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Aquatic plants play effective in removing heavy metal (HM) as a prominent factor of bioremediations, however, there are still knowledge gaps in species selection and configuration for high removal efficiency (RE) of compound HM and ornamental value. In this study, seven emergent-aquatic-plant species were configured into seven groups and planted in a simulated swine wastewater (SW) with Cu, Zn, and Cd for 75 days in summer. REs of Cu, Zn, and Cd were 45.06–86.93%, 42.40–87.22%, and 73.85–85.52% at day 75, respectively. Higher REs were observed from day 30–45 for Cu and Zn, whereas days 15–30 for Cd. The synergistic removal of Zn and Cu or Zn and Cd was almost observed (p < 0.05). The configuration of G5 (S. tabernaemontani , I. sibirica , and P. cordata) was generally efficient roles in the removal at day 45, with REs of 85.14%, 87.06%, and 83.56% for Cu, Zn, and Cd, respectively. The dry weight of roots, water NH 4 +-N, temperature, pH, and dissolved oxygen acted on heavy-metal removal. During days 45–75, concentrations of Cu, Zn, and Cd in G5 were 0.52–0.66, 0.54–0.65, and 0.23–0.33 mg L−1. The former two were below the limits of Grade Ⅱ (1.0 mg L−1) and the latter was above the limits of Grade Ⅴ (0.1 mg L−1; GB3838-2002). Thus, G5 could be optimal for Cu and Zn removal from simulated SW, however, efficient Cd removal is required to ensure efficient SW recycling. • Compound HMs almost exist in SW, restrict SW reuse, and threaten human health. • REs of compound HMs were estimated and assessed under seven EAP groups. • The optimal configuration was the group of S. tabernaemontani , I. sibirica , and P. cordata. • Selected EAP configuration was proposed to plant about 45 days in summer. • Further steps should be taken for Cd removal with EAPs for SW recycles. [ABSTRACT FROM AUTHOR]

The co-processing of secondary wastes during ordinary Portland cement (OPC) can result in high heavy metal concentrations in OPC products. However, earlier studies have not evaluated the concentrations of heavy metals (HMs) in OPC as a function of secondary input materials. Further, the health risk assessment (HRA) model has, thus far, has not been employed to assess the potential health risks associated with secondary raw materials and secondary fuels in OPC. Hence, to address these knowledge gaps, herein, monthly data for six HMs in the input materials and fuels from seven OPC manufacturers in the Republic of Korea were analyzed and modeled. Pb and Cu concentrations were found to be approximately 10–200 and 4–200 times higher than those of the other HMs, respectively. Furthermore, maximum Pb and Cu concentrations were 2–3 and 2–5 times higher than those reported in other countries, respectively. The quantity of input material had a significant influence on the observed patterns, and secondary raw materials, secondary additives, and secondary fuels were also determined to be important. Based on HRA assessment, although the risk levels were within permissible ranges, carcinogenic hazards attributable to Cr and Pb were not negligible. The results can aid in informed decision making and in implementing effective measures for managing risks associated with HMs in the OPC industry, thereby ameliorating threats to human health and environment. • Co-processing approach can result in the heavy metal contamination of cement products. • Heavy metal concentrations depended on the type and quantity of the input material. • Secondary materials were a more prominent source of heavy metals compared to primary. • Health risks due to Cr and Pb were not negligible. [ABSTRACT FROM AUTHOR]