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Industrial activities are paramount to sustaining the economy in a rapidly developing nation and global powerhouse like India. Leather industries are important in the country's economic map due to the high revenue and employment generation opportunities. Several of these industries contribute largely to environmental pollution. The pollution of the environment is mainly caused by improper disposal of the tannery effluents that are highly rich in hexavalent chromium, a potent human carcinogen. Hexavalent chromium imparts toxic effects on the biotic components, which include plants, animals, and humans. The review portrays the current status of the Indian leather tanning sector and its impact on the Indian economy. The process of chromium tanning and its adverse effects on the environmental biotic components have been briefly discussed. Phytoremediation of these effluents using suitable hyperaccumulating plants has been suggested as an eco-friendly and cost-effective approach for the sustainable restoration of the polluted environment. The mechanism behind the remediation approach and the factors influencing it have been detailed. The manuscript briefly discusses some important advancements in the field of phytoremediation and emerging technologies and concludes by emphasizing further research for sustainable management of tannery wastes., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

In the recent years, Uttarakhand has emerged as one of the most attractive industrial destinations in India. The industrial sector of the Uttarakhand state is growing day-byday, and the industrial effluents, disposed by the industries, cause environmental pollution. The industrial effluents have many pollutants, including heavy metals. The major environmental problem is the pollution of heavy metals, and they cause serious diseases in animals, including human. In the present study, the streptomyces strain isolated from sludge contaminated with heavy metal was trained for heavy metal remediation and used for bioremediation activity for chromium, copper and lead in the waste. The metal chromium reduction ranged from 0.386 to 6.42 mg/L, which showed maximum reduction in chromium by Streptomyces sp., copper reduction ranged from 0.288 to 1.129 mg/L, and reduction in lead ranged from 0.063 to 0.286 mg/L. In future, the gram positive filamentous streptomyces strain can be used for chromium ion reduction as bioremediating agent. [ABSTRACT FROM AUTHOR]

Using algae to treat industrial effluents containing heavy metals presents an alternative to the current practice of using other biosorbents and physical and chemical methods. In this study, effluent from a leather-processing chemical industry in Ranipet, Tamil Nadu, India, was treated for the removal of heavy metals using the microalga, Chlorella vulgaris, which was isolated from the effluent itself. The objectives of this study were to (I) assess the mass balance of a model parameter, lead, in laboratory conditions and estimate the lead adsorption capabilities of the microalga and (2) conduct pilot-scale studies for the removal of heavy metals, using the microalga, from the effluent and the solid waste accumulated over the years generated by conventional treatment methods. The results of the study show that after 8 hours, Chiorella vulgaris exhibited a better adsorption capacity under sunlight compared to laboratory conditions (i.e., 30.6 mg/g dry weight vs 10.5 mg/g dry weight, respectively). Similarly, reduction of heavy metals and mass balance in pilot-scale field studies conducted in a high-rate algal pond showed that the microalga, apart from adsorption, complexation, and entrapment mechanisms, is likely to possess phycovolatilization capability probably via biotransformation processes. [ABSTRACT FROM AUTHOR]

Phycoremediation is the use of algae for the removal or biotransformation of pollutants from wastewater. Employing this technology in the treatment of industrial effluents presents an alternative to the current practice of using conventional methods, including physical and chemical methods. In the present study, the effluent from a leather-processing chemical manufacturing facility, situated at Ranipet, Tamil Nadu, India, was treated using the microalga, Chlorella vulgaris, which was isolated from the effluent itself. The objective of this study was to treat the effluent as well as ETP (effluent treatment plant) solid waste by phycoremediation (pilot-scale field study as well as laboratory study) and to analyse the physico-chemical parameters before and after treatment. The results obtained showed that Chlorella vulgaris exhibited appreciable nutrient scavenging properties under both laboratory and field conditions, although phycoremediation carried out in sunlight (field study) gave better results. Moreover, the growth of Chlorella vulgaris was faster under field conditions. [ABSTRACT FROM AUTHOR]

