Polycycl. Aromatic Hydrocarbon Exposure of Children in Typical Household Coal Combustion Environments: Seasonal Variations, Sources, and Carcinogenic Risks.

Personal inhalation exposure samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) for 126 selected volunteers during heating and non-heating seasons in a typical northern Chinese city, Taiyuan. Measured personal PAH exposure levels for the urban residents in the heating and non-heating seasons were 690 (540-1051) and 404 (266-544) ng/m(3) , respectively, while, for the rural residents, they were 770 (504-1071) and 312 (201-412) ng/m(3) , respectively. Thus, rural residents are exposed to lower PAH contamination in comparison with the urban residents in the non-heating seasons. In the heating season, personal PAH inhalation exposure levels were comparable between the urban and rural residents, in part owing to the large rate of residential solid fuel consumption in the rural area for household cooking and heating. The estimated incremental lifetime cancer risks (ILCR) due to PAH exposure in Taiyuan were 3.36×10(-5) and 2.39×10(-5) for the rural and urban residents, respectively, significantly higher than the literature-reported national average level, suggesting an urgent need of PAH pollution control to protect human health.

Nitropolycyclic aromatic hydrocarbon (NPAH) emissions from the combustion of household solid fuel may cause great harm to public health. Children are one of the most susceptible population groups at risk of indoor air pollutants due to their immature respiratory and immune systems. In this study, a primary school using household coal combustion for heating in winter was selected and forty participants were randomly recruited among schoolchildren. Fine particulate matter samples were collected by both individual portable samplers and fixed middle‐flow samplers during the heating and nonheating seasons. The NPAH concentrations in PM2.5 samples were analyzed by a gas chromatograph coupled to a mass spectrometer. Potential sources of NPAHs were identified by NPAH ratios as well as principal component analysis. Lung function of children was tested by an electronic spirometer. The relationship between NPAH exposure level and children’s lung function was studied. Finally, the cancer risk caused by NPAH inhalation was assessed. The results showed significantly higher individual NPAH exposure level in heating season (0.901 ± 0.396 ng·m-3) than that in nonheating season (0.094 ± 0.107 ng·m-3). Coal/biomass combustion and secondary formation were the potential NPAH sources in heating season. Significantly lower lung function of children was also found in heating season compared with that in nonheating season. As a result of the Monte Carlo simulation, the averaged incremental lifetime cancer risk (ILCR) values from the inhalation of NPAHs in the heating and nonheating seasons were 3.50 × 10−8 and 2.13 × 10−8, respectively. Our research revealed the association between NPAH exposure and children’s lung function and confirmed the adverse effect of indoor coal combustion. The results also indicated that further control strategies on indoor coal combustion are needed to reduce the risk of NPAH exposure and protect children’s health.

Assessment of human indoor exposure to PAHs during the heating and non-heating season: Role of window films as passive air samplers

The occurrence and fate of PAHs over multiple years in a wastewater treatment plant of Harbin, Northeast China

Composite of PAH-degrading endophytic bacteria reduces contamination and health risks caused by PAHs in vegetables

Atmospheric behaviors of particulate-bound polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons in Beijing, China from 2004 to 2010

Polycyclic aromatic hydrocarbons (PAHs) were determined in total suspended particles(TSP) sampled from 7 different typical cities in Shandong province, China. The sum of sixteen EPA priority PAHs concentrations ranged from 56.22 to 612.93 ng per cubic meter in heating season and from 7.18 to 127.79 ng per cubic meter in nonheating season in Shandong region. The levels of PAHs concentration background in Shandong province Changdao was also higher than others. All the PAH species were detected in nonheating season but DahA and BghiP were not detected in heating season in Changdao background. In spite of PAHs concentrations background in Changdao, the ratio of BaP to the sum of sixteen PAHs equivalent concentration in Changdao in heating season was the highest and the contribution proportion was up to 71.94 percent. The regression equations with very good correlation ships were set up including concentrations of BaP, TSP and sum of sixteen PAHs in Shandong province in different seasons, the correlation coefficient square respectively 0.996 and 0.979, which were used to evaluate the PAHs health risk in atmospheric particles.

<p>In this work, the exposure of people, through their diet, to polycyclic aromatic hydrocarbons (PAHs) has been assessed for the urban, rural, and general populations in Syria. The food categories consumed have been divided into major groups, and the health risk assessment on dietary exposure of PAHs determined in each food category. For this purpose, two approaches were used: incremental lifetime cancer risk (ILCR) and margin of exposure approach (MOE). The results showed that each of the following food categories: oils and fats, meat and meat products, vegetables, and cereals dominantly contribute in the dietary exposure of PAHs. Also their MOE values are the lowest. Additionally, they have higher ILCR values. Therefore, these groups are a main risk source to health. On the other hand, the dietary exposure of PAHs in each of urban, rural and general populations was of low health concern, whereas their ILCR values reached to 10E-05 in total food categories, nevertheless it remains lower than serious risk level (ILCR>10E-04). This work is the first study that is dealing with dietary exposure of PAHs and their health risk assessment in Syria.</p>

