Investigation of carbonyl compounds in air from various industrial emission sources

The emission concentrations of carbonyl compounds in air were quantified from a total of 195 man-made source units within 77 individual companies at a large industrial complex in Korea. The measurement data were evaluated both by absolute magnitude of concentration and by their relative contribution to malodor formation such as malodor degree (MD) derived from empirical formula. It was found that formaldehyde exhibited the highest mean concentration of 323ppb with a median value of 28.2ppb, while butyraldehyde recorded the highest contribution to odor formation with an MD value of 3.5 (186 (mean) and 9.8ppb (median)). The relative intensity of carbonyl emission, when compared by the sum of MD, showed the highest source strength from the food and beverage (industry sector) and scrubber (source unit). A comprehensive evaluation of the carbonyl data from diverse industrial facilities thus allowed us to describe the fundamental patterns of their emission.     

Determination of Path Coefficients and Its Application in Road Traffic Noise Annoyance – a Theoretical Approach

This paper elucidates the basic approach of determining the path coefficients and its significance in the road traffic noise annoyance. Path model not only outline the direct effect of the traffic noise on the nearby residents but also indicate the indirect effect via other variables. In this study seven variables were considered for determining road traffic noise annoyance. However the same would be equally applicable for other situations like aircraft noise, rail noise, and industry noise with the different variables. At the outset a priori path model was designed and then on the basis of the partial regression coefficient values for the different paths, the revised path model was developed. The standardized partial regression coefficients known as path coefficients, determine the strength of the linkage among variables. Some of the paths in the model were not statistically significant. Revised path models were developed by deleting the insignificant paths whose values were found above 5% level. In the revised path model, thus the direct and indirect effect due to a particular variable causing the road traffic noise annoyance could be observed.     

Relationship of methyl mercury accumulation with lipid and weight in two river cat fish species, Wallagoo attu and Mystus aor, from West Bengal, India

This study focuses on mercury (Hg) bioaccumulation in Indian cat fish, Wallagoo attu and Mystus aor, from different rivers. Methyl mercury (MeHg) concentrations were determined in muscle tissue of two different parts, ventral and dorsal part, of each species and the levels of organic mercury were co-related with lipid content of each part. The MeHg concentrations increased in a linear fashion with both weight and age for these river species. The average concentration of MeHg was found to be 0.93?±?0.60 and 1.26?±?0.62 μg Hg g^?1 (expressed in wet weight basis) for ventral and dorsal parts, respectively in W. attu and this was above the 0.25 μg Hg g^?1 of wet weight, the limit set by the Prevention of Food Adulteration Act for the maximum level for consumption of fish exposed to mercury pollution. In M. Aor the concentration of MeHg was not above the standard limit but threatening, it was 0.22?±?0.07 and 0.23?±?0.08 μg Hg g^?1 (expressed in wet weight basis) in dorsal and ventral parts, respectively.     

Effect of chlorpyrifos on microbial biomass and activities in tropical clay loam soil

Clay loam soil from agricultural field of Gangetic alluvial zone of West Bengal was investigated to evaluate the effect of chlorpyrifos application at field rate (0.5 mg kg^???1 soil) and 100 times of the field rate (50 mg kg^???1 soil) on soil microbial variables under laboratory conditions. Acetone-induced stress on soil microorganisms was evident in the initial stages in terms of microbial biomass carbon (MBC) content in soil and basal soil respiration (BSR) in control soil samples which received acetone only as compared to control soil without acetone. The soil MBC content increased significantly by application of chlorpyrifos. The BSR and the fluorescein diacetate hydrolysing activity (FDHA) were not adversely affected by chlorpyrifos at field rate, whilst the chemical at higher dosage significantly decreased the metabolic activities of soil microbes in terms of BSR and FDHA.     

