Water In Lebanon Research Articles

Multidrug-resistant pathogens contaminate river water used in irrigation in disenfranchised communities

The contamination of fresh surface waters poses a significant burden on human health and prosperity, especially in marginalized communities with limited resources and inadequate infrastructure. Here, we performed in-depth genomic analyses of multidrug-resistant bacteria (MDR-B) isolated from Al-Oueik river water that is used for irrigation of agricultural fields in a disenfranchised area that also hosts a makeshift Syrian refugee camp. A composite freshwater sample was filtered. Faecal coliforms were counted and extended spectrum cephalosporins and/or ertapenem resistant bacteria were screened. Isolates were identified using MALDI-TOF-MS and analysed using whole-genome sequencing (WGS) to identify the resistome, sequence types, plasmid types, and virulence genes. Approximately 106 CFU/100 mL of faecal coliforms were detected in the water. Four drug-resistant Gram-negative bacteria were identified, namely Escherichia coli, Klebsiella pneumoniae, Enterobacter hormaechei, and Pseudomonas otitidis. Notably, the E. coli isolate harboured blaNDM-5 and a YRIN-inserted PBP3, representing an emerging public health challenge. The K. pneumoniae isolate carried blaSHV-187 as well as mutations in the gene encoding the OmpK37 porin. Enterobacter hormaechei and P. otitidis harboured blaACT-16 and blaPOM-1, respectively. This report provides comprehensive genomic analyses of MDR-B in irrigation water in Lebanon. Our results further support that irrigation water contaminated with faecal material can be a reservoir of important MDR-B, which can spread to adjacent agricultural fields and other water bodies, posing both public health and food safety issues. Therefore, there is an urgent need to implement effective water quality monitoring and management programs to control the proliferation of antibiotic-resistant pathogens in irrigation water in Lebanon.

Chemical composition of fogwater collected at four sites in North- and Mount-Lebanon during 2021

A field campaign is established at four sites in North-Lebanon (Akkar district) and Mount-Lebanon (Keserwan district) for the first time between February and June 2021 using the Caltech Active Strand Cloud Collector (CASCC). Overall, 14 fog events are sampled, of which 5 samples from Fnaideq, 5 samples from Beit Younes, 1 sample from Qamouaa, and 4 samples from Bzomar. Their mean liquid water content (LWC) varies between 0.023 and 0.045 g m−3, their mean conductivity (K) varies between 53.3 and 2210 μS cm−1, and their pH varies between 6.5 and 7.8. The dissolved organic carbon (DOC) varies between 7.4 and 82.6 ppm. DOC shows a good correlation with magnesium and chloride, and no relationship with the liquid water content (LWC). The total average ionic concentrations (TIC) in Fnaideq, Qamouaa, Beit Younes, and Bzomar are respectively 3106.9, 4112.2, 4972.4, and 5969.1 μEq L−1. TIC shows a negative correlation with LWC (r2 = 0.7), suggesting that an increase in the LWC with dilute the solute concentration. The fog water in Lebanon is characterized by high concentrations of Ca2+ (35% of the measured TIC), Na+ (20%), Cl− (12%), NH4+ (11%), and Mg2+ (11%). The contribution of the acidic ions (SO42− and NO3−) from industrial and vehicular sources is minimum (respectively of 3% and 1%). NH4+, originating from the scavenging of gaseous ammonia and particulate ammonium nitrate and sulfate and from agricultural activities, and Ca2+‏, originating from the scavenging of coarse particles, act as acid neutralizers and are the main cause for the relatively basic pH of fogs in Lebanon. The contribution of Ca2+ and Mg2+ to sea-salt is found to be negligible, whereas the contribution of SO42− to sea salt is higher. Zn and Ni are the most two abundant heavy metals at all sampling sites. Their concentrations vary respectively between 137.6 and 349.7 μg L−1 (mean of 211.8 μg L−1) and between 38.2 and 585.5 μg L−1 (mean of 197.6 μg L−1). They account together for an average of 58% of the total elemental concentration. The high enrichment factors (higher than 100) for Ni, Cu, Zn, Hg, and Cd suggest significant anthropogenic contamination at the sampling sites. The ionic sources are also determined by the Principal Component Analysis (PCA). Two principal components (PCs) that account together for 62% of the total variance are identified by PCA. High ionic loadings are observed indicating a well-mixed mixture of local anthropogenic sources (factories, motor vehicle emissions, sea transportation, agriculture, combustion, civil construction, etc.) and some natural sources (sea and crust/soil).

