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1.

The coronavirus disease 2019 (COVID-19) pandemic is still spreading all over the world. Although China quickly brought the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) under control in 2020, sporadic outbreaks have recurred from time to time. Outbreaks since June 2020 have suggested that the imported cold food supply chain is a major cause for the recurrence and spread of COVID-19. Here we review recurrent outbreaks in China from June 2020 to March 2021, and we analyse the main causes for recurrence and transmission by the supply of imported cold food from port to fork. Contaminated cold food or food packaging material can transmit the virus through ‘person-to-thing-to-person’, by contrast with the classical ‘person-to-person’ pathway. We decribe safety precautions for the food system, operating environment and people along the cold chain logistics. Surface disinfection and nucleic acid inspection are needed in each stage of the logistics of imported cold food supply.

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2.

Strengthening the immune system in order to better withstand the threat of COVID-19 is an important way to ensure the protection of our health against the current pandemic associated with SARS-CoV-2. There are many ways to achieve this, but with current circumstances, certain modalities stand out as being the most valid and are certainly worth greater consideration. Here we review the effects that particular immuno-strengthening activities can have on limiting the severity of COVID-19 disease as well as preventing virus infection. Physical activity, in particular, should not be discounted as an important method of prevention of viral diseases as it triggers many biological processes within the human body which in turn lead to heightened natural defences against viral infections. When exercise is performed in forested areas, these protective health benefits may be increased since many plant species emit biogenic volatile compounds (VOCs) which, when inhaled, have many protective properties. These VOCs have been shown in particular to have immunostimulatory effects on the human body and, thus, they could be of use in the prevention and/or treatment of COVID-19. Being amongst trees may also help to alleviate stress and anxiety, lowering cortisol levels and consequently helping the proper functioning of the immune system. In the following work, we have performed an analysis of the available scientific literature which looks at the effects of physical exercise as well as ‘forest-bathing’ on the immune system’s ability to fight disease, especially of course as it relates to COVID-19. Our review aims at shedding light on the benefits of exercising outdoors in green areas and suggests reforestation as a protective measure against future outbreaks.

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3.

Almost all aspects of society from food security to disease control and prevention have benefited from pharmaceutical and personal care products, yet these products are a major source of contamination that ends up in wastewater and ecosystems. This issue has been sharply accentuated during the coronavirus disease pandemic 2019 (COVID-19) due to the higher use of disinfectants and other products. Here we review pharmaceutical and personal care products with focus on their occurrence in the environment, detection, risk, and removal.

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4.
Li  Zhen  Yu  Shaocai  Li  Mengying  Chen  Xue  Zhang  Yibo  Li  Jiali  Jiang  Yapping  Liu  Weiping  Li  Pengfei  Lichtfouse  Eric 《Environmental Chemistry Letters》2022,20(1):59-69
Environmental Chemistry Letters - Despite large decreases of emissions of air pollution during the coronavirus disease 2019 (COVID-19) lockdown in 2020, an unexpected regional severe haze...  相似文献   

5.
Environmental Chemistry Letters - The outbreak of the human coronavirus disease 2019 (COVID-19) has induced an unprecedented increase in the use of several old and repurposed therapeutic...  相似文献   

6.
• Implication of COVID-19 on medical waste and MSW generation is studied. • Challenges and effective strategy of solid waste generation is reviewed. • 2.9 million tons of COVID-19 related medical waste has been generated until Sep. 22. • The pandemic has postponed policies related to the reduction of plastic use. • Blockade resulted in a significant drop in waste generation in some regions. It has been over ten months since the beginning of the 2019 coronavirus disease (COVID-2019), and its impact on solid waste management, especially medical waste, is becoming clearer. This study systematically reviews the potential influences of the COVID-19 pandemic on medical waste, personal protection equipment waste and municipal solid waste (MSW), and discusses the corresponding measures and policies of solid waste management in typical countries. The results show that the generation of medical waste from the pandemic increased significantly, with 18%‒425% growth. It is estimated that the daily output of COVID-19 medical waste increased from 200 t/d on Feb. 22 to over 29000 t/d at the end of September 2020 throughout the world. The use of personal protective equipment will continue to grow in the long-term, while the blockade and isolation measures greatly reduced the volume of commercial waste, especially for tourist cities, and part of this waste was transferred to household waste. Residents’ attitudes and behavior toward food waste have changed due to the COVID-19 pandemic. In response to the pandemic, international organizations and several countries have issued new policies and guidelines and adjusted their management strategies for medical waste and MSW treatment. The pandemic has brought specific challenges to the disposal capacity of medical waste worldwide. It has also brought about the stagnation of policies related to the reduction of plastic products and waste recycling. This study will provide some useful information for managers and governmental officials on effective solid waste management during and after the COVID-19 pandemic.  相似文献   

