Spatial distribution and source identification of metal contaminants in soil and rice grain samples: a study on exploration of soil quality and risk assessment.

The present study aims to assess soil quality and potential health risks associated with soil pollution of the Batala region of Punjab, India. Physico-chemical parameters such as pH (6.69-7.43), electrical conductivity (0.17-0.33 mS/cm), and total organic carbon (1.01-5.94%) were observed to be within permissible limits. The maximum mean content (mg/kg) of heavy metals in soil was found as Fe (4060.93), Zn (444.33), Mn (278.5), Pb (23.16), Cu (21.78), Ni (20.16), Co (7.14), and Cd (1.85) which were below the prescribed limits but beyond the geochemical background limits of world soil. For rice grain samples, metal content (mg/kg) was seen as Fe (307.01) > Zn (12.41) > Mn (7.43) > Cu (4.57) and was below the permissible limits. The mean bioaccumulation factor for various metals was in the order as Zn > Cu > Fe > Mn. Single and integrated soil pollution indices revealed that among 18 sites, six were highly contaminated. The ecological risk index (Er) has shown that contamination of soil with Cd, Zn, and Ni was higher than that of other metals studied. The estimated daily intake of metal (EDI), hazard quotient (HQ), and hazard index (HI) were higher for children than those for adults. Spatial variability based on metal pollution load and soil quality was also determined using cluster analysis (CA) and principal component analysis (PCA). During CA, soil samples from 18 sites formed three statistically significant clusters based on the level of metal pollution at the specific site. PCA showed that all variables were reduced into two main components 1 and 2 with eigenvalues as 3.82 (47% variance) and 1.53 (19.7% variance), respectively.

A study on effects of cell phone tower-emitted non-ionizing radiations in an Allium cepa test system.

Considering enormous growth in population, technical advancement, and added reliance on electronic devices leading to adverse health effects, in situ simulations were made to evaluate effects of non-ionizing radiations emitted from three cell phone towers (T1, T2, and T3) of frequency bands (800, 1800, 2300 MHz), (900, 1800, 2300 MHz), and (1800 MHz), respectively. Five sites (S1-S5) were selected near cell phone towers exhibiting different power densities. The site with zero power density was considered as control. Effects of radiations were studied on morphology; protein content; antioxidant enzymes like ascorbate peroxidase (APX), superoxide dismutase (SOD), glutathione-S-transferase (GST), guaiacol peroxidase (POD), and glutathione reductase (GR); and genotoxicity using Allium cepa. Mean power density (µW/cm2) was recorded as 1.05, 1.18, 1.6, 2.73, and 12.9 for sites 1, 2, 3, 4, and 5, respectively. A significant change in morphology, root length, fresh weight, and dry weight in Allium cepa was observed under the exposure at different sites. Protein content of roots showed significant difference for samples at all sites while bulbs at sites S4 and S5 when compared to control. Antioxidant activity for root in terms of APX, GST, and POD showed significant changes at S4 and S5 and GR at site S5 and SOD at S1, S2, S3, S4, and S5. Similarly, bulbs showed significant changes at sites S4 and S5 for APX while at sites S3, S4, and S5 for POD and S2, S3, S4, and S5 for SOD and S5 for GR and GST. Genotoxicity study has shown induction of abnormalities at different stages of the cell cycle in Allium cepa root tips. The samples under exposure to radiation with maximum power density have shown maximum induction of oxidative stress and genotoxicity.

Assessment of spatial variations in pollution load of agricultural soil samples of Ludhiana district, Punjab.

