Abstract  In this article we discuss statistical techniques for modeling data from cohort studies that examine long-term effects of air pollution on children’s health by comparing data from multiple communities with a diverse pollution profile. Under a general multilevel modeling paradigm, we discuss models for different outcome types along with their connections to the generalized mixed effects models methodology. The model specifications include linear and flexible models for continuous lung function data, logistic and/or time-to-event models for symptoms data that account for misspecifications via hidden Markov models and Poisson models for school absence counts. The main aim of the modeling scheme is to be able to estimate effects at various levels (e.g., within subjects across time, within communities across subjects and between communities). We also discuss in detail various recurring issues such as ecologic bias, exposure measurement error, multicollinearity in multipollutant models, interrelationships between major endpoints and choice of appropriate exposure metrics. The key conceptual issues and recent methodologic advances are reviewed, with illustrative results from the Southern California Children’s Health Study, a 10-year study of the effects of air pollution on children’s respiratory health.

Abstract  Children and adolescents have been considered more susceptible to the effects of air pollution than adults. In order to investigate the responses of children of different ages to air pollution exposure, daily records of hospital admissions for children in five age groups (equal or less than 2 years of age, 3-5, 6-13, 14-19, and all ages together, i.e., from 0-19 years of age) were obtained from January 1993 to November 1997 in Sao Paulo, Brazil, and were compared to daily records of PM10, O3, SO2, CO and NO2 concentrations in ambient air. For each age group a generalized additive Poisson regression was fitted controlling for smooth functions of time, temperature, humidity, and days of the week, with an additional indicator for holidays. Polynomial distributed lag models were used to estimate the 7-day cumulative effect of each pollutant. Children 2 years or less were the most susceptible to the effects of all five pollutants with an increase of 9.4% (95% CI: 7.9, 10.9) in respiratory admissions associated with each interquartile range increase in PM10. The oldest group was the second most susceptible to air pollutants, with each interquartile range increase in PM10 associated with a 5.1% (95% CI: 0.3,9.8) increase in respiratory admissions. An interquartile range increase in CO was associated with an 11.3% (95% CI: 5.9, 16.8) increase in respiratory hospitalizations. When a multipollutant model was used, the effect of PM10 on respiratory admissions for all ages together was unchanged, while the SO2 and the other pollutants effect was substantially reduced. This study showed that daily respiratory hospital admissions for children and adolescents in Sa(tilde)o Paulo increased with air pollution, and that the largest effects were found for the youngest (2 years or less) and oldest (14-19 years) age groups.

Abstract  "Air Pollution and Health: Bridging the Gap from Sources to Health Outcomes," an international specialty conference sponsored by the American Association for Aerosol Research, was held to address key uncertainties in our understanding of adverse health effects related to air pollution and to integrate and disseminate results from recent scientific studies that cut across a range of air pollution-related disciplines. The Conference addressed the science of air pollution and health within a multipollutant framework (herein "multipollutant" refers to gases and particulate matter mass, components, and physical properties), focusing on five key science areas: sources, atmospheric sciences, exposure, dose, and health effects. Eight key policy-relevant science questions integrated across various parts of the five science areas and a ninth question regarding findings that provide policy-relevant insights served as the framework for the meeting. Results synthesized from this Conference provide new evidence, reaffirm past findings, and offer guidance for future research efforts that will continue to incrementally advance the science required for reducing uncertainties in linking sources, air pollutants, human exposure, and health effects. This paper summarizes the Conference findings organized around the science questions. A number of key points emerged from the Conference findings. First, there is a need for greater focus on multipollutant science and management approaches that include more direct studies of the mixture of pollutants from sources with an emphasis on health studies at ambient concentrations. Further, a number of research groups reaffirmed a need for better understanding of biological mechanisms and apparent associations of various health effects with components of particulate matter (PM), such as elemental carbon, certain organic species, ultrafine particles, and certain trace elements such as Ni, V, and Fe(II), as well as some gaseous pollutants. Although much debate continues in this area, generation of reactive oxygen species induced by these and other species present in air pollution and the resulting oxidative stress and inflammation were reiterated as key pathways leading to respiratory and cardiovascular outcomes. The Conference also underscored significant advances in understanding the susceptibility of populations, including the role of genetics and epigenetics and the influence of socioeconomic and other confounding factors and their synergistic interactions with air pollutants. Participants also pointed out that short-and long-term intervention episodes that reduce pollution from sources and improve air quality continue to indicate that when pollution decreases so do reported adverse health effects. In the limited number of cases where specific sources or PM2.5 species were included in investigations, specific species are often associated with the decrease in effects. Other recent advances for improved exposure estimates for epidemiological studies included using new technologies such as microsensors combined with cell phone and integrated into real-time communications, hybrid air quality modeling such as combined receptor-and emission-based models, and surface observations used with remote sensing such as satellite data.

