Ambient particulate matter (PM) pollution has been linked to elevated mortality, especially from cardiovascular diseases. However, evidence on the effects of particulate matter pollution on cardiovascular mortality is still limited in Lanzhou, China. This research aimed to examine the associations of daily mean concentrations of ambient air pollutants (PM2.5, PMC, and PM10) and cardiovascular mortality due to overall and cause-specific diseases in Lanzhou. Data representing daily cardiovascular mortality rates, meteorological factors (daily average temperature, daily average humidity, and atmospheric pressure), and air pollutants (PM2.5, PM10, SO2, NO2) were collected from January 1, 2014, to December 31, 2017, in Lanzhou. A quasi-Poisson regression model combined with a distributed lag non-linear model (DLNM) was used to estimate the associations. Stratified analyses were also performed by different cause-specific diseases, including cerebrovascular disease (CD), ischemic heart disease (IHD), heart rhythm disturbances (HRD), and heart failure (HF). The results showed that elevated concentration of PM2.5, PMC, and PM10 had different effects on mortality of different cardiovascular diseases. Only cerebrovascular disease showed a significant positive association with elevated PM2.5. Positive associations were identified between PMC and daily mortality rates from total cardiovascular diseases, cerebrovascular diseases, and ischemic heart diseases. Besides, increased concentration of PM10 was correlated with increased death of cerebrovascular diseases and ischemic heart diseases. For cerebrovascular disease, each 10 μg/m3 increase in PM2.5 at lag4 was associated with increments of 1.22% (95% CI 0.11–2.35%). The largest significant effects for PMC on cardiovascular diseases and ischemic heart diseases were both observed at lag0, and a 10 μg/m3 increment in concentration of PMC was associated with 0.47% (95% CI 0.06–0.88%) and 0.85% (95% CI 0.18–1.52%) increases in cardiovascular mortality and ischemic heart diseases. In addition, it exhibited a lag effect on cerebrovascular mortality as well, which was most significant at lag6d, and an increase of 10 μg/m3 in PMC was associated with a 0.76% (95% CI 0.16–1.37%) increase in cerebrovascular mortality. The estimates of percentage change in daily mortality rates per 10 μg/m3 increase in PM10 were 0.52% (95% CI 0.05–1.02%) for cerebrovascular disease at lag6 and 0.53% (95% CI 0.01–1.05%) for ischemic heart disease at lag0, respectively. Our study suggests that elevated concentration of atmospheric PM (PM2.5, PMC, and PM10) in Lanzhou is associated with increased mortality of cardiovascular diseases and that the health effect of elevated concentration of PM2.5 is more significant than that of PMC and PM10.
The odour emission characteristics of 22 recreational rivers in Nanjing were investigated and analysed. Eight odorous compounds (ammonia (NH3), hydrogen sulphide (H2S), sulphur dioxide (SO2), carbon disulphide (CS2), nitrobenzene (C6H5NO2), aniline (C6H5NH2), dimethylamine (C2H7N), and formaldehyde (HCHO)) were measured in odour emission samples collected using a custom-made emission flux hood chamber. The results showed that all odorants were detected in all monitoring rivers. NH3 was the main odorant, with emission rates ranging from 4.86 to 15.13 μg/min m2. The total odour emission rate of the Nan River, at 1 427.07 OU/s, was the highest of the all investigated rivers. H2S, NH3 and nitrobenzene were three key odour emission contributors according to their contributions to the total odour emission. A correlation analysis of the pollutants showed there was a significant positive correlation between the emission rate of NH3 and the concentration of ammonia nitrogen (NH4+-N) and total nitrogen (TN). The H2S and SO2 emission rates had a significant positive correlation with sulphides (S2?) and available sulphur (AS) in the water and sediment. The content of TN, NH4+-N, S2? and AS in the water and sediment affected the concentration of H2S, SO2 and NH3 in the emission gases. NH4+-N, S2? and AS are suggested as the key odour control indexes for reducing odours emitted from these recreational rivers. The study provides useful information for effective pollution control, especially for odour emission control for the recreational rivers of the city. It also provides a demonstrate example to show how to monitor and assess a contaminated river when odour emission and its control need to be focused on. 相似文献
In Mediterranean seas and coastal zones, rivers can be the main source of mercury (Hg). Catchment management therefore affects the load of Hg reaching the sea with surface runoff. The major freshwater inflows to the Baltic Sea consist of large rivers. However, their systems are complex and identification of factors affecting the outflow of Hg from its catchments is difficult. For this reason, a study into the impact of watershed land use and season on mercury biogeochemistry and transport in rivers was performed along two small rivers which may be considered typical of the southern Baltic region. Neither of these rivers are currently impacted by industrial effluents, thus allowing assessment of the influence of catchment terrain and season on Hg geochemistry. The study was performed between June 2008 and May 2009 at 13 sampling points situated at different terrain types within the catchments (forest, wetland, agriculture and urban). Hg analyses were conducted by CVAFS. Arable land erosion was found to be an important source of Hg to the aquatic system, similar to urban areas. Furthermore, inflows of untreated storm water discharge resulted in a fivefold increase of Hg concentration in the rivers. The highest Hg concentration in the urban runoff was observed with the greatest amount of precipitation during summer. Moderate rainfalls enhance the inflow of bioavailable dissolved mercury into water bodies. Despite the lack of industrial effluents entering the rivers directly, the sub-catchments with anthropogenic land use were important sources of Hg in the rivers. This was caused by elution of metal, deposited in soils over the past decades, into the rivers. The obtained results are especially important in the light of recent environmental conscience regulations, enforcing the decrease of pollution by Baltic countries. 相似文献
Environmental Science and Pollution Research - Through a variety of media formats, the Air Quality Health Index (AQHI) has served as a valuable communication tool for the general Canadian... 相似文献
Environmental Science and Pollution Research - The aims of the study were to investigate the concentration, sources and ecological risk of PAHs (polycyclic aromatic hydrocarbons) in bottom... 相似文献
Floods in the northern foreland of the Tatra Mountains considerably contribute to the total flood damage in Poland. Therefore, the question whether the magnitude and frequency of floods have changed in this region is of high interest. This study aims at investigating the inter-decadal variability of magnitude, frequency and seasonality of floods since the mid-twentieth century, to better understand regional changes. The analysis was accomplished in a multi-temporal approach whereby trends are fitted to every possible combination of start and end years in a record. Detected trends were explained by estimating correlations between the investigated flood parameters and different large-scale climate indices for the northern hemisphere, and by trends found in intense precipitation indices, number of days with snow cover, cyclonic circulation types, temperature and moisture conditions. Catchment and channel changes that occurred in the region over the past decades were also considered. Results show that rivers in the area exhibit considerable inter-decadal variability of flows. The magnitude and direction of short-term trends are heavily influenced by this inter-decadal variability; however, certain patterns are apparent. More extreme, although perhaps less frequent floods are now likely to occur, with a shift in the seasonality, decreasing flood magnitudes in winter and increasing during autumn and spring. The identification of the factors contributing to the occurrence of flood events and their potential changes is valuable to enhance the flood management in the region and to improve the resilience of the population in this mountainous area. 相似文献