Time filter

Source Type

Banerjee D.,University of Burdwan | Das P.P.,Asansol Mines Board of Health | Fouzdar A.,West Bengal Pollution Control Board
Journal of Urban Health

Results from studies involving exposure to road traffic noise and risk of hypertension are diverse and have seldom reached statistical significance. This study was designed with the aim of investigating whether there is any association between road traffic noise and prevalence of hypertension in an urban adult population. Similar studies have never been reported from India. A cross-sectional study was performed on 909 adults (533 female and 376 male) aged 18–80 years residing in close proximity to roadways in Asansol City. Time-weighted equivalent noise level (Lden) was estimated using a standard modeling platform. Odds for hypertension in relation to traffic noise exposure were estimated by univariate and multifactorial logistic regression. The adjusted odds ratio (OR) for self-reported hypertension was 1.99 (95 % confidence interval (CI) 1.66–2.39) per 5 dB(A) increase of Lden (range 55.1–77.9). A gender-related risk difference was observed among the male (OR 1.81 (1.42–2.31)) and female (OR 2.18 (1.66–2.88)) respondents. For increase in 9 years of age, the odds of hypertension risk increased by 60 % (OR 1.66 (1.43–1.91) among those exposed above Lden 60 dB(A). Vulnerable subgroups were female aged 35–54 years and male aged 45–54 years. The study suggests that a threshold exposure to road traffic noise at Lden > 65 dB(A) for men and Lden > 60 dB(A) in women may be associated with the occurrence of hypertension. © 2014, The New York Academy of Medicine. Source

Banerjee D.,University of Burdwan | Das P.P.,Asansol Mines Board of Health | Foujdar A.,West Bengal Pollution Control Board
Environmental Monitoring and Assessment

There is an established evidence that exposure to high levels of road traffic noise is associated with elevated risk of coronary heart disease (CHD). The results however have been heterogeneous and mostly inconclusive. The present investigation aimed to examine this association in adult subjects, with a secondary aim of identifying potentially vulnerable sub-populations. Similar studies have never been reported from Indian population. For exposure assessment, the time-weighted road traffic noise indicator, L den, was used as a continuous and categorical predictor. A cross-sectional study was designed, and sociodemographic and lifestyle- and health-related characteristics were recorded for 909 (533 females and 376 males) subjects aged 18-80 years. The respondents living in areas with L den<60 dB(A) were designated as the reference group. Odds for self-reported CHD in relation to traffic noise exposure were estimated by univariate and multifactorial logistic regression with adjustments for potential confounders and effect modifiers. The adjusted odds ratio (OR) for self-reported CHD was 1.72 (95 % CI 1.36-2.19) per 5 dB(A) increase of L den (range 55-80 dB(A)). A gender-related risk difference was observed among male (OR 1.47 (1.07-2.02)) and female (OR 1.83 (1.27-2.65)) respondents. A stronger effect for subjects in the age group 55-64 years old was found, with age, residence period, body mass index, and self-reported stress being significant confounders. This study suggests epidemiological evidence that exposure to road traffic noise of L den>65 dB(A) may be associated with occurrence of CHD in adult subjects. A trend was observed indicating increasing risk with higher exposure levels. The study results are also suggestive of higher risk of outcome among those with other chronic ailments (diabetes, pulmonary, or renal issues) and residing in the same location in excess of 15 years. Orientation of bedroom windows was identified as a significant effect modifier. © 2013 Springer Science+Business Media Dordrecht. Source

Chatterjee A.,Bose Institute of India | Sarkar C.,Bose Institute of India | Adak A.,Bose Institute of India | Mukherjee U.,West Bengal Pollution Control Board | And 2 more authors.
Aerosol and Air Quality Research

The effects of fireworks on air quality was assessed from the ambient concentrations of PM10, water soluble ionic species, metals and SO2 over Kolkata metropolis, India during Diwali festival in November 2010. PM10 concentrations on Diwali night were found to be ~5 times higher than the normal day night-time average. The increase in night-time concentrations of the metals on Diwali night spanned over a wide range (Al, Zn, Pb and Cd showed 5-12 times increases, Cu, Fe and Mn showed 25-40 times and Co and V showed 70-80 times) compared to normal night-time concentrations. The water soluble ionic species showed 1.5-6 times higher concentrations on Diwali night than on normal days. The most significant increases were found for K+, Ca2+, Mg2+ and SO4 2-. The diurnal variations in PM10 and SO2 were also studied at one of the sites, and the results showed that their maximum concentrations were on Diwali night between 8 P.M.-3 A.M., indicating maximum firework activities during this period. PM10 and SO2 concentrations increased by ~5 times compared to those on normal days during this period at this site. The extensive use of firecrackers during Diwali festival thus leads to significant increases in these air pollutants, and since they are associated with serious, adverse health impacts, the use of fireworks during in this kind of festival in a highly populated city, like Kolkata, India, needs to be controlled. © Taiwan Association for Aerosol Research. Source

