Assessing the presence of pharmaceuticals in soil and plants irrigated with treated wastewater in Oman

Purpose: This study conducted to assess the presence of pharmaceuticals in soils and crops irrigated with treated wastewater in Oman. The study was aimed to evaluate the potential of plant uptake of four commonly used pharmaceuticals in Oman: amoxicillin, sulfamethoxazole, trimethoprim and ibuprofen by radish (Raphanus raphanistrum subsp. sativius) in soil culture. Methods: Radish (Raphanus raphanistrum) was selected as a test crop. Liquid chromatography mass spectrometry/mass spectrometry (LC–MS/MS) instrument was used to measure concentrations of pharmaceuticals. Groundwater and treated wastewater were used for irrigation. Additionally, there were two spiked treatments; high-spiked concentration (5 mg/l) and low-spiked concentration (1 mg/l). Results: Results of the study showed that trimethoprim and ibuprofen were not detected in any samples of soil and plant. Sulfamethoxazole accumulated in radish roots for low- and high-spiked treatments. Amoxicillin accumulated in roots with low-spiked- as well as high-spiked treatments. Radish showed the ability to translocate some of the selected pharmaceuticals from soil irrigated with treated wastewater if they are present in sufficient concentrations. Conclusions: Radish showed positive uptake of some selected pharmaceuticals from soil irrigated with treated wastewater with spiked (both high and low) concentration of pharmaceuticals and has the ability to accumulate them in the roots. Pharmaceutical usage and disposal must be given attention to prevent their occurrences in the environment. Furthermore, treated wastewater must be given attention, as it is an important source of water in Oman, which suffers from water shortages.