Health impact and noise exposure assessment in the cricket bat industry of Kashmir,India

Aim. The aim of the present study was to identify and evaluate predominant noise sources in the cricket bat industry of Kashmir, India. Methods. Sound levels were measured at operator’s ear level in the working zone of the workers of seven cricket bat factories. The impact assessment was made through personal interviews with each worker separately during their period of rest. Results. On average, 62.5% of the workers reported difficulty in hearing and 24.1% of the workers have become patients for hypertension. Only 58.1% of the workers complained of headache due to high noise level. Conclusions. The workers engaged in the cricket bat industry of Kashmir are exposed to high noise levels. It is suggested that personal protective equipment like ear plugs and ear muffs be used by these workers as a protection against this hazard.     

污水厂强化生物硝化和除磷的研究及运行策略

针对城镇污水厂运行过程中出现的问题(进水水质复杂、pH超标,造成NH3-N去除效率极低及某A/O工艺污水厂出水TP波动),进行了强化生物硝化和除磷的试验研究,得出了污水厂的运行控制策略,同时分析了A2/O工艺的运行模式对生物除磷的影响。     

Vertical and horizontal distributions of microbial abundances and enzymatic activities in propylene-glycol-affected soils

The natural microbial activity in the unsaturated soil is vital for protecting groundwater in areas where high loads of biodegradable contaminants are supplied to the surface, which usually is the case for airports using aircraft de-icing fluids (ADF) in the cold season. Horizontal and vertical distributions of microbial abundance were assessed along the western runway of Oslo Airport (Gardermoen, Norway) to monitor the effect of ADF dispersion with special reference to the component with the highest chemical oxygen demand (COD), propylene glycol (PG). Microbial abundance was evaluated by several biondicators: colony-forming units (CFU) of some physiological groups (aerobic and anaerobic heterotrophs and microscopic fungi), most probable numbers (MPN) of PG degraders, selected catabolic enzymatic activities (fluorescein diacetate (FDA) hydrolase, dehydrogenase, and β-glucosidase). High correlations were found between the enzymatic activities and microbial counts in vertical soil profiles. All microbial abundance indicators showed a steep drop in the first meter of soil depth. The vertical distribution of microbial abundance can be correlated by a decreasing exponential function of depth. The horizontal trend of microbial abundance (evaluated as total aerobic CFU, MPN of PG-degraders, and FDA hydrolase activity) assessed in the surface soil at an increasing distance from the runway is correlated negatively with the PG and COD loads, suggesting the relevance of other chemicals in the modulation of microbial growth. The possible role of potassium formate, component of runway de-icers, has been tested in the laboratory by using mixed cultures of Pseudomonas spp., obtained by enrichment with a selective PG medium from soil samples taken at the most contaminated area near the runway. The inhibitory effect of formate on the growth of PG degraders is proven by the reduction of biomass yield on PG in the presence of formate.     

Bootstrap confidence intervals for adaptive cluster sampling design based on Horvitz–Thompson type estimators

Perez and Pontius (J Stat Comput Simul 76:755–764, 2006) introduced several bootstrap methods under adaptive cluster sampling using a Horvitz–Thompson type estimator. Using a simulation study, they showed that their proposed methods provide confidence intervals with highly understated coverage rates. In this article, we first show that their bootstrap methods provide biased bootstrap estimates. We then define two bootstrap methods, based on the method of Gross (Proceeding of the survey research methods section. American Statistical Association, Alexandria, VA, pp 181–184, 1980) and Bootstrap With Replacement, that provide unbiased bootstrap estimates of the population mean with bootstrap variances matching the corresponding unbiased variance estimator. Using a simulation study, we show that the bootstrap confidence intervals based on our proposed methods have better performance than those based on available bootstrap methods, in the sense of having coverage proportion closer to the nominal coverage level. We also compare the proposed intervals to empirical likelihood based intervals in small samples.     

Examination of model predictions at different horizontal grid resolutions

While fluctuations in meteorological and air quality variables occur on a continuum of spatial scales, the horizontal grid spacing of coupled meteorological and photochemical models sets a lower limit on the spatial scales that they can resolve. However, both computational costs and data requirements increase significantly with increasing grid resolution. Therefore, it is important to examine, for any given application, whether the expected benefit of increased grid resolution justifies the extra costs. In this study, we examine temperature and ozone observations and model predictions for three high ozone episodes that occurred over the northeastern United States during the summer of 1995. In the first set of simulations, the meteorological model RAMS4a was run with three two-way nested grids of 108/36/12 km grid spacing covering the United States and the photochemical model UAM-V was run with two grids of 36/12 km grid spacing covering the eastern United States. In the second set of simulations, RAMS4a was run with four two-way nested grids of 108/36/12/4 km grid spacing and UAM-V was run with three grids of 36/12/4 km grid spacing with the finest resolution covering the northeastern United States. Our analysis focuses on the comparison of model predictions for the finest grid domain of the simulations, namely, the region overlapping the 12 km and 4 km domains. A comparison of 12 km versus 4 km fields shows that the increased grid resolution leads to finer texture in the model predictions; however, comparisons of model predictions with observations do not reveal the expected improvement in the predictions. While high-resolution modeling has scientific merit and potential uses, the currently available monitoring networks, in conjunction with the scarceness of highly resolved spatial input data and the limitations of model formulation, do not allow confirmation of the expected superiority of the high-resolution model predictions.The U.S. Governments right to retain a non-exclusive royalty-free licence in and to any copyright is acknowledged.     

