Heavy metals, especially Pb (lead), are generally toxic to living things. Pb can contaminate organisms in the water through the food chain. The purpose of this study is to enhance water quality by using Salvinia molesta to phytoremediate Pb-polluted water. This study aims to evaluate the ability of S. molesta as a Pb phytoremediator. We evaluated total protein, free amino acids produced by the plant, and plant growth (dry biomass). S. molesta was grown in a hydroponic system exposed to Pb at dosages of 0, 5, 10, and 15 ppm for 7 and 14 days. Pb level was analyzed using Atomic Absorption Spectrophotometer and amino acids were analyzed using High-Pressure Liquid Chromatography. Data were statistically analyzed using analysis of variance (ANOVA) followed by Tukey’s test (α < 0.05). Results showed a significant change in Pb content in the roots and leaves of Pb-exposed S. molesta Mitch compared to control. In Pb-exposed plants, total protein and amino acids, especially cysteine, were lowered. S. molesta could be used as a Pb phytoremediator due to its high potential to survive Pb exposure and its ability to absorb Pb.

This research was conducted in the waters of Malili River, East Luwu Regency, with 4 observation points in Malili River East Luwu Regency, namely: (a) Southeast Sulawesi Sub Das (Point 1) namely Pongkeru village bridge, Coordinate point 12126.69’8°” E; (b) Larona Sub Das Karebbe basin bridge (Point 2), Coordinate point 12115.09’9°” E; (c) The meeting point of Larona sub-dash and Pongkeru sub-dash (Point 3), coordinate point 12159.64’8°” E; (d) Upper Malili River, Malili village, Malili bridge (Point 4), Coordinate point 12147.20’5°” E. Metal concentration and distribution were analyzed descriptively with the help of images (maps), graphs, and tables. Differences in Pb, Cd, and Hg metal concentrations in sediments between point locations were tested using analysis of variance (ANOVA) through the SPSS version 22 program. The relation between grain size, organic matter, and Pb, Cd, and Hg metal concentrations was tested using linear correlation. The results showed that the sediment content of Pb and Cd metal concentrations at each point location did not exceed NOAA (1999) quality standards. In the sediment, Hg metal concentration exceeds the quality standards of NOAA (1999) at each point, namely point 1. Pongkeru 0.590 μg.g-1, point 2. Karebbe 0.229 μg.g-1, point 3. Kawasule 0.514 μg.g-1 and point 4. Malili 0.358 μg.g-1. The relation between sediment size and Pb, Cd, and Hg metal concentrations at each point location has a weak correlation. The relation does not significantly affect the content of heavy metals in the sediment. It may be due to other factors, such as the source of heavy metal pollutants in each different point location. The relation between organic matter and the concentration of Pb, Cd, and Hg metals at each point location has a weak correlation. The relation does not significantly affect the content of heavy metals in the sediment because it may be due to other factors, such as different sources of heavy metal pollutants in each point location.