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1.
In this preliminary study, we have investigated whether dermal uptake of nicotine directly from air or indirectly from clothing can be a meaningful exposure pathway. Two participants wearing only shorts and a third participant wearing clean cotton clothes were exposed to environmental tobacco smoke (ETS), generated by mechanically “smoking” cigarettes, for three hours in a chamber while breathing clean air from head‐enveloping hoods. The average nicotine concentration (420 μg/m3) was comparable to the highest levels reported for smoking sections of pubs. Urine samples were collected immediately before exposure and 60 hour post‐exposure for bare‐skinned participants. For the clothed participant, post‐exposure urine samples were collected for 24 hour. This participant then entered the chamber for another three‐hour exposure wearing a hood and clothes, including a shirt that had been exposed for five days to elevated nicotine levels. The urine samples were analyzed for nicotine and two metabolites—cotinine and 3OH‐cotinine. Peak urinary cotinine and 3OH‐cotinine concentrations for the bare‐skinned participants were comparable to levels measured among non‐smokers in hospitality environments before smoking bans. The amount of dermally absorbed nicotine for each bare‐skinned participant was conservatively estimated at 570 μg, but may have been larger. For the participant wearing clean clothes, uptake was ~20 μg, and while wearing a shirt previously exposed to nicotine, uptake was ~80 μg. This study demonstrates meaningful dermal uptake of nicotine directly from air or from nicotine‐exposed clothes. The findings are especially relevant for children in homes with smoking or vaping.  相似文献   

2.
Rainwater samples collected from different parts of Sri Lanka have been analyzed for their chemical constituents. It was observed that except for minor occurrences, “acid‐rain” is still not prevalent in Sri Lanka. Based on the chemical composition, the rainwater of Sri Lanka has been classified chemically into eight different types, the most dominant being Ca/Mg—HCO3, Ca—Cl and non‐dominant cation—HCO3 types. The wet zone of Sri Lanka, particularly the areas around the central highlands, form a special zone in that a number of chemically different rainwater types can be found in these regions. In contrast, the dry zone of Sri Lanka receives four distinct types of rainwater and conform to geographical zones.  相似文献   

3.
Trace element accumulation in the lichen Pseudevernia furfuracea (L.) Zopf was studied in the district of Acerra (province of Naples, southern Italy), one of the points forming Italy's Triangle of Death. P. furfuracea thalli, collected from Mt. Faito (province of Naples), were transplanted and exposed in bags at different sites in Acerra district, classified into three different site types (urban, rural and industrial). We aimed to test the hypothesis that P. furfuracea, when transplanted in the district of Acerra, would respond to air pollution accumulating trace elements and that element concentrations in the exposed lichens were different in relation to the three different environments, characterised by different pollution sources. Samples were exposed for six months, periodically collected and examined by ICP MS spectrometer assays to measure concentrations of 10 trace elements (Al, As, Cd, Cr, Cu, Fe, Mn, Pb, V and Zn). The exposed samples showed increases in concentrations of all the examined elements; the trace element concentrations were evaluated by calculating exposed to control (EC) ratios, for each site and each trace element, to better understand the accumulation rates. EC ratios were evaluated after 3 and 6 month exposures, at the end of spring and summer respectively: 6 month EC values were the highest. The urban sites showed EC ratios generally higher than industrial and rural; the most accumulated elements were Pb and Cu (at the urban sites), Cu and Zn (at the industrial sites), and Cu and As (at the rural sites). The chemical data were then processed using a multivariate approach (ordination, PCA) to better understand environmental gradients. Bioaccumulation data and PCA analysis showed the sampling sites separated by different trace element abundance. Trace element abundance patterns in the three site types are discussed in relation to the land use and the pollution sources.  相似文献   

