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Birmingham New Street railway station in the UK has recently undergone a substantial redevelopment at a cost of more than £600 million. However, the unique underground tunnel geography of the platforms has remained virtually unchanged, which means that diesel exhaust gases are effectively trapped causing a daily build-up of air pollution in the station. A new ventilation system has been installed consisting of 98 bi-directional fans that are meant to disperse any air pollution out of the station. Unfortunately, the fans were triggered by carbon dioxide levels that do not significantly correlate with more serious air pollutants such as nitrogen oxides. In August 2018, new workplace exposure limits (WELs) were introduced for nitrogen monoxide (NO) and nitrogen dioxide (NO2). However, during a recent measurement campaign, one of the new WELs would have been exceeded on most days. Network Rail has undertaken to introduce a number of interventions, including the installation of new nitrogen monoxide/dioxide sensors to drive the ventilation system together with new sonic wind sensors, encouraging train operating companies to switch off idling diesel engines and encouraging more electric/hybrid trains.

Dementia is an umbrella term for a range of conditions that affect how the brain works and, in particular, the ability to remember, think and reason. It mainly affects older people, both men and women, and gets worse over time. In recent years, there has been growing interest in the possibility that exposure to outdoor air pollution could increase the risk of dementia. COMEAP reviewed epidemiological and experimental studies and concluded that it is likely that air pollution contributes to a decline in mental ability and dementia in older people. The most likely way this occurs is through effects on the circulatory system. It is known that air pollutants, particularly fine particles, can affect the heart and blood vessels, including those of the brain. These effects are linked to vascular dementia, which is caused by damage to the blood vessels in the brain. Experimental studies suggest that air pollution may also stimulate immune cells in the brain, which can then damage nerve cells. It is also likely that some nano-sized (ultrafine) particles can enter the brain, either by transport along the olfactory nerve or by entering the circulation and crossing the blood-brain barrier. These particles may cause direct damage. Nonetheless, based on the available evidence, it does not seem likely that this is an important mechanism for the development of dementia. Recommendations were made for further research which would help develop the evidence on this important topic.

The present study aimed to assess BTEX (benzene, toluene, ethylbenzene, and xylenes) concentrations, their sources and health risk estimates in Shiraz, the fifth-most populous city in Iran. Air samples were collected from 19 sampling stations across Shiraz using passive samplers. Identification and quantification of BTEX were conducted by a Gas Chromatography–Mass Spectrometry (GC–MS). Spatial distribution of BTEX compounds were mapped by inverse distance weighting (IDW) procedure. Monte Carlo simulation was employed to assess the corresponding carcinogenic and non-carcinogenic risks of BTEX concentrations. BTEX concentrations were higher than current levels in Western countries but lower than concentrations measured in East Asia. Analysis of individual BTEX ratios and their strong correlation indicated that fresh traffic emissions were the main contributor to these compounds in Shiraz, with additional sources contributing to toluene (e.g. industrial solvent use) and benzene (e.g. evaporative emissions). The incremental lifetime cancer risk (ILCR) for benzene and ethylbenzene were estimated to be 6.49 × 10−7- 1.27 × 10-5 and 1.21 × 10−7- 2.37 × 10-6, respectively, exceeding the WHO and EPA recommendations. The current evaluation of BTEX sources and associated health risks will assist policymakers to define action plans to minimize BTEX exposure in Shiraz and similar cities in the Middle East.

Objective. To estimate the point prevalence and likely ranges of pregnancy-induced hypertension, preeclampsia, gestational diabetes, low birth weight and preterm delivery in Latin America and the Caribbean, and evaluate the heterogeneity of the estimates. Methods. We conducted a systematic review and meta-analysis of observational studies reporting the prevalence of maternal and perinatal adverse outcomes in populations in Latin American and the Caribbean published between 2000 and 2019 in English, Spanish, or Portuguese. We searched PubMed, Embase, and LILACS. We estimated the point prevalence and evaluated overall heterogeneity and, in sub-group analyses, heterogeneity by study design and level of bias. Results. Of 1087 records retrieved, 50 articles were included in the review: two on hypertensive disorders of pregnancy, 14 on pre-eclampsia, six on gestational diabetes, nine on low birth weight and 19 on preterm birth. No meta-analysis for hypertensive disorders of pregnancy could be done because of the small number of studies. Point prevalence estimates and 95% confidence intervals (CIs) for pre-eclampsia, gestational diabetes, low birth weight, and preterm birth were: 6.6% (95% CI: 4.9%, 8.6%), 8.5% (95% CI: 3.9%, 14.7%), 8.5% (95% CI: 7.2%, 9.8%), and 10.0% (95% CI: 8.0%, 12.0%), respectively. We observed substantial heterogeneity overall and by study design. No major differences in estimates were observed by level of bias. Conclusions. The results of this study provide updated estimates of some of the most prevalent adverse pregnancy and perinatal outcomes in Latin America and the Caribbean. They highlight that important heterogeneity exists in prevalence estimates, which may reflect the diversity of populations in the region. Objetivo. Estimar la prevalencia puntual y los rangos probables de hipertensión provocada por embarazo, preeclampsia, diabetes gestacional, peso bajo al nacer y parto prematuro en América Latina y el Caribe, y evaluar la heterogeneidad de las estimaciones. Métodos. Se llevó a cabo una revisión sistemática y metanálisis de los estudios de observación que notificaron la prevalencia de resultados adversos perinatales y maternos en poblaciones de América Latina y el Caribe, publicados entre los años 2000 y 2019 en inglés, español o portugués. Se realizaron búsquedas en PubMed, Embase y LILACS. Se estimó la prevalencia puntual y se evaluó la heterogeneidad general y, en los análisis de subgrupos, la heterogeneidad según el diseño del estudio y nivel de sesgo. Resultados. De 1 087 registros recuperados, se incluyeron 50 artículos en la revisión: 2 sobre los trastornos hipertensivos en el embarazo, 14 sobre preeclampsia, 6 sobre la diabetes gestacional, 9 sobre peso bajo al nacer y 19 sobre parto prematuro. No se pudo realizar ningún metanálisis de los trastornos hipertensivos del embarazo debido al número reducido de estudios. Las estimaciones de prevalencia puntual y los intervalos de confianza (IC) del 95% para la preeclampsia, la diabetes gestacional, el peso bajo al nacer y el parto prematuro fueron: 6,6% (IC de 95%: 4,9%, 8,6%), 8,5% (IC de 95%: 3,9%, 14,7%), 8,5% (IC de 95%: 7,2%, 9,8%) y 10,0% (IC de 95%: 8,0%, 12,0%), respectivamente. Se observó una heterogeneidad significativa en general, así como según el diseño del estudio. No se advirtieron grandes diferencias en las estimaciones según el nivel del sesgo. Conclusiones. Los resultados de este estudio ofrecen cálculos actualizados de algunos de los resultados adversos perinatales y del embarazo con mayor prevalencia en América Latina y el Caribe. Estos resultados ponen de manifiesto que existe una gran heterogeneidad en las estimaciones de prevalencia, que podría reflejar la diversidad de la población de la región. Objetivo. Estimar a prevalência pontual e os intervalos prováveis de hipertensão induzida pela gravidez, pré-eclâmpsia, diabetes gestacional, baixo peso ao nascer e parto prematuro na América Latina e no Caribe e avaliar a heterogeneidade das estimativas. Métodos. Realizou-se uma revisão sistemática com metanálise de estudos observacionais que relatam a prevalência de desfechos maternos e perinatais adversos em populações da América Latina e do Caribe, publicados entre 2000 e 2019 em inglês, espanhol ou português. Os bancos de dados PubMed, Embase e LILACS foram pesquisados. Estimou-se a prevalência pontual e avaliou-se a heterogeneidade geral, bem como, em análises de subgrupo, a heterogeneidade por delineamento do estudo e o nível de viés. Resultados. De 1 087 registros encontrados, 50 artigos foram incluídos na revisão: dois sobre distúrbios hipertensivos da gravidez, 14 sobre pré-eclâmpsia, seis sobre diabetes gestacional, nove sobre baixo peso ao nascer e 19 sobre parto prematuro. Não foi possível realizar metanálise para distúrbios hipertensivos da gravidez devido ao pequeno número de estudos. As estimativas de prevalência pontual e intervalos de confiança de 95% (IC) para pré-eclâmpsia, diabetes gestacional, baixo peso ao nascer e parto prematuro foram: 6,6%; (IC 95%: 4,9–8,6%), 8,5% (IC 95%: 3,9–14,7%), 8,5% (IC 95%: 7,2–9,8%) e 10,0% (IC 95%: 8,0– 12,0%), respectivamente. Observou-se heterogeneidade considerável, tanto em geral como por delineamento de estudo. Não foram observadas diferenças importantes nas estimativas por nível de viés. Conclusões. Os resultados deste estudo fornecem estimativas atualizadas de alguns dos desfechos gestacionais e perinatais adversos mais prevalentes na América Latina e no Caribe. Destacam a existência de uma importante heterogeneidade nas estimativas de prevalência, o que pode refletir a diversidade das populações da região.

