Q&A feature with Dr. Om P. Kurmi, University of Oxford

October 2, 2013 · 0 comments

Many thanks to Dr. Om P. Kurmi of the Clinical Trial Service Unit and Epidemiological Studies Unit, University of Oxford for taking the time to respond to questions about his research and thoughts on household air pollution issues.  Websites with additional information about his work are: http://www.ckbiobank.org and http://www.ctsu.ox.ac.uk/research.  There is also a bibliography of studies he has authored/co-authored with links to the abstracts or full text.

Briefly describe your current work/research on HAP/cookstoves. 

Currently, I am working as a cardio-respiratory epidemiologist on China Kadoorie Biobank (CKB) project. CKB is a blood based prospective study investigating the genetic and environmental causes of number of chronic diseases particularly IHD, Stroke, Chronic Respiratory Diseases, Cancer and Diabetes in over 0.5M participants (http://www.ckbiobank.org). The study is carried out in 10 regions (5 rural and 5 urban) of China (http://www.ckbiobank.org/links). Household air pollution is one of the major risk factor studied in our population, particularly related to chronic respiratory diseases, cancer and cardio-vascular health. The household air pollution data is collected using questionnaire and we are planning to estimate air pollution measurements for all CKB participants based on spatial interpolation, satellite–derived aerosol optical depth (AOD) measurements and land-use regression models. We will be analysing some of the blood based biomarkers related to exposure and chronic conditions.

What do you think are 1 or 2 of the main HAP/cookstove issues?

It is now well established that improved cook stoves (ICS) when well designed are able to reduce the exposure to smoke levels substantially by burning the solid fuel more efficiently. Global Alliance for Clean Cook stoves (http://www.cleancookstoves.org/ ) and other organisations are working tirelessly to be able to provide these ICS to the underprivileged particularly those living in low and medium income countries. However, there are number of issues that need to be addressed to make this program more effective. Firstly, the users need to be educated on the benefits of the ICS and stoves should be designed in such a way that it is easy to use and at the same time should be able to reduce the smoke levels substantially. Secondly, special focus should be given to empower the users in maintaining the sustainability of the stoves in long term without too much economic burden on the users.

Do you have suggestions on changes/additions to IAP Updates that would make it more useful to you? (Add funding page, inventory of IAP research projects, etc.)

I would be interested in adding a section where new-comers are able to interact with professionals both in terms of research and cook-stove programs. It would be good to have something like online mentorship. Alternatively, we could have number of groups where individuals interested in carrying out HAP projects can get some advice by writing an email to a group and the communication is kept open to all members.

Jay Graham – Cooking in Uganda (video)

September 26, 2013 · 0 comments

The video describes a project in Kampala, Uganda that’s promoting a new cooking technology — the TLUD stove, or Top Lit Updraft Stove — to reduce household air pollution that is estimated to kill over 20,000 people each year in Uganda.

The project is part of a USAID-funded project implemented by the NGO PATH that aims to increase the uptake and sustained use of improved cookstoves and cooking fuels. The TLUD has many positive aspects, yet many barriers remain.

Exhaled carbon monoxide and its associations with smoking, indoor household air pollution and chronic respiratory diseases

September 26, 2013 · 0 comments

Exhaled carbon monoxide and its associations with smoking, indoor household air pollution and chronic respiratory diseases among 512 000 Chinese adults. Int Jnl Epidem, Sept 2013.

Q Zhang, et al.

Background – Exhaled carbon monoxide (COex) level is positively associated with tobacco smoking and exposure to smoke from biomass/coal burning. Relatively little is known about its determinants in China despite the population having a high prevalence of smoking and use of biomass/coal.

Methods – The China Kadoorie Biobank includes 512 000 participants aged 30-79 years recruited from 10 diverse regions. We used linear regression and logistic regression methods to assess the associations of COex level with smoking, exposures to indoor household air pollution and prevalent chronic respiratory conditions among never smokers, both overall and by seasons, regions and smoking status.