Physico-Chemical Quality of Drinking Water in Rohtas District of Bihar

Water Quality Survey of Rohtas district of Bihar was conducted. Samples were collected from differentsources and analysed. 209 samples were collectedfrom 196 villages. Results of water quality surveyidentified the problem areas in respect of high iron,manganese, fluoride, nitrate and brackishness of water in the district.     

Measurement of particulate phase polycyclic aromatic hydrocarbon (PAHs) around a petroleum refinery

A study on concentrations of ambient particulates viz. total suspended particulate matters (TSP), respirable suspended particulate matter (RSPM) and polycyclic aromatic hydrocarbons (PAH) were carried out at six sites around the Asia’s largest, 12 MMTPA, petroleum refinery in west coast of India. PAH concentrations are correlated with each other in these sites, suggesting that they have related sources and sinks. The present article discusses the monitoring aspects such as sample collection, pretreatment and analytical methods and compares the monitored levels for assessing the source receptor distribution pattern. The main sources of RSPM and PAHs in urban air are automobile exhaust (CPCB, Polycyclic aromatic hydrocarbons (PAHs) in air and their effects on human health. “”, 2003; Manuel et al., Environmental Science and Technology, 13: 227–231, 2004) and industrial emissions like petroleum refinery (Vo-Dinh, Chemical analysis of polycyclic aromatic hydrocarbons, Wiley: New York, 1989; Wagrowaski and Hites, Environmental Science and Technology, 31: 279–282, 1997). Polycyclic aromatic hydrocarbons (PAH) are ubiquitous constituents of urban airborne particulate mostly generated by anthropogenic activities (Li et al., Environmental Science and Technology, 37:1958–2965, 2003; Thorsen et al., Environmental Science and Technology, 38: 2029–2037, 2004; Ohura et al., Environmental Science and Technology, 32: 450–455, 2004) and some of them are of major health concern mainly due to their well-known carcinogenic and mutagenic properties (Soclo et al., Marine Pollution Bulletin, 40: 387–396, 2000; Chen et al., Environment International, 28: 659–668, 2003; Larsen and Baker, Environmental Science and Technology, 32: 450–455, 2003). Limited information is available on PAHs contributions from refineries to ambient air. Hence this study would not only create a database but also provide necessary inputs towards dose-response relationship for fixing standards. Also, since it acts as precursor to green house gas, the data would be useful for climate change assessments. The objective of this article is to find out the concentration of PAHs in particulate matter around petroleum refinery and compare with their concentrations in major Indian urban centers.     

Soil respiration,labile carbon pools,and enzyme activities as affected by tillage practices in a tropical rice–maize–cowpea cropping system

In order to identify the viable option of tillage practices in rice–maize–cowpea cropping system that could cut down soil carbon dioxide (CO₂) emission, sustain grain yield, and maintain better soil quality in tropical low land rice ecology soil respiration in terms of CO₂ emission, labile carbon (C) pools, water-stable aggregate C fractions, and enzymatic activities were investigated in a sandy clay loam soil. Soil respiration is the major pathway of gaseous C efflux from terrestrial systems and acts as an important index of ecosystem functioning. The CO₂–C emissions were quantified in between plants and rows throughout the year in rice–maize–cowpea cropping sequence both under conventional tillage (CT) and minimum tillage (MT) practices along with soil moisture and temperature. The CO₂–C emissions, as a whole, were 24 % higher in between plants than in rows, and were in the range of 23.4–78.1, 37.1–128.1, and 28.6–101.2 mg m^?2 h^?1 under CT and 10.7–60.3, 17.3–99.1, and 17.2–79.1 mg m^?2 h^?1 under MT in rice, maize, and cowpea, respectively. The CO₂–C emission was found highest under maize (44 %) followed by rice (33 %) and cowpea (23 %) irrespective of CT and MT practices. In CT system, the CO₂–C emission increased significantly by 37.1 % with respect to MT on cumulative annual basis including fallow. The CO₂–C emission per unit yield was at par in rice and cowpea signifying the beneficial effect of MT in maintaining soil quality and reduction of CO₂ emission. The microbial biomass C (MBC), readily mineralizable C (RMC), water-soluble C (WSC), and permanganate-oxidizable C (PMOC) were 19.4, 20.4, 39.5, and 15.1 % higher under MT than CT. The C contents in soil aggregate fraction were significantly higher in MT than CT. Soil enzymatic activities like, dehydrogenase, fluorescein diacetate, and β-glucosidase were significantly higher by 13.8, 15.4, and 27.4 % under MT compared to CT. The soil labile C pools, enzymatic activities, and heterotrophic microbial populations were in the order of maize?>?cowpea?>?rice, irrespective of the tillage treatments. Environmental sustainability point of view, minimum tillage practices in rice–maize–cowpea cropping system in tropical low land soil could be adopted to minimize CO₂–C emission, sustain yield, and maintain soil health.     

Detection of toxic heavy metals and pesticide residue in herbal plants which are commonly used in the herbal formulations

Herbal formulations are getting popular throughout the world and commercialized extensively for various medicinal properties. WHO has emphasized the need for quality assurance of herbal products, including testing of heavy metals and pesticides residues. In view of WHO guidelines, single herbal drugs used in herbal formulations were collected from local market, for testing heavy metals and persistent pesticides residue. Therefore, in the present case, we have examined few local samples of certain herbs viz. Emblica officinalis, Terminalia chebula, Terminalia belerica, and Withania somnifera. The present studies were selected for estimation of four heavy metals namely Arsenic, Cadmium, Lead, and Mercury. Apart from these, pesticide residue Viz. Organochlorine pesticides, Organophosphorus pesticides, and Pyrethroids were analyzed in the four samples of single crude drugs. Heavy metals and pesticide residue were found below detection limits in all the samples.