Abstract  OBJECTIVE: To analyze the impact of the measures for securing quality air for the 2008 Beijing Olympic and Paralympics Games on air pollution index (API) in Beijing and forecast the aftereffects.

METHODS: The time-distribution of API in Beijing from 2004 to 2008 was described. The time sequence analysis was used and the autoregressive integrated moving average model (ARIMA) was chosen to establish an API forecasting model to predict the API in December, 2008.

RESULTS: From 2004 to 2008, the average API in March (120 +/- 66) was the highest followed by November (116 +/- 72) and the average API in July (83 +/- 28) was the lowest followed by August (77 +/- 27). The proportion of "excellent" and "good" days from 2004 to 2008 were 9.56% (35/366), 54.37% (199/366), 8.49% (31/365), 54.52% (199/365), 7.12% (26/365 ), 58.90% (215/365 ), 8.77% (32/365), 58.63% (214/365), 16.67% (61/366), 58.20% (213/366) respectively, with an increasing trend year by year (chi2(trend) = 11.397, P = 0.001). The model of ARIMA (1, 0, 0) fitted well; according to the prediction of the ARIMA (1, 0, 0) model, the decrease of API that attributed to interim measures during the Olympic Games was 37. 1% and the average API of December was 82.

CONCLUSION: The interim measures during the Olympic Games were effective on promoting air quality. After the Olympic Games, air quality would still remain good.

Abstract  An air quality index (AQI) is proposed for the City of Kanpur, India, for simplified public information and data interpretation. A maximum operator concept is used to determine the overall AQI; maximum value of sub-indices (of each pollutant) is taken as the overall AQI. The mathematical functions for calculating sub-indices are proposed based on health criteria of the USEPA and Indian air quality standards. The pollutants included in the AQI are: SO2, SPM (suspended particulate matter), O-3, NO2, PM10 (particulate matter with a diameter of 10 mum or less), and CO. The investigations into data interpretation using the AQI for Kanpur city have shown that air quality worsens (very poor to severe) in winter months and also during the early summer months (March, April, and part of May). These months are characterized by dusty winds resulting in high SPM. The air quality generally improves in monsoon and post-monsoon period (good to moderate) as rain washes out the pollutants. Over 95% of the time, sub-index values corresponding to SPM levels were responsible for overall AQI.

Abstract  A microwave digestion method in a closed vessel was developed for the determination of trace metals in atmospheric aerosols using inductively coupled plasma mass spectrometry (ICP-MS). A recovery study for the elements V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sb, and Pb was conducted using multi-elemental standard solutions, NIST 1633b Trace Elements in Coal Fly Ash, and NIST 1648 Urban Particulate Matter. A simple digestion method using only HNO3/H2O2 gave good recoveries (90%-108%) for all elements except Cr in SRM 1648, but yielded low recoveries for SRM 1633b. A more robust method using HNO3/H2O2/HF/H3BO3 yielded higher recoveries (82%-103%) for the lighter elements (V-Zn) in SRM 1633b, and improved the Cr recovery in SRM 1648, but decreased the Se recovery in both SRMs. A comparative analysis of aerosol samples obtained at a remote mountain location Nathiagali, Pakistan (2.5 km above mean sea level), and Mayville, New York, downwind from the highly industrialized Midwestern United States, was carried out using Instrumental Neutron Activation Analysis (INAA) for the elements Cr, Mn, Fe, Co, Zn, As, Se, and Sb. The simple digestion method yielded excellent agreement for Cr, Fe, Zn, As, Se, and Sb, with slopes of the ICP-MS vs. INAA regressions of 0.90-1.00 and R2 values of 0.96-1.00. The regressions for Mn and Co had slopes of 0.82 and 0.84 with R2 values of 0.83 and 0.82, respectively. Addition of HF/H3BO3 did not improve the correlation for any of the elements and degraded the precision somewhat. The technique provides sensitivity and accuracy for trace elements in relatively small aerosol samples used in atmospheric chemistry studies related to SO2 oxidation in cloud droplets. The ability to determine concentrations of a very large number of elements from a single analysis will permit source apportionment of various trace pollutants and hence strategies to control the sources of air pollution. This is particularly important as the health effects of particulate matter are increasingly recognized.