Results – The overall COex level (ppm) was much higher in current smokers than in never smokers (men: 11.5 vs 3.7; women: 9.3 vs 3.2). Among current smokers, it was higher among those who smoked more and inhaled more deeply. Among never smokers, mean COex was positively associated with levels of exposures to passive smoking and to biomass/coal burning, especially in rural areas and during winter. The odds ratios (OR) and 95% confidence interval (CI) of air flow obstruction (FEV1/FVC ratio <0.7) for never smokers with COex at 7–14 and ≥14 ppm, compared with those having COex <7, were 1.38 (1.31–1.45) and 1.65 (1.52–1.80), respectively (Ptrend <0.001). Prevalence of other self-reported chronic respiratory conditions was also higher among people with elevated COex (P <0.05).

Conclusion –  In adult Chinese, COex can be used as a biomarker for assessing current smoking and overall exposure to indoor household air pollution in combination with questionnaires.

Oxidative potential of smoke from burning wood and mixed biomass fuels

September 26, 2013 · 0 comments

Oxidative potential of smoke from burning wood and mixed biomass fuels. Free Radical Research, Oct 2013.

Authors: O. P. Kurmi, et al.
E-mail: om.kurmi@ctsu.ox.ac.uk

More than half the world’s population still rely on burning biomass fuels to heat and light their homes and cook food. Household air pollution, a common component of which is inhalable particulate matter (PM), emitted from biomass burning is associated with increased vulnerability to respiratory infection and an enhanced risk of developing chronic obstructive pulmonary disease. In the light of an emerging hypothesis linking chronic PM exposure during childhood and increased vulnerability to respiratory diseases in adulthood, in a chain of events involving oxidative stress, reduced immunity and subsequent infection, the aim of this study was to characterise the oxidative potential (OP) of PM collected during the burning of wood and mixed biomass, whilst cooking food in the Kathmandu Valley, Nepal.

Our assessments were based on the capacity of the particles to deplete the physiologically relevant antioxidants from a validated, synthetic respiratory tract lining fluid (RTLF). Incubation of mixed biomass and wood smoke particles suspensions with the synthetic RTLF for 4 h resulted in a mean loss of ascorbate of 64.76 ± 16.83% and 83.37 ± 14.12% at 50 μg/ml, respectively. Reduced glutathione was depleted by 49.29 ± 15.22% in mixed biomass and 65.33 ± 13.01% in wood smoke particles under the same conditions. Co-incubation with the transition metal chelator diethylenetriaminepentaacetate did not inhibit the rate of ascorbate oxidation, indicating a negligible contribution by redox-active metals in these samples. The capacity of biomass smoke particles to elicit oxidative stress certainly has the potential to contribute towards negative health impacts associated with traditional domestic fuels in the developing world.

Control of household air pollution for child survival: estimates for intervention impacts

September 24, 2013 · 0 comments

Control of household air pollution for child survival: estimates for intervention impacts. BMC Public Health, Sept 2013, 13 (Suppl 3):S8.

Nigel G Bruce, et al.
Email: ngb@liv.ac.uk

Background – Exposure to household air pollution (HAP) from cooking with solid fuels affects 2.8 billion people in developing countries, including children and pregnant women. The aim of this review is to propose intervention estimates for child survival outcomes linked to HAP.

Methods – Systematic reviews with meta-analysis were conducted for ages 0-59 months, for child pneumonia, adverse pregnancy outcomes, stunting and all-cause mortality. Evidence for each outcome was assessed against Bradford-Hill viewpoints, and GRADE used for certainty about intervention effect size for which all odds ratios (OR) are presented as protective effects.

Results – Reviews found evidence linking HAP exposure with child ALRI, low birth weight (LBW), stillbirth, preterm birth, stunting and all-cause mortality. Most studies were observational and rated low/very low in GRADE despite strong causal evidence for some outcomes; only one randomised trial was eligible.Intervention effect (OR) estimates of 0.64 (95% CI: 0.55, 0.75) for ALRI, 0.71 (0.65, 0.79) for LBW and 0.66 (0.54, 0.81) for stillbirth are proposed, specific outcomes for which causal evidence was sufficient. Exposure-response evidence suggests this is a conservative estimate for ALRI risk reduction expected with sustained, low exposure. Statistically significant protective ORs were also found for stunting [OR=0.79 (0.70, 0.89)], and in one study of pre-term birth [OR=0.70 (0.54, 0.90)], indicating these outcomes would also likely be reduced. Five studies of all-cause mortality had an OR of 0.79 (0.70, 0.89), but heterogenity precludes a reliable estimate for mortality impact. Although interventions including clean fuels and improved solid fuel stoves are available and can deliver low exposure levels, significant challenges remain in achieving sustained use at scale among low-income households.

