Fluctuations in potable water quality in Cyprus during the past two decades – the role of seawater desalination

To investigate the changes in heavy metal content in the sub glacial water during the freezing and thawing process of seasonally frozen lakes, the Wuliangsuhai Lake in northern China was taken as the research object. The ice thickness, water depth, and heavy metal content at different depths of the lake were measured during the freezing and thawing periods. Based on a large amount of measured lake heavy metal data, MATLAB 2022b software is used to model data fitting and optimization identification, and wavelet analysis and 24 h sliding average method are used for verification analysis to describe the variation process of heavy metal concentration in ice water with depth and time. The results show that during the freezing and thawing periods of lakes, the water level is constantly changing, but the heavy metal content in the water below the ice follows the same distribution with water depth. During the freezing process, the heavy metal content in the water increases with the increase in ice thickness. A new numerical model describing the spatiotemporal distribution of heavy metals under the ice during the freezing period of the lake was obtained through calculation. The overall trend of the simulated contour lines is consistent with the measured values and has a small error. This study provides a reference for predicting the changes in heavy metal content under the ice cover during the freezing period in cold and arid regions. The model can be used to simulate the content values of heavy metals at different depths and times.

The present paper aims at evaluating the vailability quality and future horizons of potable water in the city of Shatra as a model. This is done in accordance with certain subjective and objective factors alongside the classification map of Shatra as a residential area. This system follows geographical studies specialized in urban construction. The problem of the present paper as well as the data approaching that problem have been chosen from the records of 2018. The researcher offered (919) questionnaire forms to be answered by a sample of dwellers in that area. Besides, the researcher also followed lab analysis of water samples collected from districts in the city of Shatra. GIS technology was also used to arrive at the real water share people are supposed to receive and the quality of potable water they actually have. It has been found that there is a clear scarcity in potable water where an individual is supposed to get 250 liters a day and that has not yet been achieved. Water Purification facilities are small in number and cannot meet people’s need for potable water. This is because the production energy for those facilities is supposed to be from 175-to-1000 cubic meters per hour. However their best production did not exceed the 140-800 cubic meter per hour. The gross need for potable water was estimated to be 8908500 cubic meter per hour. Water shortage is thus of about 585 cubic meter per hour. The future shortage is calculated to reach 46800000 cubic meter per hour in 2028. Above all, water was not good for use by dwellers as it does not meet world standards of healthy potable water.

Heavy metal concentrations in surface waters of Hurghada and environs, Red Sea Coast, Egypt, and their correlation with sediment distribution

