Meta-Analysis of the Distribution of Pharmaceuticals and Personal Care Products in Natural Streams of United States and Its Correlations with Anthropogenic Factors

Pharmaceuticals and personal care products (PPCPs) are ubiquitous in natural environments. Due to their inherent relationships with human activities, we hypothesized that factors relating to anthropogenic activities could be useful in predicting the extent of PPCP pollution in natural waterways. A meta-analysis was performed on reported PPCP concentrations in streams across the United States from 2000 to 2022. Existing US census and land cover data were then collected and analyzed for their potential correlations with the PPCP distribution. Studies of 163 sampling sites reported a total of 109 unique PPCPs, with individual concentrations ranging from 0.0019 to 79.5 μg/L. A total of 37 PPCPs were detected in all three land use types (developed, forested, and agricultural). These common PPCPs had varying correlations with anthropogenic factors, i.e., population size, demographic distribution, or income. Cholesterol and coprostanol varied significantly in concentration between different types of land use, despite a lack of correlation with population size. However, caffeine and 1,7-dimethylxanthine interacted with both the population size and land use. Our results allow a greater insight into the prevalence of PPCPs in the environment and the need to account for many variables to predict the environmental concentrations of these pollutants.