Below is an annotated bibliography of 10 journal articles authored or co-authored by Kirk Smith and that were published from 2008 – March 2010.
1. Lancet. 2009 Dec 19;374(9707):2104-14.
Public health benefits of strategies to reduce greenhouse-gas emissions: overview and implications for policy makers.
Haines A, McMichael AJ, Smith KR, Roberts I, Woodcock J, Markandya A, Armstrong BG, Campbell-Lendrum D, Dangour AD, Davies M, Bruce N, Tonne C, Barrett M, Wilkinson P.
London School of Hygiene and Tropical Medicine, London, UK. andy.haines@lshtm.ac.uk
This Series has examined the health implications of policies aimed at tackling climate change. Assessments of mitigation strategies in four domains-household energy, transport, food and agriculture, and electricity generation-suggest an important message: that actions to reduce greenhouse-gas emissions often, although not always, entail net benefits for health. In some cases, the potential benefits seem to be substantial. This evidence provides an additional and immediate rationale for reductions in greenhouse-gas emissions beyond that of climate change mitigation alone. Climate change is an increasing and evolving threat to the health of populations worldwide. At the same time, major public health burdens remain in many regions. Climate change therefore adds further urgency to the task of addressing international health priorities, such as the UN Millennium Development Goals. Recognition that mitigation strategies can have substantial benefits for both health and climate protection offers the possibility of policy choices that are potentially both more cost effective and socially attractive than are those that address these priorities independently.
2. Lancet. 2009 Dec 19;374(9707):2091-103.
Public health benefits of strategies to reduce greenhouse-gas emissions: health implications of short-lived greenhouse pollutants.
Smith KR, Jerrett M, Anderson HR, Burnett RT, Stone V, Derwent R, Atkinson RW, Cohen A, Shonkoff SB, Krewski D, Pope CA 3rd, Thun MJ, Thurston G.
School of Public Health, University of alifornia, Berkeley, CA 94720-7360, USA.
In this report we review the health effects of three short-lived greenhouse pollutants-black carbon, ozone, and sulphates. We undertook new meta-analyses of existing time-series studies and an analysis of a cohort of 352,000 people in 66 US cities during 18 years of follow-up. This cohort study provides estimates of mortality effects from long-term exposure to elemental carbon, an indicator of black carbon mass, and evidence that ozone exerts an independent risk of mortality. Associations among these pollutants make drawing conclusions about their individual health effects difficult at present, but sulphate seems to have the most robust effects in multiple-pollutant models. Generally, the toxicology of the pure compounds and their epidemiology diverge because atmospheric black carbon, ozone, and sulphate are associated and could interact with related toxic species. Although sulphate is a cooling agent, black carbon and ozone could together exert nearly half as much global warming as carbon dioxide. The complexity of these health and climate effects needs to be recognised in mitigation policies.
3. Lancet. 2009 Dec 5;374(9705):1917-29.
Public health benefits of strategies to reduce greenhouse-gas emissions: household energy.
Wilkinson P, Smith KR, Davies M, Adair H, Armstrong BG, Barrett M, Bruce N, Haines A, Hamilton I, Oreszczyn T, Ridley I, Tonne C, Chalabi Z.
London School of Hygiene and Tropical Medicine, London, UK. paul.wilkinson@lshtm.ac.uk
Energy used in dwellings is an important target for actions to avert climate change. Properly designed and implemented, such actions could have major co-benefits for public health. To investigate, we examined the effect of hypothetical strategies to improve energy efficiency in UK housing stock and to introduce 150 million low-emission household cookstoves in India. Methods similar to those of WHO’s Comparative Risk Assessment exercise were applied to assess the effect on health that changes in the indoor environment could have. For UK housing, the magnitude and even direction of the changes in health depended on details of the intervention, but interventions were generally beneficial for health. For a strategy of combined fabric, ventilation, fuel switching, and behavioural changes, we estimated 850 fewer disability-adjusted life-years (DALYs), and a saving of 0.6 megatonnes of carbon dioxide (CO(2)), per million population in 1 year (on the basis of calculations comparing the health of the 2010 population with and without the specified outcome measures). The cookstove programme in India showed substantial benefits for acute lower respiratory infection in children, chronic obstructive pulmonary disease, and ischaemic heart disease. Calculated on a similar basis to the UK case study, the avoided burden of these outcomes was estimated to be 12 500 fewer DALYs and a saving of 0.1-0.2 megatonnes CO(2)-equivalent per million population in 1 year, mostly in short-lived greenhouse pollutants. Household energy interventions have potential for important co-benefits in pursuit of health and climate goals.