7.
Ji  Honglu  Tong  Huan  Wang  Jingge  Yan  Dan  Liao  Zangyi  Kong  Ying 《Environmental geochemistry and health》2022,44(9):3115-3132
Environmental Geochemistry and Health - With the expansion of the global novel coronavirus disease (COVID-19) pandemic, unprecedented interventions have been widely implemented in many countries,...  相似文献   

8.
外来入侵植物薇甘菊对华南地区的生态环境造成严重危害,为探讨薇甘菊叶片挥发性有机化合物在华南地区的空间差异,运用GC-MS分析了华南地区23个不同地理种群230个薇甘菊植株叶片挥发性有机化合物的组分,并用峰面积归一化法计算各组分相对含量;利用线性混合模型分析不同地理种群的气候环境因素对薇甘菊叶片挥发性有机化合物含量的影响;采用聚类分析和主成分分析23个不同地理种群薇甘菊叶片挥发性有机化合物组分的特征。结果表明:利用GC-MS从薇甘菊叶片中鉴定了42种挥发性有机化合物,其主要成分为β-荜澄茄油烯(24.63%)、β-石竹烯(16.81%)、大香叶烯D(10.47%)、α-古芸烯(9.95%)和α-姜烯(9.77%);线性混合模型分析结果显示经度、纬度、海拔高度和温度可显著影响薇甘菊叶片中5种主要挥发性有机化合物的含量;聚类分析和主成分分析表明薇甘菊叶片挥发性有机化合物组分表现出较强的地域特征。研究结果可为阐明薇甘菊的入侵机制及防控措施的制定提供理论与实践参考。  相似文献   

9.
《毒物与环境化学》2012,94(3-6):215-227
Abstract

Simulated with small environmental chambers, the emission characteristics of total volatile organic compounds from plastic runway surfaces were investigated by thermal desorption–gas chromatography–mass spectrometry. This quantitative approach was validated using a dynamic recovery experiment, and the variation of emission factors from mixed-type plastic surfaces was determined. Also, the photodegradation of volatile organic compounds in chambers was introduced to decrease the background interference.  相似文献   

10.
Environmental Chemistry Letters - Pollution and diseases such as the coronavirus pandemic (COVID-19) are major issues that may be solved partly by nanotechnology. Here we review the synthesis of...  相似文献   

11.
森林土壤的结构和贮水保水能力是决定土壤水分及其时空分布的关键,九寨沟和黄龙自然保护区均是以水为灵魂,其水量的多少及时空分布格局对景区景点的视觉观赏效果具有十分重要的作用.通过对几寨沟和黄龙核心景区原始林与次生林土壤容重、持水性能和孔隙度等指标的监测,探讨了不同植被类型下土壤结构及持水能力状况.结果表明:(1)由于较早地得到保护,九寨沟景区原始林、桦槭次生林土壤物理性质均优于四川西部其它同类犁植被,与此相反,人工云杉纯林土壤物理性质明显劣于其它植被类型,可能主要与云杉平根系统对土壤膨胀挤压和单优势乔木群落所形成的不利微气候影响有机物分解归还土壤有关;(2)在黄龙核心景区的原始云、冷杉林,发育于坡积母质的土壤物理性质明显优于发育于钙华母质卜的土壤物理性质.图3表1参31  相似文献   

12.
This study assesses the distribution of goiter in the Kalutara District, Sri Lanka in order to find causative factors for the occurrence of goiter even after the salt iodization. A questionnaire survey was conducted at the household level and at the same time iodine and selenium levels of the water sources were analyzed. Questionnaire survey results indicated the highest numbers of goiter patients in the northern part where the lowest were found in the southern sector which may be due to the presence of acid sulfate soils. Females were more susceptible and it even showed a transmittance between generations. Average iodine concentrations in subsurface water of goiter endemic regions are 28.25 ± 15.47 μg/L whereas non-goiter regions show identical values at 24.74 ± 18.29 μg/L. Surface water exhibited relatively high values at 30.87 ± 16.13 μg/L. Endemic goiter was reported in some isolated patches where iodine and selenium concentrations low, latter was <10 μg/L. The formation of acid sulfate soils in the marshy lands in Kalutara district may lead to transformation of biological available iodine oxidation into volatile iodine by humic substances, at the same time organic matter rich peaty soil may have strong held of iodine and selenium which again induced by low pH and high temperature were suggested as the instrumental factors in the endemic goiter in Kalutara district. Hence, geochemical features such as soil pH, organic matter and thick lateritic cap in the Kalutara goiter endemic area play a role in controlling the available selenium and iodine for food chain through plant uptake and in water.  相似文献   

