Economic significance and environmental impacts of the Song Dam Drinking Water Project(SDDWP)in Garhwal Himalaya

With the population growth through natural growth and migration,coupled with the city expansion,it is the fact that Dehradun City in India faces severe water scarcity.Therefore,the Song Dam Drinking Water Project(SDDWP)is proposed to provide ample drinking water to Dehradun City and its suburban areas.This paper examined economic significance and environmental impacts of the SDDWP in Garhwal Himalaya,India.To conduct this study,we collected data from both primary and secondary sources.There are 12 villages and 3 forest divisions in the surrounding areas of the proposed dam project,of which 3 villages will be fully submerged and 50 households will be affected.For this study,50 heads of the households were interviewed in the 3 submerged villages.The questions mainly focused on economic significance,environmental impacts,and rehabilitation issues of the dam project.The findings of this study indicate that economic significance of the dam project is substantial,including providing ample water for drinking and irrigation,contributing to groundwater recharge,creating job opportunities,and promoting the development of tourism and fisheries in the Doon Valley.In terms of the rehabilitation of the affected people,there are only 50 households in need of rehabilitation.Currently,the arable land of these affected people is not sufficient to sustain their livelihoods.The entire landscape is fragile,rugged,and precipitous;therefore,the affected people are willing to rehabilitate to more suitable areas in the Doon Valley.Moreover,it is essential to provide them with sufficient compensation packages including the compensation of arable land,houses,cash,common property resources,institutions,belongingness,and cultural adaptation.On the other hand,the proposed dam project will have adverse environmental impacts including arable land degradation,forest degradation,loss of fauna and flora,soil erosion,landslides,and soil siltation.These impacts will lead to the ecological imbalances in both upstream and downstream areas.This study suggests that the affected people should be given sufficient compensation packages in all respects.Afforestation programs can be launched in the degraded areas to compensate for the loss of forest in the affected areas.

Gross Alpha and Beta Activities and Related Lifetime Risks Assessment Due to Ingestion of Drinking Water from Different Sources in the District of Abidjan, Cote d’Ivoire

Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the objective of this study was to assess the risk of cancer due to the ingestion of alpha and beta emitting radionuclides in the different types of water consumed in the region. A total of 63 water samples with 43 tap water samples, 5 bottled mineral water and 15 sachet water samples was collected and taken to GAEC laboratory for analysis. The low background Gas-less Automatic Alpha/Beta counting system (Canberra iMaticTM) was used to determine alpha and beta activity concentrations. Activity concentrations of both gross alpha and gross beta obtained in water sample were respectively lower than the WHO recommended limits of 0.1 Bq/l and 1 Bq/l. Also, the annual effective dose and total equivalent effective dose found in mineral bottled water samples were higher than in other types of water. The assessment of radiological lifetime risk has shown values of cancer risk due to ingestion alpha and beta emitters lower than recommended limit. These results indicate that there is no health hazard associated to consumption of water in the District of Abidjan.

Assessment of Groundwater Quality for Drinking and Irrigation Uses in the Samba Dia Area, Central West Senegal

In the Sahelian zone in Africa, groundwater is the main source of drinking water for domestic, industrial, and agricultural uses. The groundwater of the Samba Dia sandy aquifer was assessed for understanding processes controlling the hydrogeochemistry and its drinking and irrigation suitability, on the basis of various water quality parameters. For the present study, thirty-three groundwater samples were collected in wells of the study area during the dry season in March 2021 and subjected to analysis for chemical characteristics (major ions), pH, electrical conductivity (EC), and total dissolved solids (TDS). Gibbs plot depicts that the process of ionic exchange is mainly due to the dissolution of water-rock interaction. The Piper diagram indicates a largely dominant sodium chloride facies with 70% of the groundwater samples followed by calcium chloride facies (18%) than calcium bicarbonate facies (12%). Analytical results of hydrogeochemical parameters of groundwater samples reveal that the majority of samples are within the World Health Organization safety range for drinking water. TDS and electrical conductivity (EC) values of groundwater indicate that 70% and 61% are safe for drinking water, respectively. Sodium percentage (% Na), Sodium Adsorption Ratio (SAR) values, and Ca/Mg ratio were calculated and compared with the standard guideline values recommended by the World Health Organization and agricultural water standards. This study shows that the groundwater in the area is mostly chemically suitable for drinking and irrigation, although some wells at the edge of the area exhibit signs of progressive salinization and traces of pollution.

