Delhi Stretch Research Articles

Assessment of Heavy Metals in the Sediments of Delhi Stretch of River Yamuna, India: Impact of Wastewater Discharge

Assessment of Heavy Metals in the Sediments of Delhi Stretch of River Yamuna, India: Impact of Wastewater Discharge

Impact of Covid-19 on Yamuna River water quality: Possible ways to rejuvenate the riverine ecosystem in national capital of India

The water quality of Yamuna River was studied for four years from 2019 until August 2022. The period witnessed the onset of COVID-19 pandemic and government-imposed complete lockdown which caused slight improvement in the water quality. Five parameters pH, Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Dissolved Oxygen (DO) and Faecal Coliform (FC) monitored by Delhi Pollution Control Committee (DPCC) were analyzed to see the changes in water quality of Yamuna River in the Delhi stretch before the onset of COVID-19 (2019), during the COVID-19 (2020 and 2021) and after the pandemic (2022). Maximum improvement in some water quality parameters were observed only during the 1st lockdown in the year 2020 when government had imposed complete restriction on the movement of people and industries were not functioning at there maximum capacity. The water quality again declined in the year 2021 and further in the year 2022. Major cause of pollution was the untreated waste reaching the river from various drains. Therefore, it is extremely important to intersect all the major and minor drains through Sewage Treatment Plants (STPs). The floodplain of the river needs to be managed to keep the pollution in control.

Profiling of Antibiotic Residues in Soil and Vegetables Irrigated Using Pharmaceutical-Contaminated Water in the Delhi Stretch of the Yamuna River, India

The movement of emerging pollutants, particularly antibiotics, from surface water to crops through the process of plant uptake poses a significant public concern related to the agricultural utilization of untreated water and biosolids. It is essential to consider the potential risk of inadvertent human exposure and the accumulation of drug residues in fresh food crops, particularly in the case of various green vegetables. Nowadays, environmental research is mainly focusing on the bioaccumulation and threat posed by pharmaceutical residues, especially antibiotics and personal care products in the soil–plant ecosystem. In the present study, the concentration of pharmaceuticals in soil samples collected from agricultural fields irrigated with Yamuna water were evaluated using suitable extraction and sophisticated instrumentation techniques. Out of the five sampling locations, the highest concentration of ofloxacin was reported at Site-V (0.265 µg/mg) during the premonsoon period and the lowest concentration (0.014 µg/mg) during the postmonsoon at Site-II, in terms of the average concentration; this could be due to the combined effect of anthropogenic activities, surface water runoff, and the combined load of drains in the vicinity. For the quantification of the selected antibiotics in a green leafy vegetable (Spinach oleracea), the concentration of ofloxacin was found to be the highest at Okhla barrage Site-V (5.586 µg/mg) during the premonsoon period, with the lowest concentration observed at Site-I, from 1.382 µg/mg to 1.698 µg/mg, during the postmonsoon period. The higher concentration of ofloxacin in crops is because of its susceptibility to being absorbed at the soil’s surface. Plant absorption of antibiotics is influenced primarily by the biological characteristics of the plant, encompassing factors like the lipid and carbohydrate composition of the plant roots. Additionally, the physiochemical properties of the drugs, including molecular size, Kow, and pKa, play a significant role in this process. The antibiotics showed greater variation in their concentration during the premonsoon than in the postmonsoon period, which may be because of precipitation, dilution, and the leaching effect of the soil. For all three of the drugs studied, the concentrations followed the order of ofloxacin > amoxicillin > erythromycin. Thus, the effective management of contaminated soils and vegetables must consider continuous monitoring and risk assessment of high-priority antibiotics to prevent negative effects on the natural environment and human health.

