A Real-Time Investigation on Public Health Consequences of Chromium Laden Effluent from the Leather Industries

Background: Extensive evidence of elevated chromium (Cr) in the surface and groundwater exists. However, the importance of exposure toward Cr?associated health risks in areas with tanneries is still often neglected. These situations prompted an independent research study to investigate the views of those close?knit communities who are being directly affected by this tannery village. Objectives: To establish an understanding of the local demographics and; exploratory data analysis (EDA) to discover patterns in the occurrence of diseases; measure the awareness of residents of the presence of Cr and its harmful health effects. Methods: The EDA technique was used to conduct survey studies on data to uncover patterns, identify anomalies, test hypotheses, and validate assumptions using summary statistics and graphical representations. Results: Out of 14 diseases directly linked to high Cr toxicity, the study reported high levels of diarrhea, epigastric pain, and moderate?to?severe cases of vertigo among those aged more than 22 years. With over 90 active tanneries and toxic Cr released to the environment in a town of <78 km2 area (1.2 tannery/km), there are only 15 hospitals (0.2 hospitals/km) for the population currently accommodating more than a quarter?million people daily (3205 people/km). Conclusion: New mitigation strategies must be put forth to alleviate the negative impacts of the tanneries on the residents and nature most affected as well as the population as a whole.

Seguridad ocupacional contra Bacillus anthracis en la industria de curtiembre peruana / Occupational safety against Bacillus anthracis in the Peruvian tannery industry

El carbunco es una zoonosis que afecta a animales herbívoros, causada por el microorganismo Bacillus anthracis; que se encuentra en su forma vegetativa en el organismo infectado, y una vez en contacto con el aire forma esporas que infectan al huésped, liberando toxinas que inducen edema, septicemia y necrosis tisular. En humanos, la transmisión se produce por cortes, pinchazos o contacto directo de piel lesionada con esporas o tejidos de animales infectados. En Perú, para la década de 1980, se reportaron 400 casos anuales en áreas rurales agrícolas, adquiridos por manipulación del ganado vacuno, muerto por ántrax. Es por ello, que la piel y el cuero procedente de animales infectados representa un riesgo de infección para los trabajadores de industrias curtiembres. Se realizó un estudio transversal para evaluar el riesgo biológico ocupacional y las medidas de bioseguridad relacionadas con el Bacillus anthracis en pequeñas, medianas y grandes empresas curtiembres peruanas. Se aplicó un instrumento a los trabajadores para cuantificar las variables, componentes de riesgo biológico y conocer las medidas higiénicas adoptadas. Posteriormente se calculó e interpretó el nivel de riesgo biológico. Se encontró que el nivel de riesgo supera el límite de exposición biológica para el Bacillus anthracis en todas las empresas evaluadas y los trabajadores de las pequeñas empresas tienen poco conocimiento acerca del riesgo biológico al que están expuestos, siendo necesaria la capacitación de los trabajadores acerca del Bacillus anthracis y adopción de medidas de bioseguridad en empresas curtiembres, que garanticen la salud de los trabajadores(AU)

Anthrax is a zoonosis that affects herbivorous animals, caused by the microorganism Bacillus anthracis; which is found in its vegetative form in the infected organism, and once in contact with the air it forms spores that infect the host, releasing toxins that induce edema, septicemia and tissue necrosis. In humans, transmission occurs through cuts, punctures, or direct contact of broken skin with spores or tissues of infected animals. In Peru, for the 1980s, 400 annual cases were reported in rural agricultural areas, acquired by handling cattle, which died of anthrax. For this reason, the skin and leather from infected animals represent a risk of infection for workers in tanneries. A cross-sectional study was carried out to evaluate the occupational biological risk and biosafety measures related to Bacillus anthracis in small, medium and large Peruvian tanneries. An instrument was applied to the workers to quantify the variables, components of biological risk and to know the hygienic measures adopted. Subsequently, the level of biological risk was calculated and interpreted. It was found that the level of risk exceeds the biological exposure limit for Bacillus anthracis in all the companies evaluated and the workers of the small companies have little knowledge about the biological risk to which they are exposed, being necessary the training of the workers about the Bacillus anthracis and adoption of biosafety measures in tanneries, which guarantee the health of workers(AU)

Loofah immobilized with Cladosporium cladosporioides CEL14 is a potential bioremediating agent for hexavalent chromium in tannery wastewater