4.
Samples were collected from rainwater, the resulting runoff in urban drainage channels and the Khoshk River (a seasonal river which passes through the city and receives urban drainage channels runoff). Major elements and selected heavy metals (Cu, Pb and Zn) concentrations were investigated for rainwater samples. Marine and non-marine sources of the elements in rainwater were investigated by calculation of Sea salt fraction, Non sea salt fraction and application of factor analysis. pH and mean concentrations of major ions and heavy metals (Cu, Pb and Zn) were compared to the results of similar studies in other countries. GIS interpolation maps indicated the impact of traffic pollution and Shiraz industrial complex on spatial distribution of Cu, Pb and Zn in rainwater. Major ions and Cu, Pb and Zn mean concentrations in runoff samples were also studied and compared to the rainwater results. Since the Khoshk River is the main runoff drainage channel in the city and is used for irrigation, its water quality was also examined.  相似文献   

5.
Samples from precipitation events collected at Erdemli during February 1996-June 1997 were analyzed to determine their particulate aluminium content, in addition to pH and conductivity measurements. Backward air mass trajectories corresponding to the rainy days were analyzed to determine potential source regions of acidic and alkaline constituents transported to the Cilician Basin. Approximately 28% of the rain samples were found to be acidic and the trajectories associated with half of the acid precipitation events were from the Mediterranean Basin and the Balkan Peninsula, while the other half were from the Anatolian mainland and local sources. Rain samples were found to be alkaline (58%), with their trajectories originating from North Africa and the Middle East. As a result of its CaCO3 content, mineral dust from these arid regions significantly increased the pH of rainwater.  相似文献   

6.
范晓虎 《安徽建筑》2006,13(4):153-153,156
雨水是新的污染源,早期雨水携带大量污染物直排水体。文章介绍了初期雨水的污染情况及各种排水体制的优缺点,阐述了雨水处理和选择合理的排水体制的重要意义。  相似文献   

7.
Characterization of spatial variation of urban soil geochemistry especially heavy metal pollution is essential for a better understanding of pollution sources and potential risks. A total of 294 surface soil samples were collected from a roadside sports ground in Galway, Ireland, and were analysed by ICP-OES for 23 chemical elements (Al, Ca, Ce, Co, Cu, Fe, K, La, Li, Mg, Mn, Na, Ni, P, Pb, S, Sc, Sr, Th, Ti, V, Y and Zn). Strong variations in soil geochemistry were observed and most elements, with the exception of Cu, Pb, P, S and Zn, showed multi-modal features, indicating the existence of mixed populations which proved difficult to separate. To evaluate the pollution level of the study area, the pollution index (PI) values were calculated based on a comparison with the Dutch target and intervention values. None of the concentrations of metal pollutants exceeded their intervention values, indicating the absence of serious contaminated soil, and the ratios to target values were therefore employed to produce the hazard maps. The spatial distribution and hazard maps for Cu, Pb and Zn indicated relatively high levels of pollution along the southern roadside extending almost 30 m into the sports ground, revealing the strong influence of pollution from local traffic. However, heavy metal pollution was alleviated along the eastern roadside of the study area by the presence of a belt of shrubs. Therefore, in order to prevent further contamination from traffic emissions, the planting of hedging or erection of low walls should be considered as shields against traffic pollution for roadside parks. The results in this study are useful for management practices in sports and parks in urban areas.  相似文献   

8.
This study aims to elucidate in greater detail the dermal uptake of nicotine from air or from nicotine‐exposed clothes, which was demonstrated recently in a preliminary study. Six non‐smoking participants were exposed to gaseous nicotine (between 236 and 304 μg/m3) over 5 hours while breathing clean air through a hood. Four of the participants wore only shorts and 2 wore a set of clean clothes. One week later, 2 of the bare‐skinned participants were again exposed in the chamber, but they showered immediately after exposure instead of the following morning. The 2 participants who wore clean clothes on week 1 were now exposed wearing a set of clothes that had been exposed to nicotine. All urine was collected for 84 hours after exposure and analyzed for nicotine and its metabolites, cotinine and 3OH‐cotinine. All participants except those wearing fresh clothes excreted substantial amounts of biomarkers, comparable to levels expected from inhalation intake. Uptake for 1 participant wearing exposed clothes exceeded estimated intake via inhalation by >50%. Biomarker excretion continued during the entire urine collection period, indicating that nicotine accumulates in the skin and is released over several days. Absorbed nicotine was significantly lower after showering in 1 subject but not the other. Differences in the normalized uptakes and in the excretion patterns were observed among the participants. The observed cotinine half‐lives suggest that non‐smokers exposed to airborne nicotine may receive a substantial fraction through the dermal pathway. Washing skin and clothes exposed to nicotine may meaningfully decrease exposure.  相似文献   

