Occurrence, distribution and risk assessment of antibiotics and pesticides in mariculture area around Liaodong Peninsula.

Mariculture stands as a pivotal enterprise aimed at enhancing the quality of human existence. However, the utilization of antibiotics and pesticides in the mariculture process poses threats to both the environment and human well-being. Therefore, it is of great significance to investigate the occurrence, distribution and risk of antibiotics and pesticides in mariculture areas. In this study, 11 kinds of antibiotics and 12 kinds of pesticides were screened in four mariculture areas around Liaodong Peninsula in China. The pollution characteristics of pollutants were investigated in three different mariculture stages. The pollution in the reproduction stage was the most serious, indicating that mariculture may have a potential impact on the surrounding seawater. Health risk assessment results indicate that the pollutants have a significant risk to human health, therefore it is necessary to strengthen the control of chemicals used in mariculture in future.

[Concentration Levels and Potential Ecological Risks of Current Use Pesticides in the Surface Seawater of Typical Liaoning Sea Areas].

Fourteen current-use pesticides (CUPs) in the surface seawaters of the typical Liaoning sea areas were analyzed using HPLC-MS/MS. The concentrations, distribution, and ecological risks were studied, as well as their source appointments using principal component analysis (PCA). The results revealed that seven types of CUPs were detected in the surface seawaters of the typical Liaoning sea areas. The total concentrations of these CUPs ranged from 16.7 ng·L-1 to 176.1 ng·L-1. The samples with high concentrations were collected mostly from the estuary, and the concentrations of CUPs in the western Liaodong Bay were generally higher than those in the northeastern Yellow Sea. Atrazine and triadimenol were the predominant CUPs, and their contribution rates accounted for 56.0% and 34.5%, respectively. The PCA results indicated that six types of CUPs might be caused by the runoff from farmlands and the wastewater discharge from the chemical pesticide factory, and fruit planting could be a substantial contributor to the single component acetochlor. Atrazine and acetochlor posed medium-high ecological risks to the microalgae, while all the seven types of CUPs showed relatively lower risks to invertebrates and fish.