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911.
Objective: The influence of different exposures to PM2.5 (particulate matter with an aerodynamic diameter below 2.5?μm) on the concentrations of biomarkers of exposure and oxidative stress should be investigated. For this purpose, urine samples from individuals travelling from Germany to China were collected and analysed.

Materials: Robust LC and LC-MS/MS methods were established for the determination of biomarkers including 8-hydroxy-2′-deoxyguanosine, malondialdehyde, F-isoprostanes and hydroxylated polycyclic aromatic hydrocarbons. As a pilot study, nine volunteers travelled from Germany (mean daily concentration of PM2.5: 21?μg/m3) to China (mean daily concentration of PM2.5: 108?μg/m3). Urine samples were collected before and after the trip.

Results: In samples collected after return to Germany, the median concentrations of oxidative stress biomarkers were observed to be higher than in samples collected before leaving Germany. Decreasing trends were observed in the sequences of samples collected after return in the following weeks. Correlations were found between exposure and oxidative stress biomarkers.

Conclusion: Travellers are ideal models for PM pollution-induced acute health effects study. Exposure to PM pollution can cause oxidative stress and damage.  相似文献   

912.
913.
赵晓菊  秦薇  陈华峰 《植物研究》2017,37(1):155-160
高含量不饱和脂肪酸,特别是高含量亚麻酸是牡丹籽油品质的主要体现,但到目前为止,在凤丹传统栽培区(铜矿区)土壤铜含量是否影响牡丹籽油品质并没有被调查。本研究通过调查安徽省凤凰山-丫山30个凤丹(Paeonia ostii)栽培区土壤Cu元素含量和凤丹籽油组成,显示凤丹栽培区土壤铜含量为18.98~298.82 mg·kg-1,变异系数为83.06%;凤丹籽油中棕榈酸、硬脂酸、油酸、亚油酸和亚麻酸5种主要脂肪酸含量分别为5.62%、1.89%、24.59%、29.76%、38.13%,变异系数在5.66~9.72,其中亚油酸变异系数最高为9.72;土壤和叶片中Cu含量与亚油酸和不饱和脂肪酸含量均存在明显的负相关性,与亚麻酸含量没有显著相关性;土壤和叶片中Cu含量呈显著正相关,r=0.778。以上表明以油用为目的的凤丹栽培应该避免土壤中铜含量过高影响牡丹籽油品质。  相似文献   
914.
Environmental contamination is a common cause of rapid evolution. Recent work has shown that Daphnia pulex, an important freshwater species, can rapidly evolve increased tolerance to a common contaminant, sodium chloride (NaCl) road salt. While such rapid evolution can benefit organisms, allowing them to adapt to new environmental conditions, it can also be associated with unforeseen tradeoffs. Given that exposure to environmental contaminants can cause circadian disruption, we investigated whether the circadian clock was affected by evolving a tolerance to high levels of road salt. By tracking the oscillations of a putative clock gene, period, we demonstrated that D. pulex express per mRNA with approximately 20‐hr oscillations under control conditions. This putative circadian rhythm was ablated in response to high levels of salinity; populations adapted to high NaCl concentrations exhibited an ablation of period oscillation. Moreover, we showed that while gene expression is increased in several other genes, including clock, actin, and Na+/K+‐ATPase, upon the adaptation to high levels of salinity, per expression is unique among the genes we tracked in that it is the only gene repressed in response to salt adaptation. These results suggest that rapid evolution of salt tolerance occurs with the tradeoff of suppressed circadian function. The resultant circadian disruption may have profound consequences to individuals, populations, and aquatic food webs by affecting species interactions. In addition, our research suggests that circadian clocks may also be disrupted by the adaptation to other environmental contaminants.  相似文献   
915.
Traffic-related air pollution (TRAP), including particulate matter (PM) in respirable coarse and fine size fractions (PM10 and PM2.5), is known to have exposure effects on human health and environment. Real-time PM10 and PM2.5 concentrations were collected from the study locations in Bangkok, Thailand, using TSI AM510 particle counters. Temperature and % relative humidity (%RH) were also collected. Data were compared to data from the closest station of the Pollution Control Department (PCD), Thailand. Real-time mean concentration varied from 86 to 1107 µg/m3 (PM10) and varied from 25 to 664 µg/m3 (PM2.5). In addition, real-time mean PM10 (223.1 µg/m3) was nearly four times greater than that measured by the PCD station, 60 µg/m3. Temperature and %RH from real-time air monitoring and PCD station were comparable. In each study location (five locations, two in morning and afternoon/evening), there were significant positive correlations between PM10 and PM2.5 concentrations and significant negative correlations between temperature and RH%. Results suggested that outdoor TRAP via measured real-time PM concentrations were more realistic exposure concentration estimates among street vendors as related to respiratory and other symptoms than data obtained from PCD station. Nevertheless, PM10 as measured by the PCD station might be a reasonable surrogate for estimated outdoor PM2.5 exposure.  相似文献   
916.