Abstract: The evaluation and assessment of monitoring data generated over a period of 1983–2007 (25 years) of a nuclear facility is presented. Time trends of particulate radioactivity, correlation between 137Cs in discharge canal seawater and station discharged activity and correlation of 137Cs, 60Co, and 131I in marine species such as sponge and Nerita (gastropod) and corresponding discharged activity are discussed. The concentration of 137Cs and 131I in seawater versus biota are discussed. A good correlation between 137Cs in seawater and 137Cs in liquid waste discharged was observed (R 2 = 0.8, p < 0.001). Similarly, correlation was good for Nerita and discharged concentration of 137Cs, 131I and 60Co (R 2 = 0.55–0.73 and p < 0.001). The measurements over the years indicated that there is no accumulation of radionuclides in either the terrestrial or aquatic environments. The mean 137Cs decreased from the pre-operational levels: 7.0–3.6 Bq kg−1 in soil, 0.91–0.016 Bq L−1 in milk and 0.28–0.036 Bq kg−1 in vegetation. Similarly, the mean 90Sr in these matrixes decreased from 3.9 to 0.26 Bq kg−1; 0.37–0.011 Bq L−1 and 0.34–0.022 Bq kg−1 respectively. Cesium-137 of about 700 μBq m−3 was measured in the air filter disks during 1986 and there was a decrease of three orders of magnitude in concentration over the 25 years. The evaluation of environmental data indicated that the radionuclide concentrations and potential impacts, in terms of effective dose to the members of public, have significantly reduced since 1969. [Copyright &y& Elsevier]

Very high levels of a range of pharmaceuticals have been reported recently in the effluent from a wastewater treatment plant near Hyderabad, India. The plant serves approximately 90 manufacturers of bulk drugs that primarily are exported to the world market. Fluoroquinolone antibiotics were found at levels that are highly toxic to various microorganisms. Even though milligram-perliter levels of drugs targeting human proteins also have been found, it is difficult to conclude whether these levels are sufficiently high to adversely affect fish or amphibians due to the lack of relevant chronic toxicity data for most human pharmaceuticals. To assess potential effects on aquatic vertebrates, tadpoles of Xenopus tropicalis were exposed to three dilutions of effluent (0.2, 0.6, and 2%) over 14 d, starting at developmental stage 51. Additionally, newly fertilized zebrafish (Danio rerio) were exposed to diluted effluent in 96-well plates for up to 144 h postfertilization (hpf). The tadpoles' body lengths, weights, and developmental stages were recorded, whereas a larger number of sublethal and lethal endpoints were studied in the zebrafish. A 40% reduced growth of the exposed tadpoles was demonstrated at the lowest tested effluent concentration (0.2%), indicating potent constituents in the effluent that can adversely affect aquatic vertebrates. The median lethal concentration (LC50) for zebrafish at 144 hpf was between 2.7 and 8.1% in different experiments. Reduced spontaneous movements, pigmentation, and heart rate were recorded within 48 hpf at 8 and 16% effluent concentrations. Treated effluent from a plant that serves as an important link in the global supply chain for bulk drugs is thus shown to cause adverse effects to aquatic vertebrates even at very high dilutions. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the effect of biocompost from sugarcane distillery effluent on metribuzin degradation and mobility in a sandy loam soil in Northern India. The soil used has come from the experimental farm of the Indian Agricultural Research Institute. The biocompost was gathered from Simbhaoli Sugar Mill Ltd. and the physicochemical characteristics of the biocompost included a pH of 7.6 and an organic carbon (OC) content of 31.0%. The study indicates that metribuzin was more persistent in biocompost-unamended flooded soil than in non-flooded soil. The study also shows that biocompost from sugarcane distillery effluent can be used effectively to lessen downward mobility of metribuzin in low-organic-matter sandy loam soil.