High NO2 concentrations (long term average of 383 µg/m3 in 2016/2017) recorded at Birmingham New Street railway station have resulted in the upgrade of the bi-directional fan system to aid wind dispersion within the enclosed platform environment. This paper attempts to examine how successful this intervention has been in improving air quality for both passengers and workers within the station. New air pollution data in 2020 has enabled comparisons to the 2016/2017 monitoring campaign revealing a 23–42% decrease in measured NO2 concentrations. The new levels of NO2 are below the Occupational Health standards but still well above the EU Public Health Standards. This reduction, together with a substantial decrease (up to 81%) in measured Particulate Matter (PM) concentrations, can most likely be attributed to the new fan system effectiveness. Carbon Monoxide levels were well below Occupational and Public Health Standards at all times. The COVID19 pandemic “initial lockdown” period has also allowed an insight into the resultant air quality at lower rail-traffic intensities, which produced a further reduction in air pollutants, to roughly half the pre-lockdown concentrations. This study shows the scope of improvement that can be achieved through an engineering solution implemented to improve the ventilation system of an enclosed railway station. Further reduction in air pollution would require additional approaches, such as the removal of diesel engine exhaust emissions via the adoption of electric or diesel-electric hybrid powered services.

Automatic geocoding methods have become popular in recent years, facilitating the study of the association between health outcomes and the place of living. However, rather few studies have evaluated geocoding quality, with most of them being performed in the US and Europe. This article aims to compare the quality of three automatic online geocoding tools against a reference method. A subsample of 300 handwritten addresses from hospital records was geocoded using Bing, Google Earth, and Google Maps. Match rates were higher (> 80%) for Google Maps and Google Earth compared with Bing. However, the accuracy of the addresses was better for Bing with a larger proportion (> 70%) of addresses with positional errors below 20m. Generally, performance did not vary for each method for different socioeconomic status. Overall, the methods showed an acceptable, but heterogeneous performance, which may be a warning against the use of automatic methods without assessing quality in other municipalities, particularly in Chile and Latin America. Resumen: Los métodos automáticos de geocodificación se han convertido en algo popular durante los últimos años para facilitar el estudio de la asociación entre resultados de salud y lugar para vivir. No obstante, más bien pocos estudios han evaluado la calidad de la geocodificación, siendo realizados la mayoría de ellos en EE.UU. y Europa. El objetivo de este artículo es comparar la calidad de tres herramientas automáticas de geocodificación en línea frente a un método de referencia. La submuestra de 300 direcciones escritas a mano, procedentes del registro hospitalario, se geocodificaron usando Bing, Google Earth y Google Maps. Los porcentajes de coincidencia fueron mayores (> 80%) en el caso de Google Maps y Google Earth comparados con Bing. Sin embargo, la precisión de las direcciones fue mejor con Bing, en una proporción más grande (> 70%) de direcciones que tenían errores de posición por debajo de 20m. En general, el rendimiento no varió en cada método para diferentes niveles estatus socioeconómico. En general, los métodos mostraron un rendimiento aceptable, pero heterogéneo. Esto previene contra el uso de métodos automáticos sin evaluar la calidad en otras ciudades, particularmente en Chile y Latinoamérica. Resumo: Os métodos de geocodificação automática se tornaram populares nos últimos anos para facilitar o estudo da associação entre desfechos de saúde e lugar de residência. Entretanto, poucos estudos avaliaram a qualidade da geocodificação, e a maioria dos estudos existentes foi realizada nos Estados Unidos e Europa. O estudo teve como objetivo comparar a qualidade de três ferramentas de geocodificação eletrônica automática em relação a um método de referência. Foi geocodificada uma subamostra de 300 endereços anotados à mão em prontuários hospitalares, usando Bing, Google Earth e Google Maps. As taxas de correspondência dos registros foram mais altas (> 80%) com Google Maps e Google Earth, comparado com Bing. Entretanto, a acurácia dos endereços foi melhor com Bing, com uma proporção maior (> 70%) de endereços com erros de localização menores que 20 metros. Em geral, o desempeno não variou para cada método de acordo com condição socioeconômica. Os métodos apresentaram desempenho geral aceitável, porém heterogêneo. Os resultados servem de alerta contra o uso de métodos automáticos sem avaliar a qualidade em outras cidades, particularmente no Chile e no resto da América Latina.

Urban residents are frequently exposed to high levels of traffic-derived air pollution for short time periods, often (but not exclusively) during commuting. Although chronic air pollution exposure and health effects, including neurological effects on children and older adults, are known to be correlated, causal effects of acute pollution exposure on brain function in healthy young adults remain sparsely investigated. Neuroinflammatory accounts suggest effects could be delayed by several hours and could affect attention, especially in social contexts. Using a controlled atmosphere chamber, we exposed 81 healthy young adults to either diluted diesel exhaust (equivalent to polluted roadside environments) or clean air for one hour. Half of each group immediately completed a selective attention task to assess cognitive control; remaining participants completed the task after a 4-hour delay. Cognitive control was significantly poorer after diesel versus clean air exposure for those in the delay but not immediate test condition, suggesting an inflammatory basis for this acute negative effect of air pollution on cognition. These findings provide the first experimental evidence that acute diesel exposure, comparable to polluted city streets, causes a negative effect on cognitive control several hours later. These findings may explain commuter mental fatigue and support clean-air initiatives.