Aims@#Chromium salt possesses unique characteristics that render it useful in numerous applications in several industrial processes, especially tanning of animal hides which act as a major source of hexavalent chromium toxicity in environment. This study aimed to evaluate the efficiency of loofah immobilized Cladosporium cladosporioides CEL14 in remediate tannery wastewater which contains hexavalent chromium. @*Methodology and results@#A total of 18 fungal species were isolated from three different sites of tannery wastewater in Egypt, of which C. cladosporioides CEL14 was the most capable species of chromate remediation with 81% after 7 days of incubation as free cells. The experiments were conducted in minimum salt medium supplemented with 200 ppm chromate in the form of potassium dichromate. Different process parameters studies demonstrated that chromate was completely removed at 30 °C, pH 6, 0.1% malt extract and 0.2% glucose after 7 days of incubation with 20% inoculum size. After that, C. cladosporioides was immobilized on a natural support material (loofah). The removal ability of chromate was enhanced through permanent viable immobilization on loofah pieces, which showing complete removal of chromate within 3 days. The toxicity assessment of treated tannery effluents revealed that 74% of Brassica napus seeds were germinated upon exposure to the treated effluent.@*Conclusion, significance and impact of study@#This study revealed that C. cladosporioides CEL14 isolate has high potential as bioremediating agent against toxic hexavalent chromium. The removal ability of toxic chromate was enhanced through permanent viable immobilization on loofah pieces. This technology is simple, cost effective, efficient and environmentally friendly. The loofah immobilized with C. cladosporioides CEL14 has potential to be applied in wastewater treatment of small-scale tanneries after onsite trials.

Effectiveness of application of lignolytic fungal strains, Cladosporium uredinicola GRDBF21 and Bipolaris maydis GRDBF23 in the treatment of tannery effluent

Aim: This study aims to investigate the ability of laccase producing fungal strains Cladosporium uredinicola GRDBF21 and Bipolaris maydis GRDBF23 isolated from decaying wood bark in decolouration and detoxification of tannery effluent. Methodology: Fungal strains from decaying wood bark samples were isolated by serial dilution technique followed by single spore isolation method. The selected fungal isolates were investigated for their laccase enzyme production. Their effect on physio-chemical properties of tannery effluent collected from final effluent drainage of a leather-tanning factory in Chrompet, Chennai, Tamil Nadu, India was analysed. Toxicity of treated and untreated tannery effluent was analysed by seed germination test. Results: The lignolytic and constitutive producers of laccase enzyme, C. uredinicola GRDBF21 and B. maydis GRDBF23 exhibited a tolerance index of 1.2 and 1.5, respectively, at 60% effluent concentration. The isolates were able to increase pH and reduce colour, turbidity, total suspended solids and electrical conductivity of the effluent. Besides observing a decrease in the BOD and COD levels, there was also a reduction in the sodium and hexavalent chromium content. C. uredinicola GRDBF21 and B. maydis GRDBF23 treated effluent showed a seed germination percentage of 66.6% and 76.6%, respectively. The untreated effluent completely inhibited the seed germination. Interpretation: The study confirms that the fungal species C. uredinicola GRDBF21 and B. maydis GRDBF23 could be effectively used in decolouration and detoxification of tannery effluent.

Consortium of Microalgae for Tannery Effluent Treatment

Abstract Wastewater generated in tanneries have essential elements for microalgae growth, but it has also some toxic compounds that may hinder or restrain the growth of microalgae in this environment. This work tested microalgae consortium growth originating from a deactivated effluent treatment decanter of a complete tannery (beamhouse to finished leather) for the treatment of wastewater of a tannery processing wet-blue leather to finished leather. It was initially evaluated the growth of the microalgae consortium in the three effluents diluted in 50% distilled water: raw effluent (50RE50W), effluent after primary coagulation/flocculation (50PE50W), and effluent after primary and secondary biological treatment (50BE50W). After 16 days of cultivation, the 50PE50W presented the highest biomass concentration (1.77 g L−1). The highest removal values for effluents 50RE50W, 50PE50W and 50BE50W were 51.02%, 99.90%, 82.88%, and 91.75% for chemical oxygen demand (COD), N-NH3, TKN, and P-PO4-, respectively. It was verified low levels of nutrient removal in the raw effluent (100RE), since the consortium was not able to grow in this medium. Finally, at concentrations of 25RE75BE (25% raw effluent diluted with 75% effluent after the biological treatment) and 50RE50B (50% raw effluent diluted with 50% effluent after the biological treatment), effective removal values were reached. Biomass growth concentration up to 1.3 g L-1 and removal values for N-NH3, TKN, P-PO4, COD, total organic carbon (TOC) and biological oxygen demand (BOD5), of 99.90%, 79.36%, 87.82%, 14.26%, 35.82%, and 42.86%, respectively, were reached in 50RE50B.

