Respiratory health effects of air pollution: Update on biomass smoke and traffic pollution

June 21, 2012 · 1 comment

J Allergy Clin Immunol 2012; 129:3-11

Respiratory health effects of air pollution: Update onbiomass smoke and traffic pollution

Mounting evidence suggests that air pollution contributes to the large global burden of respiratory and allergic diseases, including asthma, chronic obstructive pulmonary disease, pneumonia, and possibly tuberculosis. Although associations between air pollution and respiratory disease are complex, recent epidemiologic studies have led to an increased recognition of the emerging importance of traffic-related air pollution in both developed and less-developed countries, as well as the continued importance of emissions from domestic fires burning biomass fuels, primarily in the less-developed world.

Emissions from these sources lead to personal exposures to complex mixtures of air pollutants that change rapidly in space and time because of varying emission rates, distances from source, ventilation rates, and other factors. Although the high degree of variability in personal exposure to pollutants from these sources remains a challenge, newer methods for measuring and modeling these exposures are beginning to unravel complex associations with asthma and other respiratory tract diseases.

These studies indicate that air pollution from these sources is a major preventable cause of increased incidence and exacerbation of respiratory disease. Physicians can help to reduce the risk of adverse respiratory effects of exposure to biomass and traffic air pollutants by promoting awareness and supporting individual and community-level interventions.

Clean Cookstoves Must Be Rethought so They Actually Get Used in Developing World

June 21, 2012 · 0 comments

Source: National Geographic News, June 18, 2012

By Esther Duflo, Michael Greenstone, Rema Hanna, Radha Muthiah

Almost three billion people around the world—or 4 out of every 10 individuals—are exposed to high levels of smoke each day from traditional cookstoves. After water, indoor air pollution is the largest environmental threat to health in developing countries. Women and young children bear the brunt of these costs. Further, the reliance of the world’s poor on solid fuels for their cooking needs, in the end, affects us all through the release of carbon dioxide and black carbon that contribute to climate change.

Improved cookstoves and fuels, which emit less smoke and are more efficient, have great potential to improve respiratory health and stem the tide of climate change. In laboratories and under controlled conditions, they have been shown to reduce smoke exposure and greenhouse gas emissions. However, their effectiveness in the real world crucially depends on whether they are adopted and properly used when households make their own decisions about how to allocate time and resources.

A woman demonstrates a clean cookstove in India. Photo: U.S. Consulate Chennai, Flickr Creative Commons

In a recent working paper released by the Abdul Latif Jameel Poverty Action Lab, entitled “Up in Smoke:  The Influence of Household Behavior on the Long-Run Impact of Improved Cooking Stoves,” we presented results from the largest randomized evaluation of an improved cooking stove program to date.  The results were unfortunately discouraging:  through four years of follow-up, we found that the stoves did not lead to long-run improvements in health and fuel use remained unchanged.

[click to continue…]

Bookmark and Share

A more Durable Solar Cooker for Desert Refugee Camps – (Video)

June 21, 2012 · 0 comments

Pro-Inflammatory Effects of Cook Stove Emissions on Human Bronchial Epithelial Cells

June 7, 2012 · 0 comments

Indoor Air, June 2012

Pro-Inflammatory Effects of Cook Stove Emissions on Human Bronchial Epithelial Cells

Brie Hawley, John Volckens

Approximately half the world’s population uses biomass fuel for indoor cooking and heating. This form of combustion typically occurs in open fires or primitive stoves. Human exposure to emissions from indoor biomass combustion is a global health concern, causing an estimated 1.5 million premature deaths each year. Many ‘improved’ stoves have been developed to address this concern; however, studies that examine exposure-response with cleaner-burning, more efficient stoves are few.