Abstract  The purpose of this manuscript is to describe the practical strategies developed for the implementation of the Minnesota Children's Pesticide Exposure Study (MNCPES), which is one of the first probability-based samples of multi-pathway and multi-pesticide exposures in children. The primary objective of MNCPES was to characterize children's exposure to selected pesticides through a combination of questionnaires, personal exposure measurements (i.e., air, duplicate diet, hand rinse), and complementary monitoring of biological samples (i.e., pesticide metabolites in urine), environmental samples (i.e., residential indoor/outdoor air, drinking water, dust on residential surfaces, soil), and children's activity patterns. A cross-sectional design employing a stratified random sample was used to identify homes with age-eligible children and screen residences to facilitate oversampling of households with higher potential exposures. Numerous techniques were employed in the study, including in-person contact by locally based interviewers, brief and highly focused home visits, graduated subject incentives, and training of parents and children to assist in sample collection. It is not feasible to quantify increases in rates of subject recruitment, retention, or compliance that resulted from the techniques employed in this study. Nevertheless, results indicate that the total package of implemented procedures was instrumental in obtaining a high percentage of valid samples for targeted households and environmental media.

Abstract  The paper gives the results of 4-year monitoring of the total mutagenic activity of snow samples from different Magnitogork areas in a test for induction of dominant lethal mutations (DLM) in the gametes of Drosophila melanogaster. An association was first found between the rate of DLM and the content of some chemical compounds in the ambient air and snow samples; moreover all the substances present in the samples, which had found genotoxic effects, showed a positive correlation with the rate of DLM. Furthermore, direct correlations were first established between the rate of DLM and the air pollution index and morbidity rates in 5-7-year-old children residing in the areas under study. The findings allow the test for induction of dominant lethal mutations (DLM) in the gametes of Drosophila melanogaster to be recommended due to its unique informative and prognostic value for monitoring ambient air pollution and for extensive use in the risk assessment system.

Abstract  Introduction. - Air quality is a public health issue and this article includes a reminder of the related causes and issues and a description of the monitoring of ambient air quality in France. It also provides a review of major developments in recent years of the pollutants measured.

Background. - Emissions of major air pollutants have declined significantly since the 1970s, and this is reflected in an overall improvement in the quality of ambient air. Nevertheless, various forms of air pollution remain a concern (in the case of photochemical pollution) and health data show that air pollution is still a cause of morbidity and mortality.

Viewpoints. - The fight against air pollution must remain a priority and requires multi-pollutant and multi-effect approaches. The National Health and Environment Program adopted during the Grenelle environment stakeholder consultation processes includes targets for reducing human exposure to air pollution, especially particulate matter, as well as measures to improve indoor air quality.

Conclusions. - In a context dominated by the struggle against the emission of greenhouse gases, problems of air quality should not be underestimated and policies relating to climate protection must be taken into account. (C) 2009 Published by Elsevier Masson SAS.

