Manganese (Mn) is essential in growth and development, yet higher levels of Mn are associated with deficits in neurodevelopment. Elevated air Mn was identified near Mn alloy processing facilities in Southeast Side Chicago resulting in community concern about child exposure and health. Blood, hair, and soil samples were collected and analyzed for multiple metals for children ages 7-17 years and a parent/primary caregiver completed surveys. We used generalized estimating equations to assess associations between metals and the Adaptive Behavior Assessment System 3rd Edition (ABAS-3) scores. Sensitivity analyses were conducted to determine effect modification by child sex on associations between metals and ABAS-3 scores. Bayesian kernel machine regression was used as our principal analytic framework to assess the associations between metal mixtures and adaptive behaviors. The analyses included 108 children. Residential distance from the nearest Mn industrial source was inversely correlated with soil Mn levels and some were above the federal screening level. A significant association was found between soil Mn and lower ABAS-3 score (β: 3.78, 95 % CI: 7.31, -0.25), and between blood Mn and lower scores in females (β: 11.8, 95 % CI: 21.7, -1.87). ABAS-3 scores were negatively associated with the blood metals mixture, primarily driven by Mn. Children in Southeast Side Chicago have elevated levels of soil Mn and soil Mn was associated with poorer ABAS-3 scores. Sex-specific differences were found between metal levels and ABAS-3 scores. After considering multiple metals in mixture, Mn was the primary driver of poorer adaptive behavior.

Deficiency or excess exposure to manganese (Mn), an essential mineral, may have potentially adverse health effects. The kidneys are a major organ of Mn site-specific toxicity because of their unique role in filtration, metabolism, and excretion of xenobiotics. We hypothesized that Mn concentrations were associated with poorer blood pressure (BP) and kidney parameters such as estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), and albumin creatinine ratio (ACR). We conducted a cross-sectional analysis of 1931 healthy U.S. adolescents aged 12–19 years participating in National Health and Nutrition Examination Survey cycles 2013–2014, 2015–2016, and 2017–2018. Blood and urine Mn concentrations were measured using inductively coupled plasma mass spectrometry. Systolic and diastolic BP were calculated as the average of available readings. eGFR was calculated from serum creatinine using the Bedside Schwartz equation. We performed multiple linear regression, adjusting for age, sex, body mass index, race/ethnicity, and poverty income ratio. We observed null relationships between blood Mn concentrations with eGFR, ACR, BUN, and BP. In a subset of 691 participants, we observed that a 10-fold increase in urine Mn was associated with a 16.4 mL/min higher eGFR (95% Confidence Interval: 11.1, 21.7). These exploratory findings should be interpreted cautiously and warrant investigation in longitudinal studies.