Springer Science and Business Media LLC

Air pollution dispersion modeling is one of the methods for the ambient air quality assessment. The mathematical models are widely used tools for predicting air pollution and accurately assessing the spatial distribution of air pollutants in the city. Road transport is one of the main sources of pollution affecting air quality in urban areas, and nitrogen dioxide is considered to be one of the most common with traffic emission-related pollutant, which concentrations are strongly correlated to the distance from the roadways. The study aim was to determine the dispersion of nitrogen dioxide (NO2) concentration and to estimate the inter-seasonal differences in these concentrations at different sites (rural, urban, traffic) using a ADMS-Urban model and measurements in Kaunas city. For the modeling of nitrogen dioxide pollution, the year 2011 was selected. Average concentrations of nitrogen dioxide for the winter, summer, and intermediate spring seasons were modeled. Nitrogen dioxide concentrations calculated by model have been verified against 41 Ogawa passive sampling results. The modeling results showed that the highest average seasonal NO2 concentration was modeled in the winter season (21.79 μg/m3), while the lowest concentration was determined in summer (12.28 μg/m3). Correlation coefficient between modeled NO2 concentrations using the ADMS-Urban model and measured by Ogawa passive samplers was significantly high for all seasons and confirmed the generally good performance of the model.

Có những cấu hình không gian nhất định trong các thành phố tạo ra các khu vực có thông gió giảm, nơi mà ô nhiễm không khí có thể đạt tới mức độ nguy hiểm. Mặc dù hình thức đô thị đã được chỉ ra là một yếu tố ảnh hưởng đến ô nhiễm không khí, nhưng vai trò của nó trong việc tích tụ các hợp chất hữu cơ bay hơi chưa được đánh giá đầy đủ thông qua các phép đo thực địa. Để nghiên cứu tác động của hình thái đô thị đối với mức độ ô nhiễm không khí, chúng tôi đã đo nồng độ benzene, toluene, ethylbenzene và xylenes (BTEX) tại 44 địa điểm khác nhau trong thành phố, sử dụng bộ thu thập thụ động khuếch tán Radiello® trong một chiến dịch kéo dài 1 tuần. Công việc này trình bày một phương pháp nhằm lập bản đồ thành phố theo các khu vực với mức độ phân tán khí quyển khác nhau bằng cách phân tích tỷ lệ BTEX trong không khí xung quanh. Phương pháp áp dụng cho một thành phố ven biển (đặc trưng bởi các kiểu gió đồng nhất) đã phát hiện sự tồn tại của hai khu vực được phân biệt rõ ràng. Trong một khu vực, nồng độ benzene trung bình cao hơn 3.26 lần so với khu vực kia. Tuy nhiên, nồng độ trung bình của phần còn lại của BTEX gần như không khác nhau giữa hai khu vực. Những phát hiện này cho thấy các chất ô nhiễm phân hủy chậm (ví dụ: benzene) tập trung ở các khu vực thông gió kém, trong khi các chất ô nhiễm phân hủy nhanh không cho thấy sự tích tụ. Các kết luận của nghiên cứu này có thể đặc biệt hữu ích trong việc thiết kế các đánh giá về tiếp xúc cá nhân, tối ưu hóa hình thái đô thị và cải thiện vị trí của các trạm giám sát chất lượng không khí.

Volatile organic compounds (VOCs) are generated from animal rendering facilities, some of which are malodorous, while others are considered hazardous. Odor annoyance potential, possible carcinogenic risks, and toxic effects due to VOC emissions from a rendering plant unit in Southwest Greece were evaluated for the general population residing in the near vicinity. Nine air samples were collected from the facilities of an integrated rendering plant and the surrounding area, over a 9-month period. Volatile compounds were absorbed onto solid sorbents containing Tenax TA/Sulficarb via active sampling and analyzed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Sixty-three organic compounds, mainly volatile fatty acids, aldehydes, aromatic, and sulfur compounds, were quantified, in concentrations ranging from < 0.01 to 210 μg m−3. The compounds contributing most to odor nuisance were butanoic acid, dimethyl trisulfide, and octanal, exceeding their odor threshold by up to 24, 36, and 117 times, respectively. Cancer and non-cancer risks were determined by a probabilistic risk assessment method. The cumulative lifetime cancer risk for the general population was calculated to be on average 10 times higher than the acceptable risk (one-in-a-million). The cumulative mean hazard quotient was 3.3 and its 95th percentile was 4.0, indicating a high risk of adverse health effects. Control measures to prevent the generation of the VOCs responsible for both odor nuisance and potential adverse health effects should be adopted.