Conclusions – Reducing exposure to HAP could substantially reduce the risk of several child survival outcomes, including fatal pneumonia, and the proposed effects could be achieved by interventions delivering low exposures. Larger impacts are anticipated if WHO air quality guidelines are met. To achieve these benefits, clean fuels should be adopted where possible, and for other households the most effective solid fuel stoves promoted. To strengthen evidence, new studies with thorough exposure assessment are required, along with evaluation of the longer-term acceptance and impacts of interventions.

Development of a fuel efficient cookstove through a participatory bottom-up approach

September 12, 2013 · 0 comments

Energy, Sustainability and Society 2013, 3:16.

Development of a fuel efficient cookstove through a participatory bottom-up approach.

Vijay H Honkalaskar, et al.

Background – Since 1940s, other than a few success stories, the outcomes of efforts of development and dissemination of improved cookstoves a have not been so fruitful. This paper presents a bottom-up approach that was successfully implemented to develop a fuel-efficient cookstove in a tribal village that has resulted in a substantial reduction in firewood consumption.

Method – The approach ensured people’s participation at multiple stages of the process that started from project selection by capturing people’s needs/desires and studying the existing cooking practice to understand its importance in the local context. The performance of the cookstoves was evaluated by modifying a standard Water Boiling Test to accommodate the existing cooking practice. The improvement of the cookstove was achieved by fabricating a simple twisted tape assembly that could be placed on it without changing the existing cookstove.

Results – The optimization of the twisted tape device was first carried out in the laboratory and then implemented in the field. The field-level tests resulted in reduction of firewood consumption by around 21% which is a substantial improvement for such a device. It was also found that the improvement reduced soot accumulation by around 38% and time of cooking preparations by around 18.5%.

Conclusion – Overall, a bottom-up and participatory process that not only addressed people’s perceived needs but also ensured no changes in the existing cooking practice while providing an easy, low cost (around US$1.25) c, and locally manufacturable solution led to a highly successful improvement in the local cookstove that was accepted easily by the villagers.

Night Cooking Solar Cooker Using Molten Sodium Chloride as Phase Change Material

September 12, 2013 · 1 comment

Night Cooking Solar Cooker Using Molten Sodium Chloride as Phase Change Material, 2013.

O Parida, et al.

Solar cooking technology has to undergo a sea change if at all it’s to be accepted as the main source of cooking Energy. This is why a better model that incorporates both the traditional heat trapping cum concentrator mechanism and the latest techniques like that which uses a solar battery (phase change materials with high heat retention capability) can be used as the basic idea for the purpose.

A multi-purpose hybrid solar cooker using locally available materials can be used for night as well as day cooking. It will have two way supply of heat directly from sun during day time for cooking and from the phase change material during night time. This cooker preferably provides indoor cooking and it can have two arrangements, namely Grill and Oven, for cooking various Indian foods.

Sufficient care was taken for selecting the materials to be used in this solar cooker with price and availability
constraints across rural India. The design ideally can cook two traditional meals a day for a family of five. All assumptions for the design are based on this basic aim.

Modeling national average household concentrations of PM2.5 from solid cookfuel use for the global burden of disease -2010 assessment: results from cross-sectional assessments in India

September 12, 2013 · 0 comments

Environ Health. 2013 Sep 11;12(1):77.

Modeling national average household concentrations of PM2.5 from solid cookfuel use for the global burden of disease -2010 assessment: results from cross-sectional assessments in India.

Balakrishnan K, Ghosh S, Ganguli B, Sambandam S, Bruce N, Barnes DF, Smith KR.

BACKGROUND: Previous global burden of disease (GBD) estimates for household air pollution (HAP) from solid cookfuel use were based on qualitative indicators of exposure. Recent progress in GBD methodologies that use integrated–exposure–response (IER) curves for combustion particles required the development of models to quantitatively estimate average HAP levels experienced by large populations. Such models when developed at the country level also serve to inform public health intervention efforts. So, we aimed to develop a model to estimate national average household concentrations of PM2.5 from solid cookfuel use in India, together with estimates for 29 states.

