This research investigates the presence of heavy metals that cause contamination in untreated wastewater that is used for crop irrigation in Al-Nassariya, Jeftlek, and Jordan Valley, in the main breadbasket farming area, northeast of Nablus city in the West Bank, Palestine. The valley is considered the main source of fruits, vegetables, and grains for the people of Nablus, because of its heavy production for the local market. This makes the water quality in this area a direct concern for public health and food safety.
Water samples were collected from three areas: a clean groundwater stream, a polluted wastewater stream carrying untreated sewage and industrial discharge from Nablus city, and a mixed stream where both combine. Samples were collected during two seasons (winter rainy season and summer season) and they were analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) at An-Najah National University. Results were compared against FAO international standards for safe irrigation water.
During winter, most toxic heavy metals were found to be within safe limits. However, during summer, six heavy metals, that are: arsenic, chromium, cadmium, copper, nickel, and iron, were tested as exceeding safe FAO limits. This confirms that the water causes a serious risk to the quality of crops harvested from there, and human health during the summer season.
To provide a solution for this water problem, we developed an activated carbon filter made from coffee waste to function as an affordable and sustainable solution. The filter has proven to have reduced toxic heavy metal contaminants closer to the safe FAO limits, with removal rates between 55% and 90%.
This demonstrates that the coffee-waste activated carbon filter alternative developed by the researchers, is a sustainable and cheap alternative for contaminated irrigation water that farmers use in that area.