Surveying, mapping, and characterizing soil properties are the critical steps in designating soil quality. Continuous use of inorganic fertilizers, pesticides, wastewater discharge, and leachates cause soil degradation and contamination of potable water and food ultimately leading to soil pollution and ill effects on human health. This study was undertaken to monitor the soil quality of agricultural soil samples collected from ten different agricultural fields in Ludhiana, Punjab (India), near Buddha Nullah, a Sutlej River tributary. Physico-chemical characteristics and heavy metal contents of soil samples were estimated during the study. The obtained results showed that all the agricultural soil samples were slightly alkaline in nature. Soil nutrients such as nitrates, phosphates, and potassium ranged from 0.06 to 0.11 mg/g, 0.03 to 0.08 mg/g, and 0.04 to 0.15 mg/g respectively. The contents (mg/kg) of heavy metals such as cadmium, chromium, cobalt, copper, and lead were observed to be above the permissible limits in most of the soil samples. Allium cepa root chromosomal aberration assay was used for genotoxicity studies which has shown that Hambran (HBN), a site approx. 12.9 km of the Buddha Nullah, induced maximum genotoxic effects, i.e., 46.7% aberrant cells in root tip cells of Allium cepa. The statistical analysis revealed the positive correlation of heavy metals like Cr, Cu, and Ni (at p ≤ 0.05 and p ≤ 0.01) with the total chromosomal aberrations induced in Allium cepa.

Assessment of the Heavy Metal Contamination of Roadside Soils Alongside Buddha Nullah, Ludhiana, (Punjab) India.

The present study was carried out to determine the physico-chemical characteristics and heavy metal contents in roadside soil samples collected during 2 sampling periods (September 2018 and April 2019) from 8 different roadside sites lying parallel to the Buddha Nullah, an old rivulet, flowing through Ludhiana, (Punjab) India. The contents (mg/kg) of seven metals (cadmium, chromium, cobalt, copper, lead, nickel and zinc) were estimated using a flame atomic absorption spectrophotometer. Among the metals analyzed, the contents of Cd, Co, Cu, Pb and Zn were found above the permissible limits. The results of the index of geoaccumulation (Igeo), contamination factor (CF), contamination degree (Cdeg), modified contamination degree (mCdeg), the Nemerow pollution index (PI) and pollution load index (PLI) indicate a moderate to high heavy metal contamination of the analyzed soil samples. The results of the potential ecological risk factor (ERi) and potential ecological risk index (RI) indicate a low to moderate risk of heavy metals in the studied soil samples. The Pearson correlation analysis revealed that most of the variables exhibited a statistically significant correlation with one or more variables during the two samplings. Multivariate analysis demonstrates that contents of heavy metals in the study area are influenced by anthropogenic and geogenic factors.

Investigation of metal concentrations in roadside soils and plants in urban areas of Amritsar, Punjab, India, under different traffic densities.

Vehicular emissions containing traces of different heavy metals are known to cause significant contamination of roadside soils and plants. The present study was conducted to investigate the heavy metal concentrations in roadside soil and plant samples (Alstonia scholaris, Nerium oleander, Tabernaemontana divaricata, and Thevetia peruviana) collected from urban areas of Amritsar city of Punjab, India, under different traffic densities. The soil and plant samples were collected in pre- and post-monsoon seasons from seven roadside sites under varying levels of traffic density and analyzed for four heavy metals (Cd, Cu, Pb, and Zn). In addition to that, total protein and carotenoid contents in plant samples were also determined. pH and electrical conductivity analysis of roadside soil samples revealed slight to strongly alkaline and non-saline nature of soil. Significant reduction in contents of total proteins and carotenoids was observed in plants collected from sites with moderate to high traffic density. The trend of heavy metal contents in plants and their corresponding soil samples was observed to be Zn > Cu > Pb > Cd for both the seasons. Index of geo-accumulation indicated moderate contamination of soil with metals analyzed, while bio-accumulation factor (BAF) showed both absorption and accumulation of metals in plants under study. The study revealed significant contamination of roadside soil and plants of Amritsar city which was linked to vehicular emissions posing potential risk to human health.

A study on water quality monitoring of Buddha Nullah, Ludhiana, Punjab (India).