9.
The aim of this study was to determine the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), manganese (Mn), lead (Pb), and vanadium (V) in soil and chard samples collected in various industrial sites of Tarragona County (Spain), an area with an important number of petrochemical industries. Samples were also collected in urban (Tarragona downtown) and presumably unpolluted (blank samples) sites. Human health risks derived from metal inhalation and ingestion of soils were also assessed. With the exception of an increase in the levels of Cd and V, significant differences in soil samples from the industrial and the unpolluted zone were not found. In chard samples, significant differences between collection sites were only noted for V concentrations. For non-carcinogenic risks, the current levels of metals in the industrial area were lower than those considered as safe for the general population. In relation to carcinogenic risks, only As ingestion and Cr inhalation in the industrial zone might potentially cause an increase of the cases of cancer. A Kohonen self-organized map (an Artificial Neural Network) showed differences in metal concentrations according to the zone of origin of the samples. The current results suggest that although in general terms the petrochemical complex is not a relevant metal pollution source for the area, attention should be paid to As, Cr and V.  相似文献   

10.
We estimated the impact of a smoke‐free workplace bylaw on non‐smoking bar workers' health in Ontario, Canada. We measured bar workers' urine cotinine before (= 99) and after (= 91) a 2004 smoke‐free workplace bylaw. Using pharmacokinetic and epidemiological models, we estimated workers' fine‐particle (PM2.5) air pollution exposure and mortality risks from workplace secondhand smoke (SHS). workers' pre‐law geometric mean cotinine was 10.3 ng/ml; post‐law dose declined 70% to 3.10 ng/ml and reported work hours of exposure by 90%. Pre‐law, 97% of workers' doses exceeded the 90th percentile for Canadians of working age. Pre‐law‐estimated 8‐h average workplace PM2.5 exposure from SHS was 419 μg/m3 or ‘Very Poor’ air quality, while outdoor PM2.5 levels averaged 7 μg/m3, ‘Very Good’ air quality by Canadian Air Quality Standards. We estimated that the bar workers' annual mortality rate from workplace SHS exposure was 102 deaths per 100 000 persons. This was 2.4 times the occupational disease fatality rate for all Ontario workers. We estimated that half to two‐thirds of the 10 620 Ontario bar workers were non‐smokers. Accordingly, Ontario's smoke‐free law saved an estimated 5–7 non‐smoking bar workers' lives annually, valued at CA $50 million to $68 million (US $49 million to $66 million).  相似文献   

11.
X. Duan  B. Wang  X. Zhao  G. Shen  Z. Xia  N. Huang  Q. Jiang  B. Lu  D. Xu  J. Fang  S. Tao 《Indoor air》2014,24(5):464-473
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/m3, respectively, while, for the rural residents, they were 770 (504–1071) and 312 (201–412) ng/m3, 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.  相似文献   

12.
Alkyllead compounds have been analysed in road drainage water samples collected during seven storm events using a sensitive gas chromatography-atomic absorption technique. The most commonly observed alkyllead species were tetraethyllead, triethyllead and trimethyllead. Similar compounds were also observed in rainwater collected at the site, but not in road surface dust or bottom sediment from the drainage channel. In all samples analysed the concentration of alkyllead was < 5% of the dissolved (< 0.45 μm) inorganic lead. It is postulated that washout of alkyllead from the atmosphere is the major source of alkyllead compounds in the drainage waters analysed. Alkyllead species were also identified in rainwater collected at other sites.  相似文献   

