scholarly journals Microplastic Contamination of Surface Water-Sourced Tap Water in Hong Kong—A Preliminary Study

2020 ◽  
Vol 10 (10) ◽  
pp. 3463 ◽  
Author(s):  
Theresa Wing Ling Lam ◽  
Hiu Tung Ho ◽  
Anson T.H. Ma ◽  
Lincoln Fok
Keyword(s):  
Hong Kong ◽  
Surface Water ◽  
Tap Water ◽  
Polluted Water ◽  
Atmospheric Input ◽  
Mechanical Abrasion ◽  
Wide Range ◽  
Potential Sources ◽  
Preliminary Study ◽  
Mean Concentration

Microplastics have been documented in a wide range of commercially available food products, and the presence of microplastics in tap water has received considerable attention in recent years. Although microplastics in drinking water pose a low concern for human health at current levels of exposure, there is a need to understand the potential pathways for human microplastic exposure. With the application of Rose Bengal staining, microplastics in 110 surface water-sourced tap water samples from urban sources in Hong Kong were qualified and morphologically characterized. A total of 224 items were identified in 86 (78.2%) samples with a mean concentration of 2.181 ± 0.165 n L−1. Fibrous and smaller (<1 mm) microplastics predominated in samples, accounting for 97.8% and 65.1% of the total microplastic count, respectively. Our results indicated a comparatively low level of microplastic contamination of tap water in Hong Kong. The potential sources of microplastics could be microplastic-polluted water bodies, atmospheric input and mechanical abrasion of plastic equipment during water treatment and distribution.

scholarly journals Recent developments in materials used for the removal of metal ions from acid mine drainage

2021 ◽  
Vol 11 (2) ◽  
Author(s):  
Tebogo M. Mokgehle ◽  
Nikita T. Tavengwa
Keyword(s):  
Heavy Metal ◽  
Surface Water ◽  
Acid Mine Drainage ◽  
Metal Ions ◽  
Mine Drainage ◽  
Acid Mine ◽  
Adsorption Capacities ◽  
Ion Imprinted ◽  
Wide Range ◽  
Ion Imprinted Polymers

AbstractAcid mine drainage is the reaction of surface water with sub-surface water located on sulfur bearing rocks, resulting in sulfuric acid. These highly acidic conditions result in leaching of non-biodegradeable heavy metals from rock which then accumulate in flora, posing a significant environmental hazard. Hence, reliable, cost effective remediation techniques are continuously sought after by researchers. A range of materials were examined as adsorbents in the extraction of heavy metal ions from acid mine drainage (AMD). However, these materials generally have moderate to poor adsorption capacities. To address this problem, researchers have recently turned to nano-sized materials to enhance the surface area of the adsorbent when in contact with the heavy metal solution. Lately, there have been developments in studying the surface chemistry of nano-engineered materials during adsorption, which involved alterations in the physical and chemical make-up of nanomaterials. The resultant surface engineered nanomaterials have been proven to show rapid adsorption rates and remarkable adsorption capacities for removal of a wide range of heavy metal contaminants in AMD compared to the unmodified nanomaterials. A brief overview of zeolites as adsorbents and the developent of nanosorbents to modernly applied magnetic sorbents and ion imprinted polymers will be discussed. This work provides researchers with thorough insight into the adsorption mechanism and performance of nanosorbents, and finds common ground between the past, present and future of these versatile materials.

scholarly journals Diffuse Water Pollution from Agriculture: A Review of Nature-Based Solutions for Nitrogen Removal and Recovery

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1893
Author(s):  
Giuseppe Mancuso ◽  
Grazia Federica Bencresciuto ◽  
Stevo Lavrnić ◽  
Attilio Toscano
Keyword(s):  
Water Pollution ◽  
Nitrogen Removal ◽  
Plant Uptake ◽  
Environmental Issues ◽  
Polluted Water ◽  
Health Issues ◽  
Agricultural Wastewater ◽  
Research Activities ◽  
Wide Range ◽  
Different Types

The implementation of nature-based solutions (NBSs) can be a suitable and sustainable approach to coping with environmental issues related to diffuse water pollution from agriculture. NBSs exploit natural mitigation processes that can promote the removal of different contaminants from agricultural wastewater, and they can also enable the recovery of otherwise lost resources (i.e., nutrients). Among these, nitrogen impacts different ecosystems, resulting in serious environmental and human health issues. Recent research activities have investigated the capability of NBS to remove nitrogen from polluted water. However, the regulating mechanisms for nitrogen removal can be complex, since a wide range of decontamination pathways, such as plant uptake, microbial degradation, substrate adsorption and filtration, precipitation, sedimentation, and volatilization, can be involved. Investigating these processes is beneficial for the enhancement of the performance of NBSs. The present study provides a comprehensive review of factors that can influence nitrogen removal in different types of NBSs, and the possible strategies for nitrogen recovery that have been reported in the literature.