The objective of this research was to evaluate the effects of traditional and cleaner burning stove emissions on an established model of the bronchial epithelium. We exposed well-differentiated, normal human bronchial epithelial (NHBE) cells to emissions from a single biomass combustion event using either a traditional three-stone fire or one of two energy-efficient stoves. Air-liquid interface cultures were exposed using a novel, aerosol-to-cell deposition system. Cellular expression of a panel of three pro-inflammatory markers was evaluated at 1 and 24 hours following exposure.

Cells exposed to emissions from the cleaner burning stoves generated significantly fewer amounts of pro-inflammatory markers than cells exposed to emissions from a traditional, three stone fire. Particulate matter emissions from each cookstove were substantially different, with the three-stone fire producing the largest concentrations of particles (by both number and mass). This study supports emerging evidence that more efficient cookstoves have the potential to reduce respiratory inflammation in settings where solid fuel combustion is used to meet basic domestic needs.

Lung Cancer Related to Wood-Smoke Exposure

June 7, 2012 · 2 comments

Journal of Thoracic Oncology: 31 May 2012

Clinical and Pathological Characteristics, Outcome and Mutational Profiles Regarding Non-Small-Cell Lung Cancer Related to Wood-Smoke Exposure

Arrieta, Oscar, et al.

Hypothesis: Although smoking is the major risk factor for non-small-cell lung cancer (NSCLC), other factors are also associated with lung carcinogenesis, such as wood-smoke exposure (WSE). This article has been aimed at suggesting that lung cancer related to cigarette smoking and lung cancer related to WSE have different clinical and genetic characteristics.

Experimental Design: A cohort of 914 lung cancer patients was prospectively studied; they had been treated at Mexico’s National Cancer Institute between 2007 and 2010. The associations of WSE and cigarette smoking with clinical characteristics, mutation profile, response to chemotherapy, and epidermal growth factor receptor tyrosine kinase inhibitors were analyzed, and overall survival (OS) rate was calculated. The trial was registered with ClinicalTrials.gov: NCT01023828.

Results: Of the lung cancer patients studied, 95.1% were classified as coming within the NSCLC histology subtype; 58% of the patients smoked cigarettes, 35% had a background of WSE (exposure to both cigarette smoke and wood smoke was documented in 12.1% of all patients), and 19.4% patients had no smoke-exposure background. WSE was associated with NSCLC and adenocarcinoma histology, and was also more frequently associated with epidermal growth factor receptor-mutations than cigarette-smoking patients were (50.0% cf. 19.4%), whereas KRAS mutations were less common in WSE patients (6.7%) than in smokers (21%). WSE patients had a higher epidermal growth factor receptor tyrosine kinase inhibitor response rate (39.7%) than smokers (18.8%). The NSCLC patient WSE group’s OS was longer (22.7 months) than that for smokers (13.8 months).

Conclusion: NSCLC patients who smoked tobacco/cigarettes differed from those having a background of WSE regarding tumor histology, mutation profile, response rate, and OS, indicating that different carcinogenic mechanisms were induced by these two types of smoke exposure.

Global Bang for the Buck: Cutting Black Carbon and Methane Benefits Both Health and Climate

June 7, 2012 · 0 comments

Env Health Perspec, June 2012

Global Bang for the Buck: Cutting Black Carbon and Methane Benefits Both Health and Climate

Bob Weinhold

Black carbon and methane have both been implicated in climate change. They also pose more direct human health threats, with black carbon constituting one component of fine particulate matter (PM2.5) and methane acting as a precursor of ground-level ozone. An international team of researchers analyzed 14 control measures for human-caused emissions of black carbon and methane to investigate health benefits that might occur in tandem with actions to help mitigate climate change in the next 20–40 years [EHP 120(6):831–839; Anenberg et al.].

