Toxicity and removal of Direct Red 28 diazo dye in living polymeric systems

Abstract

Aquatic environments are often contaminated with various compounds, with potential toxicity towards aquatic organisms, which may enter the food chain. Azo dyes are used in various industries and contamination of waters has been reported. The present paper assesses the toxicity of the synthetic, water soluble Congo Red dye towards Lemna minor from a physiological and cytogenetical point of view. The dye was tested in 5-5000 ppm concentrations. Total frond surface, root growth and fresh mass reductions were registered from 5 ppm dye concentration, with a concentration-dependent response and calculated EC50 of 1530 ppm. Plant growth was completely inhibited above 2500 ppm. Dye accumulation was observed in tissues, along with necrosis formation. Chlorophyll a contents decreased, while carotenoid contents increased above 2500 ppm. Significant inhibition of PSII efficiency was recorded above 1000 ppm. Mitotic indices were decreased at 5 and 1000 ppm dye and were 0 at 5000 ppm. The number of chromosomal aberrations significantly increased at 5 and 1000 ppm dye. The growth medium was decontaminated up to 56% at 250 ppm dye concentration by Lemna plants. Congo Red azo dye presented toxicity towards Lemna minor, from a physiological and cyotgenetical point of view, especially at higher concentrations. In the same time, a phytoremediation potential of duckweed with respect to the tested dye was demonstrated.

Stability of Selected Hydrogen Bonded Semiconductors in Organic Electronic Devices

“…Hellophytes (Phragmites australis, Alternanthera philoxeroides, Typha domingensis, Junus sp. ), ornamental plants (Ipomoea hederifolia, Aster amellus, Portulaca grandiflora, Zinnia angustifolia, Petunia grandiflora, Glandularia pulchella) and many ferns and herbs have been extensively used for dye removal. ,, Recently, aquatic plants such as Pistia stratiotes or Lemna minor have been used successfully in the elimination of carcinogenic azo red dye, although plants cannot be reused and at high concentrations suffer irreversible damage. , Some of these plants have been used in phytoreactors and constructed wetlands, obtaining interesting results in biotransformation, although the derived products were not always non/less toxic than untreated compounds. , Plant tissue cultures can be an alternative for the degradation of these compounds. They offer advantages like they lack chlorophyll and other plant pigments, reproducibility, homogeneity of the plant material, reduced problems of uptake and transport, easy manipulation and more quick results.…”

“…164,165 Some of these plants have been used in phytoreactors and constructed wetlands, obtaining interesting results in biotransformation, although the derived products were not always non/less toxic than untreated compounds. 159,166 Plant tissue cultures can be an alternative for the degradation of these compounds. They offer advantages like they lack chlorophyll and other plant pigments, reproducibility, homogeneity of the plant material, reduced problems of uptake and transport, easy manipulation and more quick results.…”

Bioefficacies of microbes for mitigation of Azo dyes in textile industry effluent: A review

“…A similar study was conducted by Lade et al (2015) on the degraded metabolites of dye RB172 through acute and phytotoxicity, and the same findings were reported. Lobiuc et al (2018) assessed CR toxicity towards Lemna minor and reported reduction in root growth, total frond surface and fresh mass reduced from 5 ppm dye concentration, whereas above 2500 ppm concentration, complete plant growth was inhibited. Khandare et al (2013) demonstrated the metabolism fate of Direct Red 5B by P. grandiflora, P. putida, and their consortium with the help of GC-MS analysis.…”

The Influence of Temperature on the Absorption Capacity of Total Phosphorus by Lemna minor L.

“…Most of those wastewaters have been evacuated into lakes and rivers, leading to eutrophication of aquatic systems [12]. Anthropogenic activities, especially chemical pollution, have triggered various forms of environmental change [13]. According to the OECD (World Economic Cooperation and Development Organization), 80% of water eutrophication has been attributed to phosphorus, 10% of water bodies eutrophication directly related to nitrogen and phosphorus and the remaining 10% has been triggered by nitrogen and other factors [14].…”