Mean Total Dissolved Solids Research Articles

Study of the dyeing industry pollution after mandatory installation of ETP in Madhabdi municipality, Bangladesh

ABSTRACT Madhabdi municipality of the Narsingdi district of Bangladesh, the “Manchester of the East,” is famous for its cloth market and fabric dyeing industries. The untreated effluent discharge has been mixed with the water and soil, degrading the environmental standards of this area for years. Installing an effluent treatment plant (ETP) in all textile industries in Bangladesh is mandatory. This study evaluates the soil condition, surface water quality, and heavy metal contamination in cultivated vegetables after the compulsory installation of ETP. Soil and water samples from eight locations and cultivated vegetable samples from three locations are collected and analyzed for this study. The pH, EC (electric conductivity), TDS (total dissolved solids), DO (dissolved oxygen), and heavy metal concentrations are observed. The water quality index, contamination index, metal evaluation index, pollution load index, and metal pollution index are calculated from the collected samples. The study found that the physico-chemical properties of water pH (9.19), EC (2232.38 µScm-1), and DO (0.79 mgL-1) violate the national standards. The mean TDS is below the maximum permissible level. The heavy metal concentrations of Cr and Pb in water are 1.03 and 0.13 mgL-1, crossing the permissible limit, respectively, but Mn, having 0.89 mgL-1, is within the limit. The water quality is unsuitable for domestic and agricultural use, contamination is “medium,” and metal evaluation is “medium.” The soil is alkaline, having a pH of 8.58. The soil’s Cr, Pb and Mn concentrations are 68.21 µgg-1, 52.73 µgg-1and 805.16 µgg-1, respectively. The soil contamination level is low to moderate. Cultivated leafy vegetables have a concentration of Cr, Pb and Mn; 2.61 µgg-1, 0.30 µgg-1and 288.67 µgg-1, respectively, where Cr has crossed, Pb is within, and Mn is lower than the permissible limit. Produced vegetables have high (12.10–33.09) MPI (metal pollution index) and are at a high-risk level for consumption as food.

Water quality assessment of Kuwano River, Basti (U.P.) India, with reference to statistical analysis

The present study analyses water quality parameters in the Kuwano River, Basti district, using correlation and regression analysis to establish relationships between variables and provide a comprehensive understanding of the factors influencing water quality. Kuwano is the main river that flows through Basti city. The water samples were collected at three locations. The values of different physicochemical parameters of the river water sample were found to be dependent on the hydrology of the area. The pH was strongly associated with TDS (r = 0.885), DO (r = 0.744), COD (r = 0.969), TH (r = 0.806), and Mg (r = 0.944). The biological oxygen demand (BOD) (-0.345), nitrate (-0.235), and calcium (-0.128) exhibited an inverse correlation with total dissolved solids (TDS), whereas nitrate and calcium had a positive correlation with all other physicochemical parameters. The mean TDS value of the river water sample (81.2) was within the permissible limit for drinking water. The total coliform counts established a negative correlation with most of the parameters studied, e.g., dissolved oxygen (-0.628), BOD (-0.983), chemical oxygen demand (-0.194), total hardness (-0.549), nitrate (-0.955), Ca (-0.918) and Mg (-0.279). The study's findings may provide practical information for decision making in river pollution management.

Hydrochemical characteristics and suitability of Kanzenze River for irrigation of akagera upper catchment in Rwanda

The purpose of the study was to assess the hydrochemical characteristics of the Kanzenze River and its suitability for irrigation use in the Akagera upper catchment in Rwanda. In this respect, 12 samples of surface collected water in four sites namely Karumuna, Muzi, Karugenge, and Nyamabuye were at a distance of 100.00 meters one to another. The Food and Agriculture Organization (FAO) standards were referred to analyze water quality parameters such as potential hydrogen (pH), electrical conductivity (EC), total dissolved solids (TDS), sodium adsorption ratio, soluble sodium percent, total hardness, magnesium adsorption ratio and Kelly index were used for the evaluation of water quality and its suitability for irrigation. Data were analyzed using descriptive analysis and principal components analysis. All parameters analyzed were within the FAO standards stipulated for irrigation. The mean pH of the water sample was 7.30; the mean TDS was 205.10 mg l‒1; mean sodium adsorption was 2.30 while the mean EC was 302.26 µS/cm which indicated that Kanzenze River is in category I of classification standard suitable for irrigation. This indicated that the Kanzenze River was suitable for irrigation.

