxic chemicals, including manufacturing, waste handling, mining, and electricity generation. Below is a complete list of all 385 Pennsylvania municipalities that have at least one pound of "on-site" releases of toxic chemicals. Thirteen different locales have over one million pounds of releases, including Philadelphia, which placed 12th overall.

Nine Bucks County Towns made the list.

According to RTKnet.org, these nine towns are among the state's most toxic:

Bristol - #34

Warminster - #104

Quakertown – #134

Morrisville - #158

Fairless hills - #171

Southampton – #173

Bensalem – #239

Levittown - #356

Perkasie - #381 Zinc was the most common toxin released, accounting for 29 million pounds, as much as the next three chemcials combined. Horsehead Holding Corporation, a chemical manufacturer based in Pittsburgh, led the way among all businesses with 19 million pounds of pollutants.