Satellite or ground-based measurements for air pollutants (PM2.5, PM10, SO2, NO2, O3) data and their health hazards: which is most accurate and why?

Air pollution is growing at alarming rates on regional and global levels, with significant consequences for human health, ecosystems, and change in climatic conditions. The present 12 weeks (4 October 2021, to 26 December 2021) study revealed the different ambient air quality parameters, i.e., PM2.5, PM10, SO2, NO2, and O3 over four different sampling stations of Delhi-NCR region (Dwarka, Knowledge park III, Sector 125, and Vivek Vihar), India, by using satellite remote sensing data (MERRA-2, OMI, and Aura Satellite) and different ground-based instruments. The ground-based observation revealed the mean concentration of PM2.5 in Dwarka, Knowledge park III, Sector 125, and Vivek Vihar as 279 µg m-3, 274 µg m-3, 294 µg m-3, and 365 µg m-3, respectively. The ground-based instrumental concentration of PM2.5 was greater than that of satellite observations, while as for SO2 and NO2, the mean concentration of satellite-based monitoring was higher as compared to other contaminants. Negative and positive correlations were observed among particulate matter, trace gases, and various meteorological parameters. The wind direction proved to be one of the prominent parameter to alter the variation of these pollutants. The current study provides a perception into an observable behavior of particulate matter, trace gases, their variation with meteorological parameters, their health hazards, and the gap between the measurements of satellite remote sensing and ground-based measurements.

Investigation of heavy metal contamination and associated health risks in groundwater sources of southwestern Punjab, India.

Human body exposure to various toxic and non-toxic heavy metals in groundwater is a significant health concern, especially in developing countries. The present study was planned and carried out to appraise the potential health risks of eight heavy metals (Mn, Co, Cu, As, Se, Cd, Hg, and Pb) in different water sources of the Mansa and Muktsar districts of Punjab. The measurements of heavy metals were performed using the inductively coupled plasma mass spectrometry (ICPMS) technique. The health (carcinogenic and non-carcinogenic) risks and doses (ingestion and dermal) associated with exposure to heavy metals in water were estimated from the measured concentrations using USEPA guidelines. The average concentrations of heavy metals were observed in the order of Mn (13.93) > Cu (13.12) > Se (4.14) > As (3.28) > Hg (3.27) > Pb (1.29) > Co (0.20) > Cd (0.10) µg L-1. The results show that the Hg, Pb, As, and Se concentrations are above the guideline values of the World Health Organization (WHO) in 10.34%, 3.45%, 6.90%, and 6.90% locations, respectively. The high values of these heavy metals may be due to geogenic anthropogenic activities. The hazard quotients (non-carcinogenic risk) for ingestion and dermal exposures were observed in the range of 0.32-3.79 and 8.05 × 10-6-1.34 × 10-4, respectively. On the other hand, the carcinogenic health risks due to ingestion and dermal exposure were observed to be 0.02-0.38 and 6.67 × 10-8-1.15 × 10-6, respectively. The results of this study will be helpful to the drinking water supplying agencies, water resource development authorities, etc.

Sensitivity of normalized difference vegetation index (NDVI) to land surface temperature, soil moisture and precipitation over district Gautam Buddh Nagar, UP, India.

This study examines the trends in MODIS/TERRA derived Normalized Difference Vegetation Index (NDVI) and its correlation with Land Surface Temperature (LST), Soil Moisture (SM), and precipitation over Gautam Buddh Nagar (India), during the period 2005-2018. The region have a sub-humid and quite moderate climate, scattered into cultivable land, forest and fast growing urbanization zone, making it suitable for monitoring vegetation trends and its accompanying factors. The NDVI-derived vegetation growth patterns over the study region of District Gautam Buddh Nagar, illustrate vigorous seasonal cycles, and interannual variations. The correlation between NDVI, and LST (- 0.45) was observed to be higher than the correlation of NDVI with SM (r = 0.43), and precipitation (r = 0.341), suggesting NDVI as more sensitive to LST as compare to SM, and precipitation, while SM shows the worthy positive correlation (r = 0.63) with the precipitation. On a seasonal basis, NDVI shows high values during winter (0.45 ± 0.02) followed by monsoon (0.44 ± 0.04), post-monsoon (0.41 ± 0.02), and pre-monsoon (0.37 ± 0.04). This study also aims to determine the phase wise status of NDVI and associated parameters.

Radiological and pollution risk assessments of terrestrial radionuclides and heavy metals in a mineralized zone of the siwalik region (India).