Implication of dissolved nitrogen dynamics of urban rivers using multivariate regression and structural equation modeling

AbstractThe river's functional balance varies according to flow regimes and nutrient distribution. Watercourses can receive water from different point and nonpoint sources, which discharge high nitrogen load in rivers generated from domestic and industrial effluents and agricultural runoff. The excessive concentration of nitrogen load affects the riverine ecosystem by attenuating dissolved oxygen balance and disturbing the water quality. A study has been conducted to determine the nitrogen dynamics and their impact on the water quality of the Delhi stretch of Yamuna River, India, which is highly influenced by anthropogenic activities. Multivariate linear regression (MLR) was performed to gain insight into nitrogen dynamics, and structural equation modeling was applied to determine the direct (primary) and indirect (secondary) relation between the water quality parameters and the subsequent impact on water quality. Dissolved inorganic nitrogen (DIN) was measured using ammonia, nitrate, and nitrite, and total Kjeldahl nitrogen was estimated to reflect the dissolved organic nitrogen (DON). The variation in dissolved nitrogen (organic and inorganic) signifies high negative flux on the river's organic content, causing further degradation of river water quality. MLR predicted a high correlation between predicted and observed DIN at the Income Tax Office (ITO) (92.5%) and Nizamuddin (94.37%) and DON at ITO (93.49%) and Nizamuddin (95.28%). The high concentration during the lean period deteriorates the water quality tremendously and suggests that the variation in dissolved nitrogen content should be monitored carefully to maintain the river's water quality dominated by the organic load.

Water quality simulation under river restoration measures for the Delhi stretch of river Yamuna, India

Water quality simulation under river restoration measures for the Delhi stretch of river Yamuna, India

Multi-objective waste load allocation: application to Delhi stretch of the river Yamuna, India

Multi-objective waste load allocation: application to Delhi stretch of the river Yamuna, India

Multiobjective Wasteload Allocation: Application to Delhi stretch of the river Yamuna, India

Multiobjective Wasteload Allocation: Application to Delhi stretch of the river Yamuna, India

Investigations on the co-occurrence of microplastics and other pollutants in the River Yamuna, Delhi

Abstract The Yamuna River is a threatened resource of freshwater in Delhi, India. The present study is focused on investigating three important contaminants, namely microplastics (MPs), heavy metals, and fecal coliforms in the surface water of the river, with major emphasis on MPs occurrence and characterization. MPs showed an increase in abundance in the river from the Wazirabad barrage (n = 500 MPs/m3) to the Okhla barrage downstream (n = 3,900 MPs/m3) in Delhi, with a maximum abundance downstream to the Najafgarh and Shahdara drain outfalls. White color and fragmented shape were prevalent characteristics of the isolated MPs. Attenuated total reflectance–Fourier transform infrared (ATR-FTIR) spectroscopy revealed five types of polymers. Heavy metals (chromium, lead, manganese, and iron) and fecal coliforms were at unacceptable levels at most of the sampling sites. Due to the emergence of issues concerning the tendency of MPs to actively interact with heavy metals and pathogenic microorganisms, investigation of the co-occurrence of such harmful pollutants is very important. The present study is aimed at this issue and urges similar kinds of investigations in other riverine regions of our country, as well as globally, due to their scarcity in literature. This study can further provide a baseline database to help the Government of India's efforts to clean and revive the Delhi stretch of the Yamuna River.

ASSESSMENT OF WATER QUALITY OF RIVER YAMUNA USING POLLUTION INDICES

The river Yamuna is considered a crucial river in the Indo-Gangetic plain. Having 0.4 Percent of the catchment area in the National Capital Territory (NCT) of Delhi, it feeds about 70 per cent of the population of Delhi and hence, is a major source of dependency for NCT of Delhi. The water quality monitoring of River Yamuna is done by the Delhi Pollution Control Committee (DPCC), Delhi on monthly basis.The objective of the study is to investigate the water quality of the river in the Delhi stretch, for the period 2003-2021. The water quality data has been derived from experimental analysis at DPCC across seven monitoring stations and has been analysed in the present study. It has been revealed that pollutant load from urban local bodies and drains have a stronger impact on the water parameters after the Wazirabad in Delhi, resulting in deteriorated water quality and high-Water Quality Indices (WQI). Water Quality Index (WQI) for the year 2021 indicates that pollution in the river Yamuna increases during monsoon and post-monsoonperiods while during pre-monsoon it remains relatively low.The average pH of the river water ranges from 6 to 8 throughout the year. The comparative data reveals that dissolved oxygen (DO) at most of the sites (except Palla) is nil and, the values of BiochemicalOxygen Demand(BOD) and Chemical Oxygen Demand (COD) have been increasing tremendously, which is due to the unregulated discharge or dumping of sewage water from urban local bodies (ULB) in the river.

Dissolved oxygen modelling of the Yamuna River using different ANFIS models.