Water Quality Assessment and Spatial Variation in Aba River Water, South-Eastern Nigeria

The status of the Aba freshwater ecosystem (river) was assessed for the influence of human activities at differentsections of the river and its attendant effects on water parameters. To achieve this, samples of water were collected monthly from January to June 2020 at three sampling stations marked A1, A2, and A3 and were analysed on-site for water, electrical conductivity (EC), dissolved oxygen (DO), pH, salinity, total dissolved solids (TDS) and temperature with the aid of a handheld multi-parameter kit. Biochemical oxygen demand (BOD) was fixed onsiteand taken to the laboratory along with samples for potentially toxic metals (PTMs), Cd, Cu, Pb, Fe, and Zn),which were analysed by standard analytical procedure.Statistical variation across the sampling hotspots was determined with a one-way analysis of variance. The results indicated the average values of pH were moderately low in all the stations with little statistically variation (p˃ 0.05) between samples. The mean EC indicated station A1 (1394.32±152) had the highest concentration, followed by station A2 (972.14±52.22), and A3 (496.16±72.10) was the lowest. The mean salinity, TDS and Cl- followed a similar pattern as EC, with significant differences (p ˂ 0.05) in all the stations. DO values for A3 (4.90±0.37) were the highest while for A1 (3.34±0.21) they were the least. The mean BOD results for station A1 (6.54±5.54) were the highest whereas for A3 (3.28±0.66) they were the lowest. The value of metals across the stations indicated higher occurrence pattern: Fe˃ Zn ˃Cu˃ Cd˃ Cr˃ Pb. Generally, the concentrations of physicochemical and potentially toxic metal parameters were above the threshold for surface water and this deduced that the river was contaminated and needed urgent remediation. Also, the government should regulate the discharges of industrial effluents, agricultural wastes and sewage into the water body to safeguard the river from further deterioration.

Water Quality Index classification of ground water samples collected from Opete, community, Delta State, Southern Nigeria

The overall quality of groundwater samples collected from different sampling points in Opete Community, Delta State was evaluated using Water Quality Index (WQI) assessment. Ten ground water samples abstracted in duplicates were obtained from 10 sampling points in various areas within Opete. Selected physico-chemical evaluation of the water samples was conducted using standard techniques. The parameters were; Electrical conductivity (EC), pH, dissolved oxygen (DO), total hardness, total alkalinity, total dissolved solids (TDS), magnesium and calcium. All the water samples were acidic as the pH values ranged from 3.20 to 6.00. The mean TDS readings varied from 9.80 mg/L to 134.50 mg/L. The water quality index values obtained ranged from 34.506 to 69.44. The WQI classification of water samples collected from sampling point (SP) 3 and 10 was bad while samples sourced from SP 2,4,5,6,7,8 and 9 were of medium quality. Although the results indicated the unsuitability of the sampled ground water for direct anthropogenic consumption, the water is suitable for conducting domestic chores such as sanitation activities.

Evaluation of Surface Water Quality Using Various Indices for Heavy Metals in Sasolburg, South Africa

