Biomedical waste management in nursing homes and smaller hospitals in Delhi

The management of biomedical waste is a crucial issue in health and environmental management. Rules in India were promulgated in 1998, originally with a deadline of December 2000 and extended to December 2002; however, the actual situation remains far from satisfactory. A study conducted in 2001 by CEE, New Delhi; indicated an implementation deficit. To gauge the present situation, a survey was undertaken during 2005-2006. A systematic analysis of current biomedical waste management practices in smaller nursing homes and hospitals in Delhi was carried out. A total of 53 nursing homes, with bed strengths ranging from 20 to over 200, were included. The survey results show that there is a marked improvement in the segregation practices of biomedical waste in small private hospitals and nursing homes. The majority of nursing homes and hospitals were found to be using a service provider for the collection, management, and disposal of healthcare wastes. Data was collected through a questionnaire and field visits. This paper discusses the relevant data indicative of current practices of healthcare waste management in the nursing homes and small healthcare facilities in Delhi.     

Forced dispersion of LNG vapor with water curtain

Installation of effective safety measures to prevent and mitigate an accidental LNG release is critical. Water curtains are usually inexpensive, simple and reliable and currently have been recognized as an efficient technique to control and mitigate various hazards in the process industries including LNG industry. Actions of a water spray consist of a combination of several physical mechanisms. Detailed analysis of the complex mechanisms and the effects of water spray features to control and mitigate potential LNG vapor cloud are still unclear. This paper discusses the experimental research conducted by MKOPSC to study the physical phenomena involved and the effect of different types of water curtains parameters when applied for LNG vapor. The data from medium scale out-door experiments at the Brayton Fire Training School (BFTF), Texas, are summarized here to understand the relative importance of induced mechanical mixing effects, dilution with air, and heat transfer between water droplets and the LNG vapor. Field test results have determined that water curtains can reduce the concentration of the LNG vapor cloud. Due to the water curtain mechanisms of entrainment of air, dilution of vapor with entrained air, transfer of momentum and heat to the gas cloud, water curtain can disperse LNG vapor cloud to some extent.     

Screening of human health risk to infants associated with the polychlorinated biphenyl (PCB) levels in human milk from Punjab Province,Pakistan

This study assessed the polychlorinated biphenyl (PCB) levels in human milk and its associated health risk to infants from rural and urban settings of five districts of Punjab Province, Pakistan. The ∑₃₄PCB concentrations ranged from 30.9 to 68.3 ng g^?1 on lipid weight (l.w.) basis. The ∑₈DL-PCB concentrations were ranged from 0.29 to 1.35 ng g^?1 l.w., (mean 6.2 ± 8.7 ng g^?1 l.w.), with toxicity equivalent to polychlorinated dibenzodioxins (PCDDs) ranging from 8.58 × 10^?6 to 0.05 ng TEQ g^?1 l.w. The spatial trend of PCB levels in human milk revealed higher bioaccumulative levels for urban mothers as compared with rural counterparts. The estimated daily intake (EDI) values of DL-PCBs to infants through trans-mammary transfer were considerably higher than tolerable daily intake limits established by WHO (i.e., 1–4 pg TEQ kg^?1 bw) and other globally recognized organizations. Similarly, the hazard quotient values for TEQ ∑₈DL-PCBs (range 1.21 to 79.87) were far above the benchmark value of 1 at all the sampling sites, indicating the high levels of adverse health risks to infants in the region through breast milk consumption. The ∑₃₄PCB levels were found to be negatively correlated with mother’ age (r = ?0.31; p = 0.02), parity (r = ? 0.85; p = 0.001), and infant’ birth weight (r = ? 0.73; p = 0.01). The present study suggests undertaking comprehensive public health risk assessment studies and firm regulatory measures to safeguard human health risks.

     

Comparison of mechanical pretreatment methods for the enhancement of anaerobic digestion of pulp and paper waste activated sludge

The conventional anaerobic digestion process, requiring long solids retention times (SRTs) to digest solids, is currently viewed as impractical for the pulp and paper industry because of high capital costs associated with the construction of new digesters. Recent developments in sludge solubilization technology could be promising in reducing digester size, which also allows for the potential use of decommissioned tanks, both of which can reduce the capital cost. Three pretreatment technologies for use with anaerobic digestion were tested on laboratory-scale to investigate their feasibility. The SRTs in all three digesters systematically decreased from 20 to 3 days. The reference digester was fed waste activated sludge (WAS) to serve as the control at the same SRTs. The other digesters were fed WAS that had been preconditioned using mechanical shearing, sonication, or high-pressure homogenization technology. Anaerobic digestion with high-pressure homogenization produced as much methane at 3-day mean SRT as that from the reference digester operated at 20-day SRT. Therefore, a new digester can theoretically be 85% smaller than a conventional digester. An added benefit of WAS to methane conversion is the recovery of nutrients nitrogen and phosphorus.     