Effluents originating from pesticides, agro-chemicals, textile dyes and dyestuffs industries are always associated with high turbidity, colour, nutrient load, and heavy metals, toxic and persistent compounds. But even with such an anthropogenic nature, these effluents contain dynamic cyanobacterial communities. Documentation of cyanobacterial cultures along the water channels of effluents discharged by above mentioned industries along the west coast of India and their relationship with water quality is reported in this study. Intensity of pollution was evaluated by physico-chemical analysis of water. Higher load of solids, carbon and nutrients were found to be persistent throughout the analysis. Sediment and water samples were found to be colored in nature. Cyanobacterial community structure was found to be influenced by the anthropogenic pollution. 40 different cyanobacterial species were recorded from 14 genera of 5 families and an elevated occurrence of Phormidium, Oscillatoria and Chroococcus genera was observed in all the sampling sites. [ABSTRACT FROM AUTHOR]

Abstract: An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples—raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal—Na, K, Ca, Mg, and minor elements in coal—Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing. [Copyright &y& Elsevier]

Hospital effluent with its high content of multidrug resistant (MDR) enterobacteria and the presence of enteric pathogens could pose a grave problem for the community. It was planned at our tertiary care hospital in central India to study the population changes at various steps of effluent treatment plant (ETP) like collection, aeration, clarification, liquid sludge, dried sludge, high-pressure filter and treated wastewater. The study included viable bacterial counts, coliform counts, staphylococcal, enterococcal, Pseudomonas and multiple drug resistant (MDR) gram negative bacterial counts in the different stages of ETP. In order to study the distribution of bacteria as free floating in liquid and adherent to suspended particles, enumeration of the bacteria in the filterate and the sediment was also carried out. The effluent input showed 55% of the 8.6×106/ml bacteria as coliforms and E. coli which was a typical of fecal flora. The prevalence of MDR coliforms was 0.26%. The substantial reduction (>3 log) was seen for the effluent coming from the clarifier. The bulk of the bacteria in the hospital effluent remains firmly adhered to solid particles; aeration and clarification removes bulk of the bacteria by physical processes like flocculation. The treated liquid effluent still contains sizeable loads of MDR bacteria and inactivation by procedure such as chlorination is required. The bacteria get concentrated in sludge and a greater concentration of chlorine is required for decontamination. [Copyright &y& Elsevier]

Water resources such as rivers and oceans an indispensable resource for the living. The present investigation was carried out for biodegradation of industrial effluent by using bacterial isolates immobilized in PDMS sponges. Bacterial isolates DP4 Bacillus and DP7 Stenotrophomonas (black cotton soil of Maharashtra, India) was performed to degrade the industrial spentwash. In first experiment, effluent was added to the nutrient broth (NB) inoculated with DP4 and DP7 strains in different flasks containing PDMS sponges. DP4 strain degraded 84% of melanoidin as compared to DP7 strain, which degraded 50% melanoidin in 6 days. In second experiment, both bacterial strains were inoculated in (i) NB media (ii) immobilized in PDMS sponges, inoculated in NB media and the effluent was added. Degradation of melanoidin was determined at intervals of 24h using spectrophotometer (OD 520nm). Immobilized cells degraded melanoidin better than free cells and Bacillus DP4 showed a higher degradation rate as compared to Stenotrophomonas DP7. • Immobilized bacterial isolates were used to degrade melanoidins from spent wash. • Biodegradation efficiency of free and immobilized cells were compared. • Melanoidin degradation was improved using 'repeated addition' strategy. [ABSTRACT FROM AUTHOR]

In this communication, the results of seed germination inhibitory activity of pulp and paper mill effluent of Faizabad has been evaluated on the basis of experiments conducted under standard laboratory conditions during the year 2005-2006 in the Botany Department of K. S. Saket PG) College, Ayodhya, Faizabad (U.P.), India. [ABSTRACT FROM AUTHOR]