In urban North China, nitrate () is a primary contributor to haze formation. So far, the production processes and source apportionments of atmospheric during the heating season (i.e. the wintertime) have not yet been well understood. This study determined δ15N–, δ18O–, and Δ17O– of aerosol samples to compare the potential sources and formation pathways of atmospheric during heating (November to March) and non-heating (April to May) seasons. Combining stable isotope composition with the MixSIAR model based on Δ17O– showed that NO3 + DMS/HC (dimethyl sulfate/hydrocarbon) pathway was the dominant process of atmospheric nitrate formation during the heating season (mean = 52.88 ± 16.11%). During the non-heating season, the contributions of NO3 + DMS/HC (mean = 37.89 ± 13.57%) and N2O5 + H2O (mean = 35.24 ± 3.75%) pathways were comparable. We found that Δ17O– was negatively correlated with wind speed and positively correlated with relative humidity during the heating season, possibly associated with the sources and production of atmospheric . In specific, in a dust storm event, the very low Δ17O– is likely associated with particles from land surface. Under the premise of considering 15N fractionation, the constraint-based on δ15N– illustrated that coal combustion was the major source of NO x emission during the heating season, and the relative contribution of coal combustion decreased rapidly from the heating season (mean = 42.56 ± 15.50%) to the non-heating season (mean = 21.86 ± 4.91%). Conversely, the proportion of NOx emitted by soil microbes rose significantly from the heating (mean = 9.67 ± 5.99%) to non-heating season (mean = 24.02 ± 11.65%). This study revealed differences in the sources and formation processes of atmospheric during the heating and non-heating seasons, which are of significance to atmospheric nitrogen oxide/nitrate pollution mitigation.

Polycyclic aromatic hydrocarbons (PAHs) are considered to be major air pollutants with a strong negative influence on human health. Many of them are toxic with high carcinogenic potential. Children and school staff spend a significant portion of daytime at schools, mostly indoors. Therefore, the hypothesis can be made that air quality significantly impacts their health. A health risk assessment, performed by calculating Incremental lifetime cancer risk (ILCR), was conducted in the framework of this study. Indoor and outdoor PAHs concentrations were measured in typical Serbian primary school. Total suspended particles (TSP) and gas-phase PAHs from the air were collected both inside the school building and in the outside school environment. Average indoor and outdoor PAHs concentrations were used to calculate benzo[a]pyrene equivalent (BaPeq) concentration. A significantly higher BaPeq was observed in the gas-phase than in the TSP, due to a high amount of low molecular PAHs present in the gas-phase. The measured BaPeq concentration values were fitted to the appropriate mathematical distribution and used as an input parameter for stochastic ILCR modeling. Different body weight and inhalation rate distributions were used for sampling during ILCR calculations. The performed sensitivity analysis showed that the two different recommended values of cancer slope factor had a major impact on the ILCR values. Based on this, it was decided to perform simulations using cancer slope factors for individual PAHs. The obtained ILCR values for both children and adults were greater than the allowed level, indicating high potential lung cancer risk. It may be concluded that it is necessary to improve indoor air quality in schools applying measures for lowering TSP PAHs with high carcinogenic potential.

Health exposure of users of indoor sports centers related to the physico-chemical properties of particulate matter

PM2.5-bound polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons inside and outside a primary school classroom in Beijing: Concentration, composition, and inhalation cancer risk

Polycyclic aromatic hydrocarbons in dustfall in Tianjin, China

The polycyclic aromatic hydrocarbons (PAHs) are considered as an important class of organic pollutants in the urban atmosphere to pose serious health hazards. A comprehensive study was conducted during the dry seasons of 2017–2018 to understand the impacts of local sources, meteorology, boundary layer dynamics, and long-range transport, on the size-specific particulate PAHs (Coarse: 10–2.1 µm; Superfine: 2.1–1.1 µm; Accumulation: 1.1–0.4 µm and Ultrafine: < 0.4 µm). Samples were collected over Kolkata (22.33°N and 88.20°E), a megacity of the lower Indo-Gangetic Plain (IGP). Wintertime distributions of all PAHs were exclusively unimodal with their maximum abundance in accumulation mode, whereas the 4,5 and 6-ring PAHs showed additional coarse mode peaks during post-monsoon and pre-monsoon. The Concentration Weighted Trajectory model has identified the middle IGP and the Eastern Ghats as the potent PAH source regions for the receptor site. Meteorology significantly influenced, in minimizing the contributions of transported PAHs from biomass burning regions of Eastern Ghats during pre-monsoon. On the contrary, meteorology favored the PAHs accumulation from local emissions and long-range transport during winter and post-monsoon. Source apportionment by positive matrix factorization model identified unburned petroleum, incineration, fossil fuel and coal burning as possible major sources of size-specific PAHs. Additionally, based on benzo(a)pyrene equivalent concentrations, the incremental lifetime cancer risk (ILCR) values were estimated for four human age groups. In general, ILCR values were influenced by the accumulation mode, and they were highest for all size ranges during winter. The estimated upper limit of ILCR (9.26 × 10–6) exceeding the carcinogenic benchmark level (1 × 10–6), draws attention towards the adverse impacts of wintertime ultrafine PAHs on human health in Kolkata, where poor air quality is already a major concern.

Time trends of polycyclic aromatic hydrocarbon exposure in New York city from 2001 to 2012: Assessed by repeat air and urine samples