Purpose. Assessment of the dynamics of heavy metal accumulation in water, bottom sediments, and fish of water bodies of different purposes in Dnipropetrovsk region. Methodology. The study on heavy metal contents in water, bottom sediments, and hydrobionts (fish) was conducted at various water bodies (Dnipro-Donbas hydraulic canal), fish ponds (ponds of PrJSC “AgroSoyuz”, PrJSC “Petrykivsky Rybhosp” and PE «Agrofirma «Nakhodka»), and multipurpose reservoirs (Dnipro reservoir, Sholokhivske reservoir) in Dnipropetrovsk region from 2015 to 2024. The determination of heavy metal concentrations (Pb, Cd, Mn, Cu, Fe, Ni, Zn) was carried out at the laboratory of the Research Center for Biosafety and Environmental Monitoring of Agricultural Resources of Dnipro State Agricultural and Economic University. The metal content was analyzed using atomic absorption spectrophotometry. The heavy metal contents were measured in four fish species (European perch, roach, Prussian carp, common carp). Sampling, data processing, and statistical analysis were conducted according to standard hydrochemical, hydrobiological, and ichthyological methods. The heavy metal contents were determined in fish muscles. Water quality was assessed according to general requirements and standards for fishery water bodies. Findings. The heavy metal contents in ecosystems of water bodies of different purposes was determined. In the sediment of ponds of PrJSC “AgroSoyuz” and PrJSC “Petrykivsky Rybhosp”, the heavy metal contents were significantly higher than in water or fish body: manganese within 41.24–68.43 mg/kg, cadmium – 0.32 mg/kg, lead 1.50–4.90 mg/kg (for ponds of PrJSC “AgroSoyuz”); manganese – 29.73 mg/kg, cadmium – 0.54 mg/kg, lead 5.72 mg/kg (for recreational pond of PrJSC “Petrykivsky Rybhosp”). For the water of these ponds, which is used for aquaculture, an excess of the content of some heavy metals – Mn, Zn, Cd - was recorded, and for the pond of PrJSC “AgroSoyuz” also Cu. Exceeding the normative heavy metal content for pond water of PE “Agrofirma “Nakhodka” was not noted. The content of some heavy metals in the water of the upper part of the Dnipro reservoir (Cu, Fe) did not meet the fishery norms. At the same time, the heavy metal contents in water and fish of these water bodies does not exceed the fishery standards for water used for fishery purposes. The heavy metal contents in the water of the upper part of the Dniprovske Reservoir (except for the Samara Bay) corresponded to fishery standards. The water in the Dnipro-Donbas hydrotechnical canal was characterized by high levels of heavy metals. Of the 6 investigated heavy metals, the maximum allowable concentrations were not exceeded only for lead (0.40 mg/dm3) The heavy metal contents in C. carpio muscles (juveniles and table fish) in different ponds of PrJSC “Petrykivskyi Rybhosp” (nursery and fattening) corresponded to fishery standards during the three years of the study (2011, 2015, 2016). In the Sholokhivske reservoir, the zinc content in C. gibelio muscles was 46.50 mg/kg, slightly exceeding the maximum allowable concentrations. Exceedances of copper and lead content were not noted. For fish from the Dnipro reservoir, the content of most heavy metals was elevated. In the meat of pelagic roach (R. rutilus), only copper content was within the normal limits (1.56 mg/kg), while all other 6 heavy metals exceeded the maximum allowable concentrations. In the meat of benthophagous Prussian carp (C. gibelio), elevated levels of accumulation of heavy metals were observed for manganese, iron, lead, and nickel, while zinc, copper, and cadmium content were within the standards. In the meat of European perch (P. fluviatilis), the highest content of heavy metals was observed for iron (80.54 mg/kg), with elevated levels observed for manganese, zinc, lead, and nickel. The obtained results indicate that the hydroecosystem of the Dniprovske reservoir, unlike other water bodies in the region, is significantly polluted with heavy metals. This is adequately reflected in the levels of heavy metal accumulation in the organisms of fish from different ecological groups - pelagic herbivores, benthophagous bottom-feeders, and predators. Originality. For the first time, the content of heavy metal accumulation in water, bottom sediments, and fish of water bodies of different purposes in Dnipropetrovsk region has been carried out over several years (2015–2024). Practical Value. The obtained results have theoretical and practical importance for the preparation of scientific-biological justifications for the fishery use of water bodies of various purposes in the region. Continuous monitoring of the heavy metal contents in hydrobionts is necessary to ensure food safety and the quality of raw materials and food fish products. Keywords: Dnipropetrovsk region, heavy metals, Dnipro Reservoir, Dnipro-Donbas Canal, ponds, Sholokhivske Reservoir, water, sediment, fish, accumulation of pollutants.

