Adverse health risks increase with proximity to fracking facilities

Unconventional oil and gas development is rapidly encroaching on heavily populated neighborhoods, posing potential risks to human health

Dr. Lisa McKenzie presents results from a human health risk assessment that characterized prenatal through adult health risks from exposure to non-methane hydrocarbons in Colorado populations living near oil and gas development. The study found that both air pollutant concentrations and health risks increased with proximity to oil and gas facilities.

Lisa McKenzie, PhD MPH,is an Assistant Research Professor at the Colorado School of Public Health on the University of Colorado Denver’s Anschutz Medical Campus. Her expertise is in exposure assessment and environmental epidemiology, and human health risk assessment. Dr. McKenzie’s research has contributed to the understanding of how air pollutants and other exposures resulting from the unconventional development of petroleum resources may affect the public’s health.

Reference.  Image blogs.sierraclub.

Air pollution may increase dementia risk by 40 percent, London study finds

Are noise and air pollution related to the incidence of dementia ?
A cohort study in London, England, 2018

Air pollution may increase the chance of developing dementia, a study has suggested, in fresh evidence that the health of people of all ages is at risk from breathing dirty air, TheGuardian reports.


To investigate whether the incidence of dementia is related to residential levels of air and noise pollution in London.

Retrospective cohort study using primary care data.

75 Greater London practices.

130 978 adults aged 50–79 years registered with their general practices on 1 January 2005, with no recorded history of dementia or care home residence.

Primary and secondary outcome measures
A first recorded diagnosis of dementia and, where specified, subgroups of Alzheimer’s disease and vascular dementia during 2005–2013. The average annual concentrations during 2004 of nitrogen dioxide (NO2), particulate matter with a median aerodynamic diameter ≤2.5 µm (PM2.5) and ozone (O3) were estimated at 20×20 m resolution from dispersion models. Traffic intensity, distance from major road and night-time noise levels (Lnight) were estimated at the postcode level. All exposure measures were linked anonymously to clinical data via residential postcode. HRs from Cox models were adjusted for age, sex, ethnicity, smoking and body mass index, with further adjustments explored for area deprivation and comorbidity.

2181 subjects (1.7%) received an incident diagnosis of dementia (39% mentioning Alzheimer’s disease, 29% vascular dementia). There was a positive exposure response relationship between dementia and all measures of air pollution except O3, which was not readily explained by further adjustment. Adults living in areas with the highest fifth of NO2 concentration (>41.5 µg/m3) versus the lowest fifth (<31.9 µg/m3) were at a higher risk of dementia (HR=1.40, 95% CI 1.12 to 1.74). Increases in dementia risk were also observed with PM2.5, PM2.5 specifically from primary traffic sources only and Lnight, but only NO2 and PM2.5 remained statistically significant in multipollutant models. Associations were more consistent for Alzheimer’s disease than vascular dementia.

We have found evidence of a positive association between residential levels of air pollution across London and being diagnosed with dementia, which is unexplained by known confounding factors.

Babies in prams can be exposed to up to 60% more pollution than adults, study says

A review of factors surrounding the air pollution exposure to in-pram babies and mitigation strategies

New study say infants are exposed to dirtier air in prams because they are lower to the ground and closer to exhaust pipes. Covering your pram will help protect your baby from air pollution, NHS News reports, August 15 2018.


  • Exposure quantification of in-pram babies and potential mitigation efforts reviewed.
  • Pollutant exposure to in-pram babies can exceeds adult’s exposure by up to 60%.
  • First 1 m above road level important for exposure in breathing zone (~0.85 m) sitting babies
  • Breathing height of in-pram babies lies where concentrations are usually the greatest.
  • Both technology and community-driven measures are needed for exposure mitigation.


Air pollution exposure to in-pram babies poses a serious threat to their early childhood development, necessitating a need for effective mitigation measures. We reviewed the scientific and grey literature on in-pram babies and their personal exposure to traffic generated air pollutants such as particulate matter ≤10 μm (PM10), ≤2.5 μm (PM2.5), ≤0.10 μm (ultrafine particles) in size, black carbon and nitrogen oxides and potential mitigation pathways. In-pram babies can be exposed up to ~60% higher average concentrations depending on the pollutant types compared with adults. The air within the first few meters above the road level is usually most polluted. Therefore, we classified various pram types based on criteria such as height, width and the seating capacity (single versus twin) and assessed the breathing heights of sitting babies in various pram types available in the market. This classification revealed the pram widths between 0.56 and 0.82 m and top handle heights up to ~1.25 m as opposed to breathing height between 0.55 and 0.85 m, suggesting that the concentration within the first meter above the road level is critical for exposure to in-pram babies. The assessment of flow features around the prams suggests that meteorological conditions (e.g., wind speed and direction) and traffic-produced turbulence affect the pollution dispersion around them. A survey of the physicochemical properties of particles from roadside environment demonstrated the dominance of toxic metals that have been shown to damage their frontal lobe as well as cognition and brain development when inhaled by in-pram babies. We then assessed a wide range of active and passive exposure mitigation strategies, including a passive control at the receptor such as the enhanced filtration around the breathing zone and protection of prams via covers. Technological solutions such as creating a clean air zone around the breathing area can provide instant solutions. However, a holistic approach involving a mix of innovative technological solutions, community empowerment and exposure-centric policies are needed to help limit personal exposure of in-pram babies.