Many rail services around the world continue to use diesel as the primary fuel source and enclosed railway stations have been identified as a possible hotspot for exposure to harmful diesel exhaust exposures. Little is known about the occupational exposure to air pollution for railway station workers due to their mobility around the station and variations in station design. A detailed understanding of the concentration of black carbon (BC), a diesel exhaust tracer, inside railway stations and the factors driving occupational exposures is required to minimize occupational exposure. Real-time personal exposure to BC was measured during 60 work-shifts encompassing different roles at three large enclosed railway stations of different design in London, Birmingham and Edinburgh (UK). Sampling was conducted by the train station workers over a period of 27 days between January 2017 to October 2018. Worker shift-mean BC exposures ranged 0.6–20.8 μg m−3 but 1-min peak exposures reached 773 μg m−3, with train dispatchers experiencing the highest BC exposures. Station design, job role, and frequency of diesel trains were the main drivers of occupational BC exposure. Elevated exposures for some station workers indicate that mitigation measures to reduce their exposure should be implemented to lower the risk of occupational health impacts. These could include improving ventilation and reducing engine emissions. Funding for open access charge: CRUE-Universitat Jaume I

Individuals who get involved in the disinfection of public settings using sodium hypochlorite might suffer adverse health effects. However, scarce information is available on the potential oxidative stress damage caused at low concentrations typically used for disinfection. We aimed to assess whether exposure to sodium hypochlorite during the COVID-19 pandemic causes oxidative stress damage in workers engaged in disinfection tasks. 75 operators engaged in the disinfection of public places were recruited as the case group, and 60 individuals who were not exposed to disinfectant were chosen as the control group. Spot urine samples were collected before (BE) and after exposure (AE) to disinfectants in the case group. Likewise, controls provided two spot urine samples in the same way as the case group. Urinary malondialdehyde (MDA) levels were quantified by forming thiobarbituric acid reactive substances in the urine. In addition, the concentration of 8-hydroxy-2′-deoxyguanosine (8-OHdG) in the urine was determined using an ELISA kit. Results showed significant differences in the urinary levels of oxidative stress markers, where median 8-OHdG (AE case: 3.84 ± 2.89 μg/g creatinine vs AE control 2.54 ± 1.21 μg/g creatinine) and MDA (AE case: 169 ± 89 μg/g creatinine vs AE control 121 ± 47 μg/g creatinine) levels in case group AE samples were 1.55 and 1.35-times higher than the control group AE samples (P, Graphical abstract Unlabelled Image

A rich body of literature indicates that environmental factors interact with the human microbiome and influence its composition and functions contributing to the pathogenesis of diseases in distal sites of the body. This systematic review examines the scientific evidence on the effect of environmental toxicants, air pollutants and endocrine disruptors (EDCs), on compositional and diversity of human microbiota. Articles from PubMed, Embase, WoS and Google Scholar where included if they focused on human populations or the SHIME® model, and assessed the effects of air pollutants and EDCs on human microbiome. Non-human studies, not written in English and not displaying original research were excluded. The Newcastle-Ottawa Scale was used to assess the quality of individual studies. Results were extracted and presented in tables. 31 studies were selected, including 24 related to air pollutants, 5 related to EDCs, and 2 related to EDC using the SHIME® model. 19 studies focussed on the respiratory system (19), gut (8), skin (2), vaginal (1) and mammary (1) microbiomes. No sufficient number of studies are available to observe a consistent trend for most of the microbiota, except for streptococcus and veillionellales for which 9 out of 10, and 3 out of 4 studies suggest an increase of abundance with exposure to air pollution. A limitation of the evidence reviewed is the scarcity of existing studies assessing microbiomes from individual systems. Growing evidence suggests that exposure to environmental contaminants could change the diversity and abundance of resident microbiota, e.g. in the upper and lower respiratory, gastrointestinal, and female reproductive system. Microbial dysbiosis might lead to colonization of pathogens and outgrowth of pathobionts facilitating infectious diseases. It also might prime metabolic dysfunctions disrupting the production of beneficial metabolites. Further studies should elucidate the role of environmental pollutants in the development of dysbiosis and dysregulation of microbiota-related immunological processes. ispartof: SCIENCE OF THE TOTAL ENVIRONMENT vol:816 ispartof: location:Netherlands status: published

Missing data from air quality datasets is a common problem, but is much more severe in small cities or localities. This poses a great challenge for environmental epidemiology as high exposures to pollutants worldwide occur in these settings and gaps in datasets hinder health studies that could later inform local and international policies. Here, we propose the use of imputation methods as a tool to reconstruct air quality datasets and have applied this approach to an air quality dataset in Temuco, a mid-size city in Chile as a case-study. We attempted to reconstruct the database comparing five approaches: mean imputation, conditional mean imputation, K-Nearest Neighbor imputation, multiple imputation and Bayesian Principal Component Analysis imputation. As a base for the imputation methods, linear regression models were fitted for PM2.5 against other air quality and meteorological variables. Methods were challenged against validation sets where data was removed artificially. Imputation methods were able to reconstruct the dataset with good performance in terms of completeness, errors, and bias, even when challenged against the validations sets. The performance improved when including covariates from a second monitoring station in Temuco. K-Nearest Neighbor imputation showed slightly better performance than multiple imputation for error (25% vs. 27%) and bias (2.1% vs. 3.9%), but presented lower completeness (70% vs. 100%). In summary, our results show that the imputation methods can be a useful tool in reconstructing air quality datasets in a real-life situation.

Composting facilities workers are potentially exposed to different volatile organic compounds (VOCs). This study aims to investigate the potential exposure to benzene, toluene, ethylbenzene and xylenes (BTEX) compounds among workers of composting facilities by measuring un-metabolized BTEX in urine and to investigate the effect that several lifestyle factors (i.e. smoking and residential traffic), using personal protective equipment, and religious practices such as Ramadan fasting can have on the urinary BTEX concentrations. We assessed concentrations of BTEX in the urine of a composting facility workers. Samples were collected in May 2018. Overall, 25 workers chosen as the exposed group and 20 inhabitants living close to the composting facility as a control group. The urine samples were collected from studied subjects. Identification and quantification of un-metabolized BTEX was performed using a headspace gas chromatography-mass spectrometry (GC-MS). Detailed information of participants was gathered by a comprehensive questionnaire. The geometric mean levels of urinary benzene, toluene, ethylbenzene, m‑p xylene, and o‑xylene in the exposed subjects were 1.27, 2.12, 0.54, 1.22 and 1.51 μg/L, respectively; 1.4 to 3.7-time higher than values in control group (p 0.05). Post-shift levels were significantly higher than pre-shift for all chemicals (p 0.05). Smoking habits, exposure to environmental tobacco smoke, and Ramadan fasting predicted urinary BTEX levels. Personal protective equipment which included a simple N95 mask did not protected workers from BTEX emissions. Composting facilities represent a significant source BTEX emissions and exposure for staff. More effective protective strategies are required to minimize exposure and related occupational hazards.

Children are highly susceptible to environmental contaminants as their physiology and some metabolic pathways differ from adults. The present cross-sectional study aimed to assess whether exposure to benzene, toluene, ethylbenzene, o,p-xylene, and m-xylene (BTEX) affects oxidative DNA damage in street children using a biomonitoring approach. Thirty-five boys (7–13 years of age), exposed by working at a busy intersection, and 25 unexposed boys of similar age and living in the neighborhood near the busy intersection were recruited. Urinary un-metabolized BTEX levels were quantified by a headspace gas chromatography-mass spectrometry (GC–MS). Urinary malonaldehyde (MDA) was measured with spectrophotometry. Sociodemographic and lifestyle conditions information was collected by interviews using administered questionnaires. Exposed subjects provided urine before (BE) and after work exposure (AE), while unexposed boys gave a single morning sample. Urinary BTEX concentrations in BE samples were similar to unexposed. Concentrations in AE samples were 2.36-fold higher than observed in BE samples (p < 0.05) and higher than those in the unexposed group (p < 0.05). In addition, urinary MDA levels in AE samples were 3.2 and 3.07-times higher than in BE samples and in the unexposed group (p < 0.05). Environmental tobacco smoke (ETS) increased urinary BTEX and MDA levels in both groups. Our findings confirm that street children working at busy intersections are significantly exposed to BTEX, which is associated with oxidative stress. Implementing protective measures is crucial to reduce exposure and to improve health outcomes in this group.