Heavy metals contamination from anthropogenic sources in waterways of conserved mangrove ecosystem (Indian Sundarbans) poses serious health hazard to the economically marginalized ‘tiger prawn seed’ (TPS) collectors. Principal component analysis identifies Pb, Ni and Cd as anthropogenic pollutant in Indian Sundarbans. It is observed that Cu, Fe and Zn concentration increases in monsoon, whereas concentration of Cd and Pb decreases in comparison to pre-monsoon levels at all seven fishing villages. Economic status has been assessed using Wealth Rank Tool, which indicates 16–71% of population is in acute economic stress conditions and 5–70% of populations engaged in unsustainable TPS collection for their livelihood. Focus group discussion shows that collectors are exposed (exposure time (ET)) to contaminated water for 3–7 h/d, and lifetime exposure (exposure duration (ED)) varies from 5 to 20 yr. Using site-specific ET and ED results, cumulative hazard quotient (HQ) dermal is estimated to be higher in female than in male. HQ varies from medium (≥1 to <4) to high (>4) due to Cd pollution (0.1–0.26 mg L-1). The study suggests that promoting alternative sustainable livelihood through group-based organizations (poultry, organic farming, entrepreneurship and transport) could be an effective solution to this problem.  相似文献   
917.
Cooking is a significant source of indoor air pollution (IAP) and is associated with significant morbidity and mortality. Liquefied petroleum gas (LPG; predominant cooking fuel of urban India), though safer than solid fuels, emits significant concentration of fine particles, NOx and several other pollutants, which may trigger respiratory ailments. Effect of exposure to pollutants, generated from fuel combustion and cooking activities, on subjects of different microenvironments has been assessed by carrying out a health survey using a questionnaire and by conducting spirometry. A significant increase in prevalence of cough and impairment of lung functions has been found among cooks compared to non-cooks. A significant difference in prevalence of cough between smoker and non-smoker non-cooks but no such difference in cooks suggests that kitchen pollutants and smoking have similar effects on respiratory system. Comparison of lung functions (average FEV1% predicted and average FVC% predicted) of cooks (90.6% and 82.6%) and non-cooks (93.7% and 86.2%) shows a significant difference in certain categories. The study brings out a close association between different kitchen microenvironments and specific respiratory parameters, signifying short- and long-term impairment. The impairment is prevalent in both rural and urban Indian cooks, signifying that fuel usage (biomass and LPG) and cooking practices play a prominent role in affecting respiratory health.  相似文献   
918.
919.
This study was the first to investigate the direct effects of anomalous concentrations of ozone mediated by summer heat waves on seed germination in alpine plants. During germination, the seeds were exposed to three peaks of O3 concentration (125 ppb for 5 and 10 days; 185 ppb for 5 days), derived from measurements taken close to the species growing site. High O3 concentration delayed the first germination time, increased the mean germination time, and reduced the germination percentage during and immediately after the treatment, but, in most cases, effects were weak and had almost vanished three weeks after the treatments. In few cases, chronic exposure to O3 (125 for 10 days’ treatment) enhanced seed germination compared to the control, suggesting that ozone may induce antioxidant and DNA-repair mechanisms or dormancy-breaking effects in hydrated seeds. Although seed mortality increased during O3 treatments in four species, the effect of O3 on seed germination is mostly limited to the period of exposure, indicating that it is unlikely to produce permanent negative effects on seeds, during the germination phase. Our results show that the direct effect of O3 on seeds of alpine plants may have minor impacts on plant reproductive performance during seed germination.  相似文献   
920.
The intensification of agricultural land use and urbanisation has increased nutrient loads in aquatic ecosystems. Nitrogen loads can alter ecosystem structure and functioning, resulting in increased algal productivity, algal blooms and eutrophication. The principal aim of the present paper is to extend the use of epilithic δ15N signatures to a lake ecosystem in order to evaluate the potential impact of anthropogenic nitrogen discharges (organic and inorganic) that can also reach coastal waters.Epilithic associations were collected from volcanic rocks in different seasons in shallow water along the entire perimeter of Lake Bracciano and analysed for their nitrogen stable isotope signatures. Furthermore, some stones were moved from an unpolluted site to a polluted one in order to verify the effect on the nitrogen signature of the epilithic association. The epilithon’s δ15N signatures provided strong evidence of the space-time variability of N inputs. The differing quality of nitrogen loads was reflected in high isotopic variation within the lake, especially at the beginning of summer (1.7‰  δ15N  13.3‰), while in winter, when anthropogenic pressure was lowest, the δ15N signature variation was less accentuated (3.1‰  δ15N  7.6‰). At all sampling times, spatial variability was found to be related to the various human activities along the lake shore (especially tourism and agriculture), while seasonal variation at all sampling sites was related to the intensity of anthropogenic pressures (higher in summer and lower in winter).Our results showed that epilithic algal associations and the physicochemical properties of the water did not influence the δ15N signature, which in contrast was strongly related to the site-specific effect of human activities around the lake. Thus, the distribution of δ15N across space and time can be used to direct nutrient reduction strategies in the region and can assist in monitoring the effectiveness of environmental protection measures.  相似文献   
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