This document summarizes and compares three health studies on shale gas development and human health outcomes. The studies found some associations between shale gas activity and increased hospitalization rates, higher reports of dermal and upper respiratory conditions, and certain birth defects. However, the studies have limitations like lack of direct exposure measures, potential reporting biases, and inability to rule out other contributing factors. Overall, more research is still needed to better understand potential health impacts.

1. Shale Gas Health Research: A
Review
STEVEN H. LAMM, MD DTPH
HAMID FERDOSI, MPHc
Center for Epidemiology and
Environmental Health (CEOH)
3401 38th
Street, NW Washington, DC 20016
202/333-2364 Steve@CEOH.com

2. Population

3. Is adverse health significantly associated
with fracking exposure?
•What health outcome?
•What exposure?
•What do we mean by association?

4. Health Outcome
Adult
•Death
•Severe disease (cancer, heart disease)
•Hospitalization
•Health Symptoms
•Well-being
Newborn
•Low birth weight
•Prematurity
•Small for Gestational Age
•Birth defect
•Neurodevelopment

5. Exposure
•Inhalation or Ingestion
•Specific Chemical or Mixture
•Process

6. Association
•Biomarker (Blood or urine level)
•Location – county, zip code, address

7. Three Health Studies
Jemielita et. al, 2015
Hospitalizations in three counties in NE Pennsylvania
Rabinowitz et al. , 2015
Health Symptom Survey in Washington County, PA
McKenzie et al. , 2014
Birth Outcome in rural and small town Colorado

8. Unconventional Gas and Oil Drilling (UGOD)
and Hospital Utilization Rates
Study Population
• Residents of three NE Pennsylvania counties (Bradford
and Susquehanna vs. Wayne).
Health Outcome Instrument
• In-state Hospital discharge (2007-2011) data purchased
Jemielita T, Gerton GL, Neidell M, Chillrud S, Yan B, Stute M, et al. (2015) Unconventional Gas and Oil Drilling Is
Associated with Increased Hospital Utilization Rates. PLoS ONE 10(7): e0131093.

9. Three County Map

10. UGOD and Hospitalizations
Exposure Measure
• 67 zip codes with well counts (wells/zip) and well density
(wells/km2
) per year.
Results
• Risk Ratio (RR)
• Analysis based on discharge codes [DRG and ICD-9]
• Positive association – Cardiology, Neurology
• Negative association – Gynecology, Orthopedics

11. UGOD and Hospitalizations
Strengths
• Large population based
study (157,526)
• Reference county had no
wells
• 92,805 hospitalization
records (2007-2011)
Limitations
• Border counties without
cross-border (NY)
hospitalizations.
• Not adjusted for hospital.
• Annual data not
independent.

12. Household Symptom Survey in
Washington County, Pennsylvania
Study population
• 492 adults in 180 randomly-selected households with
ground-fed wells in NGW area of Washington County, PA
(Summer 2012)
Health Outcome Instrument
• Health symptom survey (Interview)
Rabinowitz PM, Slizovskiy IB, Lamers V, Trufan SJ, Holford TR, Dziura JD, Peduzzi PN, Kane MJ, Reif JS,
Weiss TR, Stowe MH. 2015. Proximity to natural gas wells and reported health status: results of a household
survey in Washington County, Pennsylvania. Environ Health Perspect 123:21–26.

13. Household Symptom Survey
Exposure Measure
•Kilometers from nearest Natural Gas Well –
< 1 km, 1-2 km, with > 2 km as reference group
Results
•Adjusted Odds Ratios (OR)
•Positive association – Dermal (4.1); Upper Resp (3.1)
•No association - Lower Resp; Cardiac; GI; Neuro

14. Household Symptom Survey
Strengths
• Random selection of
sampling points
• Community cohort
without stated exposure
knowledge.
Limitations
• Self-reported symptoms
• No adjustment for multiple
comparisons (Bonferroni
Correction)
• Analyzed by person rather
than by household or adult.
• Does not distinguish
between shallow and deep,
old, etc.

15. Birth Outcomes in Rural Colorado
Study Population
• Geocoded maternal addresses in rural and small town
(<50,000) Colorado in 57 counties.
Health Outcome Instrument
• Colorado Responds to Children with Special Needs (CRCSN)
registry matched to 1996-2009 live birth certificates (N =
124,842).
• Birth defects – Oral clefts, Neural tube defects, Congenital
heart defects.
• Birth characteristics – Preterm, term (> 37 wks) Low birth
weight, term mean birth weight
McKenzie LM, Guo R, Witter RZ, Savitz DA, Newman LS, Adgate JL. 2014. Birth outcomes and maternal
residential proximity to natural gas development in rural Colorado. Environ Health Perspect 122:412–417.

16. Birth Outcomes in Rural Colorado
Exposure Measure
• Inverse distance weighted well counts within 10 miles
radius and then in tertiles above zero.
Results
• Adjusted Odds Ratio (OR)
• Positive association – Congenital heart defects (VSD,
Pulm, Tricusp), Neural tube defects
• No association – Oral clefts
• Negative association – Preterm, Term LBW,

17. Birth Outcomes in Rural Colorado
Strengths
• Large cohort study
(124842 births)
• Individual addresses
Limitations
•Assumed 1st
trimester
exposure
•Not restricted to isolated
(non-syndromic)
malformations.
•Not adjusted for SES,
health, nutrition, prenatal
care, pregnancy
complications

18. Comparison
Jemielita Rabinowitz McKenzie
Exposure Wells/zip code Nearest well 10
mile count
or Wells/Km2
(Inverse
distance)
Health Hospital Record Interview State
Health Rec.

19. Comparison
Jemielita Rabinowitz McKenzie
Yes Cardiac; Neuro Derm; URI BD –
CHD, NTD
No/? Gyn; Ortho Cardiac; Neuro;
Prem; Term LBW Derm; Pulm GI; LRI
BD - OC

20. Concerns
•None of these studies have exposure measures.
•All of these studies are still hypothesis-generating.
•Do these approach the questions that the public is
asking?
•How do you show a negative?