Impacts of iodine factory effluents on the water quality and ecosystem health of Incheh Lagoon in Iran.

Industrial effluents containing heavy metals pose a growing threat to aquatic ecosystems, especially in ecologically sensitive wetlands such as the Incheh lagoon in north- east Iran. In this study, physico- chemical parameters, heavy metal concentrations, and water quality of wastewater from a local iodine production plant discharged into the lagoon are comprehensively analysed. The concentration of 30 heavy metals were measured using flame atomic absorption spectrophotometry (FAAS) and standardised analysis protocols. In particular fluoride (1.36-4.6 mg/L) and manganese (2.25-3.89 mg/L) exceeded the limits set by the US Environmental Protection Agency (USEPA, 2017) and the Water Resources Commission (WRC, 2003). Although Artemia species were present in the lagoon, their short residence time and relatively low metal accumulation compared to FAO/WHO guidelines indicated minimal risk to migratory bird populations. Uncontrolled drainage channels have been identified as the main source of contamination. To tackle this problem, the study recommends joint actions involving forest authorities, municipal bodies and local stakeholders to introduce sustainable watershed management practices.