Control strategy of shortcut nitrification

Shortcut nitrification for ammonium-rich wastewater is energy-saving and cost-effective procedure that has become one of the hotspots in the field of biological denitrogenation. An orthogonal experiment was performed to study the combined effects of operational parameters on the performance of internal-loop airlift bioreactor for shortcut nitrification. The optimum operational parameters for the shortcut nitrification were fotmd as temperature 35 ℃, pH 8.0, dissolved oxygen concentration 1.0 mg/L, ammonium concentration 4 mmol/L and HRT 16 h, which have different influence on the performance of shortcut nitrification reactor. The pH, temperature and dissolved oxygen concentration have significant bearing on the process. The results showed that the shortcut nitrification reactor could be successfully started up within 42 d, and the reactor performance is steady with minimum NO2-/NOx- of 85.2%, maximum 93.4% and average value of 91.4% in effluent. Based on the analysis of experimental data, a new control strategy named “priority ＋ combination” for shortcut nitrification was suggested. Through this strategy, the startup and operation of shortcut nitrification for ammonium-rich sludge digester liquids were optimized. The control strategy works well to keep the reactor operation in steady state and in achieving high-efficiency for shortcut nitrification.     

Influence of metallic species for efficient photocatalytic water disinfection: bactericidal mechanism of in vitro results using docking simulation

Environmental Science and Pollution Research - TiO2-based heterogeneous photocatalysis systems have been reported with remarkable efficiency to decontaminate and mineralize a range of pollutants...     

Mercury chloride toxicity in human erythrocytes: enhanced generation of ROS and RNS,hemoglobin oxidation,impaired antioxidant power,and inhibition of plasma membrane redox system

Environmental Science and Pollution Research - Mercury is among the most toxic heavy metals and a widespread environmental pollutant. Mercury chloride (HgCl2) is an inorganic compound of mercury...     

Differential toxicity of cadmium to mustard (Brassica juncia L.) genotypes under higher metal levels

Cadmium application inhibited various growth and biochemical parameters in seedlings of five cultivars of Brassicajuncia L. with different magnitude at lower Cd supply, however, at higher metal applications the variation in Cd toxicity ranged with minor differences. The seedling vigour index (SVI) was inhibited more severely in Gangotri (62.25% over control) and least in Pusa Jai Kisan (8.95%) at 1.0 mM CdCI2. The SVI of all five mustard cultivars, however, severely inhibited (84.29-91.80%) at 5.0 mM Cd. The root and shoot elongation in 7 days old seedlings were inhibited by 32.39-40.38 and 11.83-56.40% respectively at 1.0 mM CdCI2. whereas the varietal differences in root and shoot elongation were 76.71-82.47 and 71.57-78.91 respectively at 5.0 mM CdCI2 The genotypic differences at lower Cd level were more pronounced in shoot elongation than that in the root elongation. The dry weight and moisture content of the seedlings, however, does notshow much varietal differences even at lower Cd level, though the Cd toxicity increased at higher level of Cd application. The metal tolerance index (MTI) and % phytotoxicity of 3 days old seedlings ranged between 43.30-98.37 and 1.63-56.70% respectively at 1.0 mM CdCI2 for different mustard genotypes, whereas at 5.0 mM CdCI2 these factors ranged between 12.26-20.92 and 80.08-87.74% respectively. The varietal differences of MTI and % phytotoxicity was, however, less pronounced at all the metal levels when the seedling attained an age of 7 days. Asimilar trend of genotypic variation was noticed in Cd accumulation in the seedlings at lower and higher levels of Cd supply to the seedlings.Amongst some biochemical parameters e.g. photosynthetic pigments, carbohydrates and proteins in the leaves, the photosynthetic pigments i.e. chlorophylls and carotenoids were decreased more drastically. The carbohydrate content of leaves, however, was the least affected component. Our data indicate that the differential toxicity of cadmium to Indian mustard genotypes was dependent on the level of contamination and growth phases.     

Anammox in a UASB reactor treating saline wastewater

The feasibility of an anammox (anaerobic ammonium oxidation) UASB (upflow anaerobic sludge blanket) bioreactor to treat ammonium-rich brines was investigated in batch and continuous-flow experiments. The evidence from batch tests indicated that the anammox activity was significantly inhibited under highly saline conditions while the inhibition was reversible. Saline shock loading of 30 g NaCl l⁻¹ caused a 67.5% decrease in specific anammox activity (SAA) compared to reference biomass (not exposed to salt). However, the acclimatized biomass displayed a SAA value just 45.1% lower than that of the reference biomass. When transferred from brine to freshwater, the salt-exposed biomass resumed its activity by 43.1%. Subsequent to appropriate acclimatization, careful manipulation nitrite concentration, nitrogen loading rate (NLR), and other operational parameters for 77 days, the results of continuous-flow experiment revealed that under the salinity of 30 g NaCl l⁻¹ the reactor performed well and the substrate removal capacity (nitrogen removal rate, NRR, of 448 ± 15 mgl⁻¹ d⁻¹) was comparable to the condition of freshwater (NRR of 464 ± 13 mgl⁻¹ d⁻¹). However, the anammox UASB bioreactor was prone to malfunction under transient operating conditions.     

Insights into conventional and recent technologies for arsenic bioremediation: A systematic review

Environmental Science and Pollution Research - Arsenic (As) bioremediation has been an economical and sustainable approach, being practiced widely under several As-contaminated environments....