Ambient fine particulate matter reduces global and regional life expectancy

Air pollution reduces global life expectancy by more than one year, study finds

Air pollution shortens human lives by more than a year, according to a new study from a team of leading environmental engineers and public health researchers. Better air quality could lead to a significant extension of lifespans around the world, Phys.Org reports.

2018 Study Abstract

Exposure to ambient fine particulate matter (PM2.5) air pollution is a major risk for premature death. Here, we systematically quantify the global impact of PM2.5 on life expectancy. Using data from the Global Burden of Disease project and actuarial standard life table methods, we estimate global and national decrements in life expectancy that can be attributed to ambient PM2.5 for 185 countries. In 2016, PM2.5 exposure reduced average global life expectancy at birth by ∼1 year with reductions of ∼1.2–1.9 years in polluted countries of Asia and Africa. If PM2.5 in all countries met the World Health Organization Air Quality Guideline (10 μg m–3), we estimate life expectancy could increase by a population-weighted median of 0.6 year (interquartile range of 0.2–1.0 year), a benefit of a magnitude similar to that of eradicating lung and breast cancer. Because background disease rates modulate the effect of air pollution on life expectancy, high age-specific rates of cardiovascular disease in many polluted low- and middle-income countries amplify the impact of PM2.5 on survival. Our analysis adds to prior research by illustrating how mortality from air pollution substantially reduces human longevity.

Major Air Pollutant Could Be Halved By 2050

The Lancet Countdown on health benefits from the UK Climate Change Act: a modelling study for Great Britain

New analysis published in The Lancet Planetary Health, May 2018, shows that meeting the UK’s Climate Change Act commitments could cut nitrogen dioxide (NO2) air pollution by 50-60%, contributing to improved public health and longer life expectancy. The Act requires the UK to reduce greenhouse gas emissions by at least 80% on 1990 levels by 2050.


Climate change poses a dangerous and immediate threat to the health of populations in the UK and worldwide. We aimed to model different scenarios to assess the health co-benefits that result from mitigation actions.

In this modelling study, we combined a detailed techno-economic energy systems model (UK TIMES), air pollutant emission inventories, a sophisticated air pollution model (Community Multi-scale Air Quality), and previously published associations between concentrations and health outcomes. We used four scenarios and focused on the air pollution implications from fine particulate matter (PM2·5), nitrogen dioxide (NO2) and ozone. The four scenarios were baseline, which assumed no further climate actions beyond those already achieved and did not meet the UK’s Climate Change Act (at least an 80% reduction in carbon dioxide equivalent emissions by 2050 compared with 1990) target; nuclear power, which met the Climate Change Act target with a limited increase in nuclear power; low-greenhouse gas, which met the Climate Change Act target without any policy constraint on nuclear build; and a constant scenario that held 2011 air pollutant concentrations constant until 2050. We predicted the health and economic impacts from air pollution for the scenarios until 2050, and the inequalities in exposure across different socioeconomic groups.

NO2 concentrations declined leading to 4 892 000 life-years saved for the nuclear power scenario and 7 178 000 life-years saved for the low-greenhouse gas scenario from 2011 to 2154. However, the associations that we used might overestimate the effects of NO2 itself. PM2·5 concentrations in Great Britain are predicted to decrease between 42% and 44% by 2050 compared with 2011 in the scenarios that met the Climate Change Act targets, especially those from road traffic and off-road machinery. These reductions in PM2·5 are tempered by a 2035 peak (and subsequent decline) in biomass (wood burning), and by a large, projected increase in future demand for transport leading to potential increases in non-exhaust particulate matter emissions. The potential use of biomass in poorly controlled technologies to meet the Climate Change Act commitments would represent an important missed opportunity (resulting in 472 000 more life-years lost from PM2·5 in the low-greenhouse gas scenario and 1 122 000 more life-years lost in the nuclear power scenario from PM2·5 than the baseline scenario). Although substantial overall improvements in absolute amounts of exposure are seen compared with 2011, these outcomes mask the fact that health inequalities seen (in which socioeconomically disadvantaged populations are among the most exposed) are projected to be maintained up to 2050.

