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Kirk R Smith

Publications and source records attributed to Kirk R Smith.

12 recordsLinked to original sources
PubMed2003

Characterization of non-methane hydrocarbons emitted from various cookstoves used in China.

Emission contributions from cookstoves to indoor, regional, and global air pollution largely depend on stove and fuel types. This paper presents a database on emission factors of speciated non-methane hydrocarbons (NMHCs) for 16 fuel/stove combinations burning 2 types of crop residue, wood, 4 types of coal, kerosene, and 3 types of gaseous fuels. The emission factors are presented both on a fuel mass basis (compound mass per fuel mass) and on a cooking task basis (compound mass per unit energy delivered to the pot). These fuel/stove combinations cover a large spectrum of the cookstoves used in both urban and rural households in China. Up to 54 hydrocarbons were identified, some of which are reactive precursors of photochemical smog. Based on published maximum incremental reactivity (MIR) values for NMHCs, we estimated stove-specific and fuel-specific ozone forming potentials (OFPs). The results indicate that raw coal powder, wood, and crop residues have higher OFP values than the other types of fuels tested. Strikingly, burning the coal briquette and honeycomb coal briquette produced OFP values more than 2 orders of magnitude lower than burning unprocessed (raw) coal, even in the same vented metal stove, for every 1 MJ delivered to the pot.

Air Pollutants↗
PubMed2003

Models to predict emissions of health-damaging pollutants and global warming contributions of residential fuel/stove combinations in China.

Residential energy use in developing countries has traditionally been associated with combustion devices of poor energy efficiency, which have been shown to produce substantial health-damaging pollution, contributing significantly to the global burden of disease, and greenhouse gas (GHG) emissions. Precision of these estimates in China has been hampered by limited data on stove use and fuel consumption in residences. In addition limited information is available on variability of emissions of pollutants from different stove/fuel combinations in typical use, as measurement of emission factors requires measurement of multiple chemical species in complex burn cycle tests. Such measurements are too costly and time consuming for application in conjunction with national surveys. Emissions of most of the major health-damaging pollutants (HDP) and many of the gases that contribute to GHG emissions from cooking stoves are the result of the significant portion of fuel carbon that is diverted to products of incomplete combustion (PIC) as a result of poor combustion efficiencies. The approximately linear increase in emissions of PIC with decreasing combustion efficiencies allows development of linear models to predict emissions of GHG and HDP intrinsically linked to CO2 and PIC production, and ultimately allows the prediction of global warming contributions from residential stove emissions. A comprehensive emissions database of three burn cycles of 23 typical fuel/stove combinations tested in a simulated village house in China has been used to develop models to predict emissions of HDP and global warming commitment (GWC) from cooking stoves in China, that rely on simple survey information on stove and fuel use that may be incorporated into national surveys. Stepwise regression models predicted 66% of the variance in global warming commitment (CO2, CO, CH4, NOx, TNMHC) per 1 MJ delivered energy due to emissions from these stoves if survey information on fuel type was available. Subsequently if stove type is known, stepwise regression models predicted 73% of the variance. Integrated assessment of policies to change stove or fuel type requires that implications for environmental impacts, energy efficiency, global warming and human exposures to HDP emissions can be evaluated. Frequently, this involves measurement of TSP or CO as the major HDPs. Incorporation of this information into models to predict GWC predicted 79% and 78% of the variance respectively. Clearly, however, the complexity of making multiple measurements in conjunction with a national survey would be both expensive and time consuming. Thus, models to predict HDP using simple survey information, and with measurement of either CO/CO2 or TSP/CO2 to predict emission factors for the other HDP have been derived. Stepwise regression models predicted 65% of the variance in emissions of total suspended particulate as grams of carbon (TSPC) per 1 MJ delivered if survey information on fuel and stove type was available and 74% if the CO/CO2 ratio was measured. Similarly stepwise regression models predicted 76% of the variance in COC emissions per MJ delivered with survey information on stove and fuel type and 85% if the TSPC/CO2 ratio was measured. Ultimately, with international agreements on emissions trading frameworks, similar models based on extensive databases of the fate of fuel carbon during combustion from representative household stoves would provide a mechanism for computing greenhouse credits in the residential sector as part of clean development mechanism frameworks and monitoring compliance to control regimes.

Air Pollutants↗
PubMed2003

The burden of disease from indoor air pollution in developing countries: comparison of estimates.

Four different methods have been applied to estimate the burden of disease due to indoor air pollution from household solid fuel use in developing countries (LDCs). The largest number of estimates involves applying exposure-response information from urban ambient air pollution studies to estimate indoor exposure concentrations of particulate air pollution. Another approach is to construct child survival curves using the results of large-scale household surveys, as has been done for India. A third approach involves cross-national analyses of child survival and household fuel use. The fourth method, referred to as the 'fuel-based' approach, which is explored in more depth here, involves applying relative risk estimates from epidemiological studies that use exposure surrogates, such as fuel type, to estimates of household solid fuel use to determine population attributable fractions by disease and age group. With this method and conservative assumptions about relative risks, 4-5 percent of the global LDC totals for both deaths and DALYs (disability adjusted life years) from acute respiratory infections, chronic obstructive pulmonary disease, tuberculosis, asthma, lung cancer, ischaemic heart disease, and blindness can be attributed to solid fuel use in developing countries. Acute respiratory infections in children under five years of age are the largest single category of deaths (64%) and DALYs (81%) from indoor air pollution, apparently being responsible globally for about 1.2 million premature deaths annually in the early 1990s.