Cytotoxicity assays to evaluate tannery effluents treated by photoelectrooxidation / Ensaios de citotoxicidade na avaliação de efluentes de curtume tratados por fotoeletrooxidação

The advanced oxidation process (AOP) is used to increase the treatment efficiency of effluents however, it is necessary to compare the toxicity of treated and untreated effluents to evaluate if the decontamination process does not cause any biological harm. Cultured cells have been previously used to assess the genotoxic and cytotoxic potential of various compounds. Hence, the aim of this work was to assess the applicability of cytotoxicity assays to evaluate the toxicity related to the AOP treatment. Samples of an industrial effluent were collected after their treatment by a conventional method. Cytotoxicity of standard and AOP treated effluents was assessed in CRIB and HEp-2 cell line using the MTT and neutral red assays. We observed decrease at cell viability in the both assays (50% MTT and 13% NRU) when cells were exposed to the AOP treatment in the highest concentration. Thus, cytotoxic assays in cultured cells can be explored as an useful method to evaluate toxicity as well as to optimize effluents treatment process.

Resumo O processo de oxidação avançada (POA) tem sido usado para aumentar a eficiência do tratamento de efluentes; no entanto, é necessário comparar a toxicidade de efluentes tratados e não tratados para avaliar se o processo de descontaminação não é capaz de causar algum risco biológico. Cultivos celulares têm sido utilizados para avaliar o potencial genotóxico e citotóxico de vários compostos. Assim, o objetivo deste trabalho foi avaliar a aplicabilidade de ensaios de citotoxicidade para avaliar a toxicidade relacionada ao tratamento com POA. As amostras de um efluente industrial foram recolhidas após o tratamento por um método convencional. A citotoxicidade dos efluentes padrão e tratado com POA foi avaliada nas linhagens celulares CRIB e HEp-2 usando os ensaios do MTT e do vermelho neutro. Observou-se diminuição da viabilidade celular em ambos os ensaios (50% MTT e 13% VN) quando as células foram expostas à concentração mais elevada do efluente tratado com POA. Assim, os ensaios de citotoxicidade em cultivos celulares podem ser explorados como um método útil para avaliar a toxicidade, bem como para otimizar os processos de tratamento de efluentes.

Sinos River Hydrographic Basin: urban occupation, industrialization and environmental memory / Bacia Hidrográfica do Rio dos Sinos: ocupação urbana, industrialização e memória ambiental.

This article presents an analysis of the process of industrialization and urbanization of the Sinos Valley in Rio Grande do Sul state, Brazil, starting from the establishment of leather goods and footwear manufacturing in the region during the 19th century when tanneries and factories producing footwear and/or components for footwear began to appear, and with special attention to aspects related to the environmental impact on the Sinos river hydrographic basin. The article is based on both bibliographic and documentary research and also draws on biographical narratives of workers with links to the leather goods and footwear industry obtained using ethnographic method. It was found that contemporary environmental conflicts emerge from within a memory of work and an environmental memory in which the factories, the unplanned urbanization, and the utilization of water and other natural resources form a chain of significance. Significance that precludes any form of fragmented analysis that isolates any of these aspects from the others: the economic, socio-historic, cultural, political, or the environmental.

Resumo O artigo aborda o processo de industrialização e urbanização do Vale do Rio dos Sinos/Rio Grande do Sul/Brasil, desde a implantação da indústria coureiro-calçadista na região, no século XIX, com o surgimento dos curtumes e das fábricas de calçados e/ou componentes para calçados, destacando, em especial, os aspectos ligados ao impacto ambiental na Bacia Hidrográfica dos Sinos. Faz-se uso de pesquisa bibliográfica e documental, além da exposição de narrativas biográficas de trabalhadores ligados à indústria coureiro-calçadista, obtidas por meio do método etnográfico. Verifica-se que os conflitos ambientais contemporâneos emergem do interior de uma memória do trabalho e de uma memória ambiental, nas quais a fábrica, a ocupação urbana desordenada, o uso da água e dos demais recursos naturais formam um encadeamento de sentido que impede qualquer análise fragmentada que isole um destes aspectos: o econômico, o socio-histórico, o cultural, o político, o ambiental.

