PB IN TAP WATER IN THE UNIVERSITY DISTRICT, COLUMBUS OH, USA

Lead is a potent toxin that can cause a myriad of health effects, most notably adverse effects in pregnancy and neurological changes in children. Columbus, Ohio, the 15th largest city in the US, with over 900,000 residents has a significant fraction of the public water service lines that contain lead, especially those located in the central (older) parts of the city. We collected tap water samples from buildings on The Ohio State University (OSU) campus and from homes in the surrounding neighborhoods in order to measure the lead (Pb) levels in water, and to determine if the composition of the public service water line contributes to the Pb levels in water. Sampling procedures differed between the campus and household sampling using clean techniques. We collected samples from OSU buildings with different ages (1890 to 2021) from sinks in restrooms and analyzed for major ions, nutrients and Pb. For the household sampling, we collected tap water from kitchen sinks, however, samples for Pb analysis were collected for the 1^st liter and the 5^th liter in order to evaluate Pb contributions from the private versus public water lines.

All Pb measurements in this study were below the EPA trigger level of 15 µg/L. Pb concentrations in tap water on the OSU campus (n=20) ranged from ~ 0.05 to 5.5 ppb with a mean of ~ 1.2 ppb Pb. There was no significant relationship with building age, and while the two oldest buildings sampled (1890’s) were among those with the highest Pb levels (~ 1.5 and 3 µg/L), the two newest buildings (after 2015) had similar Pb levels (~ 1 -2 µg/L). Pb levels from private homes (n=64) were generally lower than those on campus, ranging from undetectable (~ 0.01 µg/L) to 1 µg/L. Most samples had Pb levels less than 0.2 µg/L. Pb concentrations for households with non-Pb service lines showed a small but systematic decrease in Pb concentrations between the 1^st and 5^th liter samples, while those with Pb service lines were more complex, some decreasing, and some showing significant increases. There was no significant difference between Pb concentrations for the Pb vs non-Pb service lines (means ~ 0.12 µg/L Pb) for the 1^st liter samples, while mean Pb concentrations were significantly higher in the 5^th liter samples for Pb service lines, largely due to two outlier concentrations.