The purpose of the study was to determine the concentrations of heavy metals in surface waters used for domestic and farming activities. This study investigated various water quality parameters, including pH, electrical conductivity (EC), total dissolved solids (TDS), and major and trace elements such as Al, As, Cd, Co, Cr, Fe, Mn, Mo, Ni, Pb, Sb, Se, Sr, Tl, and V, which were investigated during the dry and wet seasons from samples collected at Meulsteenpan Lake, Coalplex Stream, and Natref Stream in Sasolburg, Free State, South Africa (2019–2020). The results revealed that the pH of water collected from Meulsteenpan Lake (7.86–7.89) and Coalplex stream (7.13–7.37) were within the Department of Water Affairs and Forestry (DWAF), World Health Organization (WHO), and Environmental Protection Agency (EPA) permissible guideline values for domestic and agricultural use. On the other hand, the pH from Natref stream (6.16–7.68) was within the permissible guideline values set by the DWAF for domestic use but below the permissible guideline values set by the WHO and EPA for domestic use, and the DWAF for agricultural use. The mean TDS and EC values in Meulsteenpan Lake (796–980 mg/L) and (1.20–2.00 mS/m) exceeded permissible guideline values set by the DWAF and WHO domestic use for TDS, Coalplex stream (309–326 mg/L) and (0.65 mS/m), and Natref Stream (269–413 mg/L) and (0.89–0.96 mS/m) were within the permissible guideline values for the DWAF and WHO domestic use for TDS. The results obtained for metal concentration revealed higher mean concentrations for Al, Fe, and Mo, Mn in the study area, which could pose adverse health risks to aquatic life and humans. Various pollution and health assessments (Cf, m-Cd, m-HPI, HEI, NEI, and WQI) were used to evaluate the quality status of the surface water on all sampling sites. WQI revealed that in the wet and dry seasons, surface waters from Coalplex Stream and Natref Stream had “excellent” water quality, while Meulsteenpan Lake had “excellent” water quality in the dry season, but in the wet season, the water quality was “unsuitable for drinking”.

Investigation of Corrosion and Scaling Potential in Drinking Water in Rafsanjan, Iran

Introduction: Corrosion and scaling are important factors affecting drinking water quality, causing health and economic problems. This study aimed to investigate the indicators of corrosion and scaling in Rafsanjan drinking water.
 Materials and Methods: The present descriptive cross-sectional study was conducted in winter 2018 and spring 2019 in Rafsanjan. The 56 samples were randomly taken from the drinking water distribution and transmission networks. Physicochemical parameters, such as pH, temperature, total dissolved solids (TDS), total hardness (TH), calcium hardness (CH), electrical conductivity (EC), and alkalinity were measured. Finally, corrosion and scaling indices, including langelier index (LI), ryznar index (RI), aggressiveness index (AI), and Puckorius index (PI) were calculated and analyzed.
 Results: The mean temperature, pH, CH, TH, TDS, alkalinity, and EC were 17.79 ± 0.80 °C, 8.08 ± 0.11, 56.34 ± 2.72 mg/L.CaCO3, 140.86 ± 6.81 mg/L.CaCO3, 530 ± 110 mg/L, 181.21 ± 13.65 mg/L, and 840 ± 180 µs/cm, respectively. The mean corrosion and scaling indices, including LI = 0.18 ± 0.12, RI = 7.72 ± 0.14, AI = 12.09 ± 0.11, and finally PI = 7.96 ± 0.10 were obtained.
 Conclusion: Based on the obtained data, drinking water in the transmission and distribution network of Rafsanjan has scaling properties. Water scaling and deposition causes problems, such as blockage of water transmission and distribution pipes, reduction of flow rate and increase of pressure drop in the network, and finally increase of water facilities operation costs. Therefore, measures should be considered to control the scaling of water in this region.

Groundwater Quality Assessment of Ikorodu Local Government Area of Lagos State in Nigeria

An assessment of the quality of groundwater in Ikorodu Local Government Area (LGA) was carried out in September 2020 (Late wet season). A total number of 29 samples were collected from different selected locations of the study area. The samples were collected from private and government bore holes. The pH, Total dissolved solids (TDS), Salinity, Turbidity, Hardness, Biochemical oxygen demand (BOD), Chemical oxygen demand (COD), Phosphate, Nitrate, Sulphate, and Total bacterial count (TBC) were determined according to American Public Health Association (APHA) standard techniques. The results showed that the mean pH, TDS, Salinity, Turbidity, Hardness, BOD, COD, Phosphate, Nitrate, Sulphate, and TBC in the water samples were 7.0 ±0.59, 176.0 ±132.2mg/L, 0.14 ±0.11g/kg, 0.32 ±0.05 NTU, 59.58 ±34.89mg/L, 11.59 ±3.41mg/L, 14.90 ±4.18mg/L, 0.97 ±0.46mg/L, 2.62 ±1.27mg/L, 9.44 ±5.94mg/L, and 4.92 ±2.94 x 102 cfu/mL, respectively. The calculated Water quality index (WQI) of the different sampling points showed the least WQI was 50.3 and the highest WQI was 66.9. Overall, the WQI indicated “Poor” quality of groundwater in the Ikorodu Local Government Area of Lagos State.