Concentrations of metals and metalloids derived mainly from anthropogenic activities have increased considerably in the environment. Metals might be associated with increase reactive oxygen species (ROS) damage, potentially related to several health outcomes. This study has recruited 200 adult participants, including 110 males and 90 females in Shiraz (Iran), to investigate the relationship between chronic exposure to metals and ROS damage by analyzing malondialdehyde (MDA) and 8-Oxo-2'-deoxyguanosine (8-OHdG) concentrations, and has evaluated the associations between chronic metal exposure and ROS damage using regression analysis. Our findings showed participants are chronically exposed to elevate As, Ni, Hg, and Pb levels. The mean urinary concentrations of 8-OHdG and MDA were 3.8 ± 2.35 and 214 ± 134 µg/g creatinine, respectively. This study shows that most heavy metals are correlated with urinary ROS biomarkers (R ranges 0.19 to 0.64). In addition, regression analysis accounting for other confounding factors such as sex, age, smoking status, and teeth filling with amalgam highlights that Al, Cu, Si and Sn are associated with 8-OHdG concentrations, while an association between Cr and MDA and 8-OHdG is suggested. Smoking cigarettes and water-pipe is considered a significant contributory factor for both ROS biomarkers (MDA and 8-OHdG)., peer-reviewed

Purpose Indoor and outdoor factors affect personal exposure to air pollutants. Type of cooking appliance (i.e. gas, electricity), and residential location related to traffic are such factors. This research aims to investigate the effect of cooking with gas and electric appliances, as an indoor source of aerosols, and residential traffic as outdoor sources, on personal exposures to particulate matter with an aerodynamic diameter lower than 2.5 μm (PM2.5), black carbon (BC), and ultrafine particles (UFP). Methods Forty subjects were sampled for four consecutive days measuring personal exposures to three aerosol pollutants, namely PM2.5, BC, and UFP, which were measured using personal sensors. Subjects were equally distributed into four categories according to the use of gas or electric stoves for cooking, and to residential traffic (i.e. houses located near or away from busy roads). Results/conclusion Cooking was identified as an indoor activity affecting exposure to aerosols, with mean concentrations during cooking ranging 24.7–50.0 μg/m3 (PM2.5), 1.8–4.9 μg/m3 (BC), and 1.4 × 104–4.1 × 104 particles/cm3 (UFP). This study also suggest that traffic is a dominant source of exposure to BC, since people living near busy roads are exposed to higher BC concentrations than those living further away from traffic. In contrast, the contribution of indoor sources to personal exposure to PM2.5 and UFP seems to be greater than from outdoor traffic sources. This is probably related to a combination of the type of building construction and a varying range of activities conducted indoors. It is recommended to ensure a good ventilation during cooking to minimize exposure to cooking aerosols.

Urinary benzene, toluene, ethylbenzene, and xylenes (BTEX) can be used as a reliable biomarker of exposure to these pollutants. This study was aimed to investigate the urinary BTEX concentration in operators of healthcare waste (HCW) autoclaves. This cross-sectional study was conducted in selected hospitals in Tehran, Iran between April and June 2017. Twenty operators (as the case group) and twenty control subjects were enrolled in the study. Personal urine samples were collected at the beginning and end of the work shift. Urinary BTEX were measured by a headspace gas chromatography-mass spectrometry (GC/MS). A detailed questionnaire was used to gather information from subjects. Results showed that the median of urinary benzene, toluene, ethylbenzene, m-p xylene, and o-xylene levels in the exposed group were 3.26, 3.36, 0.84, 3.94 and 4.48 μg/L, respectively. With the exception of ethylbenzene, subjects in the exposed group had significantly higher urinary BTEX levels than control group (p 0.05). Urinary BTEX concentrations in the exposed case group were 2.5-fold higher than in the control group. There was a significant relationship between the amount of generated waste per day and the urinary BTEX in the exposed group. Smoking status and type of autoclave used were also identified as predictors of urinary BTEX concentrations. The healthcare waste treatment autoclaves can be considered as a significant BTEX exposure source for operators working with these treatment facilities. The appropriate personal protection equipment and control measures capable in reducing BTEX exposure should be provided to HCW workers to reduce their exposures to BTEX.

Use of a Chemical Mass Balance model is one of the two most commonly used approaches to estimating atmospheric concentrations of cooking aerosol. Such models require the input of chemical profiles for each of the main sources contributing to particulate matter mass and there is appreciable evidence from the literature that not only the mass emission but also the chemical composition of particulate matter varies according to the food being prepared and the style of cooking. In this study, aerosol has been sampled in the laboratory from four different styles of cooking, i.e. Indian, Chinese, Western and African cooking. The chemical profiles of molecular markers have been quantified and are used individually within a Chemical Mass Balance model applied to air samples collected in a multi-ethnic area of Birmingham, UK. The model results give a source contribution estimate for cooking aerosol which is consistent with other comparable UK studies, but also shows a very low sensitivity of the model to the cooking aerosol profile utilised. A survey of local restaurants suggested a wide range of cooking styles taking place which may explain why no one profile gives an appreciably better fit in the CMB model.

In 2012, the World Health Organization's International Agency for Research on Cancer (IARC) reclassified diesel engine exhaust and related ambient air pollution to be carcinogenic and associated with increased mortality from lung cancer. This could have critical consequences for both public and occupational health in enclosed railway stations where ventilation is often inadequate. Recent policies encouraging a shift to public transport, along with increasing passenger and train numbers, have led to a variety of co-benefits, including improved health and well-being from increased walking and cycling. This paper considers the unintended consequences of a reduction of air quality in crowded enclosed railway stations and concludes with a number of possible interventions to ensure that public health is not affected, especially by air pollution from stationary diesel trains. Pollution from electric trains can also lead to poor air quality due to the production of metal-rich ultrafine particles from brake linings, friction between wheel and rail, and from overhead pantographs. Current occupational health standards are not suitable for enclosed railway stations and need to be reconsidered in the light of the IARC findings. More measurements of the levels of particulates and nitrogen dioxide in enclosed railway stations need to be undertaken and published.