The Effects of Energy Drink Consumption on Kidney and Liver Function: A Comparative Study

The current study aimed to investigate the potential health impacts associated with Energy Drink (ED) consumption and its effects on general health, liver function, and kidney function among students at Jazan University. EDs contain a variety of ingredients such as taurine, arginine, caffeine, acidity regulators, B vitamins, vitamin C, herbal extracts, and sugar. Previous studies have reported that EDs contain more caffeine content more a cup of coffee. Fifty-seven volunteer female students from the same socioeconomic background were eligible for the study based on their ED consumption habits. The students were divided into four groups: the control group (1) which did not consume EDs (19 students), group (2) which consumed 2 - 3 cans per week (19 students), group (3) which consumed 4 - 7 cans per week (14 students), and group (4) which consumed more than 7 cans per week (5 students). Five milliliters of venous blood were drawn from all subjects to determine ALT, AST, and GGT levels for liver function tests and creatinine, urea, uric acid, and BUN levels for kidney function tests. The results of the kidney function analysis showed that uric acid levels significantly increased (P 0.05) in all groups compared to the control group. The liver function analysis illustrated that, compared to the control group, only AST was significantly increased (P < 0.05) in groups 1 and 2. There was no significance in ALT and GGT in all groups. Overall, the study found that long-term ED consumption had a significant relationship to increased uric acid and AST concentrations, while urea and BUN decreased significantly. Further research is needed to understand the long-term health implications of ED consumption.

A review of physicochemical and biological contaminants in drinking water and their impacts on human health

Clean drinking water is one of the United Nations Sustainable Development Goals.Despite significant progress in the water purification technology,many regions still lack access to clean water.This paper provides a review of selected water contaminants and their impacts on human health.The World Health Organization(WHO)guidelines and regional standards for key contaminants were used to characterise water quality in the European Union and UK.The concept of safe drinking water was explained based on the non-observed adverse effect level,threshold concentrations for toxic chemicals,and their total daily intake.Various techniques for monitoring water contaminants and the drinking water standards from five different countries,including the UK,USA,Canada,Pakistan and India,were compared to WHO recommended guidelines.The literature on actual water quality in these regions and its potential health impacts was also discussed.Finally,the role of public water suppliers in identifying and monitoring drinking water contaminants in selected developed countries was presented as a potential guideline for developing countries.This review emphasised the need for a comprehensive understanding of water quality and its impacts on human health to ensure access to clean drinking water worldwide.

Comparative Effect of Adding Synthetic Citric Acid to Natural Lemon Juice (Citrus aurantiifolia) on the Stability of Hibiscus Drinks Stored at 4°C and 37°C

The general objective of the work is to compare the effect of the addition of synthetic citric acid compared to the addition of natural fruit juice of Citrus aurantiifolia on the conservation of drink based on red chalice H. sabdariffa. The tests were carried out over a period of 5 weeks at 4°C and 37°C with seven batches of beverage samples prepared at the rate of a calyx/water ratio of 1/40 (kg·kg-1) and added respectively citric acid at 1, 2 and 4 g·L-1 and lemon juice at 10, 20 and 40 mL·L-1. The characterization of the different batches of beverages was carried out from day one. A follow-up of the residual anthocyanin content and the intensity of the red coloring were carried out over five weeks. The anthocyanin concentration was determined by the pH-differential method. The red color degradation index is determined based on the CIELAB color system (L*, a*, b* and L*). R and Minitab 18 software was used for data processing. The results of the monitoring of the parameters showed that the concentration of 1 g AC L-1 retains 2.7 mg more of the anthocyanins than adding 10 mL JC L-1 and longer maintains red color when stored at 4°C and 37°C/5 weeks. The 2 g AC L-1 and 4 g AC L-1 ratios have the same effects as the addition of 20 and 40 mL of lemon juice, all accelerating the degradation of anthocyanins and the red color. After 5 weeks of storage at 37°C, the effect of the temperature combined with the increase in the acidity of the samples (2 to 4 g AC L-1 and 20 to 40 ml JC L-1), have accelerated the total disappearance of the red color on all samples.