Prediction of SAR and TDS parameters using LSTM- RNN model: A case study on Aran station, Iran

Surface water quality is of particular importance due to its drinking, industrial, and agricultural water sources. Changes in rainfall, temperature and river discharge can affect surface water quality. In this study, the effect of CANESM2, FIO, GFDL, MIROC climate models and weight composition model of CMIP5 (Coupled Model Intercomparison Project) under representative concentration pathways (RCP) of 4.5, 6, 8.5 scenarios on rainfall and temperature were investigated and then monthly discharge of the Aran River in Iran during 2020-2052 and 2053-2085 is predicted using the IHACRES runoff model. Next, the LSTM (Long Short-Term Memory network)-RNN (Recurrent Neural Networks) model were used to predict the total dissolved solids (TDS), Sodium adsorption ratio (SAR) rate for the period 2020-2030. The results showed that the long-term monthly rainfall under the RCP8.5 scenario reported a further decrease compared to the RCP4.5 and RCP6, and the rainfall fluctuations were higher than the other two scenarios. Temperature changes in the second period are higher than in the first period, so that in the first period under the scenario of RCP4.5, RCP6 and RCP8.5 showed respectively 1, 1.5 and 2 degrees Celsius increase, while in the second period, 2, 3 and 4 degrees Celsius is predicted. The average discharge shows by 15.8% and 20.97% respectively decrease under the RCP4.5 scenario in the first and second periods, while by 8.51 and 27.55% under the RCP6 scenario and 6.38% and 39.89% under the RCP8.5 scenario compared to the observed discharge. The mean, maximum, and minimum TDS parameters under RCP4.5 scenario are, respectively, 295, 410, and 263, and 302, 410, and 257 under RCP6 scenario while 292, 410, and 257 mg, for RCP8.5 scenario. These changes are, respectively, 0.42, 0.93 and 0.14 for the SAR parameter in RCP4.5 scenario, and equal to 0.44, 0.94 and 0.1 in scenario 6, while 0.42, 0.93 and 0.15, respectively, for RCP8.5 scenario in Khorramrood River.

Hydrochemical and radiometric evaluation of fresh and thermal waters from Araxá city (Minas Gerais, Brazil).

This paper reports the hydrochemistry and activity concentration of the natural radionuclides 238U, 234U, and 210Po for three compartments of the hydrological/hydrogeological system in Araxá city, Minas Gerais State, Brazil: 1) mineral waters from the prominent springs Dona Beja (DBS) and Andrade Júnior (AJS), occurring at Barreiro area; 2) surface waters from Barreiro area and vicinity; and 3) rainwater. According to the Rule for Mineral Waters in Brazil (Register 7841) for temperature, the DBS water is cold (< 25°C), while AJS is hypothermal (25-33°C). The TDS (Total Dissolved Solids) concentration of DBS is low (70mg/L), but high in AJS (2898mg/L). The hydrogeochemical facies corresponded to sodium-(bi)carbonate for AJS and sodium/potassium-bicarbonate for DBS. The hydrochemical differences of DBS and AJS waters reflect the distinct characteristics of their respective aquifer systems. The DBS classification for TDS is the same of the Barreiro basin surface waters (mean TDS = 102mg/L). Such value is somewhat higher than that of the rainwater and surface waters used for human consumption at Araxá city (TDS < 50mg/L). The dataset reported in this paper indicated that fluoride and barium exceeded the WHO limits proposed in 2011 for drinking water. Among the natural radionuclides analyzed here that offer potential hazards for the human health is 210Po, whose WHO's limiting value of 100mBq/L in drinking water was exceeded in rainwater, thus, restricting the use of this resource as a possible supply of drinking water for the local community.