Solar-Powered Solutions for the Water and Energy Shortage Problem: The Case Study of Nahr El Bared, Lebanon

Solar power is an effective way to reduce the dependency on conventional fuels and mitigate the water and energy shortage issue. The main aim of the current paper is to assess and compare the techno-economic feasibility of rooftop grid-connected photovoltaic energy systems for generating electricity and generating drinkable water in Nahr El Bared, Lebanon. To this aim, the present paper first reviews previous scientific studies associated with the water resources and energy situation to summarize the current status in Lebanon. According to this review, Lebanon's water resources are highly polluted, domestic and industrial sewage is largely untreated, and intolerable agricultural practices further exacerbate the situation. Furthermore, population and economic growth and the continuous utilization of old power plants have led to an increase in the number of hours of power outages in the country. Accordingly, the proposed project aims to evaluate the viability of using solar energy as an alternative solution to the shortage of water and energy in the country. Secondly, the techno-economic performance of the proposed system in the selected region was evaluated based on the variations in financial parameters using RETScreen Experts software. The results demonstrate that 11770–13451kWh/yr could be generated from the solar system, which can help reduce the energy shortage and generate drinkable water. Furthermore, the investment was found to be economically viable and attractive for investors. This paper concludes that solar energy can be able to solve the energy shortage of electricity, reduce the country's electricity costs, and produce freshwater for drinking and domestic use in the country.

The dissemination of antimicrobial resistance determinants in surface water sources in Lebanon.

The prevalence of antibiotic-resistant bacteria in surface water in Lebanon is a growing concern and understanding the mechanisms of the spread of resistance determinants is essential. We aimed at studying the occurrence of resistant bacteria and determinants in surface water sources in Lebanon and understanding their mobilization and transmission. Water samples were collected from five major rivers in Lebanon. A total of 91 isolates were recovered by incubating at 37°C on Blood and MacConkey agar out of which 25 were multi-drug resistant (MDR) and accordingly were further characterized. Escherichia coli and Klebsiella pneumoniae were the most common identified MDR isolates. Conjugation assays coupled with in silico plasmid analysis were performed and validated using PCR-based replicon typing (PBRT) to identify and confirm incompatibility groups and the localization of β-lactamase encoding genes. Escherichia coli EC23 carried a blaNDM-5 gene on a conjugative, multireplicon plasmid, while blaCTX-M-15 and blaTEM-1B were detected in the majority of the MDR isolates. Different sequence types (STs)were identified including the highly virulent E. coli ST131. Our results showed a common occurrence of bacterial contaminants in surface water and an increase in the risk for the dissemination of resistance determinants exacerbated with the ongoing intensified population mobility in Lebanon and the widespread lack of wastewater treatment.

Challenges of post-war policy reforms in Lebanon's water sector – lessons learned

Abstract Lebanon has not been able to properly develop and benefit from its water sources. A confessional system of governance has hindered development of the sector. Laws and regulations have been developed erratically with many superseding others without the superseded laws being erased from the registry. This created a chaotic regulatory and legal environment with overlapping jurisdictions and no clear accountability mechanisms. The period before the onset of the civil war in 1975 witnessed significant progress of both infrastructure and laws and regulations related to the management of the water sector. The civil war destroyed the water sector infrastructure and emptied all regulatory control of the resources. The period of reconstruction between 1990 and 1999 witnessed the promulgation of ambitious reconstruction plans for the water sector with funding reliant on borrowing from local and external debtors. Post 1999, government reforms started creeping into the system but were often donor driven and still suffered from the same mistakes of laws overlain on top of existing laws without erasing the older material. Critically, the management of the sector is not inclusive and the beneficiaries of water services are often not heard and ignored.