Dissolved oxygen (DO) is one of the prime parameters for assessing the water quality of any stream. Thus, the accurate estimation of DO is necessary to evolve measures for maintaining the riverine ecosystem and designing appropriate water quality improvement plans. Machine learning techniques are becoming valuable tools for the prediction and simulation of water quality parameters. A study has been performed in the Delhi stretch of the Yamuna River, India, and physiochemical parameters were examined for 5 years to simulate the DO using various machine learning techniques. Simulation and prediction competencies of adaptive neuro fuzzy inference system-grid partitioning (ANFIS-GP) and subtractive clustering (ANFIS-SC) were performed on high dimensional river characteristics. Four different models (M1, M2, M3 and M4) were developed using different combination of input parameters to predict DO. Results obtained from the models were evaluated using root mean square error and coefficient of determination (R2) to identify the appropriate combination of parameters to simulate the DO. Results suggest that both types of ANFIS models work adequately and accurately predict the DO; however, ANFIS-GP outperforms the ANFIS-SC. M4 generated R2 of 0.953 from ANFIS-GP compared to 0.911 from ANFIS-SC.

Assessment of toxicity and potential health risk from persistent pesticides and heavy metals along the Delhi stretch of river Yamuna

The present study aims at the assessment of environmental quality of the most polluted stretch of river Yamuna along the megacity of Delhi. The study was conducted in order to examine toxicity and health hazards associated with persistent pollutants present in the fluvial ecosystem. Eighty four sediment and 56 vegetable samples from same locations were collected from the Delhi segment of river Yamuna flood plain in order to examine 20 organochlorine pesticides (OCPs) and 9 heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn). Both the organic and inorganic groups of persistent toxic substances were monitored and analysed for the extent of eco-toxicological as well as dietary health risks posed to the local population. Eco-toxicological assessment was done based on sediment quality guidelines, enrichment factor, geo-accumulation index, degree of contamination and Pollution Load Index. The dietary-risk was assessed with the help of translocation factors (TF) of these pollutants in vegetables. Carcinogenic and non-carcinogenic health risks from consumption of vegetables were also investigated.The level of concern for heavy metals was greater than that of OCPs as per the sediment quality guidelines. DDT, Cd, Pb and Zn had maximum concentrations corresponding to level 3 of concern, while Cr and Ni reached up to the highest i.e., 4th level of concern. Sediment samples were found to be enriched and contaminated significantly with Cd and moderately with Pb, as represented respectively by enrichment factors and contamination factors (CF). CF for metals lied in order Zn > Cd > CrNi > PbCu. Pollution load index was highest at the location lying on the exit point of Yamuna in Delhi. TF values greater than 1 were observed in majority of samples analysed for Ni, Cr, Cu and Zn. Spinach topped among vegetables in terms of metal contamination. Cd, Ni and Pb accumulated more in the roots, as against Mn, Zn, Cu and Cr which had higher accumulation in the shoots. Translocation factors were substantially high in vegetables for most of the OCPs, clearly indicating bioaccumulation and potential health risk to the consumers. Health risk to humans was assessed for non-carcinogenic and carcinogenic potentials from ingestion of vegetables. Hazard Quotient (HQ) > 1 due to radish (roots and leaves) and cauliflower consumption in children indicated non-carcinogenic risk. Hazard Index (HI) beyond 1 for all the vegetables (except onion leaves) confirmed substantial cumulative risk. Lifetime cancer risk (LCR) revealed moderate (spinach, radish, beet root and cauliflower) to low (all the others) levels of carcinogenic risk to humans. Cancer risks from γ-HCH, β- HCH, Hept, Hept Ep, Ald, p,p’-DDT, and Cr exposure through the food chain could be well established.

Seasonal variation of potentially toxic metal contamination in Yamuna riverine ecosystem, Delhi, India.