scholarly journals The Use of Non-Nutritive and Low-Calorie Sweeteners in 19,915 Local and Imported Pre-Packaged Foods in Hong Kong

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1861
Author(s):  
Billy Yin Sing O ◽  
Daisy H. Coyle ◽  
Elizabeth K. Dunford ◽  
Jason H.Y. Wu ◽  
Jimmy Chun Yu Louie
Keyword(s):  
Hong Kong ◽  
Health Concern ◽  
Free Sugar ◽  
Cross Sectional ◽  
Low Calorie ◽  
Snack Foods ◽  
Wide Range ◽  
Different Types ◽  
Packaged Foods ◽  
Prepackaged Foods

This study aims to examine the use of non-nutritive (NNSs) and low-calorie sweeteners (LCSs) in pre-packaged foods in Hong Kong and the differences in the number of NNSs/LCSs used between products from different regions. In a cross-sectional audit, the types of NNSs/LCSs used in 19,915 pre-packaged foods in Hong Kong were examined by searching the ingredients list of the included products for keywords related to 20 common NNSs/LCSs and their respective E-numbers. Prevalence of use of NNSs and LCSs, the co-presence of NNSs/LCSs and free sugar ingredients (FSI), and the number of NNSs/LCSs used in the included foods were computed. Pearson’s χ2 test was used to compare the total number of NNSs and/or LCSs used in food items from different regions. Sucralose (E955) was the most commonly used NNS (1.9%), followed by acesulfame K (E950, 1.6%). Sorbitol was the most commonly used LCS (2.9%). Overall, the use of LCSs was less common compared with NNSs (3.7% vs. 4.5%). The use of different types of NNSs varied substantially between food types. Notably, 20.2% of potato crisps and 15.2% of other crisps or extruded snacks contained at least one NNS and/or LCS. Co-presence of FSIs and NNSs/LCSs were most common in confectionery (15.7%) and snack foods (15.5%). Asian prepackaged foods were more likely to contain NNSs/LCSs (10.1%) compared with those from other regions. To conclude, NNSs/LCSs were used in a wide range of non-diet pre-packaged products which could be a public health concern due to their higher consumption frequencies than “diet” products.

scholarly journals An Insight into Saponins from Quinoa (Chenopodium quinoa Willd): A Review

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1059 ◽  
Author(s):  
Khadija El Hazzam ◽  
Jawhar Hafsa ◽  
Mansour Sobeh ◽  
Manal Mhada ◽  
Moha Taourirte ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Bitter Taste ◽  
Biological Activities ◽  
Chenopodium Quinoa ◽  
Toxic Effects ◽  
Mechanical Abrasion ◽  
Important Group ◽  
The Past ◽  
Wide Range ◽  
Insight Into

Saponins are an important group found in Chenopodium quinoa. They represent an obstacle for the use of quinoa as food for humans and animal feeds because of their bitter taste and toxic effects, which necessitates their elimination. Several saponins elimination methods have been examined to leach the saponins from the quinoa seeds; the wet technique remains the most used at both laboratory and industrial levels. Dry methods (heat treatment, extrusion, roasting, or mechanical abrasion) and genetic methods have also been evaluated. The extraction of quinoa saponins can be carried out by several methods; conventional technologies such as maceration and Soxhlet are the most utilized methods. However, recent research has focused on technologies to improve the efficiency of extraction. At least 40 saponin structures from quinoa have been isolated in the past 30 years, the derived molecular entities essentially being phytolaccagenic, oleanolic and serjanic acids, hederagenin, 3β,23,30 trihydroxy olean-12-en-28-oic acid, 3β-hydroxy-27-oxo-olean-12en-28-oic acid, and 3β,23,30 trihydroxy olean-12-en-28-oic acid. These metabolites exhibit a wide range of biological activities, such as molluscicidal, antifungal, anti-inflammatory, hemolytic, and cytotoxic properties.

A Preliminary Study on Saving Parking Lot

2011 ◽  
Vol 368-373 ◽  
pp. 3628-3631
Author(s):  
Jun Liu ◽  
Wei Xian Zhang
Keyword(s):  
Sustainable Development ◽  
Large Area ◽  
The Sustainable Development ◽  
Parking Lots ◽  
Wide Range ◽  
Parking Lot ◽  
Preliminary Study

Along with the development of society and the popularity of private cars, more and more parking lots are to be needed. Consequently, large sized parking lots will be built in many cities. But the traditional parking lots were paved by a large area of concrete. So much concrete will be bound to create heat pollution. Meanwhile, a large area of parking lot occupies mass openspace. The existing parking lots lead to a waste of resources. This paper introduces a new term of saving parking lot and presents some key principles that stem from a wide range of contributions. The newfashioned parking lot may also give rise to the sustainable development.

