Assessing the risk of exogenously consumed pharmaceuticals in land-applied human urine

Once separated, the use of urine as fertilizer is a particular attractive proposition and can significantly mitigate the release of nutrients and pharmaceutically active compounds (PhACs) to the environment. In the current study, a simple methodological framework is proposed for assessing risks that are posed by the land application of urine, which contains PhACs, in terms of 6 selected environmental and human-health endpoints. In total, 25 commonly used PhACs were conservatively assessed using the proposed methodology and results indicated that 14 of them may pose a risk with respect to either eco-toxicological or human-health endpoints. The receiving terrestrial environment was identified as the most susceptible of the eco-toxicological endpoints and hazard to human-health was most significant through food-chain transfer. The results highlight the need to consider the potential impacts associated with pharmaceuticals and the need to pre-treat urine to address the presence of problematic PhACs before it is applied on land.

Keywords: fertilizer, land application, pharmaceuticals, risk assessment, source separation, urine