Abstract  Pollution indices aggregate concentrations of several water or air quality parameters into a single quantity to indicate the general status of pollution in a region. Several pollution index models are present in literature. However, their application for different cases may require modifications based on implementation goals and available data. In this study, modified pollution indices were used to evaluate the pollution status in the middle section of the Lower Seyhan River Basin by employing a geographical information system (GIS) software (ArcGIS 9.3) for data processing, estimations and evaluations. Air quality index (AQI) and water quality index (WQI) were utilized to evaluate air and water pollution levels, respectively. Moreover, a composite air-water quality index (AWQI) was developed to perform a general assessment about the overall pollution status. The WQI and AQI were calculated for 2004-2010 and 2007-2010, respectively. The AWQI was developed for the period of 2007-2010. Results indicated that for the available data and time frame considered in the study, air and water qualities were in good conditions (low pollution), in general. Yet, precautions could still be taken for improvement. Results also indicated the need for improvement of monitoring network for better assessment of the environmental quality in the whole basin. In general, GIS tools were very helpful in the development of the indices. (C) 2012 Elsevier Ltd. All rights reserved.

Abstract  This article presents the results of a qualitative Survey in social and environmental psychology conducted by the French Observatory of Indoor Air Quality (OQAI). The aim of this research was to identify the needs, expectations, and motivations, as well as the fears and reservations, of a sector of building professionals related to the development of an indoor air quality (IAQ) index intended to communicate and manage indoor air pollution in buildings. For this survey, we conducted semi-directive interviews with building managers (for schools, housing, and offices), personnel it the Ministries of health, the environment, and construction, as well as experts involved in IAQ. Content analysis of these interviews highlighted four main themes: 1) their representation of an IAQ index is primarily as a threat, and the perceived risks are as numerous as the perceived stakes; 2) they expect that any index will be adapted to specific environments rather than be standardized; 3) the behavioural dimension must be taken into account in risk management; 4) the conditions by which they can roaster and adopt the index must be considered.

Abstract  The study presents the modified formula of air quality index, based on Cairncross's concept of API index (DAPPS system for Cape Town, South Africa), enabling an assessment of additive effects of short-term exposure to the main air pollutants. The API index refers directly to health risk, since it is based on the factors of the total incremental daily mortality risk. The results of air quality classification using modified API were exemplified by the data originating from the monitoring station in Dabrowa Gornicza (urban background) for the year 2006.

Abstract  In order to monitor the distribution of atmospheric air ion and particulates in Tianzhu Mountain region, two observation points were established in Tianzhu Mountain in April, 1989. The results showed that the average concentration of air anode ion was 680/cm3, cathode ion 650/cm3. the range of single electrode coefficient is comfortable feeling, air quality index is 0.71 up to standard B grade (clean air), Total average concentration of suspended particulates was 0.242 mg/m3, average concentration of inhalation particulates was 0.168 mg/m3. Seventy percent particulates had diameters less than 10 microns, and thirty percent greater than 10 microns in total suspended particulates.

Abstract  16 U.S. EPA priority polycyclic aromatic hydrocarbons (PAHs) were quantified in total suspended ambient particulate matter (TSPM) collected from an industrial site in Agra (India) using gas chromatography. The major industrial activities in Agra are foundries that previously used coal and coke as fuel in cupola furnaces. These foundries have now switched over to natural gas. In addition, use of compressed natural gas has also been promoted and encouraged in automobiles. This study attempts to apportion sources of PAH in the ambient air and the results reflect the advantages associated with the change of fuel. The predominant PAHs in TSPM include high molecular weight (HMW) congeners BghiP, DbA, IP, and BaP. The sum of 16 priority PAHs had a mean value of 72.7 ± 4.7 ng m(-3). Potential sources of PAHs in aerosols were identified using diagnostic ratios and principal component analysis. The results reflect a blend of emissions from diesel and natural gas as the major sources of PAH in the city along with contribution from emission of coal, coke, and gasoline.

