Taş Divrik 2025 — Toxic elements in drinking fountains, Şarkışla, Sivas, Turkey
This 2025 study investigated physicochemical variables and toxic metal concentrations in drinking water from five publicly used fountains in Şarkışla, Sivas Province, Turkey, sampled across all four seasons in 2022. Arsenic concentrations far exceeded drinking water limits at all stations in all seasons, driven by naturally occurring contamination from Pliocene alluvial aquifer deposits. Human health risk assessment (HHRA) for ingestion and dermal pathways found that As poses serious carcinogenic risk exceeding the 1×10−4 threshold for both adults and children; Cd posed non-carcinogenic hazard index values above 1 at several stations.
Key numbers
Seasonal arsenic concentrations (ppb, all stations, selected values from Table 3):
- Spring: 793–1035 ppb across 5 stations
- Summer: 968–1121 ppb
- Autumn: 1102–1323 ppb
- Winter: 1106–1308 ppb
WHO/Turkish drinking water limit for As: 10 ppb. All measured values exceed this limit by approximately 80–130-fold.
Cadmium concentrations (ppb):
- Spring: 0.093–0.311 ppb
- Summer: 0.093–0.311 ppb
- Autumn: 0.062–9.77 ppb (station 4 autumn: 9.77 ppb — notably elevated)
- Winter: 0.124–6.35 ppb
WHO limit for Cd: 3 ppb. The autumn/winter high values at stations 2 and 4 exceed limits.
Manganese concentrations (ppb): 8.43–10.27 ppb (spring/winter) rising to 28.54–87.27 ppb (summer), exceeding the 50 ppb WHO guideline value in summer at multiple stations.
Copper: 0.74–1.47 ppb, well below limits. Zinc: 1.04–6.71 ppb, below limits.
Carcinogenic risk (CR): As CR via ingestion exceeded the 1×10−4 acceptable threshold for both children and adults at all stations in all seasons. Cd CR was near the threshold at high-concentration stations.
Hazard index: HI for Cd exceeded 1 at multiple station-season combinations through ingestion and dermal exposure combined.
Nitrate Pollution Index (NPI): slight contamination. Groundwater Quality Index (GWQI): no contamination overall.
Methods (brief)
Water samples collected seasonally following APHA methods, transported cold chain with 0.1 N HNO3 acidification to pH < 2. As, Cd, Zn, Mn, Cu analyzed by ICP-MS at accredited Sivas Cumhuriyet University Advanced Technology Research Center (CÜTAM). Triplicate analyses, mean values reported in ppb. HHRA using CDI ingestion and dermal equations per US EPA guidance. NPI and GWQI calculated per standard formulas. Spatial mapping via ArcMap 10.3.1.
Implications
Certification: Demonstrates that naturally occurring arsenic in groundwater-fed drinking fountains in Central Anatolia reaches extreme concentrations (up to ~1300 ppb), far above any regulatory limit. Not directly relevant to food matrix certification but relevant to irrigation water quality as a contamination driver.
Courses: Illustrates the geogenic (naturally occurring) pathway for arsenic contamination; quaternary alluvial and Pliocene aquifer layers concentrate As without anthropogenic input. Useful for teaching source-differentiation of heavy metal contamination in water.
App: Not directly applicable; drinking water composition is not an ingredient. Potentially relevant to irrigation-water-driven soil and crop contamination modeling.
Microbiome: Not addressed.