Preliminary study of Hong Kong rainfall

1996 ◽  
Vol 30 (13) ◽  
pp. 2453-2454 ◽  
Author(s):  
P.A. Tanner ◽  
S.C. Cheung ◽  
K.Y. Cheung ◽  
L.M. Ho ◽  
F.P. Kan ◽  
...  
Keyword(s):  
Hong Kong ◽  
Preliminary Study

Memories of Tiananmen

2021 ◽  
Author(s):  
Francis Lee ◽  
Joseph Man Chan
Keyword(s):  
Hong Kong ◽  
Collective Memory ◽  
Digital Media ◽  
Political Communication ◽  
Civil Liberties ◽  
Significant Degree ◽  
Historical Period ◽  
Multiple Sources ◽  
News Reports ◽  
Wide Range

This book analyzes how collective memory regarding the 1989 Beijing student movement and the Tiananmen crackdown was produced, contested, sustained, and transformed in Hong Kong between 1989 and 2019. Drawing on data gathered through multiple sources such as news reports, digital media content, vigil onsite surveys, population surveys, and in-depth interviews with activists, rally participants, and other stakeholders, it identifies six key processes in the dynamics of social remembering: memory formation, memory mobilization, memory institutionalization, intergenerational transfer, memory repair, and memory balkanization. Memories of Tiananmen demonstrates how a socially dominant collective memory, even one the state finds politically irritable, can be generated and maintained through constant negotiation and efforts by a wide range of actors. While the book mainly focuses on the interplay between political changes and Tiananmen commemoration in the historical period within which the society enjoyed a significant degree of civil liberties, it also discusses how the trajectory of the collective memory may take a drastic turn as Hong Kong's autonomy is abridged. The book promises to be a key reference for anyone interested in collective memory studies, social movement research, political communication, and China and Hong Kong studies.

scholarly journals Production Process Effect on Mexican Agave Syrups Quality: A Preliminary Study

2018 ◽  
Vol 7 (3) ◽  
pp. 50
Author(s):  
Blanca I. Maldonado-Guevara ◽  
Sandra T. Martín del Campo ◽  
Anaberta Cardador-Martínez
Keyword(s):  
Production Process ◽  
Industrial Process ◽  
Quality Parameters ◽  
Thermal Hydrolysis ◽  
Process Variables ◽  
Anova Analysis ◽  
Hydroxymethyl Furfural ◽  
Wide Range ◽  
Preliminary Study

In this work, the quality parameters of commercial agave syrups produced in five different Mexican states and with different production process were evaluated. Regulated parameters (pH, Moisture, Ashes, and 5-(hydroxymethyl) furfural), as well as color and aw, were measured on 25 agave syrups, including traditional samples as controls. Traditional and semi-industrial syrups were samples obtained by thermal hydrolysis. Additionally, the semi-industrial process included control of process variables such as pH, °Bx, and temperature. The industrial process is technified. The agave syrups ranged from 70-76 °Bx, pH ranged from 3.2-6.7, and moisture from 20.2-28.6%. The aw values shown a wide variation as well as L* a* and b* color parameters. Some of those parameters shown significant differences in ANOVA analysis; however, most of the samples complied with the norm. General Discriminant Analysis (GDA) made it possible to discriminate between production process by using pH, % Ash, b*, 5-(hydroxymethyl)furfural and a* parameters. Further analysis of a wide range of syrups and the inclusion of non-regulated compounds such as volatile compounds and carbohydrates are needed to get more information for a deeper characterization of agave syrups. 

scholarly journals Modeling of trihalomethane compounds formation in Baghdad water supply network

2020 ◽  
Vol 29 (2) ◽  
pp. 136-144
Author(s):  
Salam Ewaid ◽  
Salwan Abed ◽  
Nadhir Al-Ansari ◽  
Bassam Al-Farhani
Keyword(s):  
Water Supply ◽  
Tap Water ◽  
Quality Parameters ◽  
Supply Network ◽  
Chromatography Method ◽  
Water Supply Network ◽  
Spss Software ◽  
Measured Water ◽  
Mean Concentration ◽  
Dependent Factor

This study was conducted to measure the concentrations of four trihalomethane compounds (THMs) in raw, treated, and drinking water of seven water purification plants and the residential neighborhoods nearby in Baghdad. About 350 samples gathered between January and October 2017 and analyzed by the gas chromatography method. Results showed that THM annual levels in tap water ranged between 12 and 97.3 μg·l–1 in winter and summer consecutively, with a mean concentration of 60 μg·l–1, these concentrations did not exceed the level recommended by the WHO and the Iraqi standards. Statistical modeling by SPSS software for the formation of THM (the dependent factor) in the water supply network was undertaken using the measured water quality parameters (as independent factors) and utilizing multiple regression analysis. The model obtained has a high correlation (r = 0.842) and approved that the most affecting parameters on THM formation are total organic carbon, temperature, turbidity, total solids, and chlorine dose. The model that was derived may be used for the purposes of choosing appropriate THM-reduction procedures and the use of chlorine for improving the method of disinfection.

Sign in / Sign up

Export Citation Format

Share Document