Impact of the Condition of Drinking Water Supply Networks on the Quality of Water Intended for Consumption: The Case of the Network in the Commune of Daloa (Central West of Côte d’Ivoire)

The potability of drinking water depends not only on the source and the treatment system, but also on the quality of the waterworks. In fact, the quality of drinking water is considerably degraded by the dilapidated state and lack of maintenance of drinking water networks. In Côte d’Ivoire, the majority of drinking water networks in the various towns are ageing. In Daloa, despite the efforts made by the company in charge of water treatment and distribution to make the water drinkable, the water at consumers’ taps is often colored, has an unpleasant aftertaste and settles after collection. As a result, people are concerned about the potability of tap water, and some are turning to alternative sources of drinking water of unknown quality. In order to determine the factors responsible for the deterioration in water color and taste, as well as the sectors of the network most affected, a diagnosis of the network’s equipment was carried out. Water samples taken from the network were analyzed for color and turbidity. The diagnosis revealed that most of the equipment (suction pads, valves, drains and fire hydrants) is outdated and irregularly maintained. Analyses show that the water is more colored in cast-iron and PVC pipes than in asbestos cement pipes. Coloration values in the network range from 0 to 27 UVC for asbestos cement pipes, from 15 to 56 UCV for ductile iron pipes, and from 11 to 102 UCV for PVC pipes. On the over hand, turbidity values vary from 8.02 to 3.32 NTU for ductile cast iron pipes, 8.51 to 16.98 NTU for asbestos cement pipes and 0.9 to 6.98 NTU for PVC pipes. Old cast-iron pipes release ferric ions on contact with water, degrading their color. Old cast-iron pipes release ferric ions into the water, degrading its color. The high color values observed in the vicinity of drains are thought to be due to irregular maintenance of the network. In fact, after network maintenance, a reduction rate ranging from 2% to 73% is observed for turbidity, while for color, the rate varies from 5% to 72%. In short, the network’s obsolescence and irregular maintenance contribute significantly to the deterioration of water quality.

Study on the Possibility of Raw Seawater into Drinking Water—A Religious Water Literacy

This paper explores the conversion of raw seawater into drinking water from a religious water literacy (RWL) perspective. RWL is here defined as a socially just water literacy that is based on the respect for the dignity of life of all living beings on the Earth. It discusses the importance of sustainable water sources and proposes purification methods. That is, the study aims to show a brief outline of the drinking water source (inland waters;mainly river water) and their purification technologies in recent times and today and propose the purification method (Freezing-Thawing-UV method) in case of taking the seawater as the source. And, it emphasizes the need for dialogue and cooperation between countries in order to proceed. The paper also discusses the relationship among religion, culture, and civilization, and highlights the similarities between Marx’s historical materialism and Umesao’s ecological view. It further discusses the importance of water purification technology, separation methods, and the potential for seawater as an energy source. The paper concludes by discussing the importance of dialogue, communication and understanding environmental decision-making. In order to carry them forward, it is convinced that citizens in the world are nothing but people with self-awareness of “Bodhisattvas of the Earth” as identities. As a result, the new findings that suggest the possibility of raw seawater into drinking water from a religious water literacy perspective through the lens of Kawakatsu’s maritime view have been obtained.

Legislation on protection of drinking water sources and local management practices in the Pearl River Delta region of China

The protection of drinking water sources is vital to urban development and public health.In this study,the current situation of the mandatory protection area for drinking water source in the Pearl River Delta region was investigated using a method combining Google Earth with the field survey.The gaps between management practices and legislation requirements were analyzed.Finally,several countermeasures for water resource protection were proposed as follows:to promote delineation in a more scientific way,to safeguard the sanctity of the law,to make better plan on water saving,and to encourage public participation in supervision and management.

Association between soft drink consumption types and risk of lung cancer and all-cancer: A prospective study of PLCO data

Diet/sugar-free soft drinks are considered to be healthier than regular soft drinks.However,few studies have examined the relationship between the types of soft drinks(regular and diet/sugar-free)and lung cancer(LC)/all-cancer(AC)risk.In this study,we comprehensively assessed the influence of the type of soft drink consumption on LC/AC risk based on the Prostate,Lung,Colorectal,and Ovarian(PLCO)Cancer Screening Trial.Multivariable Cox proportional hazards and competing risks Fine-Gray regression models adjusted for relevant confounders were used to estimate hazard ratios(HRs)and subdistribution HRs for different types of soft drink consumption.In the PLCO population,female subgroup,and the ever/current smoker subgroup,consumption of both regular and diet soft drinks was associated with a significantly reduced risk of LC compared with no soft drinks at all.For the non-lung cancer(NLC)risk,consumption of only diet soft drinks had a significant positive association for the total population and female subgroup.Based on our findings,it was suggested that partial replacement of regular soft drinks with diet soft drinks might be beneficial to LC prevention,especially for females and ever/current smokers.Additionally,completely replacing regular soft drinks with diet soft drinks might be detrimental to NLC prevention,especially for females.