Sinos River Hydrographic Basin: urban occupation, industrialization and environmental memory

This article presents an analysis of the process of industrialization and urbanization of the Sinos Valley in Rio Grande do Sul state, Brazil, starting from the establishment of leather goods and footwear manufacturing in the region during the 19th century when tanneries and factories producing footwear and/or components for footwear began to appear, and with special attention to aspects related to the environmental impact on the Sinos river hydrographic basin. The article is based on both bibliographic and documentary research and also draws on biographical narratives of workers with links to the leather goods and footwear industry obtained using ethnographic method. It was found that contemporary environmental conflicts emerge from within a memory of work and an environmental memory in which the factories, the unplanned urbanization, and the utilization of water and other natural resources form a chain of significance. Significance that precludes any form of fragmented analysis that isolates any of these aspects from the others: the economic, socio-historic, cultural, political, or the environmental.

Resumo O artigo aborda o processo de industrialização e urbanização do Vale do Rio dos Sinos/Rio Grande do Sul/Brasil, desde a implantação da indústria coureiro-calçadista na região, no século XIX, com o surgimento dos curtumes e das fábricas de calçados e/ou componentes para calçados, destacando, em especial, os aspectos ligados ao impacto ambiental na Bacia Hidrográfica dos Sinos. Faz-se uso de pesquisa bibliográfica e documental, além da exposição de narrativas biográficas de trabalhadores ligados à indústria coureiro-calçadista, obtidas por meio do método etnográfico. Verifica-se que os conflitos ambientais contemporâneos emergem do interior de uma memória do trabalho e de uma memória ambiental, nas quais a fábrica, a ocupação urbana desordenada, o uso da água e dos demais recursos naturais formam um encadeamento de sentido que impede qualquer análise fragmentada que isole um destes aspectos: o econômico, o socio-histórico, o cultural, o político, o ambiental.

Cytotoxicity assays to evaluate tannery effluents treated by photoelectrooxidation

The advanced oxidation process (AOP) is used to increase the treatment efficiency of effluents however, it is necessary to compare the toxicity of treated and untreated effluents to evaluate if the decontamination process does not cause any biological harm. Cultured cells have been previously used to assess the genotoxic and cytotoxic potential of various compounds. Hence, the aim of this work was to assess the applicability of cytotoxicity assays to evaluate the toxicity related to the AOP treatment. Samples of an industrial effluent were collected after their treatment by a conventional method. Cytotoxicity of standard and AOP treated effluents was assessed in CRIB and HEp-2 cell line using the MTT and neutral red assays. We observed decrease at cell viability in the both assays (50% MTT and 13% NRU) when cells were exposed to the AOP treatment in the highest concentration. Thus, cytotoxic assays in cultured cells can be explored as an useful method to evaluate toxicity as well as to optimize effluents treatment process.

Resumo O processo de oxidação avançada (POA) tem sido usado para aumentar a eficiência do tratamento de efluentes; no entanto, é necessário comparar a toxicidade de efluentes tratados e não tratados para avaliar se o processo de descontaminação não é capaz de causar algum risco biológico. Cultivos celulares têm sido utilizados para avaliar o potencial genotóxico e citotóxico de vários compostos. Assim, o objetivo deste trabalho foi avaliar a aplicabilidade de ensaios de citotoxicidade para avaliar a toxicidade relacionada ao tratamento com POA. As amostras de um efluente industrial foram recolhidas após o tratamento por um método convencional. A citotoxicidade dos efluentes padrão e tratado com POA foi avaliada nas linhagens celulares CRIB e HEp-2 usando os ensaios do MTT e do vermelho neutro. Observou-se diminuição da viabilidade celular em ambos os ensaios (50% MTT e 13% VN) quando as células foram expostas à concentração mais elevada do efluente tratado com POA. Assim, os ensaios de citotoxicidade em cultivos celulares podem ser explorados como um método útil para avaliar a toxicidade, bem como para otimizar os processos de tratamento de efluentes.

Ecotoxicological evaluation of sediments applied to environmental forensic investigation / Avaliação ecotoxicológica de sedimentos aplicada à perícia criminal ambiental

Abstract The present study aimed to evaluate the potential for using toxicity assays with sediment samples for the detection of water pollution caused by the discharge of tannery effluents into water bodies and its application to environmental forensic investigation. The study included ecotoxicological evaluation of sediments, survey of benthic organisms in the field, as well as chromium, cadmium and lead dosage which provided data for a sediment quality triad evaluation. The sediment samples showed acute and chronic toxicity to the bioindicators, low biodiversity of benthic macrofauna and high chromium concentration, reaching up to 4365 mg.Kg–1. A close relationship was observed between the separate results of ecotoxicological sediment evaluation and the sediment quality triad. The sediment ecotoxicological assessment proved to be applicable to tracking sources of contamination related to tanneries and similar activities in environmental forensics.

