Groundwater contamination with heavy metals: A case study in Hebron, Palestine

The study aims to identify seasonal fluctuations in groundwater quality concerning heavy metal contamination. Specifically, it assesses heavy metal concentrations in groundwater in Wadi Al-Samen, evaluates its suitability for drinking purposes, and compares these levels with the World Health Organization standards. Groundwater samples were collected from 20 wells over two seasons and analyzed for 16 trace elements using atomic absorption spectrometry. The metals analyzed include barium, molybdenum, iron, cobalt, cadmium, chromium, boron, lithium, aluminum, arsenic, manganese, nickel, copper, zinc, lead, and selenium. Results showed that four samples exceeded the permissible limits for barium and lithium in both seasons, three samples exceeded the recommended zinc limits in both seasons, 17 samples exceeded the permissible selenium limit in the dry season, and 15 in the wet season, while one sample exceeded the recommended copper limit in both seasons. The heavy metal pollution index (HPI) and metal index (MI) were used to assess contamination levels. HPI values exhibited significant spatial variations, with recorded values of 17.2 in the dry season and 11.99 in the wet season, both below the critical threshold of 100. Groundwater quality was classified as poor in the Al-Hejreh well and very poor in the Al-Fawwar1 well, rendering it unsuitable for drinking. MI results indicated moderate heavy metal contamination, with mean MI values of 2.3 in the dry season and 2.2 in the wet season. The heavy metals detected in the study area were categorized into toxic elements, alkaline earth metals, alkali metals, transition metals, other metallic elements, and non-metallic elements. This research highlights groundwater contamination in Wadi Al-Samen and underscores the need for mitigation measures to reduce health risks for local residents.