Influence of snow cover on water capacity in the Qaraaoun Reservoir, Lebanon

Considerable amount of surface water in Lebanon is stored behind dams, and the Qaraaoun Reservoir (QR) is a typical example. It is the largest surface water body in Lebanon where it irrigates 27,500 ha and generates 22% of Lebanon’s electricity. The reservoir is fed directly from the Litani River which receives water from several springs and from groundwater where both are replenished mainly from snowmelt. However, the relationship between snow cover area on the surrounding mountains and the water volume in the reservoir has not been investigated. This study aims at determining the influence of snow cover area as a water feeding source and the volume of water in the QR. The relationship between these two variables was calculated using satellite images (MODIS-Terra with 500 m spatial resolution) which enable retrieving measures each 8 days, and the in situ measuring instruments fixed in the QR. The investigated period was between 2001 and 2018. Results show that the water volume in the QR is substantially controlled by the snow cover area on the surrounding mountains. It was found that the average time period between snow accumulations on these mountains and the remarkable increase in water level in the QR is about 3 months, while the dynamic changes in snow cover (accumulation/melting) and the induced water level in the reservoir were calculated. In addition snow-water equivalent (SWE) was also determined. This study reveals the significance of snow cover, which either directly feeds the streams or indirectly replenishes the groundwater aquifers where both contribute in the water volume of the QR. Therefore, the catchment mountainous area where snow accumulates should be protected from human interventions which have been lately increased and impacted the hydrologic regime between snow cover and water volume in the QR.

Isopoda (crustacea) from the Levantine sea with comments on the biogeography of mediterranean isopods

This study focuses on the isopod fauna of the eastern Mediterranean, mainly from the waters of Lebanon. Ninety-five samples containing isopods were obtained by scuba diving (depths 0 to 44 m) at 32 stations along the coast of Northern Cyprus, Syria, and Lebanon. The substrates most frequently sampled were caves, vertical walls, and calcareous algae crusts or build-ups. A total of 502 individuals were studied, belonging to 28 species, included in 20 genera, nine families, and three suborders. Four new species from this collection (Atarbolana beirutensis, Cirolana bitari, Cirolana zibrowiusi, Mesanthura pacoi) have already been published. Brief diagnoses and illustrations were included. The collection studied here consists mostly of Mediterranean species, some already known in the area. Ten (eleven, when cf. species is confirmed) are new records in the Levantine Sea (Apanthura addui, Cirolana manorae, Cymodoce fuscina, Cymodoce pilosa, Elaphognathia bacescoi, Gnathia illepidus, Gnathia inopinata, Heptanthura cryptobia, Kupellonura serritelson, Metacirolana rotunda, Pseudocerceis cf. seleneides). Of them, three (four, when cf. species is confirmed) are new records in the Mediterranean Sea (Apanthura addui, Cirolana manorae, Metacirolana rotunda, Pseudocerceis cf. seleneides). Eight species (28.5%) can be considered as non-indigenous (Apanthura addui, Cirolana manorae, Cymodoce fuscina, Metacirolana rotunda, Paracerceis sculpta, Paradella dianae, Pseudocerceis cf. seleneides, Sphaeroma walkeri). This manuscript also provides an inventory of the known Mediterranean isopod fauna (excluding Epicaridea, Oniscidea, and brackish water Aselloidea), which totals 295 species. The isopod fauna of various subregions of the Mediterranean, the Suez Canal, and the Red Sea / Gulf of Aden is compared, and the transit of species through the Suez Canal is discussed. The list of non-indigenous species in the Mediterranaean Sea is updated to 23.

Fluoride concentration of bottled water and public water in Lebanon.