Investigating use of chlorine dioxide for pre-treatment of raw water from polluted sources at Morton Jaffray Water Treatment Works, Harare, Zimbabwe

Abstract Raw water quality deterioration has affected capabilities of Conventional Water Treatment Processes (CWTP) in many countries. CWTP used at Morton Jaffray Water Treatment Works (MJWTW) in Harare have proven ineffective due to pollution. The study investigated the use of chlorine dioxide (ClO2) as an alternative pre-treatment chemical. Its effectiveness was compared to that of calcium hypochlorite (Ca(CIO)2) used at MJWTW. Grab raw water samples from MJWTW were collected between January and March 2020 and pre-treated with ClO2 and Ca(CIO)2 followed by jar tests with alum to determine pre-treatment effectiveness. Parameters analyzed included electrical conductivity (EC), total dissolved solids (TDS), total solids (TS), turbidity, chemical oxygen demand (COD), pH and total algae counts (TAC). The raw water had mean TDS (264 mg/L), TS (440 mg/L), turbidity (7.1 NTU), COD (85 mg/L), pH (7.9) and TAC (28.4 × 106 cells/mL). The optimum alum dosage without pre-oxidation was 80 mg/L. Pre-oxidation with 0.075 mg/L ClO2 reduced alum dosage to 60 mg/L. This ClO2 dosage was compared to a Ca(CIO)2 dosage of the same concentration and strength at 5 and 15-minutes contact time before alum dosage at 60 mg/L. The treated water quality parameter levels proved better performance for ClO2 compared to calcium hypochlorite.

Effects of Salt Harvesting on Ground Water Quality in Gongoni Ward, Kilifi County, Kenya

Aims: To determine the effects of salt harvesting on ground water quality in Gongoni ward, Kilifi County.&#x0D; Study Design: The study design was purposive where sampling points were deliberately chosen.&#x0D; Place and Duration of Study: The study was carried out in Gongoni ward and its environs in Kilifi County from May 2015 to July 2015.&#x0D; Methodology: Sixteen sampling points were selected within the study area and sampling was done twice between May and July 2015. The water samples collected were analyzed for sodium (Na+), Chlorides (Cl-), Fluorides, (F-) Calcium (Ca2+), alkalinity, acidity (pH), E. coli, Total Dissolved Solids (TDS) and Salinity as NaCl in the Government Chemist laboratories in Mombasa. The collected data was analyzed using SPSS and Microsoft Office Excel.&#x0D; Results: The ground water sources in Gongoni ward registered high levels of key parameters (TDS, Salinity, Chloride, and Sodium) than the adjacent areas of Mambrui, Ngomeni and selected secondary data from Mombasa County wells where no salt harvesting occurs. Gongoni water sources had a mean TDS of 1969.00mg/L and the adjacent area shad TDS of 1050.00 mg/L. The level of E. coli and total coliform were above the Kenyan and WHO permissible limit of 0 MPN/100ml for treated water and 10 MPN/100mls for untreated water.&#x0D; Conclusion: Despite the elevated concentration levels of chemical parameters from Gongoni ward water sources, the differences are not statistically significant when compared to the adjacent areas of Mambrui and Ngomeni.&#x0D; Recommendations: The water from sources with high levels of TDS and salinity should be pre-treated to make the water more suitable for human use. Those with high coliform and E. coli bacteria should be regularly treated using the appropriate disinfection methods. It is recommended that all projects on salt harvesting should be subjected to an Environmental and Social Impact Assessment (ESIA) before implementation as provided by the Kenya Environmental Management and Coordination Act of 1999.

Spatial variability of produced-water quality and alternative-source water analysis applied to the Permian Basin, USA

Interest in both environmental impact and potential beneficial uses of produced water (PW) has increased with growth in unconventional oil and gas production, especially in semi-arid regions, e.g. the Permian Basin, the most productive tight-oil region in the USA. Characterization of PW compositional variability is needed to evaluate environmental impact, treatment, and reuse potential. Geochemical variability of PW from Guadalupian (Middle Permian) to Ordovician formations was statistically and geostatistically evaluated in the western half of the Permian Basin (Delaware Basin, Central Basin Platform, and Northwest Shelf) using the US Geological Survey’s Produced Waters Geochemical Database and the New Mexico Water and Infrastructure Data System. Mean total dissolved solids (TDS) of PW increased with depth in the Delaware Basin and Central Basin Platform to the Delaware and Wolfcamp formations (Guadalupian age). Mean TDS decreased with further increases in depth. In contrast, the mean salinity of PW was significantly higher within the shallow, younger formations (largest mean TDS in the Artesia Formation); TDS decreased with depth below Guadalupian age formations in the Northwest Shelf. Kriged contour maps of TDS and major ions illustrated spatial variability across the three geo-structural regions as a function of depth. The occurrence of meteoric waters in upper and deeper formations across the three regions was significant, and was attributed to Laramide Orogeny and Basin and Range extension uplifting and tilting effects and recent water flooding. These results quantify PW composition variability, and suggest that upon treatment, PW would support some uses such as onsite reuse and mining.