Lake Burullus is an important source of fish production in Egypt; it produces 20.5% of the Egyptian fisheries' production. There is intense controversy about the heavy metal pollution in Burullus water and its effects on fish health and safety for human consumption. Heavy metals represent a major concern for aquatic life and could negatively affect fish health. Agricultural and industrial water drainage represents a considerable part of the lake water supply. The present work was conducted to determine heavy metal concentrations in lake water and blue tilapia Oreochromis aureus musculature. Water samples were collected from six locations to determine cadmium, copper, lead, zinc and iron. Sixty O. aureus fish samples were also collected from the same sampling points to assess the prevalent parasites infesting fish and to determine the heavy metal (Cd, Cu, Pb, Zn and Fe) concentrations in fish musculature then study the relationship between heavy metals concentration and prevailing fish parasites. Results indicated that 53.34% of the examined fish were infested with encysted metacercaria. Centrocestus formosanus, Prohemistomum vivax, and Euclinostomum heterostomum were retrieved from gills, musculature, hepatopancreas and the posterior kidney. The parasitic intensity in fish tissues was between 1 and 9 cystg-1. Centrocestus formosanus was identified using the polymerase chain reaction in the gill tissues of 16 fish. The gill parasitic copepod Lamproglena monodi was identified in one fish. Degenerative changes such as thickening, corrugation, and destruction of gill filament are the most dominant pathological changes in infested fish gills. Heavy metal concentrations in water samples were at normal levels, except for copper and iron in the southern part of the lake. All heavy metals in fish musculature were below the permissible limits. The parasitic infestation was more dominant in the northern part of the lake than in the southern region; this could be due to elevated copper concentration in the southern part of the lake that could negatively affect the survival of the first intermediate host and parasite cercaria. In conclusion, captured fish from Lake Burullus were safe for human consumption, and heavy metal pollution in lake water does not represent a severe risk.

Vital Signs: Deficiencies in Environmental Control Identified in Outbreaks of Legionnaires’ Disease—North America, 2000–2014

<div class="htmlview paragraph">Potable water is undoubtedly one of the most critical resources for the International Space Station (ISS) crews. The amount and quality of this resource, mainly provided to the ISS by the Space Shuttle and Progress, and in the near future by logistic vehicles Automated Transport Vehicle (ATV) and HTV, must be compatible with the crew consumption needs and health-related requirements.</div> <div class="htmlview paragraph">For this purpose, potable water must satisfy very stringent quality requirements from chemical and bacteriological point of view. The definition of such requirements, resulting from medical studies, lessons learned, technical constraints, is reached in agreement among ISS International Partners.</div> <div class="htmlview paragraph">Two different quality standards are defined, one for the ISS Russian Segment, the other for the US Segment and other International Partners.</div> <div class="htmlview paragraph">The ATV, a program under European Space Agency (ESA) contract and EADS Space Transportation (EST) prime contractor-ship, is the only logistic vehicle requested to transport and deliver potable water to ISS according to both quality standards.</div> <div class="htmlview paragraph">Significant efforts have been spent in Alenia Spazio, responsible for the ATV Integrated Cargo Carrier, to define all the activities necessary to accomplish this task. The main aspects under consideration have been: selection of materials in contact with water, identification of suitable potable water sources, water preparation and disinfection, and pre-conditioning of equipment. This paper focuses on preparation and quality of potable water as obtained in dedicated ground facilities.</div> <div class="htmlview paragraph">The quality and stability of source water are an essential pre-requisite to attain the required standards. Disinfection techniques using colloidal silver and iodine are discussed, and their implementation in the ATV Water Preparation Facility at Società Metropolitana Acque Torino (SMAT) premises is presented. The results of chemical and micro-biological analyses performed on potable water batches treated with the defined techniques show that the requirements are fully satisfied.</div>

The coastal waters of Palu Bay are vulnerable to pollution from various activities of the surrounding population. This study aimed to determine the content of heavy metals Pb, Cd, and Cu in the water and sediment of the coastal waters of Palu Bay. The analysis of heavy metal content (Pb, Cd, and Cu) in water and sediment was conducted using an Atomic Absorption Spectrophotometer (AAS). Based on the research, the results showed that the heavy metal content in the water ranged from undetected to 0.04 mg/L for Pb, undetected for Cd and Cu. The heavy metals content in the sediment ranged from 2.17 to 13.8 mg/kg for Pb, undetected to 0.17 mg/kg for Cd, and 5.02 to 37.67 mg/kg for Cu. The Pb content in the water has significantly exceeded the quality standard as stipulated in the Minister of Environment Decree No. 51 of 2004. The Pb content in the sediment is still within safe limits according to Canadian quality standards. The Cd content in the sediment exceeded the quality standard at station 6, while for the other 9 stations, it was not detected. The Cu content in the sediment at 5 stations (2, 3, 4, 5, and 10) has exceeded the Canadian quality standard of 18.7 mg/kg.