People in Lebanon turned to bottle water consumption because of its poor public water quality. In general, fluoride is known as dental caries preventive. A study in 1986 and two other national surveys in 1994 and 2004 showed that the concentration of fluoride in public Lebanese water was insignificant for the prevention of dental caries (less than 0.3 mg/L). The aim of the study was to measure the fluoride concentration in the highest selling and known commercial brands for bottled water in Lebanon, as well as to assess their effectiveness regarding prevention of dental caries. Fluoride has a notable therapeutic effect but in small doses that fluoride can be found in drinking water. Analysis using an absorptiometry of 625nm and another technique using an Orion electrode of 9609 BN have shown the low content of fluoride in the Lebanese waters (less than 0.3 mg/l). Strategies have recently been evolved based on fluroide supplementation (if the results turn negative) to reduce the index of caries in LEBANON.

Surveys of potato-growing areas and surface water in Lebanon for potato brown and ring rot pathogens.

Field surveys were carried out over three growing seasons (2013–2015), in the main potato growing areas of Lebanon, to assess the occurrence of potato brown rot caused by Ralstonia solanacearum and potato ring rot caused by Clavibacter michiganensis subsp. sepedonicus . A total of 232 potato samples were collected from Bekaa valley and 145 samples from Akkar plain, which are the largest Lebanese areas cropped with potatoes. Composite samples of 200 potato tubers were randomly collected from each field, following procedures laid down in EU legislation. Twelve potato demonstration fields were established in Akkar plain and designed for potato export to European markets: these were also surveyed using the same strategy. Furthermore, a network of 40 sampling sites in Bekaa and 19 sites in Akkar was established to collect surface water. GPS coordinates of potato fields and water sampling sites were recorded to map specific sampling points using Geographic Information System. All samples gave negative results for R. solanacearum and C. michiganensis subsp. sepedonicus in potatoes and R. solanacearum in water, as indicated using the official EU methods for detection and diagnosis for these pathogens. A monitoring system for R. solanacearum and C. michiganensis subsp. michiganensis has been set up in Lebanon. This will increase the phytosanitary quality of potatoes and provide access to broader international markets.

Managerial Efficiency Modeling of Water use in the Republic of Lebanon

Lebanon is one of the few countries in the Middle East with adequate water. Rainfall is relatively plentiful and the country is blessed by several large rivers. But when the residents of Beirut and its surrounding suburbs turn on their water taps, most of the time, nothing trickles out. In summertime, the water supply can be as little as three hours per day for many households, Government negligence, waste water mismanagement, and sanitations are the most problems of the shortage of water in Lebanon. This paper presents a detailed study of the water situation in Lebanon, as the water shortage is a serious problem that affects the life of Lebanese citizens, presented in this paper a detailed budgeting system for the water in Lebanon by measuring incomes from rains, rivers, snow, outcomes from sanitation, waste water, and mismanagement . This paper depends on secondary data as published reports, statistics, and studies by Lebanese governmental agencies, as well as on the Lebanese water strategic planning program of 2010 of the Ministry of Water and Power that helps define different aspects of this research. This paper focuses on the generation of solutions in the near future and the long term as well, and discusses briefly the Lebanese situation using analyzed data. Moreover, the paper’s outcome is cast into a water budget which gives a future prospect for the water situation in Lebanon, and it indicates ways and means to overcome the water shortage in the country.

New Economic Policies: Instruments for Water Management in Lebanon

Social, economic and environmental aspects should be taken into consideration for IWRM implementation in Lebanon. This would be helpful to formulate policies required for improving water sector. Likewise many countries, Lebanon do not implement water policies on the formal level. This is critical since policies are initiative for legislation, strategic planning and operational management. Hence, water resources in Lebanon are threatened by population growth and climatic variability and imbalanced supply/demand. Thus, the interrelation between supplier and consumer should be harmonized since there is large amount of water is lost due non-uniform water supply and partitioning approaches, besides lack of awareness and absence of wise-use of water resources. Therefore, economic policies should be adopted in Lebanon and water pricing must be set to give incentives to user for efficient water use in their various applications. Thus, treating water as an economic good recognizes that water carries an opportunity cost. This paper presents the existing economic status of water in Lebanon in the absence of legal economic policies. It, therefore, extends new Economic Policies Instruments (EPIs) is required for better IWRM.

Exposure assessment of endocrine disruptors in bottled drinking water of Lebanon.