13.
The concentrations and characteristics of volatile organic hazardous air pollutants (HAPs) in the urban city of Kaohsiung from motor vehicles and dense pollutant sources has become a national concern. To continuously monitor volatile organic HAPs, sampling sites were selected near the four air-quality monitoring stations established by Ethe nvironmental Protection Administration of Taiwan ROC, namely Nan-tz, Tso-ying, San-min and Hsiao-kang, from north to south. An on-site automated online monitor of volatile organic compounds (VOCs) was used for continuous monitoring. This study performed two consecutive days of 24-h monitoring of five volatile organic HAPs form August to October 2005 at the four monitoring sites, which cover the northern, central, and southern areas of Kaohsiung city. The average monitored concentration was 2.78–4.84 ppb for benzene, 5.90–9.66 ppb for toluene, 3.62–5.90 ppb for ethylbenzene, 3.73–5.34 ppb for m,p-xylene, 3.38–4.22 ppb for o-xylene, and 4.48–7.00 ppb for styrene. The average monitored concentrations of the major volatile organic HAPs tended to follow the pattern San-min > Nan-tz > Hsiao-kang > Tso-ying. Among all the species monitored in this study, toluene had the highest ambient concentration, followed by styrene, m,p-xylene, ethylbenzene, o-xylene, and benzene. The results showed that the concentration at night was higher than that in the day for toluene at Nan-tz, San-min, Hsiao-kang, and for benzene at Nan-tz and Hsiao-kang.  相似文献   

14.
In the Western Mediterranean Sea, the gorgonian Eunicella singularis (Esper, 1794) is found at high densities on sublittoral bottoms at depths from 10 to 70 m. Shallow colonies have symbiotic zooxanthellae that deeper colonies lack. While knowledge of the ecology of the shallow populations has increased during the last decades, there is almost no information on the ecology of the deep sublittoral populations. In October and November 2004 at Cap de Creus (42°19′12″ N; 03°19′34″ E), an analysis of video transects made by a remotely operated vehicle showed that shallow populations (10–25 m depth) were dominated by small, non-reproductive colonies, while deep sublittoral populations (50–67 m depth) were dominated by medium-sized colonies. Average and maximum colony heights were greater in the deeper populations, with these deeper populations also forming larger patch sizes and more extensive regions of continuous substrate coverage. These results suggest that shallow habitats are suitable for E. singularis, as shown by the high recruitment rate, but perturbations may limit or delay the development of these populations into a mature stage. This contrasts with the deep sublittoral habitats where higher environmental stability may allow the development of mature populations dominated by larger, sexually mature colonies.  相似文献   

15.
Many plant families have aromatic species that produce volatile compounds which they release when damaged, particularly after suffering herbivory. Monarda fistulosa (Lamiaceae) makes and stores volatile essential oils in peltate glandular trichomes on leaf and floral surfaces. This study examined the larvae of a specialist tortoise beetle, Physonota unipunctata, which feed on two M. fistulosa chemotypes and incorporate host compounds into fecal shields, structures related to defense. Comparisons of shield and host leaf chemistry showed differences between chemotypes and structures (leaves vs. shields). Thymol chemotype leaves and shields contained more of all compounds that differed than did carvacrol chemotypes, except for carvacrol. Shields had lower levels of most of the more volatile chemicals than leaves, but more than twice the amounts of the phenolic monoterpenes thymol and carvacrol and greater totals. Additional experiments measured the volatiles emitted from M. fistulosa in the absence and presence of P. unipunctata larvae and compared the flower and foliage chemistry of plants from these experiments. Flowers contained lower or equal amounts of most compounds and half the total amount, compared to leaves. Plants subjected to herbivory emitted higher levels of most volatiles and 12 times the total amount, versus controls with no larvae, including proportionally more of the low boiling point chemicals. Thus, chemical profiles of shields and volatile emissions are influenced by the amounts and volatilities of compounds present in the host plant. The implications of these results are explored for the chemical ecology of both the plant and the insect.  相似文献   