Heavy metals are potentially toxic to organisms causing lethal and sub lethal effects. Above threshold levels, these metals have been shown to adversely affect both aquatic and terrestrial organisms. Human health may also be impacted negatively through consumption of metal-contaminated foods and water. Lake Naivasha, Kenya, like many freshwater bodies in developing countries is a source of fish and water for human consumption in Naivasha town and its environs. Ironically, the lake receives untreated floricultural, agricultural and industrial effluents from its catchment area. In the recent past, there have been unconfirmed reports that fish from this lake are contaminated with heavy metals mainly Cu, Hg, Cd and Pb to levels that are harmful to humans. It is against this background that this study was conducted to determine the sources of the aforementioned heavy metals in the lake, their concentrations in water and sediments and in common carp (<em>Cyprinus carpio</em>) that constitutes a major portion of the Lake Naivasha fishery. Water, sediment and fish samples were collected from purposefully selected sites in six sampling occasions during both the dry and wet seasons. Analyses for heavy metals in fish, sediment and water samples were done using an Atomic Absorption Spectrophotometer (AAS). The study findings indicate that the heavy metal concentrations in the water and sediments collected from impacted sites were significantly higher (p<0.05) compared to those from unexpected sites. In spite of this, the metal concentrations in water were significantly lower than those recommended by the WHO and USEPA as drinking water guideline values. Metal concentrations in <em>C. carpio</em> were also significantly lower (p<0.05) than the World Health Organization (WHO) recommended levels for fish intended for human consumption. Based on these findings, it is safe to conclude that drinking water and fish collected from Lake Naivasha do not pose immediate health risks to human health. Despite this observation, we recommend continuous monitoring of heavy metal concentrations in water and sediment in the lake given their potential for bioaccumulation and biomagnifications and likely adverse effects on aquatic organisms and humans.

안동호와 임하호의 수환경내 중금속의 오염정도와 서식 어종간의 중금속 축적 정도를 알아보기 위해 양호수의 수질, 저니 및 서식어종인 붕어를 이용하여 중금속 함량을 비교 분석하였다. 안동호와 임하호 수질과 저니내 중금속 함량은 안동호에서 높은 함량을 보이며, As는 함량의 차이가 큰 것으로 나타났다. 안동호와 임하호에 서식하는 붕어의 중금속 함량의 경우 안동호에 서식하는 붕어에서 높은 함량을 보이며, Cr, Cu, Cd 및 As는 함량의 차이가 큰 것으로 나타났다. 또한 비늘, 근육, 뼈 조직은 안동호와 임하호의 함량차이가 크며, 안동호에서 높은 함량을 나타냈다. 본 연구의 결과 안동호와 임하호의 수질과 저니 및 서식어종인 붕어의 중금속 함량은 안동호에서 임하호보다 중금속 함량이 높게 나타났으며, 안동호와 임하호의 함량차이도 큰 것으로 나타났다. 이는 안동호의 경우 안동호 상류 지점의 폐광산과 농경지로부터 하상퇴적물이 유입되어 하상퇴적물 속에 포함된 유기물을 붕어가 먹이로 섭취함으로써 중금속 함량에 영향을 미친 것으로 생각된다. Heavy metal contamination levels in Andong reservoir and Imha reservoir were measured with heavy metal contents in both water and sediment, and analyzed with heavy metal accumulation level in inhabitant fish, Carassius auratus, using an inductively coupled plasma spectrometer and an atomic absorption spectrometer. High levels of heavy metal contents in water, sediment and the tissues of C. auratus were detected. Likewise, relatively high levels of As were detected in water and sediment from Andong reservoir. In addition, higher levels of Cr, Cu, Cd and As content were detected in muscle and bone tissues of fish from Andong reservoir than those from Imha reservoir. As a result, the heavy metal content of water, sediment and inhabitant fish, C. auratus, in Andong reservoir was higher than Imha reservoir. We proposed that heavy metal contamination in water and inhabitant fish is attributed to various metals derived from abandoned mines and farmlands that are upstream of Andong reservoir.

