Transformation of atmospheric ammonia and acid gases into components of PM<Subscript>2.5</Subscript>: an environmental chamber study

Introduction  

The kinetics of the transformation of ammonia and acid gases into components of PM_2.5 has been examined. The interactions of existing aerosols and meteorology with the transformation mechanism have also been investigated. The specific objective was to discern the kinetics for the gas-to-particle conversion processes where the reactions of NH₃ with H₂SO₄, HNO₃, and HCl take place to form (NH₄)₂SO₄, NH₄NO₃, and NH₄Cl, respectively, in PM_2.5.     

Special issue on sustainable waste treatment and management

Environmental Science and Pollution Research -     

Blood lead level in the children of western Uttar Pradesh,India

The objective of this study was to determine the blood lead levels (blls) of children under an age of 5 years living in western Uttar Pradesh, India. A total of 100 blood samples, 100 drinking water samples, and 21 vegetable samples were assessed for lead contamination. Blood levels in the range of 30–116?µg?L^?1 were observed at Kazipur village. The levels of lead in water samples were reported to be in the range of 0.006–0.095?ppm and identified at up to 9.5 times the stated permissible limit. A significant positive correlation (+0.679) was obtained between blls and water lead levels. All vegetable samples were also contaminated with lead up to 12 times higher than the permissible limit of 2.5?mg?kg^?1 of Prevention of Food Adulteration Act (PFA) 1954. The cottage lead battery industry, industrial effluents, and lead paints were identified as possible factors for lead incidence in the study area. Lead may be associated with increased antisocial activities of the children living in western Uttar Pradesh. Children with elevated blls had poorer nutritional status than those with normal levels, and parents did not know that lead causes health problems. A national population-based study is recommended to determine the prevalence of elevated blls.     

Risk assessment of children's blood lead level in some rural habitations of western Uttar Pradesh,India

The objective of this study was to determine the blood lead level (BLL) of children aged under 5 living in western Uttar Pradesh, India. A total of 100 blood samples, 100 drinking water samples, and 21 vegetable samples were assessed for lead (Pb) contamination. BLL was observed in the range of 3–11.58?µg?dL^?1 with a maximal level of 11.58?±?0.05?µg?dL^?1 in Kazipur village. Lead in water samples was detected in the range of 0.006–0.095?ppm and identified at upto 9.5-fold higher than the stated permissible limit. A significant positive correlation (+0.679) was obtained between BLL and water Pb levels. All vegetable samples were also contaminated with Pb upto 12-fold higher than the permissible limit of 2.5?µg?g^?1 of Prevention of Food Adulteration Act (PFA) 1954. Untreated industrial effluents were identified as the responsible factors for Pb occurrence in the study area. The presence of lead may be associated with the increased antisocial activities of children living in western Uttar Pradesh. Children with elevated BLL had poorer nutritional status than those with background Pb levels. There is an urgent need for a national campaign to monitor the BLL of children in India.     

Bisphenol A and metabolites released by biodegradation of polycarbonate in seawater

This is the first report of bisphenol A release from polycarbonate during biodegradation by marine microorganisms. Bisphenol A is a monomer in polycarbonate and an endocrine disruptor toxic for marine organisms. Biodegradation of polycarbonate is poorly documented. Here, we have tested the possible release of bisphenol A and metabolites during biodegradation of polycarbonate by marine microorganisms. Polycarbonate degradation was carried out in vitro using a mixed marine microbial consortium isolated from the Bay of Bengal, India, 1 year under controlled laboratory conditions. The degradation was monitored by elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), and gas chromatography—mass spectrometry (GC–MS). The organic soluble metabolites were analyzed by high-performance liquid chromatography (HPLC). We found that bisphenol A was released. The amount of bisphenol A released during 1 year is higher than the half-maximal effective concentration (EC₅₀) values reported for marine organisms. We also identified the following bisphenol A metabolites: 4-hydroxyacetophenone, 4-hydroxybenzaldehyde, and 4-hydroxybenzoic acid. Polycarbonate biodegradation was evidenced by gravimetric weight loss and Fourier transform infrared spectroscopy. The reduction of methyl and carbonyl indices suggests oxidation and hydrolysis of the polymer, respectively. 2D NMR showed an aromatic C–C cleavage.     

Measurements of major ion concentration in settled coarse particles and aerosols at a semiarid rural site in India

Deposition rates and deposition velocities of water-soluble ions (F, Cl, NO3, SO4, NH4, Ca, Mg, Na and K) were measured at a rural site (Gopalpura, Agra). Dry deposition samples were collected throughout the year from December 1995 to August 1997, while the aerosol samples were collected only during the winter season of 1996. Surrogate technique was used to collect the dry deposition samples, while aerosol samples were collected on PTFE membrane filter. Deposition velocities (Vd) of SO4 and NO3 are < or = 0.01 m s(-1) while Ca, Mg, Na, K, NH4, F and Cl exhibit greater than 0.01 m s(-1) Equivalent concentration ratios of K/Na, Ca/Na and Mg/Na conform with the corresponding ratios of local soil, indicating the dominant contribution of local sources. Deposition rates are maximum in winter, followed by summer and monsoon. No significant differences are found in dry deposition rates of all ions or in atmospheric concentrations of soil-derived elements with respect to wind direction. However, in aerosols, concentrations of F, Cl, NO3 and SO4 are higher with winds from southwesterly and westerly directions corresponding to pollution sources located in these directions. Deposition data have been used to calculate the critical load of S and N for soil with respect to Triticum vulgaris. The critical load of actual acidity was found to be 622.4 eq ha(-1) year(-1) within the range of 500-1,000 eq ha(-1) year(-1) as assessed by the RAINS-Asia model for this region. The present load of S and N (77.4 and 86.4 eq ha(-1) year(-1)) was much lower than the critical load of S and N (622.4 and 2,000 eq ha(-1) year(-1)), indicating that at present there is no harmful effect on ecosystem structure and function.     

Organochlorine insecticide residues in Ganga river water near Farrukhabad,India

Multiple residues of organochlorine insecticides were monitored in Ganga river water in the district of Farrukhabad in northern Indian for one year (1991–1992). Almost all the samples were found to be contaminated with residues of HCH and DDT. Residues of aldrin, endosulfan and heptachlor were also detected in a larger number of samples. Alpha-HCH, pp-DDT and alpha-endosulfan were found to dominate over the other isomers of HCH, DDT and endosulfan, respectively. Enhanced percentage of beta-HCH suggests accumulation of this isomer in the aquatic environment. The average concentration of aldrin was more than that of dieldrin. Aldrin residues often exceeded the WHO guideline value for drinking water and the concentration of heptachlor occasionally exceeded the specified limits.     

Seasonal variation of net ecosystem CO2 exchange and its influencing factors in an apple orchard in the Loess Plateau

Environmental Science and Pollution Research - The Loess Plateau is the largest apple cultivation region in the world. However, the role of rain-fed apple orchards as carbon sinks or sources,...