13.
我国城市道路雨水径流污染状况及控制措施   总被引:10,自引:1,他引:9  
道路是城市汇水面的重要组成部分,也是城市受纳水体非点源污染的主要污染源之一,道路雨水径流污染问题日益引起人们的重视.总结了道路雨水径流污染物成分、来源,对国内外道路雨水径流的EMC进行了对比分析,基于对我国城市道路排水现状的调研分析和部分雨水径流水质数据,对我国几个主要城市道路雨水径流年污染负荷进行了估算,并归纳推荐了一些针对我国道路排水现状的适用性控制措施,同时对我国城市雨水径流污染控制提出了几点建议.  相似文献   

14.
This paper presents results of analysis of animal feed and meat (cattle, horse and sheep) products from a metal processing region (Oskemen) in east Kazakhstan. Samples were collected from a range of districts of differing distances from the main source of anthropogenic pollution and with differing underlying metal-containing geologies. Analyses for cadmium, lead and zinc revealed high concentrations in many feed and meat samples. Horse (an important food animal) samples had higher levels of contamination than cattle, which were higher than sheep. For example, mean cadmium concentrations in horse kidneys in one district were found to be 128 mg/kg and lead concentrations for liver 2.2 mg/kg. These, and other, results are generally higher than reported in many other studies in contaminated regions of eastern Europe and they can exceed State Maximal Allowed Concentrations by many times. As such levels of contamination pose a significant potential risk to human health, these results have formed the basis for subsequent research on levels of metal contamination in human tissues from affected populations.  相似文献   

15.
空调冷凝水与雨水收集联合系统的可行性分析   总被引:1,自引:1,他引:0  
提出了一种空调冷凝水和雨水收集联合系统,该系统能够收集夏季雨天的雨水,晴天的冷凝水,在一定程度上克服了现有雨水收集系统运行的不连续性。同时,利用溶液热交换器收集了冷凝水的部分冷量,用以降低冷凝负荷,从而降低了空调的功耗。将全部的空调冷凝水回收利用,消除了空调冷凝水对建筑物的腐蚀等危害。能够有效达到节能减排的目的。  相似文献   

16.
Entry of contaminants, such as metals and non-metals, into rainwater harvesting systems can occur directly from rainfall with contributions from collection surfaces, accumulated debris and leachate from storage systems, pipes and taps. Ten rainwater harvesting systems on the east coast of Australia were selected for sampling of roof runoff, storage systems and tap outlets to investigate the variations in rainwater composition as it moved throughout the system, and to identify potential points of contribution to elemental loads. A total of 26 elements were screened at each site. Iron was the only element which was present in significantly higher concentrations in roof runoff samples compared with tank tap samples (P < 0.05). At one case study site, results suggested that piping and tap material can contribute to contaminant loads of harvested rainwater. Increased loads of copper were observed in hot tap samples supplied by the rainwater harvesting system via copper piping and a storage hot water system (P < 0.05). Similarly, zinc, lead, arsenic, strontium and molybdenum were significantly elevated in samples collected from a polyvinyl chloride pipe sampling point that does not supply household uses, compared with corresponding roof runoff samples (P < 0.05). Elemental composition was also found to vary significantly between the tank tap and an internal cold tap at one of the sites investigated, with several elements fluctuating significantly between the two outlets of interest at this site, including potassium, zinc, manganese, barium, copper, vanadium, chromium and arsenic.These results highlighted the variability in the elemental composition of collected rainwater between different study sites and between different sampling points. Atmospheric deposition was not a major contributor to the rainwater contaminant load at the sites tested. Piping materials, however, were shown to contribute significantly to the total elemental load at some locations.  相似文献   