The modelling infrastructure created will help future researchers explore a wider range of climate policy scenarios, including local, European, and global scenarios. The need to strengthen the links between climate change policy objectives and public health imperatives, and the benefits to societal wellbeing that might result is urgent.

Reference. Briefing for Policymakers. Infographic.

Global Exposure to Air Pollution and its Disease Burden : SOGA 2018 Report

Over 95% of world’s population breathe dangerous air, study finds

More than 95% of the world’s population breathe unsafe air and the burden is falling hardest on the poorest communities, with the gap between the most polluted and least polluted countries rising rapidly, a comprehensive study of global air pollution has found.

More Information

  • State of global air 2018, stateofglobalair.
  • Over 95% of world’s population breathe dangerous air, study finds, euractiv, 17 Apr 2018.

Urban outdoor air pollution is a serious threat to healthy brain development which may set the conditions for neurodegenerative diseases

Severe Urban Outdoor Air Pollution and Children’s Structural and Functional Brain Development, From Evidence to Precautionary Strategic Action

According to the latest estimates, about 2 billion children around the world are exposed to severe urban outdoor air pollution. Transdisciplinary, multi-method findings from epidemiology, developmental neuroscience, psychology, and pediatrics, show detrimental outcomes associated with pre- and postnatal exposure are found at all ages. Affected brain-related functions include perceptual and sensory information processing, intellectual and cognitive development, memory and executive functions, emotion and self-regulation, and academic achievement. Correspondingly, with the breakdown of natural barriers against entry and translocation of toxic particles in the brain, the most common structural changes are responses promoting neuroinflammation and indicating early neurodegenerative processes. In spite of the gaps in current scientific knowledge and the challenges posed by non-scientific issues that influence policy, the evidence invites the conclusion that urban outdoor air pollution is a serious threat to healthy brain development which may set the conditions for neurodegenerative diseases. Such evidence supports the perspective that urgent strategic precautionary actions, minimizing exposure and attenuating its effects, are needed to protect children and their brain development.

… continue reading Severe Urban Outdoor Air Pollution and Children’s Structural and Functional Brain Development, From Evidence to Precautionary Strategic Action on Frontiers in Public Health, April 2018.

Featured image credit Bon Bahar.

Ambient air pollution and the risk of pregnancy loss

A prospective cohort study, January 2018

2018 Study Abstract

To estimate the association of pregnancy loss with common air pollutant exposure. Ambient air pollution exposure has been linked to adverse pregnancy outcomes, but few studies have investigated its relationship with pregnancy loss.

Prospective cohort study.

Not applicable.

A total of 343 singleton pregnancies in a multisite prospective cohort study with detailed protocols for ovulation and pregnancy testing.


Main Outcome Measure(s)
Timing of incident pregnancy loss (from ovulation).

The incidence of pregnancy loss was 28% (n = 98). Pollutant levels at women’s residences were estimated using modified Community Multiscale Air Quality models and averaged during the past 2 weeks (acute) and the whole pregnancy (chronic). Adjusted Cox proportional hazards models showed that an interquartile range increase in average whole pregnancy ozone (hazard ratio [HR] 1.12, 95% confidence interval [CI] 1.07–1.17) and particulate matter <2.5 μm (HR 1.13, 95% CI 1.03–1.24) concentrations were associated with faster time to pregnancy loss. Sulfate compounds also appeared to increase risk (HR 1.58, 95% CI 1.07–2.34). Last 2 weeks of exposures were not associated with loss.

In a prospective cohort of couples trying to conceive, we found evidence that exposure to air pollution throughout pregnancy was associated with loss, but delineating specific periods of heightened vulnerability await larger preconception cohort studies with daily measured air quality.

Air Pollution May Shorten Telomeres in Newborns – A Sign of Increased Health Risks

Shorter telomere length in cord blood associated with prenatal air pollution exposure: Benefits of intervention

A study conducted before and after the 2004 closure of a coal-burning power plant in Tongliang, China, found children born before the closure had shorter telomeres than those conceived and born after the plant stopped polluting the air.

“An individual’s telomere length at birth is known to influence their risk for disease decades later during adulthood,”

Tang, professor of Environmental Health Sciences at the Mailman School.

2018 Study Highlights

  • Compared telomere length (TL) in babies born before and after a coal plant shutdown.
  • Prenatal exposure coal pollutants (PAH) estimated by cord PAH-DNA adducts.
  • Shorter TL previously associated with certain adverse health outcomes in adults.
  • PAH-DNA adducts in cord blood associated with shorter TL.
  • The second (post- intervention) cohort had significantly longer TL compared to the first.


