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Hebron aquifer contamination with heavy metals

above 3 mg/L may have an undesirable astringent taste, typically enters water sources through industrial and
opalescent appearance, and form a greasy film when domestic effluents.
boiled. High zinc intake can cause fever, nausea, In Wadi Al-Samen, the maximum boron (B)
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vomiting, stomach cramps, and diarrhea, along with concentration during the dry season was 0.051 mg/L,
gastric erosion and gastrointestinal disorders. 72 with an average of 0.0215 mg/L. In the wet season, boron
A study by Al-Zaarir indicated that copper, barium, concentrations ranged from zero to 0.048 mg/L, with an
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or zinc levels did not exceed the permissible limits for average of 0.019 mg/L. No boron levels exceeded the
groundwater samples. The permissible level of zinc is permissible limits in either season.
3 mg/L, as established by the WHO. The concentrations Selenium (Se) is a naturally occurring element found
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of zinc in the dry season ranged from zero to 7.42 mg/L, in rocks, soil, plants, and water. Public health standards
with an average of 1.04 mg/L. Out of 20 analyzed for safe selenium levels in drinking water vary widely,
samples, 3 samples exceeded the permissible limits in but the WHO recommends a permissible level of
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both seasons (Figure 7). Elevated zinc levels in Karaza, 0.04 mg/L. Selenium can enter groundwater through the
Abdo, and Al-Alaqa Al-Tahta wells are likely due to weathering of selenium-rich rocks and soil, often leaching
the burning of wires and cables to retrieve copper. This into groundwater due to irrigation and rainfall. While
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highlights the need for proper waste management to small amounts of selenium are beneficial, excessive
protect human health and the environment. levels can be toxic. Potential health effects associated
Cadmium was not detected in significant with selenium overexposure include hair and fingernail
concentrations in either season. The WHO permissible loss, as well as numbness in the fingers and toes. 7
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level for cadmium is 0.003 mg/L. In this study, selenium concentrations during the dry
Iron was detected in 0.1% of the groundwater sample. season ranged from 0.018 to 0.64 mg/L, with an average
The WHO permissible level of iron in drinking water is of 0.10 mg/L. The maximum selenium concentration
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2 mg/L. In Wadi Al-Samen, the maximum recorded iron in the wet season was 0.062 mg/L, with an average of
concentration during the dry season was 0.143 mg/L, 0.047 mg/L. Higher-than-permissible selenium levels
with an average of 0.0167 mg/L. were observed in 0.85% of samples in the dry season
No samples exceeded the permissible limit for and 0.75% in the wet season.
chromium concentrations. The maximum chromium The WHO permissible level of aluminum in
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concentration in the dry season was 0.001 mg/L, with an drinking water is 0.9 mg/L. The maximum aluminum
average of 0.00005 mg/L. Chromium was not detected concentration in Wadi Al-Samen during the dry season
during the wet season in any of the study locations. The was 0.084 mg/L, with an average of 0.03 mg/L. The
WHO permissible level of chromium is 0.05 mg/L. concentration of aluminum during the wet season
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ranged from 0 to 0.081 mg/L, with an average of
3.3.6. Non-metallic elements (boron, selenium, and 0.03 mg/L. None of the 20 analyzed samples exceeded
aluminum) the permissible limit of aluminum. Chemical processes
The WHO permissible level of boron in drinking such as carbonate/phosphate dissolution, oxidation/
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water is 2.4 mg/L. Long-term human exposure to boron reduction reactions, along with agricultural practices
compounds can cause gastrointestinal irritation. Boron (e.g., fertilizer application and irrigation) are likely
contributors to groundwater self-pollution, as observed
in Al-Zarqa Amman Basin in Jordan. 75
Historically, these wells were considered clean;
however, increasing contamination from human
activities, industrial waste, sewage, and excessive
groundwater pumping has degraded water quality.
A study by Zaarir reported no exceedance of threshold
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limits for copper, zinc, and barium in groundwater wells
in the study area.

4. Conclusion

Figure 7. Zinc concentrations in samples from two Wadi Al-Saman is a crucial groundwater recharge
sampling rounds. Data are presented as actual values. source for the Western Basin, which flows toward the

Volume 22 Issue 2 (2025) 59 doi: 10.36922/AJWEP025040020