Differential accumulation of clenbuterol hydrochloride in vegetables under hydroponic exposure: Physiological responses and health risk analysis.

Clenbuterol hydrochloride (CB), an illicit feed additive, has been detected in the environment and may contaminate edible vegetables, posing potential health risks to humans. This study investigated the impacts of CB exposure on the growth, physiology, and health risk of four vegetables (Brassica napus, Lactuca sativa, Spinacia oleracea, and Daucus carota) using hydroponic experiments. CB exposure inhibited vegetable growth and photosynthetic activities. Under short-term exposure, high CB concentrations significantly reduced dry weight, while prolonged exposure partially mitigated these inhibitory effects in rapeseed and lettuce. Among the tested species, carrots exhibited the highest CB, while lettuce showed stronger tolerance to CB stress. CB exposure disrupted mineral nutrient homeostasis, particularly altering Fe, Ca, and Mg uptake in a tissue- and species-dependent manner. Linear regression analysis revealed that CB-induced reduction in chlorophyll content was the main factor contributing to the decreased biomass. Moreover, CB stress induced oxidative damage and nitrogen metabolism imbalance, as evidenced by elevated malondialdehyde content, impaired antioxidant enzyme activity, and enhanced cell apoptosis. Both exposure duration and CB concentration influenced target hazard quotient (THQ) values, with prolonged high-dose exposure posing considerable health risks. These findings provide critical insights into the ecotoxicological effects of CB on vegetables crops and highlight the need for effective management of CB contamination and associated human health risks.