The River Yamuna in Delhi region, the National Capital Territory (NCT) of India, carries potentially toxic metals such as Cr, Pb, Mn, Mg, Hg, Fe and Zn. These contaminants are discharged mainly from industrial wastes, agricultural and household activities and domestic sewage. A total of 12 stations (2.5 to 3.5km apart from each other) were selected for the study, covering the upstream and downstream areas of river Yamuna in Delhi. The investigated sites were evaluated for significant difference between upstream and downstream locations of river Yamuna in three different time periods (June, October, February). Metal contamination were measured in water, sediments (2μm) and nearby agriculture soil of the river Yamuna, and found with high metal loads as compared with the international standards, chiefly in the downstream sites as the river flows through the Delhi stretch. The multivariate statistical analysis revealed spatial and temporal variations in the metal concentrations which suggest seasonal variation and common point source of some metals while different sources of other metals. The contamination of the river water and adjoining agriculture soils points towards possible entry of these metals into the food chain. The study indicates that considering the current status of metal pollution, the surface water is not in good conditions for use as drinking purpose because of the high concentrations of few potentially toxic metals. Our study recommends regular monitoring of toxic metals in Yamuna river water and sediments, strict ban on the domestic, agriculture and industrial waste disposal for the restoration of the river to its natural state.

Impact of Lockdown on Health of the Yamuna river at Delhi Stretch, India

Present study points out the impact of Lockdown on the health of the Yamuna river at Delhi stretch by comparing prelockdown and Post-lockdown period by studying the reports of pollution monitoring agencies. Delhi segment of the Yamuna is highly polluted, where alongwith domestic sewage a huge quantity of industrial waste is being discharged continuously without proper treatment. Pre lockdown (March 2020) water quality parameters at three sampling stations named as Palla, Nizammuddin Bridge and Okhla barrage U/s in Delhi were, pH were 8.7, 7.3 and 7.2, DO were 17.1 mg/L, not detected in later two sites, BOD were 7.9 mg/L, 57 mg/L and 27 mg/L and COD were 28 mg/L, 90 mg/L and 95 mg/L respectively and postlockdown period (April 2020) the pH was 7.8, 7.2 and 7.1, DO was 8.3 mg/L, 2.4 mg/L and 1.2 mg/L BOD was 2 mg/L, 5.6 mg/ L and 6.1 mg/L and COD were 6 mg/L, 16 mg/L and 18 mg/L respectively. The study of these parameters at three sampling stations reveals that the lack of industrial pollutants discharging due to nationwide lockdown for COVID-19 pandemic had positive effect on water quality of this river. Water quality could be maintained by planned establishment of industries and setup of ETP with without gap between generation and treatment.

Pharmaceutical disposal facilitates the mobilization of resistance determinants among microbiota of polluted environment

The emergence of resistance on exposure to pharmaceuticals among microorganisms has raised serious concern in the therapeutic approach against infectious diseases. Effluents discharge from hospitals, industries, and urban settlements containing pharmaceuticals and other toxic compounds into the aquatic ecosystem selects bacterial population against them; thereby promotes acquisition and dissemination of resistant traits among the inhabitant microbiota. The present study was aimed to determine the prevalence and multidrug resistance pattern of Extended Spectrum β-lactamase (ESBL) producing and non-producing bacterial isolates from the heavily polluted Delhi stretch of river Yamuna, India. Additionally, the role of abiotic factors in the dissemination of conjugative plasmids harbouring resistance genes was also studied using E. coli J53 as recipient and resistant E. coli isolates as donor strains. Of the 227 non-duplicate bacterial isolates, 60% (136) were identified as ESBL+ and 40% (91) as ESBL. ESBL+ isolates were found highly resistant to β-lactam and non-β-lactam classes of antibiotics compared with the ESBL− isolates. 68% of ESBL+ and 24% of ESBL− isolates showed an MAR index of ≥0.5. Surprisingly, multidrug resistance (MDR), extensively drug resistance (XDR), and pandrug resistance (PDR) phenotype were observed for 78.6%, 16.9%, and 0.7% of ESBL+ and 90%, 3%, and none for PDR among ESBL− isolates. Conjugation under different conditions showed a higher mobilization rate at neutral pH (7–7.5) for ESBL+ isolates. Conjugation frequency was maximum at 40 °C for the isolate E. coli MRB6 (4.1 × 10−5) and E. coli MRE32 (4.89 × 10−4) and at 35 °C for E. coli MRA11 (4.89 × 10−5). The transconjugants obtained were found tolerating different concentrations of mercuric chloride (0.0002–0.2 mg/L). Increased biofilm formation for ESBL+ isolates was observed on supplementing media with HgCl2 (2 μg/mL) either singly or in combination with CTX (10 μg/mL). The present study demonstrates that anthropogenically influenced aquatic environments act as a reservoir of MDR, XDR, and even PDR strains; thereby posing a potent public health risk.