Air Pollutants↗
PubMed2002

Why particles?

Explore the source record for details and available documents.

Air Pollutants↗
PubMed2002

Exposure efficiency: an idea whose time has come?

Exposure efficiency, the fraction of material released from a source that is eventually inhaled or ingested, is arguably the simplest of all possible descriptions of the link between pollutant emissions and population exposures. This paper, prepared in late 1999 for the SGOMSEC Workshop, notes that several groups of researchers independently developed the concept of exposure efficiency in the late 1980s and early 1990s but argues that the potential importance of exposure efficiency in risk analysis and life cycle assessment has only recently been appreciated. The paper reviews the history of the concept; discusses and summarizes previous estimates of exposure efficiency for particulate matter and other air pollutants; presents new values for fine particulate matter emitted from power plants and mobile sources in the United States; and illustrates how preliminary estimates of exposure efficiency might be developed. The authors assert that in order for the concept of exposure efficiency to achieve its full potential exposure efficiency estimates for a wide variety of pollutants and sources must be developed and that both the results and methods must be made widely available and accessible to the community of risk assessors and life cycle analysts.

Air Pollutants↗
PubMed2002

Place makes the poison: Wesolowski Award Lecture - 1999.

Paracelsus, the Renaissance figure often called the father of toxicology, is given that credit partly for being the first to note that "the dose makes the poison." Modern understanding of the importance of personal exposure in determining dose, however, indicates that to a large extent as well, "place makes the poison." The relative proximity of a pollution source to people has just as big an impact on its importance as a hazard as does the relative toxicity (including chemical nature and size distribution) of its emissions. The exposure effectiveness (or intake fraction) of common air pollution sources, for example, varies over nearly four orders of magnitude. A place-makes-the-poison perspective not only identifies new relationships and priorities among known sources, but also reveals an entirely new landscape of sources and potential control measures. It, thus, has profound economic and policy implications, which will be examined in the context of particle air pollution in different parts of the world.

Air Pollutants↗
PubMed2002

Outdoor air pollution and acute respiratory infections among children in developing countries.

Acute respiratory infections (ARIs) are the most common cause of illness and death in children in the developing world. This review focuses on outdoor air pollutants associated with pediatric ARI mortality and morbidity. Studies were identified using MEDLINE and other electronic databases. Four studies showed an increase in infant mortality in relation to outdoor air pollution. Short-term follow-up and time-series studies suggest that air pollutants act as risk factors for respiratory infection. Air pollution exposure increases the incidence of upper- and lower-respiratory infections in children. Because complex pollution mixtures are present in the studied urban areas, pollutant levels at which ARI risk would be expected to increase cannot be determined. Children may be at greater risk, given the poor environmental and nutritional conditions prevalent in developing countries.

Acute Disease↗
PubMed2002

The origin, fate, and health effects of combustion by-products: a research framework.

Incomplete combustion processes can emit organic pollutants, metals, and fine particles. Combustion by-products represent global human and environmental health challenges that are relevant not only in heavily industrialized nations, but also in developing nations where up to 90% of rural households rely on unprocessed biomass fuels for cooking, warmth, and light. These issues were addressed at the Seventh International Congress on Combustion By-Products, which convened 4-6 June 2001 in Research Triangle Park, North Carolina. This congress included a diverse group of multidisciplinary researchers and practitioners who discussed recent developments and future goals in the control of combustion by-products and their effects of exposure on human and ecologic health. Participants recommended that interdisciplinary, coordinated research efforts should be focused to capitalize on the important potential synergisms between efforts to reduce the adverse human health effects linked to exposures to combustion by-products and broader efforts to reduce greenhouse gas emissions and save energy through efficiency. In this article we summarize the principal findings and recommendations for research focus and direction.

Bioelectric Energy Sources↗
PubMedDate not supplied

Occupational health in India.

The population of India has crossed the billion mark; only one other country (China) shares this distinction. A declining female population and low literacy are negatives in an otherwise vibrant country. The empowerment of females and their role in society has become a point of debate, and radical economic changes are likely, to allow India to join the global economy. Problems in occupational health and safety (OHS) include: OHS legislation that covers only a minority of the working population; child labour; a physician-driven OHS model; little attention to industrial hygiene; poor surveillance of occupational diseases (making it impossible to gauge the burden of illness due to occupational exposures); and a fragile OHS academic base. A silver lining comprises the inclusion of OHS in national health policy and the decision by the Indian Medical Association to educate its members in occupational health. India urgently requires modern OHS legislation with adequate enforcement machinery, and establishment of centres of excellence in occupational medicine, to catch up with the rest of the world.

Chemical Industry↗