Cytotoxic and phytotoxic effects of the main chemical components of spent pot-liner: A comparative approach

Abstract

Spent pot-liner (SPL) is a hazardous solid waste produced by the aluminum industry. Although its composition may vary, fluoride and cyanide salts as well as aluminum are predominant components. A seed-germination and root-elongation test was performed with Lactuca sativa seeds as a test system. SPL induced decrease of seed germination rate and root elongation. The concentration of 26.5g/L SPL was established from a regression curve as the IC50 (inhibition concentration 50%). Through chemical analyses, the concentrations of fluoride, cyanide and aluminum in SPL solutions of 26.5g/L (IC50), 39.75g/L (1.5IC50) and 13.25g/L (0.5IC50) were determined. Further, a cell-cycle test was conducted with root tips of L. sativa exposed to these same SPL solutions. All test chemicals presented toxic effects on meristematic cells of L. sativa. Aluminum was identified as the SPL component mainly responsible for reduction of the mitotic index. Chromosomal alterations resulted from the interactions among the three main chemical components of SPL, without a clear predominantly responsible agent. Induction of condensed nuclei was mainly due to effects of aluminum and fluoride, and may serve as an indicator of induced cell death.

Cytogenetic bioassays as tools to distinguish between toxic and non-toxic varieties of Jatropha curcas (Euphorbiaceae)

“…The statistical differences regarding the dynamics of germination and growth of roots exposed to physic nut oil was obtained after 48 hours of exposure, showing that, when present, the toxicity response is rapid. Moreover, the applied test requires little time, is simple and of low cost, which corroborates the perception of other authors on the use of macroscopic tests to investigate the toxic effects of any simple substance or chemical compound (Palmieri, Luber, Andrade, & Davide, 2014;Silveira, et al, 2017). Pinheiro et al, (2015) investigated the essential oil action of leaves of Plectranthus amboinicus, Carvacrol, and Thymol on lettuce, observing the toxic action of these compounds on seed development.…”

Assessment of phytotoxicity of leachates from landfilled waste and dust from foundry

“…This may indicate that the EC value of the leachate from the tested waste was primarily affected by sulfates. In contrast to chlorides and sulfates, fluorides are toxic to biota even at low concentrations (Stevens et al 2000;Palmieri et al 2014). Fluoride concentration was analyzed in the leachate, as it may be present in foundry waste.…”

“…There is a lack of information in the currently available literature concerning the effects of formaldehyde in aqueous solutions on seed germination and plant growth. In contrast, the influence of cyanide and phenol on plant germination is widely described (Hoekstra et al 2002;Yu and Gu 2007;Palmieri et al 2014). Hoekstra et al (2002) found that cyanides and amines are nitrogen phytotoxic compounds that decrease plant germination.…”

“…For this reason vascular plants are used for the phytoremediation of soils contaminated with cyanides (Yu and Gu 2007). Palmieri et al (2014) found that cyanides (0.0031 mg/L) may be less phytotoxic than fluorides (0.3938 mg/L) in elutes from solid waste from aluminum production (SPL-Spent pot-liner). In the current research, the cyanide content of LFW leachate was low compared to leachate from dust.…”

Antifungal, Antitumoral and Antioxidant Potential of the Danube Delta Nymphaea alba Extracts

“…Higher plants are suitable for toxicity studies, as they are recognized as excellent indicators of cytogenetic and mutagenic effects of chemicals. The germination tests are very simple, not very time consuming, and cheap, and could therefore be an ideal method for testing the toxicity of chemicals [34,35].…”