Physicochemical Analysis of Mymensingh Municipality Sewage Water and Old Brahmaputra River water

The study was conducted to investigate the physicochemical properties of the Old Brahmaputra River and Sewage water in Mymensingh Municipality. To perform the study fifty samples were collected from five different stations from the river and surrounding sewage discharge points. The samples were analyzed to determine pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), Lead (Pb) and Cadmium (Cd). The mean value of pH was 7.1 and 6.8 for river and sewage water samples, respectively. Mean EC value was 183 μS/cm and 589.18 μS/cm for river and sewage samples, respectively signifies that EC of all samples were within the acceptable range. 66.32 ppm and 260.36 ppm were the mean TDS value for river and sewage samples, respectively indicates no harm to aquatic lives and irrigation water use. Mean DO and BOD values for river water samples were 4.21 mg/L and 6.02 mg/L, respectively. 3.08 mg/L and 9.98 mg/L were the mean DO and BOD values for sewage water samples, respectively implies that river water is usable for irrigation but sewage water is unfit for it. Mean Pb concentration for river and sewage water samples was 0.428 ppm and 0.467 ppm, respectively.J. Environ. Sci. &amp; Natural Resources, 10(2): 105-108 2017

Physico-Chemical Quality of Selected Drinking Water Sources in Mbarara Municipality, Uganda

The study assessed the physico-chemical quality of selected drinking water sources (springs, boreholes, shallow wells and rainfall) in Mbarara municipality with respect to World Health Organization (WHO) drinking water guidelines and other guidelines in light of the increased anthropogenic activities in the municipality. A total of 70 water samples were collected from purposively selected boreholes, springs, wells and rainwater in Nyamitanga, Kamukuzi and Kakoba divisions of Mbarara municipality with various human activities. The samples were analysed for physico-chemical parameters: Temperature, pH, Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), Total Dissolved Solids (TDS), Electrical Conductivity (EC) and Total hardness using American Public Health Association (APHA) standard methods. The mean temperature and pH ranged between 18.07 °C - 23.45 °C and 5.74 - 7.54, respectively. The mean DO values were found to be between 4.84 and 12.86 mg/l; whereas mean BOD was within the range of 1.83 - 7.71 mg/l. The mean TDS and EC of the water samples ranged, between 33.40 - 569.20 mg/l and 29.30 - 1139.90 μS/cm respectively. Furthermore, the lowest and highest mean total hardness were 70.00 and 264.00 mg/l, respectively. The recorded mean water temperatures for each of the water sources were above the WHO threshold temperature (15 °C) which makes drinking water palatable. Boreholes in Nyamitanga and Shuhaddea Secondary Schools, spring in Kiswahili, well in Kisenyi and rainwater in Mbarara University of Science and Technology (MUST) had mean pH below the WHO minimum guideline value (6.5) hence acidic. Borehole in Nyamitanga secondary school, spring in Kisenyi, shallow well in Nyamitanga and the rainwater in MUST had mean DO values below the WHO range (10 - 12 mg/l). Borehole in Shuhaddea Secondary School and the well in Kisenyi had average BOD values above the range of European Union guideline values (3 - 6 mg/l). TDS and EC of all the water sources were below the WHO maximum guideline limits of 1000 mg/l and 1500 μs/cm respectively. Total hardness was also below the WHO harmless limit of 1000 mg/l. However rainwater in MUST was moderately soft while the other drinking water sources exhibited moderate to full total hardness. The physicochemical parameters of some of the selected water sources in Mbarara municipality have been compromised mainly by the increased human activities especially croplands, latrines, landfills, transportation, animal and municipal wastes at the vicinity of the water sources. Mbarara municipal council should therefore ensure proper sanitation and water safety plans for these drinking water sources to avoid further contamination from the human activities.

Identification of hydrogeochemical processes in groundwater of Dawa River basin, southern Ethiopia.