Das D.,West Bengal Pollution Control Board | Das D.,City Center | Sengupta P.P.,National Institute of Technology Durgapur
Environment, Development and Sustainability

The developing countries i.e., the non-Annex-I countries (parties to the Kyoto Protocol but not responsible to any reduction target yet) in the Kyoto Protocol whose economies are in transition are also allowed to reduce GHG emissions. Among these, the countries that have accepted the Kyoto Protocol may be benefited from CDM projects to promote sustainable development. The developed countries i.e., the Annex-I countries (that have signed the Kyoto Protocol & are responsible to have specific GHG emission reduction target) or the investing countries, in return, have privilege to purchase CER credits (in units equivalent to one tonne of CO2 gas emission reduction) to meet the emission target as specified in the Kyoto Protocol. The key step in understanding about CDM is to grasp the concept of "baseline" and "additionality". The "Baseline" is the emissions level that would have existed if a CDM project had not happened. The feature of an approved CDM project is that the planned reductions would not occur without the additional incentive provided by emission reduction credits; this concept is known as "Additionality". According to environmental additionality concept, baseline emission minus project emission is equal to emissions reduction. "Investment Additionality," ultimately rejected during negotiation of the "Marrakech Accords" and "Financial Additionality," are the two important concepts. The concept of trading of CER matches to the idea of Pigovian tax (equal to the negative externality and which is considered one of the "traditional" means of bringing a modicum of market forces) in Economics, making pollution more costly to the polluter, as the polluters have negative cost since they save money by polluting; hence, there are supposed negative externalities associated with the market activity. Economic theory predicts that in an economy where the cost of reaching mutual agreement between parties is high and where pollution is diffuse, Pigovian tax will be an efficient way to promote the public interest and will lead to an improvement of the quality of life measured by the Genuine Progress Indicator and other human economic indicators, as well as higher gross domestic product growth. We can seek a level of pollution such that the marginal savings (MS) to one polluting unit from pollution (-MC) is equal to marginal damage (MD) from pollution over the entire population, since pollution is a public bad i.e., MS (x*) = ∑MDi (x*) where ∑Di (x) is the total damage. Though the responsibility of reduction in emission does not lie on the non-Annex-I countries, still effort of maintaining global emission balance can be expected equally from developed and developing countries. The responsibilities of Kyoto Protocol are (a) to reduce global GHG emissions, (b) to bring about sustainable development in the developing countries lie on above two groups since its effect on February 16, 2005. Different polluters have different costs of pollution control. The least costly way of controlling pollution from various sources that reflects different costs of pollution control making the set of environmental regulations to achieve the emission target at the lowest cost makes the regulation cost-effective. Though efficiency is not attainable for many regulations, cost-effectiveness is attainable. © 2011 Springer Science+Business Media B.V. Source

Riaz N.,Petronas University of Technology | Riaz N.,COMSATS Institute of Information Technology | Chong F.K.,Petronas University of Technology | Man Z.B.,Petronas University of Technology | And 3 more authors.
Industrial and Engineering Chemistry Research

Bimetallic Cu-Ni/TiO2 photocatalysts were prepared at different temperatures with varying Cu:Ni mass compositions. The photocatalysts were further calcined at selected temperatures. Characterization procedures were carried out on the photocatalysts to understand the correlation between the photocatalytic activity and the physicochemical and morphological properties. Results from the XRD, FESEM-EDX mapping, and HRTEM analyses were in favor of the metal particles existing in the form of well-dispersed oxides on TiO 2 surface. The surface area of the photocatalysts was almost similar to the bare TiO2 ∼43 m2 g-1 except for 1Cu:9Ni-200-b observed with a higher surface area (53.8 m2 g -1) as compared to other photocatalysts. The photocatalyst performance of the bimetallic system is promising as compared to bare TiO 2 and the monometallic photocatalysts. Results for photodegradation studies showed that 1:9 Cu:Ni mass composition was observed with 100% Orange II removal as compared to other Cu:Ni mass compositions. The 1Cu:9Ni-200-a photocatalyst prepared at lower temperature (8-10 C) displayed 100% Orange II decolorization as compared to 1Cu:9Ni-200-b (prepared at higher temperature of 25 C) with 65.1% dye removal. Although the results from UV-vis spectra showed the disappearance of the visible band (indicating 100% Orange II removal), TOC analysis indicated the presence of organic compounds derived from the dye degradation process. Therefore, longer irradiation time is required to break the chromophore groups in the degradation intermediates to obtain 100% TOC removal. © 2013 American Chemical Society. Source

Discover hidden collaborations