Resumo O objetivo do presente estudo foi avaliar o potencial de aplicação de ensaios de toxicidade com amostras de sedimento para constatação de poluição aquática causada por lançamentos de efluentes de curtumes em cursos d’água e seu emprego na perícia criminal ambiental. O estudo incluiu avaliação ecotoxicológica de sedimentos, avaliação da fauna bentônica local e dosagem de cromo, cádmio e chumbo que forneceram dados para avaliação da tríade de qualidade dos sedimentos. As amostras de sedimentos mostraram efeito de toxicidade aguda e crônica aos bioindicadores, baixa biodiversidade da macrofauna bentônica e altas concentrações de cromo que chegaram a 4365 mg.Kg–1. Houve uma estreita relação entre os resultados isolados da avaliação ecotoxicológica e a tríade de qualidade de sedimentos. A avaliação ecotoxicológica demonstrou ser aplicável na identificação de fontes de contaminação relacionadas a curtumes e atividades similares em perícias ambientais.

Evaluation of Microbial Load in Oropharyngeal Mucosa from Tannery Workers

BACKGROUND: Animal skin provides an ideal medium for the propagation of microorganisms and it is used like raw material in the tannery and footware industry. The aim of this study was to evaluate and identify the microbial load in oropharyngeal mucosa of tannery employees. METHODS: The health risk was estimated based on the identification of microorganisms found in the oropharyngeal mucosa samples. The study was conducted in a tanners group and a control group. Samples were taken from oropharyngeal mucosa and inoculated on plates with selective medium. In the samples, bacteria were identified by 16S ribosomal DNA analysis and the yeasts through a presumptive method. In addition, the sensitivity of these microorganisms to antibiotics/antifungals was evaluated. RESULTS: The identified bacteria belonged to the families Enterobacteriaceae, Pseudomonadaceae, Neisseriaceae, Alcaligenaceae, Moraxellaceae, and Xanthomonadaceae, of which some species are considered as pathogenic or opportunistic microorganisms; these bacteria were not present in the control group. Forty-two percent of bacteria identified in the tanners group are correlated with respiratory diseases. Yeasts were also identified, including the following species: Candida glabrata, Candida tropicalis, Candida albicans, and Candida krusei. Regarding the sensitivity test of bacteria identified in the tanners group, 90% showed sensitivity to piperacillin/tazobactam, 87% showed sensitivity to ticarcillin/clavulanic acid, 74% showed sensitivity to ampicillin/sulbactam, and 58% showed sensitivity to amoxicillin/clavulanic acid. CONCLUSION: Several of the bacteria and yeast identified in the oropharyngeal mucosa of tanners have been correlated with infections in humans and have already been reported as airborne microorganisms in this working environment, representing a health risk for workers.

Enhanced production of Aspergillus tamarii lipase for recovery of fat from tannery fleshings

The influence of various oil cakes has been investigated for high level production of lipase using Aspergillus tamarii MTCC 5152. By solid state fermentation in wheat bran containing 2.5% w/w gingili oil cake at 70% v/w moisture content the fungus produced a maximal yield of lipase (758 ± 3.61 u/g) after 5 days of incubation using 2% v/w inoculum containing 10(6) spores/mL. Wheat bran and gingili oil cake with supplementation of gingili oil (1.0% w/w), glucose (0.5% w/w) and peptone (0.5% w/w) gives an increased enzyme production of 793 ± 6.56 u/g. The enzyme shows maximum activity at pH 7.0, temperature 50 °C and was stable between the pH 5.0-8.0 and temperature up to 60 °C. Crude lipase (3%) applied to tannery fleshing shows 92% fat solubility. The results demonstrate that fat obtained from tannery fleshing, a by-product of the leather industry has a high potential for biodiesel production and the proteinaceous residue obtained can be used as animal feed.

Intervenção em saúde do trabalhador em um curtume do Oeste Paulista / Occupational health intervention at a tannery in the west of São Paulo State

O presente trabalho teve o objetivo de avaliar a organização do trabalho, as condições de execução e a insatisfação presentes em um curtume do oeste paulista. A metodologia envolveu a observação do trabalho e a realização de entrevistas semidirigidas com grupos focais de trabalhadores. Em seguida, foi realizada a devolutiva das informações colhidas, permitindo a validação e a refutação de percepções estabelecidas. Os resultados indicaram prejuízos à organização de trabalho que abrangeram a ausência de uniformes e a inexistência de espaços de interlocução com os superiores hierárquicos. As condições de trabalho compreenderam prejuízos à dispersão de gases volatilizados no parque industrial, a utilização de maquinário antigo, com prejuízo à reposição de peças danificadas e a prevenção secundária nas ações de segurança do trabalho. Já a insatisfação envolvia a esvaziada capacidade da hierarquia para resolução de conflitos, a existência de uma cultura reativa em torno de dificuldades laborais e queixas relativas à qualidade do equipamento de proteção individual. Conclui-se destacando que o atendimento às condições críticas apontadas poderia produzir um efeito positivo de reconhecimento dos esforços empregados no cotidiano laboral...