Abstract  Aerosol optical thickness (AOT) and atmospheric visibility are two important weather parameters. AOT reflects the state of the atmosphere,-and atmospheric visibility is widely used in various aspects of social life. Generally, it is reported in literatures that both of them are affected by Air Pollutants and other meteorological factors, such as surface pressure, ground temperature, wind speed, precipitation. In this paper, a statistic relationship expression is established between AOT and atmospheric visibility on the basis of the point-to-point meteorological observations. In the national region, the correlation between atmospheric visibility and weather factors indicates that the surface pressure has great influence on atmospheric visibility all the year round. And the influence based on precipitation is more obvious in spring and summer, mean-while wind speed and temperature play important roles in autumn and winter. A significant positive correlation was found between AOT and API. To express the relationship between atmospheric visibility and AOT, some computable models were utilized. According to the accuracy analysis, the cubic curve model and the power function model are more accurate. And both RMSE (root-mean-square error) of them is higher than 0.47. But the coefficient of cubic curve is more complex in practice. Finally, a simple estimation model of aerosol optical thickness based on meteorological station observed atmospheric visibility was conducted using power function. The Pearson coefficient between calculation of power function and observation is 0.73.

Abstract  Pesticides have adverse health effects and can be transported over long distances to contaminate sensitive ecosystems. To address problems caused by environmental pesticides we developed a multimedia multi-pollutant modeling system, and here we present an evaluation of the model by comparing modeled results against measurements. The modeled toxaphene air concentrations for two sites, in Louisiana (LA) and Michigan (MI), are in good agreement with measurements (average concentrations agree to within a factor of 2). Because the residue inventory showed no soil residues at these two sites, resulting in no emissions, the concentrations must be caused by transport; the good agreement between the modeled and measured concentrations suggests that the model simulates atmospheric transport accurately. Compared to the LA and MI sites, the measured air concentrations at two other sites having toxaphene soil residues leading to emissions, in Indiana and Arkansas, showed more pronounced seasonal variability (higher in warmer months); this pattern was also captured by the model. The model-predicted toxaphene concentration fraction on particles (0.5-5%) agrees well with measurement-based estimates (3% or 6%). There is also good agreement between modeled and measured dry (1:1) and wet (within a factor of less than 2) depositions in Lake Ontario. Additionally this study identified erroneous soil residue data around a site in Texas in a published US toxaphene residue inventory, which led to very low modeled air concentrations at this site. Except for the erroneous soil residue data around this site, the good agreement between the modeled and observed results implies that both the US and Mexican toxaphene soil residue inventories are reasonably good. This agreement also suggests that the modeling system is capable of simulating the important physical and chemical processes in the multimedia compartments.

Abstract  The PTEAM Study was the first large-scale probability-based study of personal exposure to particles. Sponsored by the U.S. Environmental Protection Agency (EPA) and the Air Resources Board of California, it was carried out by the Research Triangle Institute (RTI) and the Harvard University School of Public Health (HSPH). HSPH designed and constructed a 4-lpm, battery-operated personal monitor for inhalable particles (PM10) that could be worn comfortably for up to 14 hours by persons from 10 to 70 years old. The monitor was worn for two consecutive 12-hour periods (day and night) during the fall of 1990 by 178 participants representing 139,000 nonsmoking residents of Riverside, California. Nearly identical monitors were employed to collect concurrent indoor and outdoor samples. The monitors were equipped with a different sampling nozzle to collect fine particles (PM2.5). Population-weighted daytime personal PM10 exposures averaged 150 +/- 9 (SE) micrograms/m3, compared to concurrent indoor and outdoor concentrations of 95 +/- 6 micrograms/m3. This suggested the existence of excess mass near the person, a "personal cloud" that appeared related to personal activities. Fourteen of 15 prevalent elements also were evaluated in the personal samples. The two major indoor sources of indoor particles were smoking and cooking; even in these homes, however, more than half of the indoor particles came from outdoors, and a substantial portion of the indoor particles were of undetermined indoor origin. Outdoor concentrations near the homes were well correlated with outdoor concentrations at the central site, supporting the idea of using the central site as an indicator of of ambient concentrations over a wider area. Indoor concentrations were only weakly correlated with outdoor concentrations, however, and personal exposures were even more poorly correlated with outdoor concentrations. Elemental profiles were obtained for environmental tobacco smoke (ETS) (major contributions from potassium and chlorine) and cooking emissions (aluminum, iron, calcium, and chlorine). These profiles can be used in future source apportionment studies.