Effects of a Revised Moderate Drinking Program for Enhancing Behavior Modification in the Workplace for Heavy Drinkers: A Randomized Controlled Trial in Japan

This study examined the effects of the Hizen Alcoholism Prevention Program (HAPPY) and the revised version of HAPPY (HAPPY Plus), and also compared the two programs to determine whether the HAPPY Plus achieved better outcomes for heavy drinkers in the workplace. The HAPPY Plus designed to strengthen participants’ recruitment, perception of threat, stress management, behavior modification by self-monitoring using a calendar-based diary, and to prevent dropout by telephone and e-mail follow-up by a trained nurse. Participants were men and women who consumed at least 20 g and 10 g of alcohol daily, respectively, and had not been diagnosed with alcohol dependence. A group intervention, 3-month randomized controlled trial was conducted. The control and intervention groups received the HAPPY and HAPPY Plus, respectively. The primary endpoint was average daily alcohol consumption. The Alcohol Use Disorders Identification Test (AUDIT), weight, body mass index, blood pressure, liver function, goal achievement rate, self-efficacy, and self-esteem were also measured. Out of 88 recruited employees, 83 (intervention group: 40;control group: 43) completed the study (completion rates were 100% and 93.4% respectively). As a result, average daily alcohol consumption decreased significantly in both groups (p < 0.001), but did not differ between groups. Even though behavior change rate was higher, and self-efficacy and confidence increased in the intervention group, AUDIT decreased in both groups but was significant only in the control group. Physiological indicators in the intervention group improved, but were not significant between the groups. Against the program revision, this study did not prove superiority of HAPPY Plus to the HAPPY regarding the indicators. However, better behavior modification and lower dropout were observed in the HAPPY Plus. Therefore, after further improvement is made, this group intervention program is applied to the workplace.

Violent and Risk-Taking Behaviors Associated with Intake of Energy Drinks Mixed with Alcohol and Perceptions of This Consumption among Children and Adolescents in Costa Rica

Introduction: The consumption of energy drinks and its mix with alcohol has been associated with negative and violent behaviors in youngsters. Objective: To determine the risk-taking behaviors associated with the consumption of energy drinks mixed with alcohol in Costa Rican adolescents. Methods: A mixed cross-sectional study was performed with a population of 2667 students of 64 educative centers in 2016. Descriptive statistics were performed with the program SPSS 20.0 and a value of p < 0.05 was considered significant. Results: The third part of the study population is usually a consumer of energy drinks (30%) and 3% make use of drinks mixed with alcohol. The children and adolescents, who consume energy-alcohol mixed drinks, are more likely to present risk-taking behaviors than those who do not consume these mixed beverages: combined use of medicines to get high;cocaine consumption, consumption of cement/glue, consumption of marijuana, physical violence (fighting), use of weapons, suicidal ideation, deliberate self-harm, low educational expectation, sexual intercourses, cyberbullying and school apathy. The students perceived the intake of energy beverages as of low risk for their health. They also agree that frequent consumption is because drinks have good flavors and nice logo designs and the ability to stay awake and with more energy for longer periods of time in order to improve in academic homework, sports performance and to endure more the consumption of alcoholic beverages. Conclusions: Public health policies should consider controlling the publicity aimed to children and adolescents regarding the marketing of energy and alcoholic drinks.

Effects of energy and sports drinks on tooth structures and restorative materials

Sports and energy drinks are consumed by more peoplethan ever. Sports and energy drinks may enhance physical resistance, stimulate metabolism, prevent rehydration and replace electrolytes during high activity efforts. However, these drinks often have a low pH and are acidic, which can erode enamel and dentin, and increase dentine hypersensitivity. In addition to the adverse effects of sports and energy drinks on tooth structures, they often have the potential to damage restorative materials. These drinks often contain artificial colors which have potential to discolor resin composite materials and glass ionomers. The acidic nature of these drinks could also lead to a degradation, increase in wear, and roughening of the surface of the restorative materials. Many of the negative consequences of sport and energy drinks can be related to their overconsumption among children and teenagers. Patients should be advised to have a healthy diet, and consume soft and energy drinks in moderation, to avoid any negative dental or health consequences. The overconsumption of sports and energy drinks which are high in sugar and have the lowest pH are most likely to cause avoidable dental problems.

