Abstract
This study was conducted to evaluate the quality of drinking water in the Department of Dar Al-Fawakeh through its physical, chemical and biological characteristics, as well as to estimate the concentration of some heavy elements during September 2024. The pH, total dissolved solids (TDS), electrical conductivity (EC), temperature (TºC), turbidity (TNU), major cations (calcium Ca
2⁺
, magnesium Mg
2⁺
, sodium Na
+
, potassium K
+
and ammonium NH
4
+
), major anions (phosphate PO
4
-3
, sulfate SO
4
2-
, nitrate NO
3
-
, bicarbonate HCO
3
⁻
, chloride Cl
⁻
, and fluoride F
⁻
) were measured, along with some heavy metals (lead Pb, iron Fe, copper Cu, and zinc Zn) from well water samples taken from sixteen (16) identified locations in the study area of Dar Al-Fawakeh Department, namely: Amzwair Madamqun, Makalan, Kelkite, Arbouguine, Ardebe, Foutoulkan, Omol (1), Mata, Djabal-annour, Hadjer-Madine, Amzwair Acimenti, Kokar, Tiktike, Migneri, Omol (2), and Am zwair Arrouhal. The samples were analyzed and the results were compared with the World Health Organization (WHO), European Union (EU) and the Chadian drinking water standards (C.S). The study revealed very high turbidity values (95, 91, 89.03, and 21.87 NTU) in the wells of Makalan, Madamqun, Kelkite, and Foutoulkan, respectively. These values exceeded the permissible turbidity limit (5 NTU) set by the WHO and the EU. The cation analysis revealed varying concentrations of calcium ions (Ca
2⁺
), including the value180.8 mg/L that exceeding the Chadian standard (100 mg/L). Ammonium ions (NH
4
+
) reached a concentration of 1.02 mg/L, exceeding the WHO limit (0.5 mg/L). The anion analysis also showed high levels of bicarbonate (605.12 mg/L), phosphate (1.53 mg/L), and fluoride (2.67 mg/L). All these anions exceeded the WHO and Chadian standards, which are 200, 0.1 and 0.7 mg/L respectively. The results of heavy metal analyses showed high levels of lead (0.61 mg/L) and iron (1.03 mg/L) in the Tiktike and Am zwair Ar-rohal wells, respectively. These levels exceeded the permissible limits for lead (0.01 mg/L) and iron (0.3 mg/L) according to WHO) and Chadian standards (0.05 mg/L). Microbiological analyses also confirmed very high levels of microbiological contamination exceeding the WHO limits. Turbidity is an indicator of poor water quality and provides a fertile environment for microbial growth and the development of gastrointestinal diseases (diarrhea, dysentery, cholera) and other parasitic infections. Fluoride exposure leads to fluorosis (reddened teeth), skeletal fluorosis, osteoporosis in children and adults, and bone deformities, particularly in the legs, knees, and hips. Even small amounts of lead can cause cancer, kidney and nervous system inflammation, brain damage, anemia, severe constipation, vomiting, and general neurological disorders, headaches, paralysis, coma, impaired cognitive function, reduced intelligence, and aggressive behavior. These analyses indicate that most of the water in these wells is contaminated and unfit for drinking, negatively impacting the health of population and consequently their social and economic well-being.