Cleaner production of salt-tolerance vegetable in coastal saline soils using reclaimed water irrigation: Observations from alleviated accumulation of endocrine disrupting chemicals and environmental burden

Abstract

It is important to investigate the feasibility of reclaimed water irrigation for fulfilling cleaner production of salt-tolerant vegetables in coastal saline soils which widely distribute in the world. Reclaimed water irrigation might cause the accumulation of endocrine disrupting chemicals in crops although it is a good approach for alleviating water resource shortage. This study firstly investigated the possible cleaner production and benefits of cultivating Mesembryanthemum crystallinum (M. crystallinum) in coastal saline soil irrigated by simulated reclaimed water. Concentrations of target pollutants including bisphenol A (BPA) and nonylphenol (NP) in root of M. crystallinum were higher than those in stem and leaf while soil salinity could increase the concentrations of BPA/NP in root and decrease those in leaf and stem. The highest concentration of BPA/NP in root of M. crystallinum growing in soil with salt content of 7.2‰ reached 29.28/243.47 μg/kg. BPA mainly accumulated in leaf of M. crystallinum with the highest amount of 621.93 ng under non-saline conditions while NP mainly accumulated in root with the highest amount of 1114.57 ng under saline conditions. The hazard quotients sharply decreased by >50% when the soil salinity increased from 1.1‰ to 7.2‰. Non-cancer health risks of BPA and NP in M. crystallinum were acceptable for all human groups while the daily intake of BPA/NP was much lower than the corresponding tolerant daily intake. Life cycle assessment illustrated that M. crystallinum cultivation in soil with salt content of 1.1‰ posed the lowest environmental burden. Salt-tolerant vegetables such as M. crystallinum would be recommended to be cultivated in low-salinity saline soils using reclaimed water irrigation due to lower pollutant accumulation and environmental burden to achieve the goals of cleaner vegetable production. These findings provide new insight on the promising potential of reclaimed water irrigation and crop cultivation in saline soils in coastal regions.