Dawa River basin in southern Ethiopia is covered by volcanic, basement, and sedimentary rocks. Locating good quality groundwater is a challenge in most parts of the basin. Statistical analysis and graphical plots of 94 hydrochemical data of groundwater were used as a main tool to acquire an insight into the major processes that control groundwater chemistry. In the volcanic terrain groundwater is dilute (mean total dissolved solids (TDS): 152mg/l), while salinity is the highest in the sedimentary terrain (mean TDS: 1750mg/l). NO3 (-) varies from below the detection limit to 433mg/l NO3 (-). In 26% of the water samples, nitrate concentration is above the human-affected value, 5mg/l NO3 (-). In 6% of the samples, NO3 (-) concentration is above the limit recommended in drinking water, 50mg/l NO3 (-), by WHO. Concentration range of the other major ions is also high and hydrochemical water types are diverse, suggesting the effect of various hydrogeochemical processes on the water chemistry. Chemical data analysis revealed that in the volcanic and most parts of the basement terrains silicate hydrolysis is the dominant process. Gypsum dissolution is the main process in the sedimentary terrain. Dissolution of gypsum is also important at few locations along dry riverbeds in the semiarid area where the effect of evaporation on the water chemistry is considerable. Loading of factors with K(+) and SO4 (2-), K(+)and NO3 (-), and NO3 (-) and correlation of SO4 (2-) with Cl(-), along with the observed high nitrate concentration, indicate the effect of surface contamination sources on the water quality.

Chemical denudation in the Yellow River and its geomorphological implications

Chemical denudation plays an important role in regulating atmospheric CO2 balance and modulating global climate. With weekly collected water samples at three stations on the Yellow River mainstem from July 2011 to July 2012, we investigate its chemical denudation characteristics on the basis of water geochemistry and discuss the geomorphological implications. Because of limited atmospheric inputs into the Yellow River, chemical weathering is of first importance in affecting the chemical compositions of its water geochemistry. As a result of extensive carbonates within the watershed, carbonate dissolution is the major source of the dissolved solids, accounting for 28–33.7% of the total dissolved solids (TDS). In contrast, silicate weathering contributes only 9.9–10.9%. With a mean TDS concentration of 639mgl−1, the TDS flux into the ocean is estimated at 16Mtyr−1, corresponding to a specific chemical denudation rate of 21.3tkm−2yr−1. Comparative analysis with physical erosion suggests the dominance of physical erosion over chemical weathering in providing riverine loads. Rapid removal by physical erosion may have restrained the chemical denudation processes. Rock weathering consumes, on average, 2.3Mt of atmospheric CO2 during the one-year-long sampling campaign, accounting for 0.22–0.31% of the global annual CO2 consumption through chemical weathering. Of the CO2 consumed, 74% is caused by carbonate weathering and 26% by silicate weathering, indicating the predominance of carbonate weathering in consuming atmospheric CO2 within the watershed.

Assessment of drinking water quality and its potential health impacts in academic institutions of Abbottabad (Pakistan)

The continuously deteriorating water quality situation in Pakistan is posing serious health threats to the population. The study aimed to assess the physicochemical and bacteriological quality of drinking water in different institutions of Abbottabad city and its potential health effects on staff and students. About 63 samples from 60 institutions across different locations of Abbottabad city were analysed for physicochemical (temperature, pH, total dissolved solids (TDS) and electrical conductivity (EC)) and bacteriological (total coliforms and Escherichia coli) analysis using standard methods. Water quality (n = 60) and health related (n = 300) information was obtained through pre-designed survey questionnaires. Results showed that all water samples were aesthetically acceptable. In physicochemical analysis, the mean temperature and pH values were found at 27.12 ± 2.47°C and 7.98 ± 0.24, respectively. The mean TDS and EC values were found at 335.42±86.3 ppm and 647.38±174.82 μS, respectively. Bacteriological analysis showed that THBC in water samples ranged from 10 to 58000 CFU/ml with 63.5% samples exceeding the WHO drinking water quality limits. Results of total coliform analysis showed most-probable-number values ranged between 0 and > 2400 per 100 ml with 42 samples (66.6%) exceeding permissible limits. After isolation, identification of strains was performed by API 20E Identification System. Three pathogenic species namely Citrobacter sakazakii, Enterobacter cloacae and Salmonella choleraesius were identified. Data obtained through questionnaires identified three major sources of drinking water i.e. government supply, bore well and tube well. Most of the secondary level institutions used government supply (54%), higher secondary institutions used bore well (53%) and post secondary institutions used tube wells (44%) to meet their drinking water needs. Bore well was found to be the most widely used source. Majority of institutions i.e. 75% secondary, 47% higher secondary and 39% post secondary consumed water without any prior treatment. Respondents reported diseases in the order of typhoid > diarrhoea > dysentery > hepatitis > abdominal pains > skin infections. Disease prevalence in secondary institutions was found higher as compared to the higher and secondary institutions. Presence of total coliforms in 66.6% of water samples clearly indicates the need of monitoring at regular intervals, effective treatment processes and sound policy recommendations in Abbottabad city.

