Oral Presentation SETAC Asia-Pacific Virtual Conference 2022

In-situ application of the diffusive gradients in thin films technique in aquaculture ponds for monitoring antibiotics, hormones and herbicides (#39)

Yiqin Chen 1 , Juan-Ying Li 1
  1. Shanghai Ocean University, Pudong New Area, SHANGHAI, China

Driven by the huge demand for high-quality protein internationally, aquaculture production has surpassed wild fishing since the 1990s and kept dramatic growth in China ever since. In recent years, as the abuse of antibiotics, hormones and herbicides has worsened in aquaculture industry, it is important to monitor the concentrations of those  contaminants in aquaculture water more effortlessly (Li et al., 2021). The aim of this study was to develop a reliable sampling method for chemical monitoring in aquaculture ponds based on the technique of diffusive gradients in thin films (DGT). A binding material (XDA-1 resin) with high adsorption capacity for antibiotics, hormones and herbicides was selected. In laboratory, the diffusion coefficients of 11 antibiotics, 3 hormones and 3 herbicides of the XDA-1-DGT devices were tested and ranged from 1.0×10−6 to 8.7×10−5 cm2/s. During the in-situ application of XDA-1-DGT devices in different aquaculture ponds, concentrations of 11 antibiotics, 3 hormones and 3 herbicides in aquaculture water (CSOLN) via grab sampling were also analyzed and found ranging from 0.03- 6.3 ng/L, lower than the results based on DGT (CDGT) (1.2- 1.3×102 ng/L). The values of CDGT/CSOLN were larger than one unit, suggesting that the rates of resupply of target chemicals (antibiotics, hormones and herbicides) by the desorption and diffusion of pond water were higher than the rates of uptake by XDA-1-DGT, and pond water was proved a sufficient reservoir of antibiotics for DGT application. The value of Log (CDGT/CSOLN) of 1.1 derived from the application in the aquaculture ponds of 14 regions in Eastern China can be a reference value for future chemical monitoring based on DGT technique. And the accuracy of this value was found hardly affected by the physical and chemical properties of chemicals with PKa ranging from -1-12, Log Kow ranging from 0-4.5 and Log solubility ranging from 0.0-4.0.

  1. Li, J.Y., Wen, J., Chen, Y.Q., Wang, Q., Yin, J., 2021. Antibiotics in cultured freshwater products in Eastern China: Occurrence, human health risks, sources, and bioaccumulation potential. Chemosphere. 264:128441