4. Am J Epidemiol. 2009 Jul 15;170(2):211-20.
Effect of reducing indoor air pollution on women’s respiratory symptoms and lung function: the RESPIRE Randomized Trial, Guatemala.
Smith-Sivertsen T, Díaz E, Pope D, Lie RT, Díaz A, McCracken J, Bakke P, Arana B, Smith KR, Bruce N.
Department of Public Health and Primary Health Care, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway.
Exposure to household wood smoke from cooking is a risk factor for chronic obstructive lung disease among women in developing countries. The Randomized Exposure Study of Pollution Indoors and Respiratory Effects (RESPIRE) is a randomized intervention trial evaluating the respiratory health effects of reducing indoor air pollution from open cooking fires. A total of 504 rural Mayan women in highland Guatemala aged 15-50 years, all using traditional indoor open fires, were randomized to either receive a chimney woodstove (plancha) or continue using the open fire. Assessments of chronic respiratory symptoms and lung function and individual measurements of carbon monoxide exposure were performed at baseline and every 6 months up to 18 months. Use of a plancha significantly reduced carbon monoxide exposure by 61.6%. For all respiratory symptoms, reductions in risk were observed in the plancha group during follow-up; the reduction was statistically significant for wheeze (relative risk = 0.42, 95% confidence interval: 0.25, 0.70). The number of respiratory symptoms reported by the women at each follow-up point was also significantly reduced by the plancha (odds ratio = 0.7, 95% confidence interval: 0.50, 0.97). However, no significant effects on lung function were found after 12-18 months. Reducing indoor air pollution from household biomass burning may relieve symptoms consistent with chronic respiratory tract irritation.
5. J Expo Sci Environ Epidemiol. 2009 Jun 17.
Personal child and mother carbon monoxide exposures and kitchen levels: Methods and results from a randomized trial of woodfired chimney cookstoves in Guatemala (RESPIRE).
Smith KR, McCracken JP, Thompson L, Edwards R, Shields KN, Canuz E, Bruce N. aEnvironmental Health Sciences, School of Public Health, University of California, Berkeley, California, USA.
During the first randomized intervention trial (RESPIRE: Randomized Exposure Study of Pollution Indoors and Respiratory Effects) in air pollution epidemiology, we pioneered application of passive carbon monoxide (CO) diffusion tubes to measure long-term personal exposures to woodsmoke. Here we report on the protocols and validations of the method, trends in personal exposure for mothers and their young children, and the efficacy of the introduced improved chimney stove in reducing personal exposures and kitchen concentrations. Passive diffusion tubes originally developed for industrial hygiene applications were deployed on a quarterly basis to measure 48-hour integrated personal carbon monoxide exposures among 515 children 0-18 months of age and 532 mothers aged 15-55 years and area samples in a subsample of 77 kitchens, in households randomized into control and intervention groups. Instrument comparisons among types of passive diffusion tubes and against a continuous electrochemical CO monitor indicated that tubes responded nonlinearly to CO, and regression calibration was used to reduce this bias. Before stove introduction, the baseline arithmetic (geometric) mean 48-h child (n=270), mother (n=529) and kitchen (n=65) levels were, respectively, 3.4 (2.8), 3.4 (2.8) and 10.2 (8.4) p.p.m. The between-group analysis of the 3355 post-baseline measurements found CO levels to be significantly lower among the intervention group during the trial period: kitchen levels: -90%; mothers: -61%; and children: -52% in geometric means. No significant deterioration in stove effect was observed over the 18 months of surveillance. The reliability of these findings is strengthened by the large sample size made feasible by these unobtrusive and inexpensive tubes, measurement error reduction through instrument calibration, and a randomized, longitudinal study design. These results from the first randomized trial of improved household energy technology in a developing country and demonstrate that a simple chimney stove can substantially reduce chronic exposures to harmful indoor air pollutants among women and infants.