Black carbon and methane are attractive climate-change mitigation targets because they are relatively short-lived in the atmosphere compared with carbon dioxide, with emission restrictions leading to fairly rapid benefits. Some of the primary sources of methane are fossil-fuel extraction, landfills, livestock, rice production, and wastewater treatment. Among major sources of black carbon are many types of incomplete combustion, including that tied to transportation, industry, housing, and burning of biomass. The 14 measures target sources such as fossil-fuel operations, vehicle emissions, landfill gas, sewage, agriculture, brick kilns, and biomass-fueled cook stoves.

Using published emissions scenarios as a basis for their calculations, the investigators estimate that if all 14 measures were fully implemented by 2030, average global population-weighted surface concentrations of PM2.5 could be reduced by 23–34% and ozone could drop 7–17% within the same period. That could prevent anywhere from 640,000 to 4,900,000 premature deaths annually, or about 1–7% of all deaths estimated to occur with the projected global population of 8.4 billion. The estimated health benefits would be due almost entirely to the black carbon control measures—with their attendant reductions in PM2.5, organic carbon, and non-methane ozone precursors—and would occur mostly in Asia and portions of Africa. Climate-change mitigation effects could have their own health benefits, although the authors didn’t attempt to calculate these. The authors accounted for just outdoor exposures from biomass-fueled cook stoves, not the well-documented health benefits of avoided indoor exposures; adding that information with a geographically appropriate distribution likely would substantially increase the number of avoided premature deaths.

The researchers used two atmospheric models, each of which predicted substantially different air-quality responses to the 14 measures and incorporated a wide range of data from numerous epidemiological studies as factors in their equations. Uncertainties and variations in the models and data suggest the number of averted premature deaths could be substantially higher or lower. The researchers didn’t address the difficulties or costs of implementing the 14 measures but did note that some related efforts are already under way on many continents, including adoption of European vehicle-emission standards and reductions in cook-stove emissions in some developing countries.

Malawi – Heat-absorbing ceramic stoves cut fuel use

June 6, 2012 · 0 comments

In Malawi, a new kind of cooking stove made from local materials requires much less fuel than traditional stoves, cutting the need for firewood and benefiting families and the environment.

Collida Harawa has spent a lot of her life gathering firewood. Like most villagers in the hilly district of Rumphi in northern Malawi, the 39-year-old peasant farmer relies on it as the only freely available fuel for cooking.

But collecting fuel is time-consuming and tiring. Harawa must walk up to seven kilometers (more than four miles) to the forest to fetch firewood, which she ties into a big bundle and carries the same distance home on her head.

And over time, the environmental consequences of fuel wood consumption have become clear, as Malawi’s forest cover dwindles and carbon emissions rise.

A young man demonstrates how to insert wood into an Esperanza cooking stove in Malawi’s Rumphi North region. The locally produced stoves use less wood, saving forests and easing the lives of families. Karen Sanje/AlertNet

But now Harawa and villagers like her are taking advantage of a new kind of cooking stove, made from locally available materials, that requires much smaller volumes of fuel than traditional stoves.

By doing so, they are not just saving themselves time and effort but are also helping to reduce emissions of carbon dioxide, which scientists say contributes to climate change.

The new brick and ceramic stove cuts use of wood fuel by up to 65 percent, according to John Bwati Gondwe, coordinator of the Esperanza stove project at the Eva Demaya Center, a local nongovernmental organization.

“That means a lot as far as protecting forests and reducing carbon emissions are concerned,” he said.

Trees use and store carbon dioxide during photosynthesis, and cutting them can not only increase carbon emissions but also disrupt the rainmaking process, called evapo-transpiration.

[click to continue…]

Bookmark and Share

Approaches to Low Carbon Energy and Development

June 5, 2012 · 0 comments

Approaches to Low Carbon Energy and Development: Bridging Concepts and Practice for Low Carbon Climate Resilient Development, 2012

Matthew Lockwood and Catherine Cameron. Learning Hub, Brighton: IDS.

Finally, it is particularly important to assess what is working for the scaling up of improvedcookstoves, because they are an obvious potential win-win intervention. A previous generation of improved cookstoves initiatives fared badly, because there was too much emphasis on technical design, often taking place in labs, and not enough on behavioural aspects, desirability and affordability.