Diverse genotoxic agents, entering the aquatic environment through natural and anthropogenic events, pose serious threats to its biotic components. The present study involves the monitoring of water quality by assessing the genotoxic effects and physico-chemical parameters including heavy metals of 10 surface water samples collected from different locations of Buddha Nullah, a tributary of Sutlej flowing through Ludhiana, Punjab (India). Genotoxicity was evaluated following Allium cepa root chromosomal aberration assay and DNA nicking assay using plasmid (pBR322) whilst the metal (cadmium, chromium, cobalt, copper, lead, nickel and zinc) analysis was conducted using atomic absorption spectrophotometer. All water samples collected from the study area had cobalt and lead content more than the permissible limits (0.04 and 0.01, respectively) recommended by the Bureau of Indian Standards and the World Health Organization. The samples also induced genotoxicity following both bioassays. The water samples collected from Gaunspur (GP), a site approx. 75.53 km upstream of the Sutlej-Buddha Nullah joining point, has shown the maximum genotoxic effect, i.e. 38.62% in terms of per cent total aberrant cells during A. cepa assay and 100% DNA damage during DNA nicking assay. The Pearson correlation indicated that genotoxicity had a significant positive correlation with the content of cobalt (at p ≤ 0.5). During cluster analysis, the samples from 10 sites formed four statistically significant clusters based on the level of pollution that was dependent on two factors like similarity in physico-chemical characteristics and source of pollution at a specific site.

Bioaccumulation potential of indigenous plants for heavy metal phytoremediation in rural areas of Shaheed Bhagat Singh Nagar, Punjab (India).

The present study was planned to explore the bioaccumulation potential of 23 plant species via bioaccumulation factor (BAf), metal accumulation index (MAI), translocation potential (Tf), and comprehensive bioconcentration index (CBCI) for seven heavy metals (cadmium, chromium, cobalt, copper, iron, manganese, and zinc). The studied plants, in the vicinity of ponds at Sahlon: site 1, Chahal Khurd: site 2, and Karnana: site 3 in Shaheed Bhagat Singh Nagar, Punjab (India), were Ageratum conyzoides (L.) L., Amaranthus spinosus L., Amaranthus viridis L., Brassica napus L., Cannabis sativa L., Dalbergia sissoo DC., Duranta repens L., Dysphania ambrosioides (L.) Mosyakin & Clemants, Ficus infectoria Roxb., Ficus palmata Forssk., Ficus religiosa L., Ipomoea carnea Jacq., Medicago polymorpha L., Melia azedarach L., Morus indica L., Malva rotundifolia L., Panicum virgatum L., Parthenium hysterophorus L., Dolichos lablab L., Ricinus communis L., Rumex dentatus L., Senna occidentalis (L.) Link, and Solanum nigrum L. BAf and Tf values showed high inter-site deviations for studied metals. MAI values were found to be more substantial in shoots as compared with that of roots of plants. Maximum CBCI values were observed for M. azedarach (0.626), M. indica (0.572), D. sissoo (0.497), and R. communis (0.474) for site 1; F. infectoria (0.629), R. communis (0.541), D. sissoo (0.483), F. palmata (0.457), and D. repens (0.448) for site 2; D. sissoo (0.681), F. religiosa (0.447), and R. communis (0.429) for site 3. Although, high bioaccumulation of individual metals was observed in herbs like C. sativa, M. polymorpha, and Amaranthus spp., cumulatively, trees were found to be the better bioaccumulators of heavy metals.

A comparative study for removal of cadmium(II) ions using unmodified and NTA-modified Dendrocalamus strictus charcoal powder.

