Water quality of the King Abdullah Canal/Jordan–impact on eutrophication and water disinfection

The King Abdullah Canal (KAC) is an artificial water conveyor serving as raw water source for drinking water supply of Amman and for irrigation purposes in the Jordan Valley. The main water sources for KAC originate from the Yarmouk River, the Mukheiba Wells, and the Peace Conveyor. Water samples were collected from December 2002 to May 2004 to investigate changes in physicochemical parameters and parameters related to eutrophication along KAC. The catchment area of KAC is highly heterogeneous in terms of topography, climate, geologic conditions, and land use, resulting in great variations in the physicochemical composition of the canal water. The Yarmouk River and the Mukheiba Wells reflect the water quality of precipitation without much dissolution of halides, whereas the Peace Conveyor shows a groundwater characteristic. Main dischargers of N and P compounds are the Yarmouk River, and dams and wadis along KAC. The concentrations in the canal are mostly above eutrophication level for N and P. Along KAC there is an increase in chlorophyll a concentration and plankton counts. The formation potentials for trihalomethanes (THMs) and for integrated organically bound halogens are determined by chlorination to evaluate the consequences of water disinfection. Due to relatively high bromide concentration mainly brominated THMs are formed.     

Quantitative cancer risk assessment and local mortality burden for ambient air pollution in an eastern Mediterranean City

Health risks posed by ambient air pollutants to the urban Lebanese population have not been well characterized. The aim of this study is to assess cancer risk and mortality burden of non-methane hydrocarbons (NMHCs) and particulates (PM) based on two field-sampling campaigns conducted during summer and winter seasons in Beirut. Seventy NMHCs were analyzed by TD-GC-FID. PM_2.5 elemental carbon (EC) components were examined using a Lab OC-EC aerosol Analyzer, and polycyclic aromatic hydrocarbons were analyzed by GC-MS. The US EPA fraction-based approach was used to assess non-cancer hazard and cancer risk for the hydrocarbon mixture, and the UK Committee on Medical Effects of Air Pollutants (COMEAP) guidelines were followed to determine the PM_2.5 attributable mortality burden. The average cumulative cancer risk exceeded the US EPA acceptable level (10⁻⁶) by 40-fold in the summer and 30-fold in the winter. Benzene was found to be the highest contributor to cancer risk (39–43%), followed by 1,3-butadiene (25–29%), both originating from traffic gasoline evaporation and combustion. The EC attributable average mortality fraction was 7.8–10%, while the average attributable number of deaths (AD) and years of life lost (YLL) were found to be 257–327 and 3086–3923, respectively. Our findings provide a baseline for future air monitoring programs, and for interventions aiming at reducing cancer risk in this population.

     

Five-year monitoring study of chemical characteristics of Wet atmospheric precipitation in the southern region of Jordan

Wet atmospheric samples were collected from different locations in the southern region of Jordan during a 5-year period (October 2006 to May 2011). All samples were analyzed for pH, EC, major ions (Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃ ^?, Cl^?, NO₃ ^?, and SO₄ ^2?), and trace metals (Fe²⁺, Al³⁺,Cu²⁺, Pb²⁺, and Zn²⁺). The highest ion concentrations were observed during the beginning of the rainfall events because large amounts of dust accumulated in the atmosphere during dry periods and were scavenged by rain. The rainwater in the study area is characterized by low salinity and neutral pH. The major ions found in rainwater followed the order of HCO₃?>?Cl^??>?SO₄ ^2? and Ca²⁺?>?Na⁺ > Mg²⁺ > NH₄ ⁺ > K⁺. Trace metals were identified to be of anthropogenic origin resulting from cement and phosphate mining activities located within the investigated area and from heating activities during the cold period of the year (January to April). The wet precipitation chemistry was analyzed using factor component analysis for possible sources of the measured species. Factor analysis (principal component analysis) was used to assess the relationships between the concentrations of the studied ions and their sources. Factor 1 represents the contribution of ions from local anthropogenic activities, factor 2 represents the contribution of ions from natural sources, and factor 3 suggests biomass burning and anthropogenic source. Overall, the results revealed that rainwater chemistry is strongly influenced by local anthropogenic sources rather than natural and marine sources, which is in a good agreement with the results obtained by other studies conducted in similar sites around the world.     

Speciation of non-methane hydrocarbons (NMHCs) from anthropogenic sources in Beirut,Lebanon

The chemical composition of emissions from the different anthropogenic sources of non-methane hydrocarbons (NMHC) is essential for modeling and source apportionment studies. The speciated profiles of major NMHC sources in Lebanon, including road transport, gasoline vapor, power generation, and solvent use were established. Field sampling have been carried out by canisters in 2012. Around 67 NMHC (C2 to C9) were identified and quantified by using a gas chromatograph equipped with a flame ionization detector. Typical features of the roadway emissions included high percentages of isopentane, butane, toluene, xylenes, ethylene, and ethyne. Gasoline evaporation profiles included high percentage of the C4–C5 saturated hydrocarbons reaching 59 %. The main compounds of the power generator emissions are related to combustion. Toluene and C8–C9 aromatics were the most abundant species in emissions from paint applications. Finally, the impact of the use of region-specific source profile is tackled regarding the implication on air quality.