Risk assessment and bioaccumulation of β-agonists in the Yellow River Delta of China: Implications for environmental...

Yellow River Delta is a critical area with the β-agonists residues, accumulation, migration and biomagnification. As a critical intensive aquaculture zone, the Yellow River Delta (YRD) requires comprehensive investigation of β-agonists pollution patterns. In this study, 12 β-agonists in different samples were tested. Fenoterol was the dominant residue in all samples, 7596.67 ng/kg in sediments, 3657.00 ng/kg in aquatic animals and 65.39 ng/L in water. -terol-type β-agonists exhibited potential bioaccumulation in crab, and notably, tulobuterol exhibited markedly high bioaccumulation in fish. Fenoterol and ractopamine exhibited low-level aquatic ecological risks. Based on the average consumption of aquatic animals, fenoterol exhibited moderate health risk, clenbuterol, brombuterol and formoterol exhibited low health risks. Based on the results of the bioaccumulation assessment and the two risk assessments, this investigation considered that Fenoterol and ractopamine are the prioritized β-agonists for future control. The concentrations of β-agonists in downstream areas were significantly lower than upstream areas (P < 0.05). Meanwhile, the concentrations of β-agonists in the core zones were significantly lower than experimental and buffer zones (P < 0.05). These results indicate the division of functional zones is effective in mitigate the β-agonists pollution. Based on the contamination status of β-agonists in various zones, this study recommends that: Maintain a minimum 2 km buffer between "core zones" and "experimental zones", maintain a minimum 40 km separation between core zones and human activity areas.