Use of Passive Samplers to Evaluate Pharmaceutical Fate in Surface Waters

Emerging contaminants have been of importance in recent water research. Wastewater treatment plants (WWTPs) have proved ineffective at handling present-day antibiotic loads from hospital and municipal sources. Kolpin et al. (2002) performed a study that identified pharmaceuticals in numerous waters downstream from effluent discharge. Though present in trace levels, concern has been raised regarding pharmaceutical persistence in natural environments. In the present study, uptake rates were quantified in the laboratory for 25 pharmaceutical compounds using Polar Organic Chemical Integrative Samplers (POCIS). Twenty new uptake rates were determined for compounds that have no previously reported literature values. POCIS was also used to evaluate the fate of polar organic contaminants in Nebraska surface waters impacted by WWTP effluent. Select pharmaceuticals were observed to persist for at least 1300 m downstream. Carbamazepine and DEET showed persistence and the highest average concentrations of 110 and 60 ng/L, respectively. Decay rates were determined for 25 pharmaceuticals in receiving waters. Pharmaceutical loading rates were calculated for each compound using the average in-stream concentration and volumetric flow rate. Adviser: Shannon Bartelt-Hun