METHODS: We monitored 24-hr household concentrations of PM2.5, in 617 rural households from 4 states in India on a cross-sectional basis between November 2004 and March 2005. We then, developed log-linear regression models that predict household concentrations as a function of multiple, independent household level variables available in national household surveys and generated national / state-level estimates using The Indian National Family and Health Survey (NFHS 2005).

RESULTS: The measured mean 24-hr concentration of PM2.5 in solid cookfuel using households ranged from 163 mug/m3 (95% CI: 143,183; Median 106; IQR: 191) in the living area to 609 mug/m3 (95% CI: 547,671; Median: 472; IQR: 734) in the kitchen area. Fuel type, kitchen type, ventilation, geographical location and cooking duration were found to be significant predictors of PM2.5 concentrations in the household level model. k-fold cross validation showed a fair degree of correlation (r = 0.56) between modeled and measured values. Extrapolation of the household level model to all solid cookfuel using households in India, covered by NFHS 2005, resulted in a modeled estimate of 450 mug/m3 (95% CI: 318,640) and 113 mug/m3 (95% CI: 102,127) , for national average 24-hr PM2.5 concentrations in the kitchen and living areas respectively.

CONCLUSIONS: The model affords substantial improvement over commonly used exposure indicators such as “percent solid cookfuel use” in HAP disease burden assessments, by providing some of the first estimates of national average HAP levels experienced in India. Model estimates also add considerable strength of evidence for framing and implementation of intervention efforts at the state and national levels.

WASHplus Weekly: Focus on Monitoring of Cookstoves

September 12, 2013 · 0 comments

WASHplus Weekly, Issue 115 September 6, 2013 | Focus on Monitoring & Evaluation of Cookstoves

This issue contains 2013 studies and resources on the monitoring and evaluation of cookstoves. Studies discuss the need for improved exposure assessment, the importance of multiple replicate tests, how to quantify stove adoption with stove use monitors, and other issues.

Country studies evaluate use of the Jiko Poa cookstove in Kenya and solar ovens in Nigeria. A rapid assessment in Ghana offers a rigorous modest-cost method for evaluating user uptake, field-based stove performance, and exposure to smoke. Other country studies discuss carbon monoxide measurements as a surrogate for particulate matter measurements in Guatemala and factors that influence cookstove adoption in Indonesia.

Biomass fuel use for household cooking in Swaziland: is there an association with anaemia and stunting?

August 29, 2013 · 1 comment

Trans R Soc Trop Med Hyg. 2013 Sep;107(9):535-44.

Biomass fuel use for household cooking in Swaziland: is there an association with anaemia and stunting in children aged 6-36 months?

Machisa M, Wichmann J, Nyasulu PS. Division of Epidemiology & Biostatistics, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown 2193, Johannesburg, South Africa.

Email: peter.nyasulu@monash.edu

BACKGROUND: This study is the second to investigate the association between the use of biomass fuels (BMF) for household cooking and anaemia and stunting in children. Such fuels include coal, charcoal, wood, dung and crop residues.

METHODS: Data from the 2006-2007 Swaziland Demographic and Health Survey (a cross-sectional study design) were analysed. Childhood stunting was ascertained through age and height, and anaemia through haemoglobin measurement. The association between BMF use and health outcomes was determined in multinomial logistic regression analyses. Various confounders were considered in the analyses.

RESULTS: A total of 1150 children aged 6-36 months were included in the statistical analyses, of these 596 (51.8%) and 317 (27.6%) were anaemic and stunted, respectively. BMF use was not significantly associated with childhood anaemia in univariate analysis. Independent risk factors for childhood anaemia were child’s age, history of childhood diarrhoea and mother’s anaemia status. No statistically significant association was observed between BMF use and childhood stunting, after adjusting for child’s gender, age, birth weight and preceding birth interval.

CONCLUSION: This study identified the need to prioritize childhood anaemia and stunting as health outcomes and the introduction of public health interventions in Swaziland. Further research is needed globally on the potential effects of BMF use on childhood anaemia and stunting.

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