Assessment of Heavy Metal Contamination and Non-Carcinogenic Health Risk in Qanat Water, Agricultural Soil, and Plantago lanceolata in South Khorasan Province, Iran

Zahedygol, Morteza; Rezaei, Mohammad Reza; Sayadi, Mohammad Hossein; Kharkan, Javad

doi:10.48308/set.2026.245796.1206

Assessment of Heavy Metal Contamination and Non-Carcinogenic Health Risk in Qanat Water, Agricultural Soil, and Plantago lanceolata in South Khorasan Province, Iran

Articles in Press

Document Type : Original Research Article

Authors

Morteza Zahedygol ¹

Mohammad Reza Rezaei ¹

Mohammad Hossein Sayadi ²

Javad Kharkan ¹

¹ Department of Environmental Engineering, Faculty of Natural Resources and Environment, University of Birjand, Birjand, Iran

² Iranian National Institute for Oceanography and Atmospheric Science (INIOAS), Tehran 1411813389, Iran

10.48308/set.2026.245796.1206

Abstract

Qanats are important sources of drinking water and irrigation in arid regions of Iran. This study assessed heavy metal contamination and non-carcinogenic health risks in qanat water, agricultural soils, and Plantago lanceolata in South Khorasan Province, Iran. Water, soil, and P. lanceolata samples were collected from nine representative qanats during autumn. Cadmium (Cd), chromium (Cr), arsenic (As), and nickel (Ni) were measured using HR-CS AAS. Non-carcinogenic risks were assessed using the USEPA methodology by calculating Hazard Quotients (HQs) and Hazard Indices (HIs) for adults and children through three exposure pathways: drinking water, soil, and medicinal plant consumption. Mean concentrations of Cd, Cr, As, and Ni in qanat water were 0.026, 1.038, 0.912, and 3.610 µg/L, respectively, all below WHO guideline values. Chromium had the highest mean concentration in soil (101.79 mg/kg). Metal concentrations in P. lanceolata were generally below applicable guideline values. The mean HI values associated with drinking water ingestion were 0.451 for adults and 1.052 for children. The total HI values across three pathways were 0.553 for adults and 1.894 for children. Arsenic was the primary risk driver in the water pathway, while chromium was the primary risk driver in the soil pathway. Although qanat water generally complied with drinking-water standards, the elevated HI in children highlights the need for continuous monitoring of qanat water, agricultural soils, and medicinal plants to protect public health.

Keywords

Arsenic

Chromium

Human health risk

Heavy metals

Plantago lanceolata

Subjects