Per- and polyfluoroalkyl substances (PFASs) are a ubiquitous group of persistent chemicals distributed globally in the environment. Skin aging is a notorious process that is prematurely induced by the interaction between endogenous and exogenous factors, including exposure to environmental chemicals. The existing evidence suggests that skin absorption of PFASs through dermal contact may be an important route of exposure to these chemicals in humans. On the other hand, PFASs intake by other routes may lead to PFASs bioaccumulation in the skin via tissue bio-distribution. Additionally, the presence of PFASs in consumer and cosmetic products combined with their daily close contact with the skin could render humans readily susceptible to dermal absorption. Therefore, chronic low-dose dermal exposure to PFASs can occur in the human population, representing another important route of exposure to these chemicals. Studies indicate that PFASs can threaten skin health and contribute to premature skin aging. Initiation of inflammatory-oxidative cascades, induction of DNA damage such as telomere shortening, dysregulation of genes engaged in dermal barrier integrity and its functions, signaling of the mitogen activated protein kinase (MAPK) pathway, and last but not least the down-regulation of extracellular matrix (ECM) components are among the most likely mechanisms by which PFASs can contribute to premature skin aging. ispartof: JOURNAL OF HAZARDOUS MATERIALS vol:405 ispartof: location:Netherlands status: published

Heavy metals are neurotoxic, associated with brain dysfunction, and have been linked with cognitive decline in adults. This study was aimed to characterize chronic exposure to metals (Cd, Be, Co, Hg, Sn, V, Al, Ba, Cr, Cu, Fe, Li, Mn, Ni, Pb, and Zn) and metalloids (As, B, Sb) and assess its impact on cognitive performance of Tehran's residents, capital of Iran. Scalp hair samples gathered from 200 volunteered participants (110 men and 90 women), aged 14–70 years and quantified by inductively coupled plasma atomic emission spectroscopy (ICP-OES). Attention and executive function, two measures of cognitive performance, were characterized using the trail making test (TMT) part A and B, respectively. Mental flexibility was characterized as the Delta TMT B-A scores and cognitive efficiency or dissimulation as the ration between TMT B and A scores. A comprehensive questionnaire was used to gather information on demographic and socioeconomic as well as lifestyle and health status. The highest and lowest mean concentrations were observed for B (325 μg/g) and As (0.29 μg/g), respectively. Results indicated that chronic metal exposure measured in hair changed significantly based on gender and age (p < 0.05). The levels of Cr, Fe, Ni, Si, Hg, Pb and B were significantly higher in males' hair, whereas those of Ag and Ba were greater in females' hair (p < 0.05). The results of the cognitive TMT test were significantly different between gender and age groups (p < 0.05). Moreover, results revealed that As, Hg, Mn, and Pb levels in hair were significantly associated with poorer participants' performance scores in the TMT test (p < 0.05). Age, gender, cigarette smoking, water-pipe smoking, traffic density in the area of residence, and dental amalgam filling were significant factors affecting the TMT test scores. The results suggest that chronic exposure to metals has detrimental effects on attention, executive function, mental flexibility and cognitive efficiency.

Humans spend the largest percentage of their time in indoor environments, approximately 90%. Therefore, it is critical to characterize exposures to air pollution in indoor environments in order to conduct risk and health impact assessments. Not all indoor environments are the same, hence their contributions to personal exposure will differ. This chapter discusses different factors that might affect exposure to air pollution indoors, including time spent indoors, the influence of outdoor air and the presence of indoor sources of pollution. These factors are also influenced by human, societal and environmental characteristics, e.g. gender, age, employment status and lifestyle. Geopolitics will also influence the contribution of indoor exposures to total exposure, since the economic development of countries affects housing stock, access to energy, employment opportunities and transport infrastructure, all relevant to exposure. Regional climatological conditions will also affect indoor and total exposure to air pollution. This chapter describes the methodology for determining the contribution of indoor environments to total exposure and doses of air pollution. Factors relevant to exposure in indoor environments are discussed, including exposures in developing countries and for sensitive populations.

Dementia is arguably the most pressing public health challenge of our age. Since dementia does not have a cure, identifying risk factors that can be controlled has become paramount to reduce the personal, societal and economic burden of dementia. The relationship between exposure to air pollution and effects on cognitive function, cognitive decline and dementia has stimulated increasing scientific interest in the past few years. This review of the literature critically examines the available epidemiological evidence of associations between exposure to ambient air pollutants, cognitive performance, acceleration of cognitive decline, risk of developing dementia, neuroimaging and neurological biomarker studies, following Bradford Hill guidelines for causality.The evidence reviewed has been consistent in reporting associations between chronic exposure to air pollution and reduced global cognition, as well as impairment in specific cognitive domains including visuo-spatial abilities. Cognitive decline and dementia incidence have also been consistently associated with exposure to air pollution. The neuro-imaging studies reviewed report associations between exposure to air pollution and white matter volume reduction. Other reported effects include reduction in gray matter, larger ventricular volume, and smaller corpus callosum. Findings relating to ischemic (white matter hyperintensities/silent cerebral infarcts) and hemorrhagic (cerebral microbleeds) markers of cerebral small vessel disease have been heterogeneous, as have observations on hippocampal volume and air pollution. The few studies available on neuro-inflammation tend to report associations with exposure to air pollution.Several effect modifiers have been suggested in the literature, but more replication studies are required. Traditional confounding factors have been controlled or adjusted for in most of the reviewed studies. Additional confounding factors have also been considered, but the inclusion of these has varied among the different studies. Despite all the efforts to adjust for confounding factors, residual confounding cannot be completely ruled out, especially since the factors affecting cognition and dementia are not yet fully understood.The available evidence meets many of the Bradford Hill guidelines for causality. The reported associations between a range of air pollutants and effects on cognitive function in older people, including the acceleration of cognitive decline and the induction of dementia, are likely to be causal in nature.However, the diversity of study designs, air pollutants and endpoints examined precludes the attribution of these adverse effects to a single class of pollutant and makes meta-analysis inappropriate.

The physical properties of indoor particles were measured with an Scanning Mobility Particle Sizer (SMPS) system (14.6–850 nm), an Aerodynamic Particle Sizer (APS, 0.54–18 μm) and an Hygroscopic Tandem Differential Mobility Analyzer (H-TDMA) in an apartment located in an urban background site in Prague (Czech Republic) from 15 August to 8 September, 2014. The total particle maximum number concentration was 9.38 × 104, 1.46 × 105, 2.89 × 104, 2.25 × 105 and 1.57 × 106 particles cm−3 for particles released from vacuum cleaning, soap/W5 cleaning spray, smoking, incense burning and cooking (frying) activities, respectively. Particles emitted from cleaning activities showed unimodal number size distributions, with the majority of particles (>98.2 %) in the ultrafine size range (Dp

There has been significant rise in shisha premises in the United Kingdom with an unsubstantiated belief that shisha smoking is harmless and relatively safe. This study aimed to assess the public health situation by evaluating the extent of shisha environmental tobacco smoke (ETS) exposure among those that work in, and are customers of shisha businesses. Concentrations of several ETS pollutants such as carbon monoxide (CO) and particulate matter with a diameter of less than 2.5μm (PM2.5) in shisha premises were measured using real-time sensors inside and outside twelve shisha premises and at 5 pubs/restaurants where smoking is prohibited. Mean concentration of CO (7.3±2.4mg/m(3)) and PM2.5 (287±233μg/m(3)) inside active shisha premises was higher than concentrations measured within the vicinity of the shisha premises (CO: 0.9±0.7mg/m(3) and PM2.5: 34±14μg/m(3)) and strongly correlated (PM2.5 R=0.957). Concentrations were higher than indoor concentrations in pubs and restaurants where smoking is not permitted under UK law. The number of shisha pipes was a strong predictor of the PM2.5 concentrations. The study also assessed the risk perception within patrons and managers, with only 25% being aware of the risks associated to shisha smoking. The study identifies owners, employees and consumers within active shisha premises being exposed to concentrations of CO and PM2.5 at levels considered hazardous to human health. The results and outcome of this research serve as a basis to influence a discussion around the need of developing specific policies to protect consumers and employees of such premises.