A cross-sectional survey study was conducted in Nanchang University between April and May of 2014, with a total of 528 respondents (response rate = 96 %) to examine public perception regarding the current air pollution and its effect on public health. Approximately 57 % of the respondents perceived that the air quality in Nanchang was fair. Over 93 % of respondents understood that there is an association between air pollution and human health. Over 95 % of respondents believe more money and action should be allocated toward future efforts to improve air quality of Nanchang. Almost all respondents (>97 %) agreed that the improvement of air quality is also the responsibility and obligation of every citizen. This study clearly shows that there exists positive perception and strong support from Nanchang public on air quality improvement, which could be valuable and used to influence local government for stricter regulations for improving air quality and healthy environment in future.

Recent investigations suggest that the accumulation of polluted aerosols at mountain sites of the Indian Himalaya potentially may accelerate the seasonal warming. In view of the importance of aerosols, the present study was carried out over Mohal (1154 m) during April 2006 to March 2010. The investigation of the optical properties of aerosols such as single-scattering albedo (SSA), asymmetry parameter (AP), and their effect on aerosol radiative forcing (ARF) from this part of India are also reported in earlier studies. However, those studies did not fully focus on the radiative effect of aerosols. In this study, we focus on this important aspect; the ARF was computed using the atmospheric radiation transfer model (RTM). The radiative properties of aerosols used in RTM are retrieved from Optical Properties of Aerosol and Cloud (OPAC) model. The seasonal highest SSA at 0.5 μm was obtained in premonsoon season (0.875 ± 0.03) and lowest in winter (0.754 ± 0.07). The seasonal highest AP at 0.5 μm was obtained in premonsoon (0.678 ± 0.01) and lowest in winter (0.654 ± 0.01). The mean (period April 2006 to March 2010) values of ARF at the surface, top of the atmosphere, and the atmosphere are estimated to be −19.1 ± 1.9, +0.5 ± 3.3, and +19.6 ± 3.7 W m−2, respectively. During the dust-laden period, this study reports strong response to atmospheric forcing; this increases the atmospheric heating rate by a factor 2.4 when compared to low aerosol-laden period. Based on review of the literature, it is found that in the northern and eastern subcontinent of India, the large decrease in surface reaching solar radiation is due to the abundance of desert dust aerosols. In the western and southern subcontinent of India, the large decrease in surface reaching solar radiation is mainly due to the abundance of anthropogenic aerosols.

To clarify the pollution sources of heavy metals in PM2.5 and the health risks posed by them in heating and non-heating seasons, 42 samples were collected in 2017 and 2018 in Taiyuan and Yuci college town, China. Elemental analysis of the PM2.5 samples through acid-dissolved plasma mass spectrometry was performed to determine the concentrations of 10 elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn). We determined the types of pollution sources by enrichment factor (EF) and principal component analysis (PCA). We performed a health risk assessment based on the US Environmental Protection Agency (EPA) guidelines and the database of the International Agency for Research on Cancer (IARC) to assess both carcinogenic and non-carcinogenic risks of the heavy metals to adults and children. The results indicate that the EF values of all 10 elements were greater than 1, suggesting anthropogenic sources in both heating and non-heating seasons. PCA revealed that the three main components were soot dust, metal smelting emission, and industrial dust. Regarding the health risks caused by the heavy metals, children were more susceptible to non-carcinogenic risks than adults, and people faced higher non-carcinogenic risks during the heating season. For carcinogenic risk, Cr has the highest risk coefficient (1.68 × 10−4), higher than the US EPA’s threshold (1.00 × 10−6). People were exposed to carcinogenic risk. The study explored specific pollution sources and explained their effect on health to assist with the development of prevention and control measures.

Severe surface ozone (SO) pollution is a major weather extreme during hot summer season in China. In previous studies, many synoptic patterns or weather types described by different meteorological variables are interconnected to use in explaining the formation of SO pollution under a determined emission of precursors. Here, we first identify the top 20 SO events which happened in North China during the summer (May–August) from 2014 to 2019. Then, an approach of anomaly-based synoptic analysis is used to establish the relationship between the anomalous synoptic pattern (ASP) and strong SO events based on four case analyses. The result showed that a strong SO event is directly associated with a near surface inversion of temperature anomalies satisfying the hydrostatic balance with geopotential anomalies at the lower troposphere. The European Centre for Medium-Range Weather Forecasts (ECMWF) model can successfully predict this ASP with lead times of 144 h for the strongest case. The advantages of this approach include its ability to visually identify the location of a SO event through pinpointing possible meteorological conditions and extend the SO forecast length by the earlier ASP detection.