Prednicarbate

The ubiquity of pharmaceuticals and personal care products (PPCPs) and pesticides in aquatic environments has raised significant ecological concerns due to their potential to disrupt aquatic ecosystems. This study presents a high-throughput ultraperformance liquid chromatography-tandem mass spectrometry method without sample enrichment to monitor 323 PPCPs and pesticides in the surface water of the Jingmi Water Diversion Canal in Beijing, China. One hundred and three PPCPs and pesticides were detected, with the highest detection frequency observed for antibiotics, which constituted 25.2% of the total detections. Notably, the average concentrations of detected PPCPs and pesticides were significantly higher in the winter (69.0 ng/L) than in the summer (42.1 ng/L). Spatial characterization indicated higher concentrations of PPCPs and pesticides in urban areas compared with suburban areas, with carbendazim, caffeine, atrazine, and diazepam being the most frequently detected compounds. The ecological risk assessment based on risk quotient values identified moderate to high risks for aquatic organisms, particularly in urban areas and during winter. These findings highlight the necessity for improved wastewater treatment technologies and continuous environmental monitoring to protect aquatic ecosystems from the adverse effects of PPCPs and pesticides.

Abuse of glucocorticoid veterinary drugs in dairy industry can potentially threat milk safety and consequently influence human health. Here a reliable method for determination of 58 glucocorticoid drug residues in milk was established by combining solid phase extraction with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The analytes were extracted with acetonitrile and cleanup with EMR-Lipid lipid removal column. The analytes were chromatographically separated using Poroshell EC-C₁₈ column and acquired by electrospray ionization with multiple-reaction monitoring (MRM) mode. The limit of quantification (S/N ≥ 10) ranged from 0.2 to 2.0 µg/kg and the limit of detection (S/N ≥ 3) ranged from 0.1 to 1.0 µg/kg. Average recoveries were from 71% to 113%, the relative standard deviations (RSDs) were less than 15%, and the correlation coefficients (R²) of calibration curves exceeded 0.99. The method was applied to detect twenty milk products obtained from local supermarkets including ten pasteurized milk and ten UHT milk. Two endogenous glucocorticoids, i.e. hydrocortisone and cortisone were detected but not exceed the maximum residue limits (MRLs).