6. Ann N Y Acad Sci. 2008 Oct;1140:31-9.
Comparative environmental health assessments.
Smith KR. Global Environmental Health, University of California, School of Public Health, Berkeley, California, USA. krksmith@berkeley.edu
Conceptual and methodological issues in calculating and comparing the health impacts from environmental risk factors in ways that are not only compatible across environmental hazards but also can be fairly compared to burdens from nonenvironmental risk factors, such as poor nutrition, unsafe sex, and smoking, are discussed. It is emphasized that a focus on environmental health burden does not always produce priorities that correspond to those related to environmental quality alone. The methods when applied to China’s environmental and other risks using the Chinese burden of disease in terms of lost healthy life years as the metric are illustrated. Household environmental risks are still quite important in China, because of rural poverty, but have been exceeded by community environmental risks nationally. Global risks from climate are small at present, but have the potential to rise. Although not a major greenhouse gas emitter on a per capita basis compared to rich countries, China has already passed the threshold of imposing more global risk than it receives. The study ends with the suggestion that environmental risk assessment should use as a baseline estimates that are based on methods developed in international collaborative assessments, such as those in the WHO Comparative Risk Assessment, in order to foster comparability and policy and public confidence in the methods.
7. Res Rep Health Eff Inst. 2008 Oct;(135):3-41; discussion 43-52.
Mechanisms of particulate matter toxicity in neonatal and young adult rat lungs.
Pinkerton KE, Zhou Y, Zhong C, Smith KR, Teague SV, Kennedy IM, Ménache MG.
Center for Health and the Environment, Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California-Davis, 95616-8615, USA.
Particulate matter (PM*) has been associated with a variety of adverse health effects, primarily involving the cardiovascular and respiratory systems. Researchers continue to investigate biologic mechanisms that may explain how exposure to PM exacerbates or directly causes adverse effects. Particle composition may play a critical role in these effects. In this study we used a diffusion flame system to generate ultrafine iron, soot, and iron combined with
soot particles and exposed young adult and neonatal rats to different compositions of these particles. Young adult rats inhaled all three PM compositions on three consecutive days for 6 hours per day. Exposure to soot PM at 250 microg/m3 or to iron PM at 57 microg/m3 demonstrated no adverse respiratory effects. However, we observed mild pulmonary stress when the iron concentration was increased to 90 microg/m3. The most striking effects resulted when the rats inhaled PM composed of iron (45 microg/m3) combined with soot particles (total mass 250 microg/m3). This type of exposure produced significant indicators of oxidative stress, signs of inflammation, and increases in the levels of cytochrome P450 isozymes in the lungs. Repeated three-day exposure of neonatal rats to soot and iron particles in the second and the fourth weeks of life produced significant oxidative stress (elevations in oxidized and reduced glutathione) and ferritin induction. Neonatal rats exposed to PM in the second week of life also had a subtle but significant cell proliferation reduction in the centriacinar regions of the lungs. These findings suggest that iron combined with soot PM can lead to changes in the respiratory tract not found with exposure to iron or soot PM alone at similar concentrations. Unique effects in the neonate suggest that age may play an important role in susceptibility to inhaled particles.
8. BMC Int Health Hum Rights. 2008 Jun 5;8:7.
Self-rated health among Mayan women participating in a randomised intervention trial reducing indoor air pollution in Guatemala.
Díaz E, Bruce N, Pope D, Díaz A, Smith KR, Smith-Sivertsen T.
Department for Public Health and Primary Health Care, University of Bergen, Norway. esperanza.diaz@isf.uib.no
BACKGROUND: Indoor air pollution (IAP) from solid fuels is a serious health problem in low-income countries that can be alleviated using improved stoves. Although women are the principal users, few studies have investigated the self-assessed impact of the stoves on their health and lives.
