Second Highest Rate in the Nation: Pennsylvania Mesothelioma by the Numbers

Pennsylvania ranks second only to Wisconsin (1.24 per 100,000) for per capita mesothelioma, with a rate of 1.22 per 100,000 residents. The national average is 0.6. That means Pennsylvanians develop mesothelioma at roughly twice the rate of the typical American.

The reason is industrial. Pennsylvania’s steel mills, shipyards, and manufacturing plants used asbestos across every stage of production. From Bethlehem Steel in the Lehigh Valley to the Philadelphia Navy Yard on the Delaware River, workers inhaled asbestos fibers as part of their daily routine for decades. Those exposures are producing diagnoses now, 30 to 50 years later.

State Rankings

For a full comparison of all 50 states, see our mesothelioma rates by state rankings.

County-Level Data

The geographic distribution reveals two distinct clusters. In southeastern Pennsylvania, Delaware and Montgomery counties near Philadelphia reflect the shipbuilding, refining, and manufacturing industries that lined the Delaware River. In western Pennsylvania, Butler, Beaver, and Westmoreland counties surround Pittsburgh, where steel production and heavy industry drove exposure for generations.

Where Exposure Happened

Pennsylvania’s asbestos burden traces to four primary sectors.

Steel Mills in Bethlehem and Pittsburgh

Bethlehem Steel’s Lehigh Valley complex was one of the largest steel operations in the world. The company’s furnaces, rolling mills, and fabrication shops all used asbestos insulation, fireproofing, and gaskets. Pittsburgh’s steel mills along the Monongahela and Ohio rivers created a parallel corridor of exposure that extended into Ohio’s Cleveland steel belt, Indiana’s Gary mills, and Chicago’s Southeast Side. Steelworkers, maintenance crews, and construction tradespeople at these facilities inhaled asbestos throughout their careers.

The Philadelphia Navy Yard

The Philadelphia Navy Yard was the largest naval shipbuilding facility on the East Coast. From World War II through the Vietnam era, thousands of workers built and repaired warships in conditions where asbestos was embedded in nearly every system. Pipe insulation, boiler lagging, fireproofing, and gaskets all contained asbestos. Below-deck work in enclosed compartments created particularly concentrated exposure. Workers at the Philadelphia yard shared the same hazards as those at the Brooklyn Navy Yard in New York, Jacksonville’s naval shipyards in Florida, and the Savannah shipyards in Georgia.

Statewide Manufacturing Plants

Across Pennsylvania, manufacturing plants used asbestos in machinery insulation, gaskets, brake systems, and fireproofing. Industries from auto parts to electrical equipment to cement production all relied on asbestos-containing materials.

Pre-1980 Construction Trades

Pre-1980 commercial and public buildings throughout Pennsylvania were constructed with asbestos-containing materials. Insulation, floor tiles, roofing, and fireproofing all contained asbestos. Construction tradespeople, especially insulators, pipefitters, and electricians, faced daily exposure.

Who Is Most at Risk

• Steelworkers at Bethlehem Steel, Pittsburgh mills, and smaller operations statewide
• Shipyard workers at the Philadelphia Navy Yard and Delaware River facilities
• Pipefitters and insulators in industrial and commercial construction
• Boilermakers at power plants and industrial facilities
• Construction tradespeople working in pre-1980 buildings
• Maintenance crews at manufacturing plants, refineries, and power stations

Of the approximately 6,000 mesothelioma cases studied in Pennsylvania, 85% were pleural mesothelioma, which originates in the lining of the lungs and is most strongly associated with inhaling asbestos fibers.

Legal Options for Pennsylvania Workers

For an overview of all current treatment options, see the 2026 mesothelioma treatment landscape. Pennsylvania’s asbestos trust fund claims are relevant for workers across the steel, shipbuilding, and manufacturing industries. The companies that manufactured asbestos-containing products used in these facilities have established bankruptcy trusts that continue to accept claims.

Verdicts and settlements in Pennsylvania reflect the state’s industrial profile, with significant outcomes tied to steel mill, shipyard, and construction exposure.