Diversity of soil fungi in North 24 Parganas and their antagonistic potential against Leucinodes orbonalis Guen. (Shoot and fruit borer of brinjal)

Soil samples were collected from agricultural fields and gardens in North 24 Parganas, West Bengal, and fungi species were isolated from them. Thirty-one fungal species were isolated with 19 found in agricultural soil and 28 in garden soil. Twenty-eight out of 31 were identified using cultural and microscopic characters, and three were unidentified. The diversity of isolated fungi was calculated by Simpson’s diversity index. The garden soil possessed more fungal colonies (750) than agricultural soil (477). In agricultural soil, the dominant fungi were Aspergillus niger, Rhizopus oryzae, and Penicillium expansum, and the dominant fungi of garden soil were A. niger and Fusarium moniliforme. Simpson’s diversity index indicated that garden soil had more fungal diversity (0.939) than agricultural soil (0.896). The entomopathogenic capacity of the isolated fungi was tested against the brinjal shoot and fruit borer (Leucinodes orbonalis Guen) which is the major insect pest of brinjal. The isolated fungi were screened against larva of L. orbonalis for their entomopathogenic potential. Beauveria bassiana, A. niger, and P. expansum showed appreciable antagonism to L. orbonalis, and their lethal doses with 50 % mortality (LD₅₀s) were 4.0?×?10⁷, 9.06?×?10⁷, and 1.50?×?10⁸ spore/mL, respectively, and their times taken to reach 50 % mortality (LT₅₀s) were 9.77, 10.56, and 10.60 days, respectively. This work suggests the restriction of chemical pesticide application in agricultural fields to increase fungal diversity. The entomopathogenic efficacy of B. bassiana could be used in agricultural fields to increase fugal diversity and protect the brinjal crop.     

Epibrassinolide ameliorates Cr (VI) stress via influencing the levels of indole-3-acetic acid, abscisic acid, polyamines and antioxidant system of radish seedlings

The present investigation determined the effects of epibrassinolide (EBL) on the levels of indole-3-acetic acid (IAA), abscisic acid (ABA), and polyamine (PA) and antioxidant potential of 7-d old Raphanus sativus L. cv. ‘Pusa chetki’ seedlings grown under Cr (VI) metal stress. Reduced titers of free (0.767 μg g⁻¹ FW) and bound (0.545 μg g⁻¹ FW) IAA in Cr (VI) stressed seedlings were observed over untreated control. Supplementations of EBL to Cr (VI) stressed seedlings were able to enhance both free (2.14-5.68 μg g⁻¹ FW) and bound IAA (2.45-7.78 μg g⁻¹ FW) concentrations in comparison to Cr (VI) metal treatment alone. Significant rise in free (13.49 μg g⁻¹ FW) and bound (12.17 μg g⁻¹ FW) ABA contents were noticed for Cr (VI) stressed seedlings when compared to untreated control. No significant increase in ABA contents were recorded for Cr (VI) stressed seedlings upon supplementation with EBL over Cr (VI) treatment alone. A significant increase in Put (18.40 μg g⁻¹ FW) and Cad (9.08 μg g⁻¹ FW) contents were found for 10⁻⁹ M EBL plus Cr (VI) metal treatments when compared to Cr (VI) treatment alone. Spermidine (Spd) contents were found to decline significantly for EBL treatment alone or when supplemented with Cr (VI) treatments over untreated controls and Cr (VI) treatment alone. Antioxidant levels were found to enhance, with glutathione (57.98 mg g⁻¹ FW), proline (4.97 mg g⁻¹ FW), glycinebetaine (39.01 μmol mL⁻¹), ascorbic acid (3.17 mg g⁻¹ FW) and phytochelatins (65.69 μmol g⁻¹ FW) contents noted for EBL supplemented to Cr (VI) metal solution over Cr (VI) treatment alone. Reduced activities of guaiacol peroxidase (0.391 U mg⁻¹ protein) and catalase (0.221 U mg⁻¹ protein) and enhanced activities of glutathione reductase (7.14 U mg⁻¹ protein), superoxide dismutase (15.20 U mg⁻¹ protein) and ascorbate peroxidase (4.31 U mg⁻¹ protein) were observed in seedlings treated with EBL plus Cr (VI) over Cr metal treatment alone. Reduced MDA (2.55 μmol g⁻¹ FW) and H₂O₂ (33.24 μmol g⁻¹ FW) contents were recorded for 10⁻⁹ M EBL supplemented to Cr (VI) stress over Cr (VI) treatment alone. Enhancement in free radical scavenging potential as indicated by higher values of 1,1-diphenylpicrylhydrazyl, deoxyribose and reducing power activity assays, and increased levels of phenols and soluble sugars also showed significant influence of EBL in alleviating Cr (VI) stress in radish seedlings.     

Toxicity assessment of textile effluents treated by advanced oxidative process (UV/TiO2 and UV/TiO2/H2O2) in the species Artemia salina L.

