en عمومى General مقاله اصیل Original Article <div style="text-align: justify;">Background: This study aimed to determine the spatial assessment and risk assessment of three widely used pesticides, chlorpyrifos (CPF), malathion, and diazinon, in the tap water distribution network and surface water of Ardabil Province, northwest Iran.<br> Methods: Sampling was conducted at 41 points in the water distribution network and 30 surface water points. Pesticide values were detected by gas chromatograph-flame ionization detector (GC-FID) after solid-phase extraction.<br> Results: The ranking of pesticide compounds in tap water was CPF > malathion > diazinon. The mean concentrations of CPF, malathion, and diazinon in surface water were found to be 0.006, 0.013, and 0.003 mg/L, respectively. The highest pesticide concentrations were detected in the northeast region. CPF concentrations exceeded the maximum concentration level (MCL) in 7% of tap water samples.<br> Conclusion: Based on USEPA standards, the average non-carcinogenic health risks from exposure to pesticides through water consumption remained within the acceptable limits, with a hazard index (HI) below 1 (HI < 1 indicates &ldquo;acceptable risk&rdquo; per USEPA). Sensitivity analysis indicated that CPF<br> concentration and the exposure duration to malathion had the most significant influence on chronic daily intake (CDI) and potential noncancer health effects. Although pesticide levels in drinking water mostly stayed within safe limits, concentrations in the northern region exceeded permissible levels. Therefore, further efforts are essential to regulate pesticide contamination and reduce related health risks in the future.</div> Drinking water, Pesticides, Risk assessment, Water supply, Iran 1 11 http://ehemj.com/browse.php?a_code=A-10-1-423&slc_lang=en&sid=1 Zahra Atafar zahra.atafar@gmail.com 100319475328460021189 100319475328460021189 No Research Center for Environmental Determinants of Health (RCEDH), Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran Amir Mohammadi mohammadiurm@gmail.com 100319475328460021190 100319475328460021190 No Social Determinants of Health Research Center, Clinical Research Institute, Urmia University of Medical Sciences, Urmia, Iran Abdollah Dargahi a.darghahi29@yahoo.com 100319475328460021191 100319475328460021191 No Department of Environmental Health, Khalkhal University of Medical Sciences, Khalkhal, Iran Mehdi Vosoughi Niri mvn_20@yahoo.com 100319475328460021192 100319475328460021192 No Social Determinants of Health Research Center, Ardabil University of Medical Sciences, Ardabil, Iran Niloufar Hashemi Danesh niloufar.hdanesh@gmail.com 100319475328460021193 100319475328460021193 No Department of Clinical Pharmacy, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran Tayebe Sadeghi sadeghi.tayebe@gmail.com 100319475328460021194 100319475328460021194 Yes Correspondence to: Department of Environmental Health, School of Health, Ardabil University of Medical Sciences, Ardabil, Iran Ahmad Mokhtari s.a.mokhtari@gmail.com 100319475328460021195 100319475328460021195 No Department of Environmental Health, School of Health, Ardabil University of Medical Sciences, Ardabil, Iran Hadi Sadeghi hsadeghi1079@gmail.com 100319475328460021196 100319475328460021196 No Department of Environmental Health, School of Health, Ardabil University of Medical Sciences, Ardabil, Iran Morteza Alighadri m.alighadri@arums.ac.ir 100319475328460021197 100319475328460021197 No Department of Environmental Health, School of Health, Ardabil University of Medical Sciences, Ardabil, Iran Anoshirvan Sedigh a.sadigh46@gmail.com 100319475328460021198 100319475328460021198 No Department of Environmental Health, School of Health, Ardabil University of Medical Sciences, Ardabil, Iran