This research aimed to assess the organization of work, working conditions, and dissatisfaction at a tannery in Western São Paulo State. The method involved work observation and semistructured interviews with worker focus groups. The collected information was then reported, allowing the validation and refutation of established perceptions. The results indicated negative effects on the work organization, including the lack of uniforms and the absence of any means for dialog with company management. The working conditions even included harmful effects from the dispersion of volatile gases in the industrial park, and the use of outdated machinery, without the replacement of damaged parts and without minimal prevention in occupational safety actions. Dissatisfaction extended to the organizational hierarchy's total lack of problem-solving ability, the existence of a reactive culture regarding job difficulties, and complaints about the quality of Personal Protection Equipment. In conclusion, it is highlighted that paying attention to the critical conditions pointed out could produce a positive effect of recognizing the efforts made in daily work...

Metagenomic analysis of cadmium and copper resistance genes in activated sludge of a tannery wastewater treatment plant.

In order to comprehensively characterize the copper and cadmium resistance in activated sludge of a tannery wastewater treatment plant, a resistance protein database of the two heavy metals was manually created by retrieving annotated sequences and related information from the public databases and published literatures. The metagenomic DNA was extracted from the activated sludge for Illumina high-throughput sequencing, and the obtained 11,973,394 clean reads (1.61 Gb) were compared against the established databases using BLAST tool. Annotations of the BLAST hits showed that 222 reads (0.019‰) and 197 reads (0.016‰) were identified as copper and cadmium resistance genes, respectively. Among the identified cadmium resistance genes, czcA encoding cobalt-zinc-cadmium resistance protein had the highest abundance (83 reads, 0.0069‰), which was further confirmed by annotation of the open reading frames predicted with the assembly contigs. Among the copper resistance genes, copA (66 reads, 0.0055‰) was most abundant, followed by copK and cusR. Alignment against the Clusters of Orthologous Groups (COG) database also suggested that 87.26% of the matched reads were grouped in COG0474 (cation transport ATPase). This study may be practically helpful for exploring various functional genes in the environment using high-throughput sequencing and bioinformatics methods.

Studies on phyto-genotoxic assessment of tannery effluent and chromium on Allium cepa.

Tannery effluent contributes significantly to pollution of the environment. In this study, phytotoxic and genotoxic effects of tannery effluent and chromium (Cr) were investigated in Allium cepa. For this purpose, tannery effluent was collected from “Up flow Anaerobic Sludge Blanket” (U.A.S.B) Jajmau, Kanpur. A. cepa were exposed to various concentrations of tannery effluent (0.0, 3.125, 6.25, 12.50, 25.0%) and Cr (0.0, 1.0, 2.0, 4.0, 8.0 mg l-1) for 48 and 168 hr. The perusal of data revealed that the physico-chemical characteristics of tannery effluent viz. pH (8.5), EC (11.94 dSm-1), BOD (499 mg l-1), COD (1382 mgl-1) and Cr content (2.32 mg l-1) were much higher than the prescribed permissible limit for industrial effluent discharged into inland waters. These substances provoked phytotoxic and genotoxic effects in A. cepa. Total chlorophyll and protein content in leaves of tannery effluent and Cr treated plants decreased significantly in dose-duration dependent manner. A maximum decrease of 86.29 and 84.26% in total chlorophyll and 81.27 and 76.16% in protein content was observed after 168 hr of exposure while carotenoid content increased up to 6.25% effluent and 2.0 mgl-1Cr treatment and decreased further. In all treated plants, a significant (p>0.05) reduction in root length, mitotic index (MI) and induction in chromosomal (CA)/mitotic (MA) aberration and micronuclei (MNC) were observed as compared to unstressed plants. A maximum reduction of 81.15 and 79.71% in MI, and induction of 6.8 and 4.8% in CA, 29.24 and 26.66% in MA and 0.52 and 0.43% in MNC were found at 12.50% effluent and 4 mgl-1 Cr treated plants as compared to unstressed plants, however at highest effluent and Cr concentration both the plants showed pyknosis condition after 168 hr.

Chromium accumulation in submerged aquatic plants treated with tannery effluent at Kanpur, India.