Textile industry wastes raise a great concern due to their strong coloration and toxicity. The objective of the present work was to characterize the degradation and mineralization of textile effluents by advanced oxidative processes using either TiO₂ or TiO₂/H₂O₂ and to monitor the toxicity of the products formed during 6-h irradiation in relation to that of the in natura effluent. The results demonstrated that the TiO₂/H₂O₂ association was more efficient in the mineralization of textile effluents than TiO₂, with high mineralized ion concentrations (NH ₄ ⁺ , NO ₃ ^? , and SO ₄ ^2? ) and significantly decreased organic matter ratios (represented by the chemical oxygen demand and total organic carbon). The toxicity of the degradation products after 4-h irradiation to Artemia salina L. was not significant (below 10 %). However, the TiO₂/H₂O₂ association produced more toxicity under irradiation than the TiO₂ system, which was attributed to the increased presence of oxidants in the first group. Comparatively, the photogenerated products of both TiO₂ and the TiO₂/H₂O₂ association were less toxic than the in natura effluent.     

Suitability of different erosivity models used in RUSLE2 for the South West Indian region

RUSLE2 is the most used soil erosion model in practice. The rainfall-erosivity factor (R) is one of the six factors that is taken into consideration while estimating soil loss at a hill slope profile. R is determined using rainfall data collected from any region making use of basic rainstorm kinetic energy versus rainfall intensity relationships, which are variable for different geographic regions. Indian researchers used a specific erosivity model for building an iso-erosivity map for India. Many other erosivity models around the world are now available. However, it is not clear whether one can replace RUSLE2 recommended model by the ones derived in other geographic regions for using in Indian soil erosion studies. This has been examined here on south-western Indian data. Various models derived in diverse places were analyzed and compared with the RUSLE2 recommended relationship; and found that, a few could very well replace the usual RUSLE2 recommended expression.     

Variability of total ozone over India and its adjoining regions during 1997–2008

Total Ozone Concentration (TOC) data over nineteen stations around India (fifteen stations) and its adjoining regions (three stations in Pakistan and one station in Bangladesh) are investigated in the present analysis. The overpass satellite data for these nineteen stations, distributed in the latitude range from 8.48°N to 35.83°N and altitude range from 6 m to 2718 m are available from FTP Site. TOC data pertaining to the last twelve years from 1997 to 2008 were obtained from two different instruments: Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI) on Earth Probe and AURA satellites respectively. The analysis is divided into two phases, each of six years duration; from 1997 to 2002 and from 2003 to 2008. Seasonal average values of TOC are calculated for the two phases and compared to study the spatial distribution (latitude, longitude and station altitude) and the trends of TOC variation. In general a decreasing tendency in ozone concentration was found everywhere. The average yearly rate of the TOC decrease was ?0.363 DU over the entire region during the period 1997–2008. The trends in the TOC distribution and its decrease with latitude were found parabolic, with a deep near 14.7°N and 12.1°N for the two phases respectively. The decrease was maximum at lower latitude (?1.87%) and minimum (?0.25%) at higher latitude. Weak oscillatory trends in the TOC distribution and its decrease with longitude were found. A deep in the longitudinal variation was observed in each phase, at 77.4°E during 1997–2002 and at 78.2°E during 2003–2008. The minimum centre of the ozone distribution is therefore shifted from 14.7°N, 77.4°E to 12.1°N, 78.2°E over the last twelve years, and in general a meridional line near 78°E appears to divide symmetrically the TOC distribution over this region. Strong oscillatory trends in the seasonal average of TOC distribution and its decrease with station altitude are observed during the two phases. The inversion of high correlation coefficients between the seasonal average TOC and station altitude in the range 6 m to 2718 m indicate the existence of four transition layers aloft, near 200, 740, 1670, and 2400 m in the lower troposphere. Emission of precursor pollutants together with complex wind pattern around the marine boundary appears to have strong potentials to modulate tropospheric ozone and the observed spatial distribution of TOC may be expected.     

Polycyclic aromatic hydrocarbons in some grounded coffee brands

Potentially toxic 16 priority polycyclic aromatic hydrocarbons (PAHs) were determined in four brands of grounded coffee. Four to 13 PAHs were detected. Concentrations of total PAHs in different brands of coffee samples were in the range of 831.7–1,589.7 μg/kg. Benzo[a]pyrene (2A: probable human carcinogen) was found in Nescafe Premium whereas naphthalene (2B: possible human carcinogen) was found in all the samples of coffee.