Weak methodologies and a lack of actual measurements of any potential pathways skew certain outcomes in the recently released University of Pittsburgh health and environment studies.

Certain media outlets, unfortunately, chose to sensationalize the so-called “findings” with headlines aimed at generating clicks, and not fully examining the actual studies, their shortcomings or factoring years of contrary independent research.

Despite what the media suggested, the reports did not demonstrate any causation from unconventional shale development to any of the health risks studied. Rather, researchers made proximal associations using skewed measurements and didn’t even attempt to account for key environmental and other factors that have demonstrable impacts on health.

  • The studies relied on a very limited proximity metric which doesn’t identify any exposure pathways, assumes constant emissions and ignores critical factors like weather, work, air dispersion, lifestyle choices and other sources.

Why did these researchers – who received nearly $3 million in taxpayer funding – simply use statistical models? Why didn’t they ever visit a shale gas site, and refuse opportunities to do so, in order to actually understand the development process and/or conduct actual air and water quality testing?

Despite flaw in design metrics and the limitation of certain information they utilized importantly these studies confirmed no association to adverse birth impacts, Ewing’s sarcoma and other bone cancers, as well. That said, and given the narrative being driven by those who will never see it otherwise, the following points need to be made about the various studies.

CHILDHOOD CANCER STUDY

“No evidence was found to support an association between exposures to [natural gas] activities and other environmental factors and the risk of leukemia, [central nervous system] tumors, and malignant bone tumors, including [Ewing’s Family of Tumors],” Pitt researchers acknowledge.

Lymphoma correlation was extremely low and underscored the limited methodologies employed.

  • Utilizing proximity measurements to determine exposure is a weak approach because it doesn’t identify or establish any exposure pathway between natural gas development and health outcomes. Furthermore, exposure to lymphoma was calculated by analyzing maternal addresses on birth certificates and checking if natural gas development was within a 10-mile radius at the time of birth.
    • Residence changes, even within the county, were not factored, nor was the transient nature of individuals (i.e. travel and situs every day, whether to work or school, for example).
    • Smoking status during pregnancy, prenatal care, and other important factors were not excluded during the study.
    • Importantly, none of the detailed exposure survey data, such as family history of cancer, exposure to radiation, smoking history, indoor and outdoor environmental exposures, etc. were considered in the analysis.
  • Context is key: While the relative risk comparing cases to controls increased from the national average, the estimated risk of lymphoma remained very low – 0.006% – 0.0084% – in the 8-county area.
  • Association weakens in more rigorous survey data: Researchers saw a stronger association in the birth record study portion vs. the human survey portion causing them to downgrade the evidence of lymphoma ties from “strong” to “moderate” throughout the study. This indicates either survey-based results (in which Pitt asked participants to complete a health questionnaire) were not statistically significant and/or they lacked the same relationship that the birth record results presented in the report.
  • Unknown data muddies correlation waters: Lymphoma is commonly diagnosed between the ages of 15 and 19. Since information is not presented on when the lymphoma cases occurred and at what age they were diagnosed, it is unknown how much overlap there was between their exposure period and years of unconventional production activity in southwestern PA.

ASTHMA STUDY

Western Pennsylvania asthma cases drop as natural gas production increases despite study’s supposed exacerbation finding.

  • Production rises, asthma falls: Asthma cases in the eight-county study region have fallen significantly as natural gas production has risen, which is opposite of the study’s primary finding associating asthma exacerbation with gas production. In fact, data shows that from 2014 to 2020, severe asthma cases declined by nearly 50% – even as production in the eight-county study region increased by nearly 200%.

  • No link to pad preparation, drilling, or hydraulic fracturing phases: Asthma exacerbations were not linked with proximity to wells in pad preparation, drilling or hydraulic fracturing phases, regardless of how close wells were to homes or the number of wells nearby.
  • The only association claimed was to the production phase, when little to no activity occurs on the pad and emissions are minimal, at best. Again, Pitt’s own research shows a decline in severe asthma despite significant production increases.
  • Improving regional air quality: Across the study period, air quality in the Western Pennsylvania region has generally improved, with particulate matter – a known asthma trigger – notably declining in the eight-county study area to well below national air quality standards (NAAQS), according to U.S. EPA data.
    • According to the Asthma and Allergy Foundation of America’s “Most Challenging Places to Live with Asthma”, no region (including Pittsburgh) with natural gas development falls in the top 20, but Philadelphia, Allentown, and Harrisburg each do.
  • No other asthma triggers considered: The researchers were limited to the information found in medical records. Meaning that while smoking status was accounted for, a child’s exposure to secondhand smoke, for example, was not. Other known asthma triggers ignored, as identified by the CDC, include indoor and outdoor air pollutants, like dust mites, mold, and pests. This leaves a huge gap in potential other external factors that are known to exacerbate asthma.
    • It’s also key to note rural populations and lower income levels are highly associated with asthma development and poorer management due to generally decreased healthcare access and utilization. These considerations were noticeably missing during Pitt’s data gathering phase, as medical records rarely include access to healthcare or socioeconomic indicators.
  • What constitutes ‘severe’?: The standard in medical studies is to categorize asthma cases as mild, moderate, and severe. Pitt’s study breaks from medical research norms, however, as all three levels were labeled as ‘severe asthma’ without explanation. The American Thoracic Society (ATS) estimates between 5-10% of asthmatics have a ‘severe’ case, yet Pitt’s study estimated this percentage around 40% – which conflicts with common medical understandings of the disease.
  • Proximity does not = exposure: Rather than taking air quality samples onsite or observing emissions data, the model presumes that living near a well equates to having constant, harmful exposures from it. This model ignores distance, weather patterns, dispersion, as well as other potential sources like highways, agriculture, industry, etc.

BIRTH OUTCOMES STUDY

Study finds birthweights remain in normal healthy range, no association to other adverse birth outcomes.

  • Birthweights in normal range, fluctuations “pose little health risks”: Of the three health outcomes studied, only one was found to be consistently associated with natural gas activity. But as the researchers point out, the ~1 ounce difference “poses little health risks.”
    • Context around these findings is very important. The average birthweight in the cohort was 3400 grams, which is within the national average of 2400-4000 grams. The greatest reduction in birthweight associated with well exposure was ~27 grams – or 0.8% below the average – yet still well within healthy birthweight ranges.
  • Critical health information overlooked: This was another records-based study, meaning pertinent information on both the infant and mother were limited to what is captured on birth certificates. Importantly, the methodology ignores time spent away from the home address and exposure to other nearby point and mobile sources of pollution. It also assumes the home address listed on the birth certificate was the same throughout pregnancy.
    • Common causes of low birthweight or preterm babies, such as smoking or consuming alcohol during pregnancy, are often not reported on birth certificates. As a New York Times headline reads, “Smoking for Two, and Lying About It”, about 23% of pregnant smokers reported otherwise on health records.
    • Fine particulate matter was presented as a causal exposure pathway in the study, but researchers provided no evidence to support this claim. As noted, EPA records indicate particulate matter concentrations actually declined in the 8-county area during the study period.
    • Interestingly, the odds of preterm birth were actually higher for those living with no natural gas activity near the mother’s residence during pregnancy.
  • Proximity-based model lacks exposure pathway evidence: As with the limitations of the asthma and cancer-focused studies, the methodology used was proximity-based, which lacks evidence of any exposure pathway and ignores key environmental factors.

These significant limitations have been largely ignored in news reporting and call into question the studies’ conclusions. As an industry made up of Pennsylvanians, who live in these communities, our top commitment has always been and will always be protecting health, safety and our environment.