An-Najah Staff

Background Radon gas is considered as a main risk factor for lung cancer and found naturally in rock, soil, and water. The objective of this study was to determine the radon level in the drinking water sources in Nablus city in order to set up a sound policy on water management in Palestine.
Methods This was a descriptive study carried out in two phases with a random sampling technique in the second phase. Primarily, samples were taken from 4 wells and 5 springs that supplied Nablus city residents. For each source, 3 samples were taken and each was analyzed in 4 cycles by RAD 7 device manufactured by Durridge Company. Secondly, from the seven regions of the Nablus city, three samples were taken from the residential tap water of each region. Regarding the old city, ten samples were taken. Finally, the mean radon concentration value for each source was calculated.
Results The mean (range) concentration of radon in the main sources were 6.9 (1.5-23.4) Becquerel/liter (Bq/L). Separately, springs and wells' means were 4.6 Bq/L and 9.5 Bq/L; respectively. For the residential tap water in the 7 regions, the results of the mean (range) concentration values were found to be 1.0 (0.9-1.3) Bq/L. For the old city, the mean (range) concentration values were 2.3 (0.9-3.9) Bq/L.
Conclusions Except for Al-Badan well, radon concentrations in the wells and springs were below the United State Environmental Protection Agency maximum contaminated level (U.S EPA MCL). The level was much lower for tap water. Although the concentration of radon in the tap water of old city were below the MCL, it was higher than other regions in the city. Preventive measures and population awareness on radon's exposure are recommended.

A set of established precautions and procedures must be followed to ensure water quality in rainwater harvesting cisterns. In this study, 106 cisterns were sampled and 176 cistern owners were surveyed in the northern West Bank region. It was found that although the nitrate concentration and Total Dissolved Solids (TDSs) readings of the sampled cisterns conformed to Palestinian standards, most cisterns were found to contain fecal coliform, exceeding 8000 cfu/ml in many cases. Cistern owners responses revealed an array of malpractices, which are suspected of leading to this contamination risk. Several remedial actions were proposed to alleviate this condition.

Chlorination of drinking water from natural sources results in the formation of several organic compounds as disinfection by products. The most widely studied among them is a group of compounds collectively called trihalomethanes (THMs), some of which are reported to be toxic for human consumption. Consequently water supply authorities in some countries are forced to resort to costly corrective measures in order to reduce their levels below the maximum concentration limits (MCL) set by the environmental protection and health authorities. It is well established by now that the formation of such compounds is due to reactions between chlorine and some precursor organics originally present in raw water. In the City of Nablus which located in the northern West Bank- Palestinian Territory, a water system network serves about 177,000 people in Nablus and its surrounding localities, consist of, four wells, five springs, nine operating storage tanks,13 pump stations, distribution network consists of about 279 km of water pipes of different diameter, material and ages, The treatment process used for disinfecting drinking water is chlorination, by using sodium hypochlorite, the Unaccounted for Water (UFW) is over 30% and the supply is intermittent due to water shortages, so contaminants can intrude into the pipe network and the rooftop storage tanks and react with chlorine to form disinfection by – products (DBPs), which may cause cancer and some other diseases.

Samples of drinking water were collected from several villages in Nablus area, and from the city of Hebron. The concentrations of lead,copper,nickle,manganese,iron,zinc,magnesium and calcium were determined in these samples using flame atomic absorbtion  Spectoscopy.The obtained results were compared with the maximum allowed limit of concentration for e'ach of these elements in drinking water.

Metal concentrations in drinking water used in Nablus have been studied . Samples from houses located in various districts of Nablus have been collected between Dec . 22,1985, and Jan . 19,1986 , acidified and then analysed for their metal content of the elements lead , copper , zinc , nickel , iron , manganese , calcium and magnesium using flame atomic absorption spectroscopy with an acetylene—air flame The results showed that the concentrations of lead , copper , nickel , iron and manganese were well below the safe limits . The concentrations of both zinc and magnesium were high but still below the maximum limit allowed in drinking water . The concentration of calcium was found always above the allowed limit . The effect of storing water in tanks ( this is very common in Nablus ) on the concentration of the above elements has been studied . The only effect found for storing water in tanks was a decrease in the concentration of zinc from water . No effect was found for using sun—heaters on the concentrations of the above elements in water .