Aquatic macrophytes have been widely studied because of their capability of absorbing contaminants from water and their subsequent use in biomonitoring. This study presents a comparison of Cr accumulating potential of submerged aquatic plants viz Vallisneria spiralis and Hydrilla verticillata. These plants were treated with various concentrations of treated tannery effluent collected from UASB, Jajmau, Kanpur under repeated exposure in controlled laboratory conditions in order to assess their maximum bioaccumulation potential. The maximum accumulation of 385.6 and 201.6 μg g-1 dry weight was found in roots of V. spiralis and the whole plants of H. verticillata, respectively at 100% concentration after 9th day of effluent exposure. The chlorophyll and protein content of both species decreased with increase in effluent concentration and duration. At highest concentration and duration a maximum reduction of 67.4 and 62.66% in total chlorophyll content, 9.97 and 4.66% in carotenoid content and 62.66 and 59.36% in protein content was found in V. spiralis and H. verticillata respectively. Anatomical studies in both V. spiralis and H. verticillata was carried out to assess the effects of metal accumulation within the plants. Changes in the anatomical structures of both plants exhibits the capacity of these species to act as indicator of effluent toxicity. The high accumulation potential of Cr by both plants revealed their capability to remove pollutants from effluent.

Characterization of a novel lipase from Bacillus sp. isolated from tannery wastes

Kinetics of a lipase isolated from Bacillus sp. was studied. The enzyme showed maximum activity at pH 9 and temperature 60ºC. The Michaelis constant (K M 0.31 µM) obtained from three different plots i.e., Lineweaver-Burk, Hanes-Wolf and Hofstee, was found to be lower than already reported lipases that confirmed higher affinity of the enzyme for its substrate p-NPL (p-nitrophenyl laurate). Vmax of the enzyme was found to be 7.6 µM/mL/min. Energy of activation calculated from Arrhenius plot was found to be 20.607 kJmol-1. Activation enthalpy (ΔH*) had negative trend and the value for the hydrolysis of p-NPL by the enzyme at optimum temperature was -2.748 kJmol-1 . Activation entropy (ΔS*) and free energy of activation (ΔG*) of the enzyme were found to be 1.468 Jmol-1K-1 and -3.237 kJmol-1, respectively at optimum temperature. Low value of Q10 (0.04788) shows high catalytic activity of the enzyme. Mn2+, Fe2+ and Mg2+ enhanced the lipase activity whereas Cu2+, Na+ and Co2+ inhibited the enzyme activity. However, the enzyme activity was not affected significantly by K+ ions. EDTA and SDS also significantly inhibited the lipase activity. Activity of the enzyme was increased in n-hexane while decreased with increase in concentration of acetone, chloroform, ethanol and isopropanol.

Viabilidade do uso de resíduos da agroindústria coureiro-calçadista no solo / Viability of using tannery and leather residues in the soil

As indústrias couro-calçadistas geram grandes quantidades de resíduos que contém cromo, produto utilizado no curtimento do couro. Para avaliar os efeitos de três aplicações de lodo de curtume (LC), resíduo de rebaixadeira (RR) e aparas de couro (AC) sobre o rendimento do sorgo (Sorghum graniferum) e rabanete (Raphanus sativus), foi conduzido um experimento em colunas de PVC, com três tipos de solo, durante o período de 1996 a 1999. Foram determinados no solo os valores de pH e o teor de cromo, bem como o teor de cromo nas partes comestíveis das plantas. Os resíduos não afetaram o crescimento das plantas, quando foram feitas a calagem e a adubação mineral. O LC pode neutralizar a acidez do solo e suprir nitrogênio para as plantas. O teor de cromo nas partes comestíveis das plantas aumentou com a aplicação sucessiva dos resíduos, estando, entretanto, sem exceder os teores aceitáveis para o consumo. Não foi observada a mobilidade de cromo para as camadas subsuperficiais do solo.

Tannery and leather industries generate high amounts of residues often containing chromium used as a tanning agent. To evaluate the effects of three applications of tannery sludge (TS), leather shavings (LS) and leather shreds (LS) on sorghum (Sorghum graniferum) and radish (Raphanus sativus), a microplot experiment with tree soil types was conducted during the 1996 to 1999 period. Soils pH and Cr contents in plants' edible parts were determined. The residues did not affect plant growth, when properly limed and fertilized. The TS can neutralize soil acidity and supply N for the plants. Plant Cr contents in the edible parts increased with residues application, being however on the range appropriate for consumption. It was not observed Cr mobility to the soil subsurface layers.

Impact of rhizobacteria on growth and chromium accumulation in Scirpus lacustris L. grown under chromium supplementation.