E-waste contains valuable metals that require appropriate waste management plans. However, rudimentary e-waste processing methods are a source of heavy metals environmental pollution. This study has characterised concentrations of heavy metals in soil (n = 10), water (n = 10) and hair (n = 44) of children in areas surrounding Jakarta (Indonesia), where e-waste is being or has been conducted in the past, and in a reference unexposed site. Chronic exposure to Mn, Pb, Hg, As and Cd and its associations with attention and executive function, characterised with the Trail Making Test (TMT), along with academic performance scores was conducted using multivariate regression analysis. Models were adjusted for age, gender, parental education, environmental tobacco smoke and residential traffic. Lead (3653 ± 3355 mg/kg), cadmium (3.4 ± 0.9 mg/kg) and mercury (15.2 ± 28.5 mg/kg) concentrations from soil and manganese concentrations in water (1.43 ± 0.64 mg/L) in the exposed sites were higher than current regulations. Heavy metal concentrations in hair of children living near e-waste facilities was higher than for children living in non-exposed areas (Pb: 0.155 ± 0.187 vs 0.0729 ± 0.08 mg/g; Mn: 0.130 ± 0.212 vs 0.018 ± 0.045 mg/g; Hg: 0.008 ± 0.0042 vs 0.002 ± 0.0011 mg/g) suggesting chronic exposure to heavy metals. Manganese exposure was associated with worse cognitive performance in the domains of attention (TMT-A score: 66 s, 95% CI 0.09, 132), executive function (TMT-B score: 105 s, 95% CI 11.5, 198) and social sciences (−29%, 95% CI −54, −4.7) (per unit of Mn in hair mg/g). These results suggest that informal e-waste activities contribute to local heavy metal soil contamination, and could be an important source of metal exposure to children living in the vicinity of these facilities with putative impacts on their cognitive performance. E-waste management regulation and remediation programmes should be implemented to reduce environmental pollution and associated health effects.

The spatial model development of particle distribution are necessary for studying the chronic health impacts of particulate air pollution due to residential wood- burning. The spatial variability o...

Machine learning techniques (MLTs) offer great power in analyzing complex data sets and have not previously been applied to non-occupational pollutant exposure. MLT models that can predict personal exposure to benzene have been developed and compared with a standard model using a linear regression approach (GLM). The models were tested against independent data sets obtained from three personal exposure measurement campaigns. A correlation-based feature subset (CFS) selection algorithm identified a reduced attribute set, with common attributes grouped under the use of paints in homes, upholstery materials, space heating, and environmental tobacco smoke as the attributes suitable to predict the personal exposure to benzene. Personal exposure was categorized as low, medium, and high, and for big data sets, both the GLM and MLTs show high variability in performance to correctly classify greater than 90 percentile concentrations, but the MLT models have a higher score when accounting for divergence of incorrectly classified cases. Overall, the MLTs perform at least as well as the GLM and avoid the need to input microenvironment concentrations.

The aim of this study was to investigate environmental and lifestyle factors affecting exposure to PAHs in the general population in a large city of the Middle East (Tehran) by measuring urinary monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs) and establishing relationships between PAHs exposure and related factors. Urine samples were collected from 222 randomly chosen subjects who were living in the urban area of Tehran, Iran. Subjects were required to complete a detailed questionnaire aimed to document their personal and sociodemographic information, activities, cooking-related appliances, smoking history/exposure, and consumed foodstuff. Identification and quantification of six OH-PAHs was carried out using a gas chromatography with mass spectrometry (GC-MS). The geometric means for 1-OHP, 1-NAP, 2-NAP, 2-FLU, 9-FLU, and 9-PHE for whole population study were 310, 1220, 3070, 530, 330, and 130 ng/g creatinine, respectively. The two naphthalene metabolites contributed on average 77% of the total concentration of six measured OH-PAHs, followed by the 2-FLU, 1-OHP, 9-FLU, and 9-PHE. The most important predictors of urinary PAHs were consumption of grilled/barbecued foods, smoking, and exposure to environmental tobacco smoking. Water pipe smoking was linked to urinary OH-PAH metabolite in a dose-response function. Residential traffic was also related with OH-PAH metabolite concentrations. Other factors including gender, age, exposure to common house insecticides, open burning, and candle burning were found to be statistically associated with the urinary levels of some OH-PAHs. High exposure to PAHs among general population in Middle Eastern large cities and its associated health implications calls for public health measures to reduce PAHs exposure.

Urban ambient aerosols have been of much concern in recent decades due to their effects upon both atmospheric processes and human health. This study aimed to apportion the sources of submicron particles measured at an urban background area in London and to identify which sources are most responsible for particles deposited in the human lung. Particle number size distributions (PNSD) measured by a Scanning Mobility Particle Sizer (TSI, USA), covering the size range of 16.5–604 nm at the London North Kensington background sampling site during 2012 were used in a Positive Matrix Factorization (PMF) model to apportion to six dominant sources of particles. These included local traffic emissions (26.6% by number), aged traffic emissions (29.9%), urban accumulation mode (28.3%), nucleation (6.5%), inorganic secondary aerosol (1.7%) and mixed secondary aerosol (6.9%). Based on the ICRP model, the total deposition efficiencies of submicron particles for the aforementioned sources in the human respiratory tract were 0.57, 0.41, 0.24, 0.62, 0.24 and 0.24, respectively. In terms of source apportionment of particles deposited in the lung, traffic emissions represent the main source of particles deposited by number in both the regional and total lung, accounting for 59 to 71% of total deposited particles, followed by regional accumulation mode (17%) and nucleation (10%) particles. Secondary aerosols only account for 5.1% of total deposited particles by number, but they represent the main source of particles deposited in the lung expressed as surface area (44.6%) and volume (72.3%) of total deposition. The urban accumulation mode contributes 27.3% and 17.3% of total deposited particles by surface area and volume, while traffic emissions contribute 26.6% and 9.7%, respectively. Nucleation contributes only 1.6% and 0.7% of total deposited particles by surface area and volume.

Hygroscopic properties are an important parameter in determining the atmospheric behaviour of aerosols and their optical properties, influencing the direct and indirect effect of aerosols upon climate. As a result, particle hygroscopicity has received much attention with a rapid increase of publications in recent years. Likewise, hygroscopicity is an important characteristic influencing the deposition efficiency of particles in the human respiratory tract by affecting the particle size. The object of this study is to review the existing knowledge on the hygroscopic growth factor (Gf) of atmospheric submicron particles and its influence on the lung deposition calculation. The study briefly reviews first the Gf values of particles generated from various sources, including nucleation, traffic emissions and biomass burning, discussing the spatial and temporal variations. It then summarises Gf values of submicron particles and number fraction of each hygroscopic group measured in different ambient environments. These include marine, roadside, urban background and rural environments. The study concludes by estimating the lung deposition efficiency of ambient particles using a modified version of the International Commission on Radiological Protection (ICRP) model for hygroscopic particles. Furthermore, the effect of hygroscopicity on lung deposition efficiency of ambient particles has been estimated. The ICRP model seems to predict well the deposition efficiency (DE) values for small ambient particles in the extra-thoracic and tracheo-bronchial region, but not the alveolar region, where they are overestimated. However, for larger particles (D p > 200 nm), the ICRP model underestimates the DE values, with the extra-thoracic region the most affected of the three. Hygroscopic atmospheric particles with a small diameter (D p 200 nm) showed much higher lung deposition than hydrophobic particles.