Lung cancer risk of solid fuel smoke exposure: a systematic review and meta-analysis

June 5, 2012 · 0 comments

European Resp Jnl, May 31, 2012

Lung cancer risk of solid fuel smoke exposure: a systematic review and meta-analysis

Om Prakash Kurmi, et al.

The aim of this systematic review was to quantify the impact of biomass fuel and coal use on lung cancer and to explore reasons for heterogeneity in the reported effect sizes.

A systematic review of primary studies reporting the relationship between solid fuel use and lung cancer was carried out, based on pre-defined criteria. Studies that dealt with confounding factors were used in the meta-analysis. Fuel types, smoking, country, cancer cell type and gender were considered in sub-group analyses. Publication bias and heterogeneity were estimated.

The pooled effect estimate for coal smoke as a lung carcinogen (OR=1.82, 95% CI 1.60, 2.06) was greater than that from biomass smoke (OR=1.50, 95% CI 1.17, 1.94). The risk of lung cancer for solid fuel use was greater in females (OR=1.81, 95% CI 1.54, 2.12) compared to males (OR=1.16, 95% CI 0.79, 1.69). The pooled effect estimates were 2.33 (95% CI 1.72, 3.17) for adenocarcinoma, 3.58 (1.58, 8.12) for squamous cell carcinoma, and 1.57 (1.38, 1.80) for tumours of unspecified cell type.

These findings suggest that in-home burning of both coal and biomass is consistently associated with an increased risk of lung cancer.

Berkeley National Laboratory tackles pollution in Mongolia

June 1, 2012 · 0 comments

Hazy days: Berkeley lab tackles pollution in Mongolia – Source: Phys.org

June 1, 2012 – (Phys.org) — Scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) are known for designing high-efficiency cookstoves for Darfur and Ethiopia. Now they are applying their expertise to the windswept steppes of Mongolia, whose capital city, Ulaan Baatar, is among the most polluted cities in the world.

The scientists are working with the Millennium Challenge Corporation (MCC), a U.S. foreign aid agency, to improve air quality in the capital city by lowering emissions from outdated stoves and boilers. MCC has a five-year project in Mongolia to reduce poverty and promote sustainable economic growth. In 2010 the agency approached Berkeley Lab’s Ashok Gadgil, the driving force behind the Berkeley-Darfur stoves, to lend vision and technical expertise to solving Mongolia’s air quality problem. 

Through an interagency agreement between MCC and the Department of Energy, a small team of Berkeley Lab scientists led by Maithili Iyer and Larry Dale has been providing technical guidance and support to MCC on the implementation and monitoring and evaluation of the program, respectively. Their focus has been on the coal-burning stoves used for heating and cooking that are found in every ger, a round, tent-like structure that is a common form of housing in Ulaan Baatar.

“Since we have expertise in developing and testing stoves, MCC asked us to provide technical oversight of their program—from assessing the stove performance to providing feedback on the appropriate subsidy levels and other aspects of implementation,” said Iyer. “In the long run, Mongolia would benefit from moving away from coal-burning stoves altogether, but in the short term, promoting cleaner stoves is the most cost-effective way to maximize reductions in PM.”

Ulaan Baatar’s concentrations of particulate matter, or PM, are among the highest in the world. And the highest concentrations of PM, according to a 2011 World Bank report, have been measured in the ger districts, on the outskirts of the capital, inhabited largely by formerly nomadic families. “A lot of Mongolians are migrating to the cities for jobs and better schools for their children,” said Dale. “They continue to live in their tents and heat them when it’s minus 40 degrees outside with traditional stoves. Now half the city of 1.6 million, maybe more than half, is living in these ger districts.”

[click to continue…]

Bookmark and Share

← Previous Entries

Next Entries →