Taxonomic resolution of Stylonychia notophora (Alveolata, Ciliophora, Hypotricha) sensu Sapra and Dass 1970 using an integrative approach.

The spirotrichean ciliate Stylonychia notophora has previously been recorded in India although the descriptions are lacking in detail. It has been suggested several times that the Indian population, S. notophora sensu Sapra and Dass, 1970 collected along the Delhi stretch of the River Yamuna, is identical to Tetmemena pustulata, but this has never been confirmed due to insufficient data for the former. The present study includes detailed descriptions (classical and molecular) of populations of Tetmemena isolated from six locations along the River Yamuna, India. These include four from the Delhi stretch including that from which Sapra and Dass, 1970 isolated their population of S. notophora. Due to the lack of a sufficiently detailed description, the taxonomic status of S. notophora sensu Sapra and Dass, 1970 was not clear. Comparisons among the populations isolated in the present study with previous descriptions of T. pustulata and S. notophora sensu Sapra and Dass, 1970 show only minor differences in morphometry, morphogenesis and in 18S rDNA sequences. The 18S rDNA sequences of all six populations had 99% similarity to both T. pustulata and S. notophora. These findings support the contention that S. notophora sensu Sapra and Dass, 1970 was misidentified and is a population of T. pustulata. This study supports the need for adopting an integrative approach based on morphological, morphogenetic and molecular data in order to understand species delimitation in ciliated protists.

Assessment of Water Quality of Najafgarh Drain and Its Impact on River Yamuna

Water is one of the basic amenities of life and Yamuna is a major source of water supply for Delhi and nearby states of Haryana, Uttar Pradesh, and Rajasthan etc. Due to the rapid growth of industries and advanced agricultural activities in and around national capital territory Delhi, the deterioration of Yamuna River has become a major concern. The objective of this study is to assess the Water Quality of Najafgarh drain and unveil the present deteriorated condition of Yamuna River in Delhi. A comparison has been made between the water quality of river Yamuna before and after the confluence of Najafgarh Drain into it. The present situation and contamination level of River has been analyzed due to various drains present in the Delhi stretch. The effect of pollution load and waste water added to Yamuna in Delhi is studied by comparing the water quality in river Yamuna at Palla (before entering in Delhi) and at Okhla barrage (the downstream point from where the river Yamuna meets Agra canal and leaves Delhi.). For the study, water samples were collected from six different locations in river and Najafgarh Drain. Experimental results indicated that the water quality of river was comparable with the Drain as most of the parameters were exceeding the prescribed standards for surface water. Overall the study concluded that Yamuna River has been converted into a Drain in Delhi stretch and its water is not suitable for any other purposes without proper and highly efficient treatment system.

Simulating strategic measures for managing water quality in the Delhi stretch of the River Yamuna, India

The 22 km-long Delhi stretch of river Yamuna, India is highly polluted because of discharge of untreated wastewater. In this study, various pollution abatement measures such as wastewater treatment, flow augmentation, and diversion are explored using simulation models to evolve strategic measures, policies, and guidelines for improving the river water quality. Three cases viz, Case A: existing layout with all 15 drains (D1–D15) discharging; Case B: layout after diversion of the Najafgarh drain (D1); and Case C: layout after diversion of all drains (D2–D15) other than Najafgarh drain are conceptualized. A total of 34 scenarios characterizing different levels of wastewater treatment, flow augmentation, and drain diversion, as standalone and considered in combination are simulated using the QUAL2E water-quality simulation model. Results reveal that tertiary treatment at all the drains (D1–D15) outfall under the existing layout, i.e., Case A, would be the most feasible option, whereas flow augmentation alone is not.

Co-occurrence of ESBLs and silver resistance determinants among bacterial isolates inhabiting polluted stretch of river Yamuna, India

