S. Sadasivan

Blood lead and its effect on Cd, Cu, Zn, Fe and hemoglobin levels of children

The levels of heavy metals, such as Pb, Cd, Cu, Zn and Fe, in whole blood samples of Mumbai and Hyderabad children have been determined. In the present study, 576 blood samples of children (3-6 years old) were collected during 1996-1998 and analyzed for heavy metal contents by anodic stripping voltammetry and atomic absorption spectrometry. The geometric mean concentrations of Pb, Cd, Cu and Zn in blood of Mumbai children were 8.0, 0.10, 86.5 and 398.9 microg dl(-1), while those for Hyderabad children were 13.3, 0.13, 100.6 and 483.4 microg dl(-1) respectively. The geometric mean concentrations of Fe in the blood of Mumbai and Hyderabad children were 21.9 and 34.5 mg dl(-1), respectively. Of the Mumbai children, 61.8% were found to have a blood lead concentration lcss than 10 microg dl(-1), while the corresponding proportion of Hyderabad children was 27.4%. Higher concentrations of Pb in the childrens blood were observed at high traffic areas in both cities. A decreasing trend in the hemoglobin content with increasing blood lead levels was observed for Mumbai children. A good negative correlation (-0.61) between the blood lead and iron has been observed for Mumbai children The hemoglobin content of 85% of the study population was found to vary between 8 and 14 g%.

Precipitation scavenging of polycyclic aromatic hydrocarbons in Mumbai, India

The concurrent rain and air sampling was conducted for thirteen rain events between the last week of May and end of June 2001. Concentration of total PAHs varied from 84.25 to 777.49 ng/l whereas that in air was in the range of 4.05 to 34.42 ng/m(3). In rainwater the lower molecular weight PAHs (e.g. Phenanthrene, Fluoranthene and Pyrene) were found to be more prominent than the higher molecular weight compounds. The gas phase scavenging ratio (Wg) was found to increase with the molecular weight of the compound. The particle phase scavenging ratio (Wp) values for the more volatile PAHs were generally much higher than those for less volatile PAHs. The higher MW PAHs have Wg values equal to or larger than their Wp values.

Aerosol composition and sources in Urban areas in India

Abstract The elemental composition of aerosols over four cities in India was determined by EDXRF over a 1-year period and the results are presented. The crustal element levels in air in all the cities are found to be similar to those reported for urban areas elsewhere in the world while that of anthropogenic elements are lower. The aerosol compositions show a seasonal variation. The levels of crustal elements are higher during summer and decrease with rainfall. The anthropogenic elements are generally higher during winter. The lead levels are essentially from non-auto exhaust sources such as refuse burning, smelter etc., and in three of the cities they are strongly correlated to zinc. The crustal elements are from local soils and no significant crust-air fractionation is seen. Factor analysis of the data suggests between four and six aerosol source types for the four cities. Soil dust accounts for the major fraction of the measured mass. About 68–80 % of the aerosol mass comprising the residuals seems to consist of C, O 2 and N, in particular, which were not measured.

Trace elements in size separated aerosols over sea

Abstract Aerosol samples were collected over the Arabian Sea along 20°N latitude using a four stage cascade impactor with a back-up filter. Concentrations of Cl, Na, Br, I, Mn, Fe, Zn, Cr, Sb and Sc in these samples were determined by neutron activation analysis. The measurements show that aerosols of continental origin contribute considerably to the total aerosol population. The soil origin elements Mn, Cr and Fe and the seawater derived elements I and Br are present in significant amounts in particles below 0.1 μm radius. The results suggest fractionated transfer of I and Br from seawater to air. Even over sea, a Cl loss in the sub-micron particles is found to occur. The Cl/Na ratios observed in the different aerosol fractions can explain the fact that comparable concentrations of Cl in the gaseous and paniculate forms have been measured in marine atmosphere by others.

Selenium levels in biological matrices in adult population of Mumbai, India

Selenium (Se) levels in whole blood, serum, urine, muscle and saliva of Mumbai adults have been estimated by differential pulse cathodic stripping voltammetry (DPCSV); the detection limit of Se is 0.05 ng ml(-1). The reliability of estimation is further assessed through the analysis of Standard Reference Materials. The Se levels in whole blood (n = 35) and blood serum (n = 201) of the Mumbai adult population is 99.6 and 100 ng ml(-1); approximately 34.8% of the population have serum Se levels between 80 and 100 ng ml(-1). The blood serum levels of Se for Mumbai adults are comparable to those of whole blood. The mean concentration of Se in urine on a 24-h basis is 5.2 ng ml(-1). Muscle and saliva of the Mumbai adult population contain 195.4 ng g(-1) and 2 ng ml(-1) of Se, respectively. A good correlation between serum Se and dietary Se is observed with a correlation coefficient of 0.89.