To examine the molecular benefits of the government action to close the local coal burning power plant in Tongliang County, Chongqing Municipality, we compared biologic markers and health outcomes in two successive birth cohorts enrolled before and after the plant was shut down. In this city, polycyclic aromatic hydrocarbons (PAH) were primarily emitted by the coal burning facility. We previously reported that cord blood levels of PAH-DNA adducts (a biomarker of exposure) and various adverse health outcomes were reduced in the second cohort, whereas levels of brain-derived neurotrophic factor/BDNF (a protein involved in neuronal growth) were increased. Here we assessed telomere length (TL), which has been associated with risk of certain chronic diseases, early mortality, aging and cognitive decline in adults.

The goals of the present study were to determine whether TL differed between the two cohorts and whether prenatal PAH exposure, estimated by PAH-DNA adducts in cord white blood cells of newborns in China, were predictive of shorter TL in cord blood, suggesting the potential accrual of risk of certain chronic diseases during the prenatal period. We explored relationships of TL with BDNF and neurodevelopmental outcomes, each previously associated with PAH-DNA adducts in these cohorts, as well as the potential mediating role of TL in the associations between adducts and neurodevelopmental outcomes.

We analyzed TL in cord blood of 255 newborns who also had data on PAH-DNA adducts, BDNF, and relevant covariates. Multiple regression analysis was carried out to test associations between adducts and TL and between TL and BDNF, adjusting for relevant covariates. In the subset with developmental quotient (DQ) scores from Gesell testing at age 2 (N = 210), we explored whether TL was a mediator of the relationship between PAH-DNA adducts and DQ scores by first examining the associations between cord adducts and DQ, cord adducts and TL, and TL and DQ, adjusting for the same covariates.

As hypothesized, the mean TL was significantly higher in the second cohort compared to the first cohort. Overall, PAH-DNA cord adducts were significantly and inversely correlated with TL. Multiple regression analysis showed a significant association between adducts and TL, after adjusting for key covariates: β (effect size per standard deviation adducts) = −0.019, p = .003. The regression coefficient of TL on (Ln) BDNF was also significant (β = 0.167, p < .001). Exploratory analysis, regressing TL on Gesell developmental scores, showed generally inverse, but not significant associations. TL was not, therefore, deemed to be a potential mediator of the association between adducts and developmental scores at age two.

This study provides the first evidence that prenatal PAH exposure from coal burning may adversely affect TL, with potential implications for future risk of chronic diseases including cardiovascular disease. The improvement in TL in the second cohort and the observed correlation between increased TL and higher levels of BDNF indicate direct benefits to the health and development of children resulting from the government’s closure of the power plant.

“The new study adds to the evidence that closing this coal-burning power plant was beneficial to the health and future wellbeing of newborns there,”
“Moreover, we know that lowering exposure to air pollution anywhere will be beneficial to children’s health and long-term potential.”

Perera, Director of the Columbia Center for Children’s Environmental Health, Professor of Environmental Health Sciences at the Mailman School of Public Health.

Chongqing featured image credit wikipedia.

Periconception Exposure to Air Pollution and Risk of Congenital Malformations

Air pollution around conception tied to birth defects

The amount of air pollution a mother is exposed to around the time of conception is directly linked with the risk of her baby being born with birth defects, according to a recent U.S. study. Image credit Dr Alexey Kulikov.


To evaluate the association between increased exposure to airborne fine particulate matter (PM2.5) during the periconception period with risk of congenital anomalies.

Study design
Using birth certificate data from the Ohio Department of Health (2006-2010) and PM2.5 data from the US Environmental Protection Agency’s 57 monitoring stations located throughout Ohio, the geographic coordinates of the mother’s residence for each birth were linked to the nearest PM2.5 monitoring station and monthly exposure averages were calculated. The association between congenital anomalies and increased PM2.5 levels was estimated, with adjustment for coexistent risk factors.

After adjustment for coexisting risk factors, exposure to increased levels of PM2.5 in the air during the periconception period was modestly associated with risk of congenital anomalies. Compared with other periconception exposure windows, increased exposure during the 1 month before conception was associated with the highest risk increase at lesser distances from monitoring stations. The strongest influences of PM2.5 on individual malformations were found with abdominal wall defects and hypospadias, especially during the 1-month preconception.

Increased exposure to PM2.5 in the periconception period is associated with some modest risk increases for congenital malformations. The most susceptible time of exposure appears to be the 1 month before and after conception. Although the increased risk with PM2.5 exposure is modest, the potential impact on a population basis is noteworthy because all pregnant women have some degree of exposure.