Air pollution from diesel emissions is becoming an increased international concern, and whilst attention has been primarily focused on the automotive industry, concerns have also been raised about emissions from diesel rail vehicles. This paper reports an extensive series of measurements made at the Birmingham New Street station, a major rail interchange in the Midlands of England, with a mix of diesel and electric train movements, which is of particular concern because of the enclosed nature of the platforms. This study was undertaken in collaboration with Network Rail to better understand the environment in and around the station over a longer period to provide a more detailed analysis of the complex environment at the station. The station environment has been considered in terms of the European Union (EU) and Department of Environment, Food and Rural Affairs (DEFRA) limits as part of the monitoring methodology, but it should be noted that these limits do not apply in this environment as the Management of Health and Safety at Work Regulation 1999 and the Control of Substances Hazardous to Health Regulations 2002 are applicable. The monitoring campaign consisted of diffusion tube measurements to measure nitrogen dioxide at a large number of different locations throughout and around the station. These were followed by detailed measurements of oxides of nitrogen, particulate matter, carbon dioxide and black carbon (a diesel tracer) at a smaller number of sites at the platform level. The results are analysed to give concentrations over a wide variety of time scales, and long- and short-term averages. The effects of ambient wind conditions and individual train movements are also considered. Recommendations are made for possible remedial measures and for future work to more fully understand the physical mechanisms involved.

Vapour and particle-associated concentrations of 15 polycyclic aromatic hydrocarbons (PAH) and 11 PAH quinones have been measured in winter and summer campaigns at the rural site, Weybourne in eastern England. Concentrations of individual PAH are relatively smaller than average concentrations measured previously at urban sites in the UK. The concentrations of PAH of the air masses originating from southern England and mainland UK are significantly larger than those from Eastern Europe and the North Atlantic, while quinone to parent PAH ratios show an inverse behaviour, being highest in the more aged North Atlantic polar air masses. While concentrations of 1,2-naphthoquinone decline from winter to summer, those of 1,4-naphthoquinone and anthraquinone increase suggesting a photochemical formation pathway. A comparison of congener concentration profiles measured at Weybourne with those from an urban source area (Birmingham) reveals differential losses at the rural site, especially evident in fluoranthene : pyrene ratios and consistent with the known rates of vapour phase reactions of 3 and 4 ring compounds with hydroxyl radical. The ratios of quinones to their parent PAH at Weybourne are greater than those in the urban source area indicating either more rapid loss processes for PAH, or formation of quinones during advection of the air mass, or probably both.

Polycyclic aromatic hydrocarbons (PAH) are often measured in studies of atmospheric chemistry or health effects of air pollution, due to their known human carcinogenicity. In recent years, PAH quinone derivatives have also become a focus of interest, primarily because they can contribute to oxidative stress. This work reports concentrations of 17 PAH and 15 quinones measured in air samples collected at a trafficked roadside. Data are presented for four compounds not previously reported in ambient air: 2-methyl-1,4-naphthoquinone, 2,6-di-tert-butyl-1,4-benzoquinone, methyl-1,4-benzoquinone and 2,3- dimethylanthraquinone, and a large vapour phase component is measured, not analysed in most earlier studies. Analyses are reported also for SRM 1649a and 1649b, including many compounds (8 for SRM 1649a and 12 for SRM 1649b) for which concentrations have not previously been reported. This work assesses the vapour/particle phase distribution of PAHs and quinones in relation to their molecular weight, vapour pressure, polarity and Henry's Law constant, finding that both molecular weight and vapour pressure (which are correlated) are good predictors of the partitioning.

The sources of polycyclic aromatic hydrocarbon (PAH) in various environmental media have commonly been identified based on the ratios of concentrations of selected PAH congeners. These ratios are applicable to various environmental media and distinguish between sources originating from vehicular emissions, petroleum products, petroleum combustion, coal and biomass burning. In this study an evaluation of PAH diagnostic ratios is provided for vapour and particulate phase samples collected simultaneously at well defined roadside and suburban sites in Birmingham, UK. It focuses on 14 PAH and 11 quinone compounds which were measured at both sites to obtain information upon traffic emissions (and subsequently a PAH congener traffic profile) and to evaluate the validity of PAH diagnostic ratios. The results suggest that PAH ratios of the low molecular weight compounds are less stable and more susceptible to atmospheric processing, indicating the importance of determining PAH ratio threshold values based on well defined samples. Quinone to parent-PAH ratios were also examined to assess the potential reactivity of PAH compounds, where the results suggest that significant atmospheric processing occurs during transport, altering the ratios between both sites, in a manner related to the relative reactivity of different PAH congeners.

It has long been known that cooking can create high concentrations of aerosol indoors. Increasingly, it is now being reported that cooking aerosol is also a significant component of outdoor particulate matter. As yet, the health consequences are unquantified, but the presence of well known chemical carcinogens is a clear indication that cooking aerosol cannot be benign. This review is concerned with current knowledge of the mass concentrations, size distribution and chemical composition of aerosol generated from typical styles of cooking as reported in the literature. It is found that cooking can generate both appreciable masses of aerosol at least within the area where the cooking takes place, that particle sizes are largely within the respirable size range and that major groups of chemical compounds which have been used to characterise cooking aerosol include alkanes, fatty acids, dicarboxylic acids, lactones, polycyclic aromatic hydrocarbons, alkanones and sterols. Measured data, cooking emission profiles and source apportionment methods are briefly reviewed.

The fraction of outdoor aerosol that penetrates into indoor environments plays an important role in determining the contribution of outdoor particles to the total lung dose of particles in human exposure. The objective of this study was to investigate the physical processes affecting migration of outdoor traffic particles into indoor environments. Particle number size distributions were measured by a fast mobility particle sizer system in both indoor and outdoor environments of a house located in close proximity to a busy street in Bologna (Italy) in the period February–April 2012. Indoor to outdoor (I/O) ratios for submicron particle number concentrations showed strong dependence on particle size and meteorological conditions. The loss rates of particles due to deposition, coagulation, and evaporation were determined using dynamic mass balance and coagulation models. Higher loss rates were found for small particles (nucleation and Aitken mode) indoors than for larger particles (accumulation mode). The coagulation and evaporation processes made a significant contribution to the loss of traffic nanoparticles indoors, especially during the day time. Application of positive matrix factorization to the indoor and outdoor particle size distributions showed a substantial loss of traffic-generated nucleation mode particles in the indoor environment, with evaporation playing a major role. Copyright © 2017 American Association for Aerosol Research

Gasoline direct injection (GDI) engines are increasingly prevalent in the global vehicle fleet. Particulate matter emissions from GDI engines are elevated compared to conventional gasoline engines. The pulmonary effects of these higher particulate emissions are unclear. This study investigated the pulmonary responses induced by GDI engine exhaust using an ex vivo model. The physiochemical properties of GDI engine exhaust were assessed. Precision cut lung slices were prepared using Balb/c mice to evaluate the pulmonary response induced by one-hour exposure to engine-out exhaust from a laboratory GDI engine operated at conditions equivalent to vehicle highway cruise conditions. Lung slices were exposed at an air-liquid interface using an electrostatic aerosol in vitro exposure system. Particulate and gaseous exhaust was fractionated to contrast mRNA production related to polycyclic aromatic hydrocarbon (PAH) metabolism and oxidative stress. Exposure to GDI engine exhaust upregulated genes involved in PAH metabolism, including Cyp1a1 (2.71, SE=0.22), and Cyp1b1 (3.24, SE=0.12) compared to HEPA filtered air (p

