01 November 2012

Roxana Witter, MD, MSPH Colorado School of Public Health Speaks on Comprehending Health Implications of Natural Gas (NG) Development

Roxana Witter, MD, MSPH Colorado School of Public Health, recently spoke at the American Public Health Association Conference October 30, 2012 on the topic:

"Comprehending Health Implications of Natural Gas (NG) Development Through Public Health Research". 

She covered current Public Health Research, Hazards to Public Health, Water Studies, Air Quality, Suspected Effects on Pets and Humans, Climate Change, and Planned Research.
The Climate Change portion is very interesting. Although NG emits less carbon dioxide than coal when burned, methane is an approximately 20x more powerful GHG. When looking at the whole NG Lifecycle, studies suggest that NG methane emissions could lead to more GHG impact than coal. The extent of methane emitted by NG development, production, transmission and end use is an area of active investigation.  

With Roxana's permission to share her presentation's facts on Clean Tech and Green Business News, here are some important highlights referenced from her presentation which we all need to know.

1. Between 2010-2035, there will be a 29% increase in NG production with most of the increase being in shale gas

2. Public Health Research and Literature is in its infancy
• Environment Health Perspectives News, 2011 – Review of water,  air,  regulatory, concerns and lack of health effects studies 
• Finkel, 2011 AJPH Commentary
– Hydraulic Fracturing Chemicals (Known: dangerous; some unknown  and Multiple pathways for exposure)
• Guidotti, 2011Arch Enviro Occ Health Editorial – Scientific uncertainty
– Risk- risk tradeoffs (climate change vs. local environmental degradation)

3. Hazards to Public Health
• Chemical
– Water
– Air • Physical
– Noise
– Traffic • Community
– Population changes
– Physical changes
• Psychosocial
– Stress
• Susceptible subpopulations include children, elderly, fetus, chronic disease, poor

4. Concerns About Water
• Quantity – 1-2 million gallons/drill
– 2-5 million gallons/hydraulic fracture
• Quality – Chemicals
Hydraulic fracturing, drilling, naturally occurring – Contamination of ground water and surface water
• Disposal – Salts, metals, hydrocarbons, radioactivity (NORM)
– Earthquakes

5. Water-recent Studies and Data Pennsylvania 
Osborne, 2011 PNAS, Warner, 2012 PNAS
• Activegasareas
– Methane concentrations in drinking water higher close to gas wells
• Geochemical evidence for natural fractures between shale gas formations and shallow aquifers
– Increased risk for contamination, especially for fugitive gases

6. Water-Recent Studies and Data Pavillion, Wyoming EPA http://www.epa.gov/region8/superfund/wy/pavillion/
Chemicals found in drinking water aquifer
Consistent with NG operations
Organic and inorganic chemicals
NG activities enhanced gas migration to aquifer
Deep source of contamination (wells, fracturing)
– HighpH,salts,petroleum hydrocarbons (BTEX gasoline range organics, trimethylbenzenes) synthetic organic compounds (isopropanol, di&triethylene glycol)
Shallow source of contamination (pits)
– Benzene,xylenes,gasoline range and diesel range organics in shallow ground water
USGS repeated analysis from 2 sites: similar findings

7. Water Contamination
Risk Analysis Rozell, 2012 Risk Analysis
• Probability bounds analysis
• Modeled 5 possible water contamination pathways
– Casing failure, fracture migrations, surface contamination, transportation, disposal
• Wastewater disposal poses highest risk (by several orders of magnitude)

Wastewater Contamination
Balba, 2012 Chemosphere
• High levels of arsenic and selenium in Marcellus shale
• High volume hydraulic fracturing could mobilized these chemicals into wastewater, posing environmental hazard.

8. Air Quality
• Onsite Silica, Diesel exhaust, BTEX, PM, glutaraldehyde
• Near pad – Diesel exhaust, BTEX, PM (PAH, SO4)
• Regional Ozone
• Global Methane
BOLD= Preliminary data of levels
11 sites in AR, CO, ND, PA, TX
116 Personal breathing zone, full shift samples • Exceeded OSHA PEL,
NIOSH REL, ACGIH TLV • 31% w/ levels above what
respirator could handle

Local Air Quality (near pad) Mckenzie, 2012 Sci Total Environ
Health Risk Assessment
EPA screening assumptions
24 samples from near well pad
163 samples from ambient air in NG area 
Risk of sub-chronic and chronic non-
cancer health effects elevated
Excess cancer risk slightly higher

Contributing Chemicals Aliphatic hydrocarbons
• Trimethylbenzenes
• Benzene
• Xylene
1,3 Butadiene
• Ethylbenzene

9. Suspected Effects on Pets, Livestock, Humans
Bamberger, 2012 New Solutions
Case series (24) • Animal owners in six states (CO,
LA, NY, OH, PA, TX) • Water exposures
Well casing failures, blowouts, wastewater dumping and leakage, fracturing/drilling chemical spills
Air exposures Flares, compressor station
Animal health effects Reproduction, milk production, poor
condition (skin, GI, urological,
respiratory, neurological), death
Human (owner) effects Respiratory, neurological, skin, GI

10. Global Climate Change & NG Lifecycle Topic of much debate and uncertainty
NG Combustion
• Less CO2 emissions than coal
– Also less mercury into the atmosphere

NG Whole lifecycle
• Methane 20x stronger GHG
• Methane leakage – Extraction – Processing – Distribution – Inefficient engines

Lifecycle GHG Emissions Based on emission estimates
Howarth, 2011 Climatic Change – Shale gas > conventional gas> coal
Weber, 2012 Environ Sci Technol – Shale gas = conventional gas < coal
Burnham 2012 Environ. Sci Technol – Shale gas = conventional gas < coal
Alvarez, 2012 PNAS – NG < coal (electricity generation);
– NG > gasoline, diesel (transportation)
Due to inefficient engines and leaky distribution system
Measurements of GHG in Atmosphere Greater than Estimates
• Katzenstein, et al 2003
 Methane and other hydrocarbon emissions from oil and gas fields underestimated
• Petron,2012JGeophysicalAtmospheres
Methane from Natural Gas activities in Colorado likely underestimated by a factor of 2

11. Planned Research
University of Colorado Air and water quality, social science, human health, information
technology, outreach and education
Colorado State University Assess air emissions and dispersion of drilling, hydraulic fracturing,
flowback in Garfield County, CO – Data released in 2015
Geisinger Health System Pennsylvania integrated health care delivery system – Longitudinal dataset of health outcomes for researchers to determine
NG related health outcomes – Health, environmental, community, occupational data

Reference Article:
During the 2012 Wall Street Journal ECOnomics conference, I featured Speakers including Riverkeeper's Paul Gallay who discussed 'Fracking'.