Oil and Gas Exposure Issues and Health Studies

Transcription

1 Oil and Gas Exposure Issues and Health Studies Mike Van Dyke, Ph.D., CIH Branch Chief Environmental Epidemiology, Occupational Health, and Toxicology

2 Outline How are people exposed? What are the exposures? What do the studies say? Where are we going next?

3 How are people exposed? Well Pad Construction

4 How are people exposed? Drilling

5 How are people exposed? Hydraulic Fracturing (Source: COGCC)

6 How are people exposed? Green Completion (Source: npr.com)

7 How are people exposed? Production

8 How are people exposed? Production

9 How are people exposed? Truck Traffic (Source: Greeley Tribune)

10 Where is the source of air exposures? Venting Leaking tanks/pipes Traffic Combustion equipment Flares

11 What are the potential air exposures? Volatile Organic Compounds (VOCs) Aliphatic hydrocarbons Methane, n-hexane, n-nonane, cyclohexane Aromatic hydrocarbons Benzene, Trimethylbenzenes, Ethylbenzene, Toluene, Xylenes Particulate matter (dust, sand, combustion) Hydrogen sulfide (also sulfur dioxide) Nitrogen oxides (NO x ) Secondary Ozone Carbonyls (formaldehyde, acetaldehyde)

12 What factors influence exposure? Equipment/methods used Length of emission Distance to receptor Topography Meteorology

13 What do we know about health Methane effects? No health effects from low level exposures Particulate matter Increases in respiratory and cardiovascular morbidity Ozone Increases in respiratory morbidity

14 What types of studies have Exposure studies Risk assessments been done? Epidemiology studies using state-based data or administrative data sets

15 Exposure Studies: General Findings Consistent evidence for increasing ozone levels on a regional scale Low levels of many VOCs (ppb) Typically higher than non-impacted rural areas Typically lower than or similar to urban areas Typically lower than would be expected in a normal indoor residential environment With few exceptions, below EPA reference concentrations for health effects Higher, closer to the well Higher, during development phases (old technology) Lower, using green completion technologies Lack of data to assess short-term or peak exposures

16 Risk Assessments: General Findings CDPHE: Garfield County Studies ( ) Lifetime cancer risks slightly above the high-end of EPA s acceptable cancer risk range Low increased risk of developing non-cancer health effects (e.g., respiratory, immunological, and nervous system effects) Cancer and non-cancer risks decrease over time from due to decreasing emissions McKenzie et. al 2012 Lifetime cancer risks within EPA s acceptable cancer risk range Potential for shorter term neurological and respiratory effects for those living in close proximity

17 Risk Assessment Advantages Standardized methodology Only need air monitoring data Typically conservative Disadvantages Results only as good as air monitoring data Theoretical health effects Many chemicals do not have reference values to calculate risk Methods do not account well for complex mixtures

18 Epidemiology Studies: McKenzie et. al 2014 (Colorado) General Findings Higher than expected odds of congenital heart defects and neural tube defects for those living in highest well density areas Jemielita et. al 2015 (Pennsylvania) Cardiology and neurology hospitalizations higher in areas with increased well density Casey et. al 2015 (Pennsylvania) Increased risk of pre-term birth with increase oil and gas activity Stacy et. al 2015 (Pennsylvania) Decreased birth weight and increased small for gestational age in group with highest well density Universal limitations: Surrogate exposure data, Limited or no data on confounders such as socioeconomic status, smoking status, time at residence, etc.

19 Epidemiology Studies Advantages Documented health effects Disadvantages Findings dependent on quality of exposure data Adjustment for confounders sometimes negates initial findings Studies need to be replicated

20 Other Issues You May Hear Endocrine disruptors Limited scientific ability to adequately assess this issue Exposure from contaminated water Data suggest this is a very infrequent occurrence

21 What do we know? Exposure studies Complex mix of low concentration volatile organic compounds Limited data on close-proximity exposures Risk assessments Suggest slightly elevated cancer risk Possibility for respiratory/neurological effects from shorter exposures for those closer and exposed during development activities (using old technology) Epidemiology Studies Very limited (screening level) epidemiology evidence pointing to the possibility for: Increased risk of certain birth defects or birth outcomes (pre-term birth and low birth weight) Increased hospitalizations for respiratory and neurological outcomes

22 Where are we going? New emission regulations (2013) Better exposure data (CSU Study) New risk assessment studies Better registry-based epidemiological studies Collaboration with other states Best practices Shared experiences New health information and response program Systematic collection and analysis of health reports

23 New Risk Assessment (Pending Approval) Emission data from CSU study Calculate health risk By distance By operation Directly attributable to oil and gas activities Early 2018 completion

24 Oil and Gas Information and Response Program New CDPHE program launched 10/15 Statewide hotline for oil and gas health concerns Staffed by health professionals Collect and analyze data on all health concerns Provide a clearinghouse of health information for citizens

25 Oil & Gas Health Information and Response Program Individuals can notify us of a health concern: Call the program hotline at OR Fill out a form on our website at Colorado.gov/OGhealth Staff: Program Physician: Daniel Vigil, MD, MPH Program Toxicologist: Tami McMullin, PhD Program CDPHE_oghealth@state.co.us

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