The present study reveals the distribution of terrestrial radionuclides (226Ra, 232Th and 40K) and heavy metals (Cr, Ni, Cu, Zn, Pb, Co) from soil samples of Una, Hamirpur and Kangra districts of Himachal Pradesh (India). The 226Ra, 232Th, 40K activity concentration in the studied region has been varied from 8 to 3593 Bq kg-1; 21-370 Bq kg-116; 62-7130 Bq kg-1 respectively. High disequilibrium factor (238U/226Ra) depicts that uranium constantly migrates from clay oxidizing zone and getting precipitated with enrichment towards south. An attempt has been made to correlate the distribution of these radionuclides and heavy metals with geology and rock type formation of Siwalik region. The concentration of Pb, Zn and Co was found higher than Indian average background value. Multiple radiological and pollution indices have been estimated for proper risk analysis in the studied region. The annual effective dose in studied region is lower than the recommended limit of 1.0 mSv a-1. The obtained geo-accumulation index and enrichment factor indicated that the sites located in the Hamirpur and Kangra regions were moderately contaminated with Pb and Co. The Nemerow pollution index and contamination security index suggested that almost 45% sites were slightly to moderately polluted. The non-carcinogenic and carcinogenic risks for both children and adults were within acceptable limits.

Quantification of an alpha flux based radiological dose from seasonal exposure to 222Rn, 220Rn and their different EEC species.

This study summarizes the seasonal experimental data on the activity concentrations of indoor 222Rn (Radon), 220Rn (Thoron) and their progeny in Mansa and Muktsar districts of Punjab (India) using LR-115 solid state nuclear track detector based time integrated pin-hole cup dosimeters and deposition based progeny sensors for the assessment of radiological dose. The indoor 222Rn concentration was observed higher in the rainy and winter seasons while 220Rn concentration was observed higher in the winter season. However, Equilibrium Equivalent Concentrations (EECs) of 222Rn and 220Rn exhibited distinct seasonal behaviour unlike their parent nuclides. The average equilibrium factors for 222Rn (FRn) and 220Rn (FTn) were found 0.47 ± 0.1 and 0.05 ± 0.01, respectively. The annual arithmetic means of unattached fractions of 222Rn ([Formula: see text]) and 220Rn ([Formula: see text]) were found to be 0.09 ± 0.02 and 0.10 ± 0.02, respectively. The attachment rate (XRn) and attachment rate coefficients (ß) of 222Rn progeny were also calculated to understand the proper behaviour of progeny species in the region. A new alpha flux based technique has been proposed and used for the assessment of absorbed dose rate and annual effective dose rate for radiation protection purpose.

Structural, photoluminescence and dielectric investigations of phosphatic shale.

In the current study, the structural and spectroscopic properties of phosphatic shale samples obtained from the Atomic Minerals Directorate for Exploration and Research were probed for potential use as a phosphor material. X-ray diffraction and Raman and Fourier transform infrared spectroscopy revealed that the beneficiated phosphatic shale samples were primarily monophasic consisting of fluorapatite [Ca5 (PO4 )3 F, (FAP)] with minor traces of haematite (α-Fe2 O3 ) and calcite (CaCO3 ). Energy dispersive X-ray fluorescence revealed the presence of U, Eu, Dy and Tb in the FAP matrix substituted at Ca(I) and Ca(II) sites of FAP. A reduced optical direct band gap of 4.46 eV was calculated from the Tauc plot. Photoluminescence spectral studies revealed multicolour emissions (red, yellow, green and blue) on ultraviolet light excitation that were attributed to luminescence spectra from rare earth ions Eu3+ , Tb3+ , U4+ and U6+ in the FAP matrix. The overall emissions for the rare earth and actinide-doped FAP were obtained in the cool white region and the corresponding Commission Internationale de l'Eclairage chromaticity coordinates were calculated to be (0.274, 0.317). The corresponding colour correlated temperature obtained was 9342 K. Furthermore, phosphatic shale had a high room temperature dielectric constant of 11 at a frequency of 1 kHz that demonstrated its suitability for use in biological sensors. The study showed that natural phosphatic shale could be a potential material for optical, biological and dielectric applications.

Estimation of Radiological Dose From Progeny of 222Rn and 220Rn Using DTPS/DRPS and Wire-Mesh-Capped Progeny Sensors.

