Utilization of artificial recharged effluent for irrigation: pollutants' removal and risk assessment

Abstract

The reclaimed water from soil aquifer treatment (SAT) column was reused for irrigation as the source water, pollutants' removal and health risk assessment was analyzed via the comparison with secondary and tertiary effluents. The effect of the SAT pre-treatment on the qualities and growth of different crops (Lachca sativa – lettuce, Brasica rapa var chinensis – pak choi, Cucumis sativus – cucumber, Brassica oleracea – cabbage, and Zea mays – maize) were evaluated. Experimental results demonstrated that the tertiary and SAT treatments had no significant effect on the crop qualities, and could efficiently decrease the accumulation of heavy metals (especially for SAT pre-treatment). Moreover, the carcinogenic risk of the chemical carcinogens for the 1.5 m SAT effluent irrigation declined roughly an order of magnitude as compared with the secondary effluent, and three to four orders of magnitude decreasing of the virus risk. These findings are significant for the safe and cheap reuse of secondary effluent for irrigation purposes.