Daily intake of aluminium by adult population of Mumbai, India

Electrothermal atomic absorption spectrophotometry (ET-AAS) has been used for the determination of Al in environmental and food samples with a detection limit of 0.3 ng ml(-1). The reliability of estimation is assessed through the analysis of Standard Reference Materials (IAEA SRMs) of Soil-7, SL-3, SD-M2/TM and Hay (V-10). The results indicate that the average concentration of aluminium in air particulate samples is 5.3 microg m(-3). The daily intake of Al by the adult population of Mumbai is 6.4 mg day(-1).

Elemental characterization of atmospheric aerosols

Aerosol samples collected at Bombay on a daily basis were characterized by two instrumental methods, instrumental neutron activation analysis (INAA) and energy dispersive X-ray fluorescence (EDXRF). A total of 28 elements was measured in the samples and the results are presented. Using factor analysis, seven sources were identified as contributing to the aerosol mass at the sampling site. The measured elements accounted for ∼24% of the total suspended particulate matter, with associated C, O2 and N in particular comprising the residual mass. Air concentrations of elements with an anthropogenic origin showed a larger variation in the samples than those derived from soil. EDXRF analysis is advantageous for the analysis of bulk samples of ambient air particulates. The frequency distributions of trace elements in air are also discussed.

Daily intake of Se by adult population of Mumbai, India

The atmospheric Se levels in Mumbai varied between 0.02 and 1.92 ng m(-3) with a mean concentration of 0.21 ng m(-3). The daily intake of Se by the adult population of Mumbai is 61.9 microg day(-1). Differential pulse cathodic stripping voltammetry (DP-CSV) has been used for the determination of Se in air particulate and food samples. The detection limit of Se using DPCSV was found to be 0.05 ng ml(-1). The reliability of estimation was further assessed through the analysis of standard reference materials (SRMs), tuna fish, animal blood, milk powder and fish tissue obtained from IAEA. The frequency distribution of dietary intake levels of selenium for Mumbai adults showed that approximately 61% of the studied population have a dietary intake of 30-90 microg day(-1). Ingestion was found to be the main route of Se exposure for Mumbai adults. The turn over time of Se through blood is 17 days.

Atmospheric and children's blood lead as indicators of vehicular traffic and other emission sources in Mumbai, India.

Average concentration of Pb in atmospheric air particulates in different suburbs of Mumbai was studied for almost a decade and its spatial and temporal profiles are discussed in relation to emission sources. In general the concentration of Pb in all the residential suburban atmosphere is well below the Central Pollution Control Board (CPCB, 1994) prescribed limit of 1.5 microg m(-3) barring a few exceptions for some residential/industrial sites, such as those of Thane and Kurla scrap yards. The correlation between blood lead of children and air lead reveals that the blood Pb level in children could increase by 3.6 microg dl(-1) for an incremental rise of 1.0 microg Pb m(-3) of air. The temporal profile of air Pb values indicates a decreasing trend in residential suburbs (Khar: 1984, 0.39 microg m(-3); 1996, 0.17 microg m(-3)) as well as in suburban residential areas with low traffic (Goregaon: 1984, 0.53 microg m(-3); 1996, 0.30 microg m(-3)).

Trace constituents in cloud water, rainwater and aerosol samples collected near the west coast of india during the southwest monsoon

Abstract Cloud water, rainwater and impactor aerosol samples were collected at a mountain top near the west coast of India during the summer monsoon and analysed for several trace constituents. The results reveal that there is considerable contribution to cloud nuclei from non-seasalt aerosols. Nearly half the sulphate in the cloud water is from sources other than seasalt. There is no evidence for absorption of gaseous halogens in cloud droplets. The chemical composition of cloud water is influenced by both large and giant aerosol particles. Gaseous iodine is not absorbed to any significant extent on raindrops. The results also indicate that there is no appreciable fractionation of Mg in the transfer from seawater to air.