A study conducted in Araihazar, Bangladesh, found that exposure to manganese (Mn) through drinking water is associated with reduced intellectual function in 10-year-old children. The study involved 142 children who consumed water with an average Mn concentration of 793 µg/L and arsenic (As) of 3 µg/L. Children underwent medical exams and cognitive assessments using the Wechsler Intelligence Scale for Children, version III (WISC-III). Urine and blood samples were collected to measure Mn, As, and other metals. After adjusting for sociodemographic factors, higher Mn levels in water were linked to lower scores in Verbal, Performance, and Full-Scale IQ. The study found no significant association between low As levels and cognitive function. In the U.S., about 6% of wells exceed the EPA's Mn advisory level of 300 µg/L, suggesting similar risks for children in both countries. Manganese is essential but toxic in excess, with the WHO setting a water Mn standard of 500 µg/L. While occupational Mn exposure is known to cause neurotoxicity, research on children's cognitive effects from water Mn is limited. The study highlights the need for further research on Mn's impact on children's cognitive development, especially in regions with high Mn contamination. The findings suggest that Mn exposure through drinking water may pose a risk to children's intellectual function, emphasizing the importance of monitoring and regulating Mn levels in water sources.A study conducted in Araihazar, Bangladesh, found that exposure to manganese (Mn) through drinking water is associated with reduced intellectual function in 10-year-old children. The study involved 142 children who consumed water with an average Mn concentration of 793 µg/L and arsenic (As) of 3 µg/L. Children underwent medical exams and cognitive assessments using the Wechsler Intelligence Scale for Children, version III (WISC-III). Urine and blood samples were collected to measure Mn, As, and other metals. After adjusting for sociodemographic factors, higher Mn levels in water were linked to lower scores in Verbal, Performance, and Full-Scale IQ. The study found no significant association between low As levels and cognitive function. In the U.S., about 6% of wells exceed the EPA's Mn advisory level of 300 µg/L, suggesting similar risks for children in both countries. Manganese is essential but toxic in excess, with the WHO setting a water Mn standard of 500 µg/L. While occupational Mn exposure is known to cause neurotoxicity, research on children's cognitive effects from water Mn is limited. The study highlights the need for further research on Mn's impact on children's cognitive development, especially in regions with high Mn contamination. The findings suggest that Mn exposure through drinking water may pose a risk to children's intellectual function, emphasizing the importance of monitoring and regulating Mn levels in water sources.