Gastric cancer risk in relation to tobacco use and alcohol drinking in Kerala, India-Karunagappally cohort study

AIM: To assess the risk of gastric cancer(GC) in relation to tobacco use and alcohol drinking in the Karunagappally cohort in Kerala, South India.METHODS: This study examined the association of tobacco use and alcohol drinking with GC incidence among 65553 men aged 30-84 in the Karunagappally cohort. During the period from 1990-2009, 116 GC cases in the cohort were identified as incident cancers. These cases were identified from the populationbased cancer registry. Information regarding risk factors such as socioeconomic factors and tobacco and alcohol habits of cohort members were collected from the database of the baseline survey conducted during 1990-1997. The relative risks(RRs) and the corresponding 95% confidence intervals(95%CIs) fortobacco use were obtained from Poisson regression analysis of grouped survival data, considering age, follow-up period, occupation and education.RESULTS: Bidi smoking was associated with GC risk(P = 0.042). The RR comparing current versus never smokers was 1.6(95%CI: 1.0-2.5). GC risk was associated with the number of bidis smoked daily(P = 0.012) and with the duration of bidi smoking(P = 0.036). Those who started bidi smoking at younger ages were at an elevated GC risk; the RRs for those starting bidi smoking under the age of 18 and ages 18-22 were 2.0(95%CI: 1.0-3.9) and 1.8(95%CI: 1.1-2.9), respectively, when their risks were compared with lifetime non-smokers of bidis. Bidi smoking increased the risk of GC among never cigarette smokers more evidently(RR = 2.2; 95%CI: 1.3-4.0). GC risk increased with the cumulative amount of bidi smoking, which was calculated as the number of bidis smoked per day x years of smoking(bidi-year; P = 0.017). Cigarette smoking, tobacco chewing or alcohol drinking was not significantly associated with GC risk. CONCLUSION: Among a male cohort in South India, gastric cancer risk increased with the number and duration of bidi smoking.

Drinking water production by uitrafiltration of Songhuajiang River with PAC adsorption

In recent years, membrane ultrafiltration （UF） of surface water for drinking water treatment has become a more attractive technology worldwide as a possible alternative treatment to conventional clarification. To evaluate the performance of ultrafiltration membranes for treatment of surface water in North China, a 48-m^2 low pressure hollow fiber membrane ultrafiltration pilot plant was constructed. Ultrafiltration was operated in cross-flow and with powdered activated carbon （PAC） adsorption. Turbidity was almost completely removed to less than 0.2 NTU （below Chinese standard 1 NTU）. It was found that PAC addition enhanced organic matter removal. The combined process of PAC/UF allowed to 41% removal of CODMn, 46% removal of DOC and 57% decrease in UV254 absorbance. The elimination of particles, from average 12000/ml in the raw water to approximately 15/ml in the permeated, was observed. When PAC concentration was below 30 mg/L, backwashing could recovery the membrane flux with backwash interval/backwashing duration of 1/30.

Soft drinks consumption and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease(NAFLD) is a common clinical condition which is associated with metabolic syndrome in 70% of cases.Inappropriate dietary fat intake,excessive intake of soft drinks,insulin resistance and increased oxidative stress combine to increase free fatty acid delivery to the liver,and increased hepatic triglyceride accumulation contributes to fatty liver.Regular soft drinks have high fructose corn syrup which contains basic sugar building blocks,fructose 55% and glucose 45%.Soft drinks are the leading source of added sugar worldwide,and have been linked to obesity,diabetes,and metabolic syndrome.The consumption of soft drinks can increase the prevalence of NAFLD independently of metabolic syndrome.During regular soft drinks consumption,fat accumulates in the liver by the primary effect of fructose which increases lipogenesis,and in the case of diet soft drinks,by the additional contribution of aspartame sweetener and caramel colorant which are rich in advanced glycation end products that potentially increase insulin resistance and inflammation.This review emphasizes some hard facts about soft drinks,reviews fructose metabolism,and explains how fructose contributes to the development of obesity,diabetes,metabolic syndrome,and NAFLD.

