Hormones and Pharmaceuticals in Groundwater Used As a Source of Drinking Water Across the United States

This is the first
large-scale, systematic assessment of hormone
and pharmaceutical occurrence in groundwater used for drinking across
the United States. Samples from 1091 sites in Principal Aquifers representing
60% of the volume pumped for drinking-water supply had final data
for 21 hormones and 103 pharmaceuticals. At least one compound was
detected at 5.9% of 844 sites representing the resource used for public
supply across the entirety of 15 Principal Aquifers, and at 11.3%
of 247 sites representing the resource used for domestic supply over
subareas of nine Principal Aquifers. Of 34 compounds detected, one
plastics component (bisphenol A), three pharmaceuticals (carbamazepine,
sulfamethoxazole, and meprobamate), and the caffeine degradate 1,7-dimethylxanthine
were detected in more than 0.5% of samples. Hydrocortisone had a concentration
greater than a human-health benchmark at 1 site. Compounds with high
solubility and low Koc were most likely
to be detected. Detections were most common in shallow wells with
a component of recent recharge, particularly in crystalline-rock and
mixed land-use settings. Results indicate vulnerability of groundwater
used for drinking water in the U.S. to contamination by these compounds
is generally limited, and exposure to these compounds at detected
concentrations is unlikely to have adverse effects on human health.