Bisphenol A (BPA) is a commonly used monomer in various products including bottled water. Numerous studies have reported endocrine adverse effects and neoplasia associated with BPA exposure in animals. However, considerable discrepancies exist among these studies with respect to both the nature of the toxic effects and the threshold dose. In Lebanon, 19-L polycarbonate (PC) bottles of drinking water are widely used in urban areas. The present study aims at assessing BPA human exposure and associated health risks from drinking water in Lebanese. A total of 22 bottled water sources, packaged in PC, were identified from licensed and non-licensed sources. Water samples were analyzed following exposure to sunlight for 72 h. BPA in water was quantified by HPLC, and other potential organic pollutants were screened by GC/MS. Fifty-nine percent of samples showed BPA levels above detection limits (>0.05 ng/mL). The median BPA level was 0.1 ng/mL (range 0.05 to 1.37 ng/mL). The mean BPA level for the total number of samples was 0.169 ng/mL (±0.280). A higher mean BPA level was found in water from licensed companies compared to non-licensed sources, however, not statistically significant. Screening showed the presence of dibutyl-phthalate and dioctyl-phthalate in only two samples. Endocrine disruptors (EDR) are ubiquitous contaminants in bottled water in Lebanon with potential health risk implications. Although estimated exposure levels are below the reference dose (RfD), further studies are needed to quantitate exposure from various sources and to investigate EDR contribution to existing epidemics in the country.

The Study of the Groundwater by Using the 34S and 18O of the Sulphates-S18O4 Isotopes

The stable isotope of the sulphur atom ( 34 S) and the 18 O of the sulphates (S 18 O 4 ) give information about the type of the mineralisation of the groundwater existing during the water seepage. The decrease of the concentrations in dissolved SO 4 2− (meq/L) versus the increase of δ 18 O (‰ vs. SMOW) of the sulphates (S 18 O 4 2− ) confirms a partial reduction of the dissolved sulphates in the water. The Under-saturated waters versus the gypsum do not cause the precipitations of the sulphates. The study of δ 34 S (‰ CD) vs. Cl − (mg/L) indicates high variations in δ 34 S (‰ CD) for weak difference in the Cl − (mg/L) content, this is due to the reduction of the dissolved sulphates. Concerning the Jurassic water in Lebanon, an oxidation of the sulphide can take place.

Studying Snowpack-Related Characteristics on Lebanon Mountains

Water resources in Lebanon are witnessing excessive use and demand for water has increased. Surface water is the most exhausted type of water in Lebanon due to the ease of its exploitation. Among examples of surface water, snow has received attention lately because it represents the major source for rivers, springs and groundwater reservoirs. However, the challenges for the water supply make it necessary to investigate the snow cover on the mountainous regions of Lebanon. Therefore, a number of studies have been conducted, but all emphasized the monitoring of snow cover using satellite imagery, while in-situ investigation of snowpack, including the majority of its physical parameters with respect to related characteristics, were not taken into account. This study considers mainly field observations of the snowpack carried out on 280 different sites in the Lebanon mountains. Samples were collected and tested in-situ. The parameters investigated are snowpack density, depth, hardness and surface roughness. The investigated sites were compared according to the following characteristics: altitude, slope, rock hardness, sample timing and sunlight aspect. The study aims to induce different empirical relations between the snowpack properties and the physical setting. This would be a helpful input for further water management measures, notably those concerned with water harvesting, supply and recharge/discharge approaches.