METHODS: This study was conducted in rural highland Guatemala, involving 89 intervention and 80 control Mayan Indian young women (mean 27.8 years, SD 7.2). Outcomes were assessed after approximately 18 months use of the new stove. Our objectives were to compare self-rated health and change in health among women participating in a randomised control trial comparing a chimney stove with an open fire, to describe impacts on women’s daily lives and their perceptions of how reduced kitchen smoke affects their own and their children’s health.
RESULTS: On intention-to-treat analysis, 52.8% of intervention women reported improvement in health, compared to 23.8% of control women (p < 0.001). Among 84 intervention women who reported reduced kitchen smoke as an important change, 88% linked this to improvement in their own health, particularly for non-respiratory symptoms (for example eye discomfort, headache); 57% linked reduced smoke to improvement in their children’s health, particularly sore eyes.
CONCLUSION: Women’s perception of their health was improved, but although smoke reduction was valued, this was linked mainly with alleviation of non-respiratory symptoms like eye discomfort and headache. More focus on such symptoms may help in promoting demand for improved stoves and cleaner fuels, but education about more severe consequences of IAP exposure is also required.
9. Bull World Health Organ. 2008 May;86(5):390-398C.
Indoor air pollution from unprocessed solid fuel use and pneumonia risk in children aged under five years: a systematic review and meta-analysis.
Dherani M, Pope D, Mascarenhas M, Smith KR, Weber M, Bruce N.
Division of Public Health, University of Liverpool, Liverpool, England.
Reduction of indoor air pollution (IAP) exposure from solid fuel use is a potentially important intervention for childhood pneumonia prevention. This review updates a prior meta-analysis and investigates whether risk varies by etiological agent and pneumonia severity among children aged less than 5 years who are exposed to unprocessed solid fuels. Searches were made of electronic databases (including Africa, China and Latin America) without language restriction. Search terms covered all sources of IAP and wide-ranging descriptions of acute lower respiratory infections, including viral and bacterial agents. From 5317 studies in the main electronic databases (plus 307 African and Latin American, and 588 Chinese studies, in separate databases), 25 were included in the review and 24 were suitable for meta-analysis. Due to substantial statistical heterogeneity, random effects models were used. The overall pooled odds ratio was 1.78 (95% confidence interval, CI: 1.45-2.18), almost unchanged at 1.79 (95% CI: 1.26-2.21) after exclusion of studies with low exposure prevalence (< 15%) and one high outlier. There was evidence of publication bias, and the implications for the results are explored. Sensitivity subanalyses assessed the impact of control selection, adjustment for confounding, exposure and outcome assessment, and age, but no strong effects were identified. Evidence on respiratory syncytial virus was conflicting, while risk for severe or fatal pneumonia was similar to or higher than that for all pneumonia. Despite heterogeneity, this analysis demonstrated sufficient consistency to conclude that risk of pneumonia in young children is increased by exposure to unprocessed solid fuels by a factor of 1.8. Greater efforts are now required to implement effective interventions.
10. Annu Rev Public Health. 2008;29:11-25.
Co-benefits of climate mitigation and health protection in energy systems: scoping methods.
Smith KR, Haigler E.
Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, CA 94720-7360, USA. krksmith@berkeley.edu
Interventions in the energy sector offer significant opportunities for reducing both greenhouse and other health-damaging pollution, resulting in what are called “co-benefits.” The health community plays a critical role in evaluating such interventions to optimize progress of both sorts because both affect health. In detail, analyses require sophisticated modeling and specific local information. As a starting point, however, we offer here a set of scoping methods for obtaining a quick assessment of these co-benefits for interventions in the energy sector, the arena with the highest potential for significant co-benefits. Thus we combine relevant methods developed separately in recent years for cost-effectiveness assessments in the climate change, health, and development communities. We offer sample calculations, which illustrate the apparent high degree of co-benefit effectiveness for targeted interventions in the household energy sector in developing countries.