16.
Acacia longifolia, a highly invasive species that invades coastal ecosystems in Mediterranean areas, produces significant impacts at different scales. Abundant foliage and thick canopies create a dense atmosphere that led us to hypothesise that the release of volatile organic compounds (VOCs) could play a role in the reduction of biodiversity observed in invaded areas. Therefore, we suggested that VOCs emitted by A. longifolia could exert inhibitory effects on physiological and biochemical parameters of native species. Using glass chamber bioassays, we evaluated the effect of aerial contact between VOCs from different plant parts of A. longifolia material and some native species. Volatile chemical composition was further analysed using GC-MS. Our results indicated that VOCs produced a notably reduction of seed germination. Furthermore, volatiles from leaves and flowers significantly decreased root length, shoot length and biomass for all species. Proline and malondialdehyde content did not significantly increase after contact with VOCs. Finally, chemical profile of VOCs from flowers, leaves and litter was significantly different, both qualitatively and quantitatively. As far as we know, our results constitute the first evidence of phytotoxicity induced by VOCs from A. longifolia, suggesting that flowers and leaves could influence its surrounding environment through VOCs release.  相似文献   

17.
A study undertaken in the surface waters of the Gulf of Fos (France), revealed very low salinities, high nutrient concentrations, and very rich phytoplanktonic populations (maximum 7.5·105 cells/l). Very often the phytoplanktonic populations attain abundances 2 to 15 times higher than maximum population densities found in the Mediterranean Sea. Such high cellular concentrations seem to suppress more or less the rates of relative photosynthesis if the concentration of chlorophyll a per 1 million cells is considered. Furthermore, the analysis of particular carbon yields high values. This phenomenon can be explained by the fact that, in addition to organic carbon, other organic forms of carbon were measured, especially some carbonates which are abundant in fresh waters. The C/N ratios found seem to support this explanation.  相似文献   

18.
This study aims to determine aluminum fractions in the fine earth of acidic soils under different land uses (forest, pasture and cultivation) and in the river bed sediments of the headwater of the Mero River in order to identify and quantify Al-bearing phases to assess Al mobility and potential bioavailability (environmental availability) in the monitoring area. Sequential extraction is used to evaluate the Al partitioning into six fractions operationally defined: soluble/exchangeable/specifically adsorbed, bound to manganese oxides, associated with amorphous compounds, aluminum bound to oxidizable organic matter, associated with crystalline iron oxides, and residual fraction (aluminum within the crystal lattices of minerals). The mean concentration of total aluminum (24.01 g kg?1) was similar for the three considered uses. The mean percentage of the aluminum fractions, both in soils and sediments, showed the following order: residual fraction ? amorphous compounds ≈ crystalline iron oxides > water-soluble/exchangeable/specifically adsorbed > bound to oxidizable organic matter ≈ Mn oxides. However, in the soils, the amorphous compounds and water-soluble/exchangeable/specifically adsorbed fraction showed considerable differences between some types of uses, the percentage of aluminum linked to amorphous compounds being higher in forest soils (16% of total Al) compared to other uses (mean about 8% of total Al). The highest values of water-soluble/exchangeable/specifically adsorbed Al were also found in forest soils (mean 8.6% of the total Al versus about 4% of pasture and cultivation), which is consistent with the lower pH and higher organic matter content in forest soils. Nevertheless, the potentially bioavailable fraction (sum of the first three fractions) is low, suggesting very low geoavailability of this element in both soils and sediments; hence, the possibility to affect the crops and water quality is minimal.  相似文献   

19.
Seasonal changes in the concentration of nutrients and various organic compounds were studied in the waters surrounding mangroves and in the marshy areas of mangroves. Higher amounts of nutrients and organic compounds were observed during low tide. This is due to the remineralisation of plant detritus in this area. High concentration of carbohydrates, proteins, chlorophyll and phosphate were observed during monsoon, which can be attributed to the leaching of plant detritus as well as the land run-off. During pre-monsoon and post-monsoon high tannin and lignin concentration was noted. A 24-hour sampling was also done to study the tidal impact on the concentrations of various organic compounds and nutrients in this ecosystem. Even though a tidal impact was observed, a clear picture was not reported in this study.  相似文献   

20.
The most important constituents of traffic exhaust are carbon monoxide, nitrogen oxides, volatile organic compounds, polycyclic hydrocarbons and lead. Satisfactory analytical methods are available for measuring these compounds, but the required expenditure in their application to air pollution studies is quite different. Due to correlations between the concentrations of several exhaust components in road air conclusions regarding the expected level of some substances can be drawn by measurement of another emitted compound. But the selection of indicator compounds must be made under the aspect of the source‐specific relationship of emitted substances. The temporal and spatial distribution of air pollutants in street air is affected by traffic emissions more than by meteorological conditions. “Fingerprints”; of typical organic gaseous components of traffic exhaust also were found in residential areas.  相似文献   

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