The Physiological and Biochemical Responses of Daphnia magna to Dewatered Drinking Water Treatment Residue

Abstract

There have been widespread attempts to recycle drinking water treatment residue (DWTR) after dewatering for environmental remediation, which is beneficial for both the environment and the economy. The directly discharged DWTR without dewatering to natural water bodies, however, was reported to show signs of chronic toxicity to Daphnia magna (D. magna), a typical zooplankton in the aquatic environment. This study comprehensively assessed the effect of dewatered DWTR on the physiological and biochemical characteristics of D. magna based on acute and chronic toxicity tests. The results showed that the survival, growth, reproduction, body morphology of offspring, and the antioxidant enzymes of D. magna were not affected by the dewatered DWTR. These physiological and biochemical indexes also had no undesirable changes for the DWTR-amended sediments (with ratios of 0–50%) incubated for 10 and 180 d; the growth and reproduction were even promoted when D. magna was exposed to 5000 mg-sediment L−1, which may be due to the extra nutrients supplied by the amended sediments for the animals. The results demonstrated that by contrast with the directly discharged DWTR without dewatering, the dewatered DWTR could be safe to D. magna. Further analysis suggested that heavy metals (Pb, Ni, Cu, Cr, and Zn) with relatively low concentrations and high stability could be the main reasons leading to the high safety of the dewatered DWTR. Overall, dewatered DWTR can be considered a non-hazardous material for zooplankton.

Evaluation of Toxicity of Crude Phlorotannins and Phloroglucinol Using Different Model Organisms

“…Adult D. magna were reared to produce neonates. After 24 h, neonates were collected and used in the study [ 71 , 72 , 73 ].…”

Washing and Heat Treatment of Aluminum-Based Drinking Water Treatment Residuals to Optimize Phosphorus Sorption and Nitrogen Leaching: Considerations for Lake Restoration

“…Chronic and/or high-concentration exposure to fresh sedimentation sludge has been shown to have harmful effects on the Daphnia genus, which is used as an indicator organism [78,79]. However, ecological and human health risk assessments have shown limited risks [80,81], especially when de-watering or treatment was completed before use of DWTR in environmental application [82]. Again, oxygen-limited heat treatment may be the most reliably safe choice for treatment.…”

Evaluation of the Effect of Gold Mining on the Water Quality in Monterrey, Bolívar (Colombia)

“…Studies conducted by Forget et al [53] with D. magna, show percentages of toxicity up to 70% against heavy metals. Castro-Català et al [54] evaluated the toxicity of sediments and water in rivers with the presence of pesticides and heavy metals using D. magna as an animal indicator, showing that it can be sensitive to these types of samples, due to its high metabolic rate [55]. Likewise, Lattuada et al [56], in southern Brazil, used D. magna as an indicator of toxicity in waters affected by coal mining, in which heavy metals such as Fe, Mn, Zn, Ni, Cd, and Pb were found.…”