17.
The determination of the total concentration of selenium does not provide sufficient information about its toxicity and its bioavailability. The determination of its chemical forms is the basis for understanding the biogeochemical cycle in terrestrial and aquatic ecosystems and for detecting the species which might be toxic to biota. In this work we describe an analytical procedure to carry out the redox speciation of selenium present at ultratrace levels in rainwater from sites of Valparaiso region in Chile, impacted by mining activities of copper ores. A simple preconcentration step of the rainwater sample on a rotavapor system, in vacuum at low temperature permits the concentration of the different redox selenium species until levels quantifiable by sensitive techniques such as differential pulse cathodic stripping voltammetry or by spectrometric techniques, based on the hydride generation and detection by atomic absorption or atomic fluorescence spectrometry. These techniques coupled to redox chemical reactions allow the redox speciation of selenium. The results show that the open evaporation system can be used to concentrate water samples when the aim of the analysis is the determination of the total selenium concentration. On the contrary, to carry out its redox speciation only the preconcentration performed on rotavapor system, in vacuum can be used. When synthetic solutions containing different redox species of selenium, at ultratrace levels, were slowly evaporated on open system, Se(II) and Se(IV) were oxidized. The optimized procedure was then applied to the selenium determination and its redox speciation in rainwater samples collected in sites impacted by mining activities of copper ores. It was found that the amounts of total selenium in rainwater, as copper, from Puchuncavi valley decrease exponentially with the distance from the source, indicating that these elements in this region arise from the industrial complex Las Ventanas. In the redox speciation of selenium, Se(IV) and Se(VI) were the species found in all rainwater samples analyzed, providing selenium in species which are most favorable for their uptake by the vegetation grown in these soils.  相似文献   

18.
Properly apportioning the loads of metals in highway stormwater runoff to the appropriate sources requires accurate data on source composition, especially regarding constituents that help to distinguish among sources. Representative tire and brake samples were collected from privately owned vehicles and aqueous extracts were analyzed for twenty-eight elements. Correlation principal components analysis (PCA) revealed that tires were most influenced by Zn, Pb, and Cu, while brakes were best characterized by Na and Fe followed by Ba, Cu, Mg, Mn, and K; the latter three may be due to roadside soil contributions. Notably elevated Cd contributions were found in several brake samples. A targeted Cd-plated brake rotor was sampled, producing results consistent with the elevated levels found in the larger sample population. This enriched source of Cd is of particular concern due to high toxicity of Cd in aquatic ecosystems.  相似文献   

19.
《Urban Water Journal》2013,10(6):441-448
The levels of organonitrogen, organochlorine and organophosphorus pesticides were monitored in rain and roof runoff waters in Gdańsk (Poland) over a period of 6 months (October 2000 – March 2001). Buildings included in the study were of different ages, and covered with a variety of roofing materials. Samples were collected during the precipitation events. Pesticides were determined by gas chromatography combined with NPD and ECD detection. Bromofos, heptachlor epoxide and o,p′-DDE were detected the most often in the samples collected. In general, pesticide concentrations were higher in roof runoff than in rainwater. The type of the roofing material had a significant effect on the pesticide levels in runoff waters. The highest analyte levels were recorded in October and November, when the temperature was the highest.  相似文献   

20.
Cooking is recognized as an important source of particulate pollution in indoor and outdoor environments. We conducted more than 100 individual experiments to characterize the particulate and non‐methane organic gas emissions from various cooking processes, their reaction rates, and their secondary organic aerosol yields. We used this emission data to develop a box model, for simulating the cooking emission concentrations in a typical European home and the indoor gas‐phase reactions leading to secondary organic aerosol production. Our results suggest that about half of the indoor primary organic aerosol emission rates can be explained by cooking. Emission rates of larger and unsaturated aldehydes likely are dominated by cooking while the emission rates of terpenes are negligible. We found that cooking dominates the particulate and gas‐phase air pollution in non‐smoking European households exceeding 1000 μg m?3. While frying processes are the main driver of aldehyde emissions, terpenes are mostly emitted due to the use of condiments. The secondary aerosol production is negligible with around 2 μg m?3. Our results further show that ambient cooking organic aerosol concentrations can only be explained by super‐polluters like restaurants. The model offers a comprehensive framework for identifying the main parameters controlling indoor gas‐ and particle‐phase concentrations.  相似文献   

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