This study demonstrates the impact of wastewater of El-Sail Drain on the health of Oreochromis niloticus collected from two sites of River Nile at Aswan Governorate. One of these sites is before (I) and the other is after (II) the disposal point of El-Sail drain. The physicochemical parameters of water (pH, electric conductivity, total dissolved solids, dissolved oxygen, biological and chemical oxygen demands, nitrite, nitrate and ammonia) were determined. Heavy metals (Cu, Pb, Cd and Ni) concentrations in water and fish tissues (gills, muscles, liver and gonads) were detected. The microbiological, parasitological and pathological conditions of fish were also investigated. Higher values of pH, EC, BOD and COD were detected in site II than from site I. In contrast to DO, nitrite, nitrate and ammonia which were lower in site II. Heavy metals concentrations in water of both sites, especially Ni, Pb and Cd exceeded the permissible limits and its abundance followed the order: Pb>Ni>Cd>Cu. Total bacterial count, total coliform, Salmonella sp., Shigella sp. and E. coli were detected in higher numbers in water samples from site II. Moreover, the fish caught from that site revealed higher bacterial and parasitic infection. The bioaccumulation of Ni and Pb exceeded the maximum permissible limit; however, Cu and Cd concentrations were below the permissible limit in different tissues. The bioaccumulation factor of Cu showed its highest value in liver. The histopathological lesions were more prominent in fish collected from site II. So, consuming fish caught from the studied sites around El-sail drain disposal point represents serious hazard on human health.

This study aimed to investigate nine heavy metal concentrations (As, Cd, Cr, Pb, Cu, Fe, Zn, Mn and Ni) in water, sediment and snakehead fish (Channa striata) and to identify abnormal chromosomes in C. striata from a reservoir near an industrial factory and a reference area. Heavy metal concentrations were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). The metal concentrations in the water, sediment and C. striata samples did not exceed the standard limit of Thailand, except for Cr concentrations, which exceeded water quality standards. The concentrations of Cd, Fe, Mn and Ni in C. striata samples between the reservoir and the reference area were significantly different (p < 0.05). The diploid chromosome number of C. striata from both areas was (2n = 42). Eight types of abnormal chromosomes were identified and classified as a single-chromatid gap, a single-chromatid break, centric fragmentation, a centric gap (CG), fragmentation, deletion, single-chromatid decomposition and iso-arm fragmentation. The most frequent abnormal chromosome in the samples was CG. The percentages of abnormal chromosomes in the C. striata samples from the reservoir near the industrial factory and the reference area were significantly different (p < 0.05) at 8.44 and 1.20, respectively.

The new technologies used in the green transition towards carbon-free societies typically demand extensive use of metals. This leads to a heavily growing need for exploration and extraction of ore deposits. Exploration can be facilitated by measuring metal concentrations in ground and surface waters carrying trace concentrations of metals leached from nearby deposits. Currently, measuring metal concentrations in water is slow and expensive and it cannot be done on-site, which hinders the discovery of new ore deposits. To address this challenge, we have developed a method to collect and concentrate the dissolved metals in a solid filter and measure the metal concentrations directly from the filter with a portable X-ray fluorescence spectrometer. The permeable filter is made of mesoporous silicon modified with bisphosphonates. Two types of adsorbing materials for the filters were prepared based on scalable production methods: i) regenerative etching of metallurgical grade silicon powder, and ii) magnesiothermic reduction of silica from barley husks. Empirical calibrations were prepared in a concentration range of 10–200 μg/L for Mn, Co, Ni, Cu, Zn, and Pb using water samples prepared by spiking well water with standard metal solutions. Both filter types were tested for their ability to adsorb metals from the real water samples taken from drill holes. The developed system was able to detect metal concentrations down to 12 μg/L (ppb) showing its potential for on-site measurements of dissolved metals in water samples, which could be feasible in the discovery of new mineral deposits. This innovation enables smart sampling during exploration and provides real-time information on metal concentrations in water.

Scientific aspects of supplying the population with transported water

Total concentrations and sources of heavy metal pollution in global river and lake water bodies from 1972 to 2017