BTES and aldehydes analysis in PET-bottled water in Lebanon

The aim of this study was to determine benzene, toluene, ethylbenzene, styrene (BTES), formaldehyde, acetaldehyde and benzaldehyde in Lebanese polyethylene terephthalate (PET)-bottled water. Aldehydes were analysed by high-performance liquid chromatography with ultraviolet–visible detection (HPLC/UV-vis) after 2,4-dinitrophenylhydrazine (DNPH) derivatisation and solid phase extraction (SPE) concentration, whereas headspace trap gas chromatograph–flame ionisation detector (GC/FID) was used for BTES determination. Both methods were validated according to the NF XP 90-210 and showed good linearity ranging from 3 (limit of quantification [LOQ]) to 15 µg L−1 for BTES and from 20 (LOQ) to 900 µg L−1 for aldehydes. No quantified contamination with BTES, acetaldehyde and benzaldehyde was determined in all analysed fresh Lebanese PET-bottled waters. Formaldehyde was quantified in 3 of the 15 samples at concentrations lower than the maximum contaminant level set by the US Environmental Protection Agency and the World Health Organisation. The samples' exposure to sunlight during 5 months increases the migration of formaldehyde and acetaldehyde. Similar migration increase was observed when the samples were incubated at 40°C during 10 days.

Antimony release in PET bottled natural water in Lebanon

Antimony (Sb) leaching from polyethylene terephthalate (PET) bottling material was assessed in eight registered Lebanese brands of bottled natural water as a function of contact time. The study was performed indoors at 22 °C in the dark and outdoors at a maximum temperature of 45 °C under sunlight. The leached antimony concentration increased with contact time for all of the studied brands except one. The antimony concentration reached 5.5 μg/L after 544 days of contact time with PET packaging. Small bottles with large contact surface area had higher antimony concentration. However, outdoor storage under sunlight at temperatures below 45 °C did not reveal a significant effect on antimony release. Among some physico-chemical parameters studied (pH, calcium, magnesium and bicarbonate), only calcium concentration showed a significant effect on antimony release. The rate of antimony leaching, normalized to the surface to volume ratio of the water bottle, fits the exponential model Sb/(S/V) = 0.562e0.0041t, with R2 = 0.87. Atomic absorption spectroscopy analysis of the different PET packaging material showed an antimony concentration between 80.6 and 352.7 mg Sb/kg PET.

Can Abundance and Scarcity Clash? Environmental Security in Lebanon's Second Republic

This paper examines the ongoing threat to environmental security in Lebanon since the end of the civil war in 1990. It makes the case that there can be environmental causes and effects of conflict, as well as environmental targets of conflict in Lebanon. It examines why the government does not always implement international environmental treaties. The paper studies the hydropolitics of the region, the ominous threat of water wars, and the claims of Syria and Israel on Lebanon’s abundant water. It examines the Wazzani pump dispute that erupted in 2001 when, following Israeli withdrawal, the Lebanese government decided to divert water from the Hasbani River into surrounding impoverished villages. The dispute exemplifies how water tensions, in an area already fueled by political distrust, can easily inflate into war rhetoric. The implications for cooperation with Israel, as well as the role of water in the peace process are also analyzed. As it continues to recover from its 15-year civil war (1975-90), Lebanon, with its limited economic, social and political resources, faces enormous challenges in its struggle for security, given its regional position – located between two powerful neighbors, Syria and Israel – where it bears the consequences of a failed peace process between Israel, the Palestinians, Syria, and of course Lebanon. In the geographical region where Lebanon is situated, environmental issues have been sources of conflict between Arabs and non-Arabs, both in the Near East and Africa. Wars have also contributed to the destruction of the environment in the Arab world. In a region where water is scarce, Lebanon’s neighbors have always claimed its relatively abundant waters. A brief historical overview confirms this. In the Middle East, water conflict is an age-old problem, mentioned as far back as in the Old Testament. The early systematic work of the Zionists for the utilization of the Litani River, which flows within Lebanon and drains not far from Israel, can be traced back to the end of the nineteenth century. During the war of 1948, the new state of Israel occupied Lebanese territory west of its northern tongue to the left bank of the Litani, only to vacate it a few months later partly because of its wrong assumption that water sharing arrangements would be worked out for joint exploitation of the waters of south Lebanon. Since 1949, when Israel and Lebanon signed an armistice agreement, no water arrangements have been put into place by the two neighbors, either through direct negotiation or any other form of formal agreement. As early as 1955, the abundance of water in Lebanon was noticed as a way to alleviate projected water problems in the