Both the World Health Organization and the UK Expert Panel on Air Quality Standards (EPAQS) have considered benzo(a)pyrene (BaP) as a marker of the carcinogenic potency of the polycyclic aromatic hydrocarbons (PAH) mixture, when recommending their respective guidelines for PAHs in outdoor air. The aim of this research is to compare the concentrations and relative abundance of individual PAH and their contribution to the overall carcinogenic potential of the PAH mixture in indoor and outdoor environments to assess the suitability of the UK air quality standard derived for outdoor air for use as a guideline for indoor environments. Samples were collected onto filters using active sampling in different indoor and outdoor microenvironments. The ratio of individual compounds to BaP, the BaP equivalent concentrations and the percentage contribution of each individual compound to the total carcinogenic potential of the PAH mixture were calculated. Mean concentrations were generally lower indoors (BaP=0.10 ng/m3) than outdoors (BaP=0.19 ng/m3), with the exception of indoor environments with wood burners (BaP=2.4 ng/m3) or ETS (BaP=0.6 ng/m3). The ratio of individual PAHs to BaP showed no significant differences between indoors (e.g. DahA/BaP=0.27) and outdoors (DahA/BaP=0.31). The relative contribution of BaP to the PAH overall carcinogenic potency is similar indoors (49%), outdoors (54%) and in the smelter environment (48%) used by EPAQS to derive the UK Air Quality Standard for ambient air. These results suggest the suitability of BaP as a marker for the carcinogenic potential of the PAH mixture irrespective of the environment. Despite small differences in PAH mixture composition indoors and outdoors, the level of protection afforded by the present EPAQS standard is likely to be similar whether it is applied to indoor or outdoor air. Keywords: Air quality standards, Benzo(a)pyrene, Carcinogenic potential, Marker, Polycyclic aromatic hydrocarbon

This work assesses the effects caused by tropospheric ozone on citric crops in "La Plana de Castellon", a western Mediterranean area rich in orange orchards. Passive ozone samplers were used as an alternative tool to monitor the ozone levels, to assess the effects of ozone levels on citrus crops, and to estimate the percentage of losses in harvest crops. Measurements were taken during the 3-month periods of higher ozone levels in the summers of 2001, 2002 and 2003. Measurement campaigns were divided into sampling periods of 1 week. Twenty samples were collected during each sampling period to cover an area of 8000 km2. Summer weekly ozone levels ranged between 40-44 μg/m3 in 2001, 54-70 μg/m3 in 2002 and 34-44 μg/m3 in 2003. To assess the effects on orange and lemon trees, a linear equation which described the relationship between ozone concentrations and citrus trees yields was employed. There was an estimated 8% reduction in orange and 11.5% reduction in lemon yields in the year 2003 due to the average ozone levels in the year 2001, a 10% reduction in orange and 14.2% reduction in lemon yield in the year 2004, due to the average ozone levels in the year 2002 and an estimated 7% reduction in orange and 9.8% reduction in lemon yield in the year 2005 due to the average ozone levels in the year 2003. These yield losses may negatively affect the local economy of the area. Passive samplers also proved to be a useful tool for assessing the response of citrus trees to environmental photochemical stress due to tropospheric ozone. © 2007 Elsevier B.V. All rights reserved.

Due to the need to better characterise the ultrafine particles fraction and related personal exposure, several impactors have been developed to enable the collection of ultrafine particles (320 nm, whereas for particle diameters

This paper presents the development, laboratory evaluation, and field tests of a personal respirable particulate sampler (PRPS). The PRPS is designed as a personal sampling system to collect particulate matter (PM0.5, PM1.0, PM2.5, PM4.5, and PM10) and gaseous pollutants, including O3, SO2, and NO2. It operates at a flow rate of 5.0 LPM and consists of five selectable impaction stages (with cutpoints of 10, 4.5, 2.5, 1.0, and 0.5 μm), a backup filter, and two diffusion passive samplers. In each impaction stage, particles are collected onto a polyurethane foam (PUF) substrate. This substrate, using no adhesive, was shown to have minimum particle bounce and re-entrainment. A backup 37 mm Teflon membrane filter is used downstream to collect particles smaller than the cutoff diameter of the final impaction stage. The impaction stage cutpoints were characterized in the laboratory using artificially generated polydisperse aerosols. Particle losses for each stage were found to be acceptably low. The performance of the PRPS was also compared with that of a collocated micro-orifice cascade impactor (MOI) and real-time particle sizing instruments (SMPS/APS) in laboratory experiments using artificially generated particles. The size distributions measured by the PRPS were found to be much closer to those measured by the real-time particle sizing instruments than to those measured by the MOI. A field PM intercomparison study was also conducted using the PRPS and three reference samplers, the Harvard Impactor (HI), the USEPA PM2.5 Well Impactor Ninety Six (WINS), and the Harvard Personal Environmental Monitor (Harvard PEM) sampler. The PM10, PM2.5, and sulfate concentrations measured by PRPS were in a very good agreement with those obtained from the reference samplers.

Despite the use of cerium oxide nanoparticles (nCe) in some regions as a diesel fuel additive, the physicochemical properties of the resulting exhaust particles in the ambient atmosphere are not well known. The mixing state of ceria with other exhaust particles is one such physicochemical property that has been shown to potentially affect ecosystem/human health. In this study, cerium-containing particles associated with an nCe additive were collected in the laboratory and in Newcastle-upon-Tyne, UK where the local bus fleet uses the Envirox nCe additive. Electron microscopy of laboratory-generated exhaust samples indicated both individual ceria and soot particles (external mixture) and ceria contained within soot agglomerations (internal mixture). Low ambient concentrations prevented quantification of the ceria particle mixing state in the atmosphere; therefore, a multicomponent sectional aerosol dynamic model was used to predict the size, chemical composition, and mixing state of ceria particles as a function of distance from an idealized roadway. Model simulations predicted that most ceria particles remain nonmixed in the ambient atmosphere (300 m downwind from the roadway) due to slow coagulation, with the mixing rate most sensitive to the ceria content of emitted nuclei-mode particles and the particle concentration upwind of the road. Although microscopy analysis showed both external and internal mixtures of ceria and soot in freshly emitted particles, the ambient mass concentration, and size distribution of ceria particles predicted by the model was insensitive to the emitted mixing state.Copyright 2015 American Association for Aerosol Research

Volatile organic compounds (VOCs) are ubiquitous pollutants known to be present in both indoor and outdoor air arising from various sources. Indoor exposure has increasingly become a major cause of concern due to the effects that such pollutants can have on health. Benzene, along with toluene, is one of the main components of the VOC mixture and is a known carcinogen due to its genotoxic effects. The aim of this study was to test the feasibility of an in vitro model to study the short-term effects of exposure of lung cells to airborne benzene. We studied the effects of exposure on DNA and the production of reactive oxygen species (ROS) in A549 cells, exposed to various concentrations of benzene (0.03; 0.1; 0.3 ppm) in gaseous form using a custom designed cell exposure chamber. Results showed a concentration-dependent increase of DNA breaks and an increase of ROS production, confirming the feasibility of the experimental procedure and validating the model for further in vitro studies of exposure to other VOCs.