Four chromate tolerant rhizobacterial strains viz., RZB-01, RZB-02, RZB-03 and RZB-04 were isolated from rhizosphere of Scirpus lacustris collected from Cr-contaminated area. These strains characterized at morphological and biochemical levels. The most efficient chromate tolerant strain RZB-03 was inoculated to fresh plant of S. lacustris and grown in 2 μg ml -1 and 5 μg ml -1 of Cr +6 supplemented nutrient solution under controlled laboratory condition. The effects of rhizobacterial inoculation on growth and chromium accumulation in S. lacustris were evaluated. The inoculation of rhizobacteria increased biomass by 59 and 104%, while total chlorophyll content by 1.76 and 15.3% and protein content increased by 23 and 138% under 2 μg ml -1 and 5 μg ml -1 concentrations of Cr +6, respectively after 14 d as compared to non-inoculated plant. Similarly, the Cr accumulation also increased by 97 and 75% in shoot and 114 and 68% in root of inoculated plants as compared to non inoculated plants at 2 μg ml-1 and 5 μg ml-1 Cr+6 concentrations, respectively, after 14 d. The chromate tolerant rhizobacteria which play an important role in chromium uptake and growth promotion in plant may be useful in development of microbes assisted phytoremediation system for decontamination of chromium polluted sites.

Tratabilidad del efluente de una tenería con presencia de cromo usando un reactor por carga secuencial / Tratability of Tannery Wastewater in the Presence of Chromium Usinga Sequencing Batch Reactor

Los efluentes industriales de las tenerías son altamente contaminantes por las elevadas concentraciones de materia orgánica, nitrógeno y metales pesados como el cromo que contienen. Los sistemas biológicos no convencionales, en especial los que usan reactores por carga secuencial (SBR) han demostrado ser una buena opción de tratamiento de estos efluentes por su flexibilidad y eficiencia en presencia de sustancias inhibidoras, tales como el cromo. El objetivo de esta investigación fue evaluar la eficiencia de un SBR en cuanto a la remoción de materia orgánica, nutrientes y metales pesados utilizando una mezcla de dos de las fracciones de los vertidos de una tenería (curtido con cromo y teñido). Se compararon las eficiencias de remoción obtenidas al alimentar el reactor con afluentes diluidos y concentrados, variando el tiempo de residencia hidráulica en 8 y 12 horas. Durante el tiempo de reacción se combinaron fases anóxicas y óxicas. Se obtuvo que las remociones de contaminantes fueron estadísticamente mayores cuando se usaron afluentes diluidos (DQO£1000 mg/L y [Cr3+]£10 mg/L), independientemente del tiempo de retención utilizado, lográndose la mayor eliminación durante la fase anóxica. Las remociones no mostraron diferencia estadística entre ellas, oscilando para los tratamientos con afluentes diluidos entre 82,5 y 84,2% para la DQO; 58,0 y 73,9% para P-PO4(3-) y 51,2 y 53,9% para el Cr. La eliminación de nitrógeno se realizó por asimilación debido a que los microorganismos nitrificantes fueron más sensibles e inhibieron su actividad frente a la presencia del cromo y altas concentraciones de materia orgánica. La remoción de cromo se logró por precipitación y/o adsorción en el lodo, por lo que fue fundamental controlar el pH en los reactores entre 7,5 y 8,5 unidades.

Tannery wastewater are highly pollutant for the high concentrations of organic matter, nitrogen and heavy metals as chrome that they contain. Sequential batch reactors (SBR) have demonstrated to be a good option of treatment of these effluents due to their flexibility and efficiency in presence of inhibiting substances (chrome). The aim of this investigation was to determine the best conditions for removal of organic matter, nutrients and heavy metals of the residual water of a tannery using a SBR fed on a mixture of tanning-dyeing effluent. The efficiencies of removal were compared when using dilute and concentrated influents, under 8 and 12 hour of hydraulic residence time. During the reaction phases anoxics and oxics phases were combined. The removal of pollutants were significantly higher when dilute influent was used (DQO£1000 mg/L and [Cr3+]£10 mg/L), independently of the retention time, being achieved the major elimination during the anoxic phase. The removals fluctuated between 82.5 and 84.45% of DQO, 58.0 and 73.9% of P-PO4(3-) and 51.2 and 53.9% of Cr. The elimination of nitrogen was achieved by assimilation, due to the fact that nitrifying bacteria were more sensitive and their activity was inhibited by the presence of chrome and high concentrations of organic matter. The removal of chrome was achieved by precipitation and/or adsorption on the sludge, being necessary to control the pH between 7.5 - 8.5 in the reactors.