Geothermal Water in Lebanon: An Alternative Energy Source

Recently, demand for energy has been increased worldwide, notably in the view of high economic value and competi-tion of fossil fuel, as well as the negative impact of fuel consumption through carbon release, and thus the consequences on human health and environment. Various aspects of energy sources into Earth’s crust have been discovered and utilized. Geothermal energy is one aspect of these sources where they have been well pronounced in many countries and proved to be a potential energy source for the future needs. Lebanon, the country with rare natural energy, the renewable energy sources are almost ignored and there is only limited utilization of hydro-power, wind and solar energy, whilst oil imports occupy a substantial portion for energy use. Yet, geothermal energy has not raised and no concern has been given to this renewable source. Meanwhile, there are several indicators showing the existence of geothermal water in different regions in Lebanon. They almost occur where basalt rocks are exposed. This was evidenced whether from water in drilled wells or from various discharging springs, as well as indications of thermal water was observed also in many localities along the Lebanese coastal water. This study shows the available information in this respect, considering the occurrence of geothermal water in Lebanon as an alternative energy source. Thus four major geothermal domains were recognized. The study introduces detailed characterization on the existing aspects of geothermal water and inducing its hydrologic regime and mechanism of groundwater heating. It would be a reconnaissance stage that may help applying further detailed assessment.

Trihalomethane formation potential in selected drinking waters of Lebanon

Laboratory-scale simulated distribution system trihalomethane (SDS-THM) tests were conducted on selected public drinking water sources to predict as well as evaluate trihalomethane formations under controlled laboratory conditions. Varying concentrations of SDS-total trihalomethane at any time (SDS-TTHMT) (2.68–85.78 μg/L) were detected in the two simulated water sources. Evaluating the impact of each test variable on attained SDS-TTHMT levels revealed that for both water sources, the majority of samples exhibited higher SDS-TTHMT levels in the presence of higher chlorine doses. For the two sources, 85 to 87.5 percent of the sample pairs exhibited higher SDS-TTHMT levels at higher incubation temperatures. Incubation periods at which maximum THM levels were attained varied with water source type as well as pH values. All comparable samples exhibited SDS-TTHMT values higher (1.41 and 7.07 folds) than actual surveyed TTHM levels. Statistically, SDST-TTHM showed significant correlations with applied chlorine dose at the 0.05 level, and with TOC, bromides, contact time, and temperature at the 0.01 level. The predictive model, formulated using multiple regression approaches, exhibiting the highest coefficients of determination was logarithmic for the laboratory simulated THM database (r2=0.70; p<0.001) with a very high significance level (<0.01 level).

Analysis of volatile oil from Nepeta glomerata Montbret et Aucher ex Bentham from Lebanon

Nepeta L., one of the largest genera of Lamiaceae, consists of about 300 species, many of which are pleasantly aromatic, rich in essential oils and of potential economic interest. Several Nepeta species are used in folk medicine as diuretic, diaphoretic, antitussive, antispasmodic, anti-asthmatic, febrifuge, emmenagogue and sedative agents [1]. Nepeta glomerata Montbret et Aucher ex Bentham, catmint, has an aromatic, characteristic odour, which bears a certain resemblance to that of Mint. In this communication we report the study of the essential oil of this plant extracted by hydrodistillation using a Clevenger-type apparatus according to the method recommended in the European Pharmacopoeia [2]. For our study, aerial parts of N. glomerata were collected at the full flowering stage in August 2007 near the Ainnete village, Makmel mountain (1650/1850 a. s.l.), Lebanon. Makmel Mountain is considered as the East's Plateau and Lebanon's water reservoir. The essential oil was analysed by GC and CG/MS: peak identification was accomplished by comparison of their mass spectra with NIST 02 and Wiley 275 libraries and with those reported in literature, as well as by comparison of their retention indices with literature values. Results showed that volatile constituents of N. glomerata consist above all of monoterpenes (41.1%) and sesquiterpenes (28.7%), with a prevalence of oxygenated monoterpenes (22.1%) and oxygenated sesquiterpenes (15.2%). alpha-Pinene (13.4%), spathulenol (8.6%) and carvacrol (5.4%) are the main compounds of the oil.