Radon (222Rn) and its decay products are the major sources of natural radiation exposure to general population. The activity concentrations of unattached and attached short-lived 222Rn and thoron (220Rn) progeny in indoor environment of some dwellings of the Jalandhar and Kapurthala districts of Punjab had been calculated using the deposition-based progeny sensors (DRPS/DTPS) and wire-mesh-capped (DRPS/DTPS) progeny sensors. The observed concentration of attached 222Rn and 220Rn progeny showed the variation from 5 to 21 Bq·m-3 and 0.3 to 1.7 Bq·m-3, respectively. The activity concentration of the unattached 222Rn and 220Rn progeny varies from 1 to 5 Bq·m-3 and 0.1 to 0.6 Bq·m-3, respectively. The average unattached fraction of 222Rn and 220Rn progeny is 0.2 and 0.1. The average value of the indoor aerosol concentration attachment rate of 222Rn and 220Rn progeny is 2251 cm-3, 24 ms-1, and 617 ms-1. Relation among the unattached fraction and attachment rate is established, and the obtained results of dose conversion factors show the significance of the nano-sized 222Rn decay products in 222Rn dosimetry.

STUDY OF NATURAL RADIOACTIVITY (226Ra, 232Th AND 40K) IN SOIL SAMPLES FOR THE ASSESSMENT OF AVERAGE EFFECTIVE DOSE AND RADIATION HAZARDS.

The activity concentration of 226Ra (radium), 232Th (thorium) and 40K (potassium) has been measured in the soil samples collected from Mansa and Muktsar districts of Punjab (India) using NaI (Tikl) gamma detector. The concentration of three radionuclides (226Ra, 232Th and 40K) in the studied area has been varied from 18±4 to 46±5, 53±7 to 98±8 and 248±54 to 756±110 Bq kg-1, respectively. Radium equivalent activities (Raeq) have been calculated in soil samples for the assessment of the radiation hazards arising due to the use of these soil samples. The absorbed dose rate of 226Ra, 232Th and 40K in studied area has been varied from 8 to 21, 33 to 61 and 9 to 25 nGy h-1, respectively. The corresponding indoor and outdoor annual effective dose in studied area was 0.38 and 0.09 mSv, respectively. The external and internal hazard has been also calculated for the assessment of radiation hazards in the studied area.

Estimation of EEC, unattached fraction and equilibrium factor for the assessment of radiological dose using pin-hole cup dosimeters and deposition based progeny sensors.

High concentration of radon ((222)Rn), thoron ((220)Rn) and their decay products in environment may increase the risk of radiological exposure to the mankind. The (222)Rn, (220)Rn concentration and their separate attached and unattached progeny concentration in units of EEC have been measured in the dwellings of Muktsar and Mansa districts of Punjab (India), using Pin-hole cup dosimeters and deposition based progeny sensors (DTPS/DRPS). The indoor (222)Rn and (220)Rn concentration was found to vary from 21 Bqm(-3) to 94 Bqm(-3) and 17 Bqm(-3) to 125 Bqm(-3). The average EEC (attached + unattached) of (222)Rn and (220)Rn was 25 Bqm(-3) and 1.8 Bqm(-3). The equilibrium factor for (222)Rn and (220)Rn in studied area was 0.47 ± 0.13 and 0.05 ± 0.03. The equilibrium factor and unattached fraction of (222)Rn and (220)Rn has been calculated separately. Dose conversion factors (DCFs) of different models have been calculated from unattached fraction for the estimation of annual effective dose in the studied area. From the experimental data a correlation relationship has been observed between unattached fraction (f(p)(Rn)) and equilibrium factor (F(Rn)). The present work also aims to evaluate an accurate expression among available expression in literature for the estimation of f(p)(Rn).

Estimation of attached and unattached progeny of 222Rn and 220Rn concentration using deposition based progeny sensors.

The attached and unattached radon and thoron progeny concentrations have been calculated using deposition-based progeny sensors in Mansa, Muktsar, Bathinda and Faridkot districts of Punjab, India. The total (attached + unattached) equilibrium-equivalent (222)Rn concentration (EECRA + U) and total (attached + unattached) equilibrium-equivalent (220)Rn concentration (EECTA + U) were found to vary from 9 to 46 Bqm(-3) and 0.5 to 3.1 Bq m(-3), respectively. The concentrations of attached progeny nuclides for both (222)Rn and (220)Rn have been found to be greater than the unattached progeny nuclides in the dwellings of studied area. An attempt has also been made to assess the effective dose for (222)Rn and (220)Rn in the studied area. The radiation dose originated from (222)Rn and (220)Rn progeny is low and health risk is negligible.