John E. Tobiason

Exposure to lead through drinking water is of concern for children, particularly at schools and early education and care facilities (EECFs), where they spend much of their time. We use lead and copper data from monitoring in schools and EECFs in Massachusetts (USA) and create risk indices based on the percentage of fixtures in a school above three water lead level (WLL) thresholds (15, 5, and 1 ppb) to model which building characteristics, water source, and water treatment practices are associated with a school exceeding these thresholds. Local building characteristics had larger effects than information about the public water supplier (PWS), and buildings built from 1950 to 1980 were most at risk. Daily flushing and fixture replacement often decreased elevated WLLs, and water coolers had lower WLLs than other fixtures. These findings highlight the value of WLL monitoring programs and can be used to prioritize future investment in monitoring and remediation.

The objective of this study was to determine the influence of manganese oxide (MnOx) coated granular media on disinfection byproduct (DBP) formation for dissolved manganese (Mn(II)) and natural organic matter (NOM) concentrations typical in drinking water treatment (DWT). Instantaneous and 24‐h haloacetic acid and total trihalomethane concentrations of influent and effluent samples from two DWT plants, one using MnOx‐coated dual media (DM) filters and the other using second‐stage contactors for Mn(II) sorption by coarse MnOx‐coated ceramic media after DM filtration, were examined. Results showed that interaction with MnOx‐coated surfaces did not increase measured DBP concentrations. Observed increases in 24‐h DBP concentrations for the surface water plant were attributed to filter‐associated NOM, and not the MnOx coating. The findings of this study indicate that a second‐stage contactor – with MnOx‐coated media utilized for Mn(II) removal after a particle removal filter – does not increase DBP formation under typical treatment conditions.