Evaluation of physicochemical and antioxidant properties of sourwood and other Malaysian honeys: a comparison with manuka honey

BackgroundThe aim of the present study was to evaluate the physical, biochemical and antioxidant properties of four Malaysian monofloral types of honey (gelam, longan, rubber tree and sourwood honeys) compared to manuka honey.Several physical parameters of honey, such as pH, moisture content, electrical conductivity (EC), total dissolved solids (TDS), color intensity, total sugar and sucrose content, were measured. A number of biochemical and antioxidant tests were performed to determine the antioxidant properties of the honey samples. Hydroxymethylfurfural (HMF) levels were determined using high performance liquid chromatography.ResultsThe mean pH, moisture content, EC and TDS of Malaysian honey were 3.90 ± 0.12, 17.01 ± 3.07%, 0.59 ± 0.17 mS/cm and 294.87 ± 81.96 ppm, respectively. The mean color and HMF level was 102.07 ± 41.77 mm Pfund and 49.51 ± 0.12 mg/kg, respectively. Sourwood honey contained the highest contents of phenolics (580.03 ± 0.38 mggalic acid/kg) and flavonoids (156.82 ± 0.47 mgcatechin/kg) with high DPPH radical scavenging activity (59.26 ± 3.77%) as well as ferric reducing power [648.25 ± 0.90 μM Fe (II)/100 g]. Sourwood honey also exhibited the highest color intensity. Several strong positive correlations were observed amongst the different antioxidant parameters and the various antioxidant tests.ConclusionThis is the first time that the antioxidant potential of both sourwood and rubber tree honeys have been reported. Our results indicated that Malaysian honey (specifically sourwood honey and longan honey) is a good source of antioxidants compared to Manuka honey.

Physicochemical and Antioxidant Properties of Algerian Honey

The aim of the present study was to characterize the physical, biochemical and antioxidant properties of Algerian honey samples (n = 4). Physical parameters, such as pH, moisture content, electrical conductivity (EC), total dissolved solids (TDS), color intensity, total sugar and sucrose content were measured. Several biochemical and antioxidant tests were performed to determine the antioxidant properties of the honey samples. The mean pH was 3.84 ± 0.01, and moisture the content was 13.21 ± 0.16%. The mean EC was 0.636 ± 0.001, and the mean TDS was 316.92 ± 0.92. The mean color was 120.58 ± 0.64 mm Pfund, and the mean 5-hydroxymethylfurfural (HMF) content was 21.49 mg/kg. The mean total sugar and reducing sugar contents were 67.03 ± 0.68 g/mL and 64.72 ± 0.52 g/g, respectively. The mean sucrose content was 2.29 ± 0.65%. High mean values of phenolic (459.83 ± 1.92 mg gallic acid/kg), flavonoid (54.23 ± 0.62 mg catechin/kg), ascorbic acid (159.70 ± 0.78 mg/kg), AEAC (278.15 ± 4.34 mg/kg), protein (3381.83 ± 6.19 mg/kg) and proline (2131.47 ± 0.90) contents, as well as DPPH (39.57% ± 4.18) and FRAP activities [337.77 ± 1.01 µM Fe (II)/100 g], were also detected, indicating that Algerian honey has a high antioxidant potential. Strong positive correlations were found between flavonoid, proline and ascorbic acid contents and color intensity with DPPH and FRAP values. Thus, the present study revealed that Algerian honey is a good source of antioxidants.