In this study, we investigated the prevalence of ESBLs producing bacteria from highly polluted stretch of river Yamuna and co-occurrence of ESBLs and silver resistance gene among tested isolates. Water samples were collected from ten different polluted sites from Delhi stretch of river Yamuna, India. Out of 399 non-duplicate isolates screened, 121 (~ 30%) were found to be ESBLs producers. ESBLs positive isolates showed high level of resistance for β-lactam and non-β-lactam antibiotics, viz. ampicillin, cephalosporins, ciprofloxacin and polymyxin-B. A significantly high level of resistance (26.4%) was observed for last resort antibiotic colistin. 69% of ESBLs positive isolates exhibited multidrug resistance phenotype and high MAR index of different sampling sites ranging from 0.21 to 0.68. Molecular characterization revealed that blaCTX-M was the most prevalent type of ESBL (60.3%) followed by blaTEM (47.9%) and blaSHV (15.7%). We further observed co-occurrence of silver resistance determinants silE, silP and silS in 49.3%, 53.4% and 36.9% isolates harboring blaCTX-M genes. Conjugation transfer assay confirmed the successful transfer of plasmid encoding ESBLs and silver resistance determinants together. To the best of our knowledge, this is first report of co-occurrence of CTX-M and silver resistance gene from aquatic environment. Moreover, this study reports occurrence of ESBL genes in Bacillus safensis and Brachymonas chironomi not reported earlier. Co-occurrence of sil and blaCTX-M gene strengthens the hypothesis of heavy metal exert selection pressure for the emergence of antibiotic resistance.

Prevalence and Molecular Characterization of ESBL Producing Enterobacteriaceae from Highly Polluted Stretch of River Yamuna, India

The rapid increase in number and diversity of Extended Spectrum β-Lactamases (ESBLs) producing Enterobacteriaceae in natural aquatic environment is a major health concern worldwide. This study investigates abundance and distribution of ESBL producing multidrug resistant Enterobacteriaceae and molecular characterization of ESBL genes among isolates from highly polluted stretch of river Yamuna, India. Water samples were collected from ten different sites distributed across Delhi stretch of river Yamuna, during 2014-15. A total of 506 non duplicate Enterobacteriaceae isolates were obtained. Phenotypic detection of ESBL production and antibiotic sensitivity for 15 different antibiotics were performed according to CLSI guidelines (Clinical and Laboratory Standard Institute, 2015). A subset of ESBL positive Enterobacteriaceae isolates were identified by 16S rRNA gene and screened for ESBL genes, such as blaCTX-M, blaTEM and blaOXA. Out of 506 non-duplicate bacterial isolates obtained, 175 (34.58%) were positive for ESBL production. Susceptibility pattern for fifteen antibiotics used in this study revealed higher resistance to cefazolin, rifampicin and ampicillin. A high proportion (76.57%) of ESBL positive isolates showed multidrug resistance phenotype, with MAR index of 0.39 at Buddha Vihar and Old Delhi Railway bridge sampling site. Identification and PCR based characterization of ESBL genes revealed the prevalence of blaCTX-M and blaTEM genes to be 88.33% and 61.66%, respectively. Co-occurrence of blaCTX-M and blaTEM genes was detected in 58.33% of the resistant bacteria. The blaOXA gene was not detected in any isolates. This study highlights deteriorating condition of urban aquatic environment due to rising level of ESBL producing Enterobacteriaceae with multidrug resistance phenotype.

Study of pandrug and heavy metal resistance among E. coli from anthropogenically influenced Delhi stretch of river Yamuna.

Escalating burden of antibiotic resistance that has reached new heights present a grave concern to mankind. As the problem is no longer confined to clinics, we hereby report identification of a pandrug resistant Escherichia coli isolate from heavily polluted Delhi stretch of river Yamuna, India. E. coli MRC11 was found sensitive only to tobramycin against 21 antibiotics tested, with minimum inhibitory concentration values >256 μg/mL for amoxicillin, carbenicillin, aztreonam, ceftazidime and cefotaxime. Addition of certain heavy metals at higher concentrations were ineffective in increasing susceptibility of E. coli MRC11 to antibiotics. Withstanding sub-optimal concentration of cefotaxime (10 μg/mL) and mercuric chloride (2 μg/mL), and also resistance to their combinatorial use, indicates better adaptability in heavily polluted environment through clustering and expression of resistance genes. Interestingly, E. coli MRC11 harbours two different variants of blaTEM (blaTEM-116 and blaTEM-1 with and without extended-spectrum activity, respectively), in addition to mer operon (merB, merP and merT) genes. Studies employing conjugation, confirmed localization of blaTEM-116, merP and merT genes on the conjugative plasmid. Understanding potentialities of such isolates will help in determining risk factors attributing pandrug resistance and strengthening strategic development of new and effective antimicrobial agents.