Relationship Between Microcystin in Drinking Water and Colorectal Cancer

Objective To investigate the association of microcystin (MC) in drinking water with the incidence of colorectal cancer. Methods The study was designed as a retrospective cohort. Eight townships or towns were randomly selected as the study sites in Haining City of Zhejiang Province, China. 408 cases of colon and rectum carcinomas diagnosed from 1977 to 1996 in the study sites were included, and a survey on types of drinking water of these patients was conducted. Samples of different water sources (well, tap, river and pond) were collected separately and microcystin concentrations were determined by indirect competitive ELISA method. Results The incidence rate of colorectal cancer was significantly higher in population who drank river and pond water than those who drank well and tap water. Compared to well water, the relative risk (RR) for colorectal cancer was 1.88 (tap), 7.94 (river) and 7.70 (pond) respectively. The positive rate (>50 pg/mL) of microcystin in samples of well, tap, river and pond water was 0, 0, 36.23% and 17.14% respectively. The concentration of microcystin in river and pond water was significantly higher than that in well and tap water (P<0.01). Spearman rank correlation analysis showed that in the study sites, the microcystin concentration of river and pond water was positively associated with the incidence of colorectal cancer (rs= 0.881, P<0.01). Conclusions The types of drinking water are positively associated with the incidence of colorectal cancer in the study sites, and this may be related to microcystin contamination of drinking water. Further biological study is needed to support the possible causative role of mycrocystin in carcinogenesis of colon and rectum.

Particle properties in granular activated carbon filter during drinking water treatment

The elemental composition and bacteria attached in particles were investigated during granular activated carbon （GAC） filtration.The experimental results showed that trapped influent particles could form new,larger particles on GAC surface.The sloughing of individuals off GAC surface caused an increase in effluent particles in the size range from 5 to 25 μm.The selectivity for element removal in GAC filters caused an increasing proportion of metallic elements in the effluent particles.The distribution of molar ratio indicated a complicated composition for large particles,involving organic and inorganic substances.The organic proportion accounted for 40% of total carbon attached to the particles.Compared with dissolved carbon,there was potential for the formation of trihalomethanes by organic carbon attached to particles,especially for those with size larger than 10 μm.The pure carbon energy spectrum was found only in the GAC effluent and the size distribution of carbon fines was mainly above 10 μm.The larger carbon fines provided more space for bacterial colonization and stronger protection for attached bacteria against disinfection.The residual attached bacteria after chorine disinfection was increased to 10 2-10 3 CFU/mL within 24 hours at 25°C.

Genotoxicity evaluation and a primary risk assessment of organic pollutants in the drinking water sources of Nanjing, China

An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In this study, the comet assay was conducted to investigate the genotoxicity to human body caused by organic concentrates in the drinking water sources of Nanjing City from Yangtze River of China, and health and ecology risk due to expose to these organic pollutants were evaluated with the multimedia environmental assessment system （MEAS）. For all the water samples, they were collected from four different locations in the drinking water sourcr samples, es of Nanjing City. The results of the comet assay showed that all the organic concentrates from the water samples could induce different levels DNA damages on human peripheral blood lymphocytes, and a statistically significant difference （p〈0.01） was observed compared with the solvent control, which demonstrated the genotoxicity was in existence. According to the ambient severity （AS） of individual compound, we had sorted out the main organic pollutants in the drinking water source of the four waterworks, and the results showed that there was some potential hazard to human body for all the source water, namely the total ambient severity （TAS） of health for each water source was more than 1. However, the TAS of ecology for each water source was less than 1, which indicated that it was safe to ecology. The results of this investigation demonstrate the application of the comet assay and the MEAS in aquatic environmental monitoring studies, and the comet assay found to be fast, sensitive, and suitable for genotoxicity monitoring programs of drinking water source.

Effects of fulvic acid and humic acid on aluminum speciation in drinking water

This article focused on the influences of fulvic acid and humic acid on aluminum speciation in drinking water. Factors including the concentration of residual chlorine and pH value had been concerned. Aluminum species investigated in the experiments included inorganic mononuclear, organic mononuclear, mononuclear, polymer, soluble, and suspended forms. It was found that the effects of fulvic acid and humic acid on aluminum speciation depended mainly on their molecular weight. Fulvic acid with molecular weight less than 5000 Dalton had little influence on aluminum speciation; while fulvic acid with molecular weight larger than 5000 Dalton and humic acid would increase the concentration of soluble aluminum significantly even at concentration below 0.5 mg/L （calculated as TOC）. Aluminum species, in the present of fulvic acid with molecular weight larger than 5000 Dalton and humic acid, were more stable than that in the present of fluvic acid with molecular mass less than 5000 Dalton, and varied little with reaction time. Within pH range 6.5-7.5, soluble aluminum increased notably in water with organic matter. As the concentration of residual chlorine increased, the effects of fulvic acid and humic acid became weak. The reactions between humic acid, fulvic acid with large molecular weight, and aluminum were considered to be a multi-dentate coordination process. With the consideration of aluminum bioavailability, reducing the concentration of fulvic acid and humic acid and keeping the pH value among 6.5-7.5 were recommended during drinking water treatment.