Release of cadmium, a non-essential and highly toxic heavy metal, into aquatic ecosystem through discharge of effluents from various industries such as electroplating, photographic, steel/iron production and tanneries, is of considerable environmental conern at global level. Hence, it is essential to develop economic methods to remove cadmium from industrial effluents before their discharge into water bodies. The aim of present study was to explore the efficiency of Nitrilotriacetic acid (NTA) for the surface modification of Dendrocalamus strictus charcoal powder (DCP) and application of both unmodified DCP and NTA modified DCP (NTA-MDCP) as adsorbents to remove cadmium (II) ions from aqueous solution. Isotherms, thermodynamic and kinetic studies were carried out to describe the adsorption behavior of both adsorbents for the removal of Cd(II) ions. Maximum adsorption capacity calculated from Langmuir isotherm was found to be higher for NTA-MDCP (166.66 mg/g) as compared to DCP (142.85 mg/g) which may be attributed to the complex formation (1:1 & 2:1) between NTA on the surface of adsorbent and Cd(II) ions in the solution at optimum conditions: pH = 6, temperature = 25 °C, adsorbent dose = 2 g/l and contact time = 2 h. Thermodynamic studies confirmed endothermic as well as spontaneous nature of adsorption process and kinetic investigation revealed that the adsorption process followed pseudo second-order for both DCP and NTA-MDCP. Physical characterization of both adsorbents before and after adsorption was studied using Scanning Electron Microscope, Brunauer-Emmett-Teller surface analyzer, Energy Dispersion X-ray Spectrometer, CHNS analyzer and X-Ray diffractometer which confirmed the adsorption of cadmium(II) ions. Further, the desorption studies for regeneration of adsorbents were successfully carried out using two eluents viz., 1 M sulfuric acid and 0.5% calcium chloride. The present study revealed that NTA-MDCP could be used as an effective adsorbent for the removal of cadmium(II) ions from aqueous solution.

Sorption technique as a tool for reduction of genotoxicity.

In the present study, the Allium cepa root chromosomal aberration assay was used to determine the genotoxic effects of copper and cadmium ions solutions before and after sorption processes. The sorption process was carried out using unmodified Dendrocalamus strictus charcoal powder, nitrilotriacetic acid (NTA)-modified D. strictus charcoal powder, and Saccharomyces cerevisiae. The frequency of total chromosomal aberrations was observed to be 24.30-45.13% for copper and 13.16-45.14% for cadmium at different concentrations (1-500 mg/l) before the sorption process. Both metal ions solutions resulted in significant reduction of chromosomal aberrations after all the modes of the sorption processes. However, the order of reduction of percentage chromosomal aberrations for copper and cadmium solutions was found to be 45.29-70.04% and 47.80-84.57%, respectively (NTA-modified D. strictus charcoal powder); >44.53-54.32% and 37.10-79.40%, respectively (unmodified D. strictus charcoal powder); >15.59-48.51% and 13.63-21.50%, respectively (S. cerevisiae).

Dendrocalamus strictus Charcoal: An Efficient Adsorbent for Removal of Cu (II) Ions from Aqueous Solution and its Applicability in the Reduction of Genotoxic Potential of Cu (II) Ions.

The present study pertains to evaluate the efficiency of Dendrocalamus strictus charcoal powder as an adsorbent to adsorb copper ions from aqueous solution under different conditions of pH, initial metal ion concentration, adsorbent dose, contact time, and temperature. Physical characterization of Dendrocalamus strictus charcoal powder was performed using different techniques such as scanning electron microscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy, Brunauer Emmett and Teller surface analysis and X-ray diffraction. Langmuir, Freundlich, and Temkin isotherm models were employed to describe the adsorption behavior of adsorbent in the removal of copper ions from aqueous solution. Thermodynamic parameters indicated that the adsorption of copper ions onto the surface of the adsorbent was feasible, spontaneous, and endothermic in nature. Data analysis using kinetic models revealed the pseudo-second-order as the suitable model to describe the process of adsorption. Studies were further carried out to analyze the genotoxic effects of copper ions in aqueous solution before and after adsorption, using Allium cepa assay. This study revealed that Dendrocalamus strictus charcoal powder could be applied as an alternative for more costly adsorbents in the detoxification of copper ions from aqueous solution.

Polyphenols in Food: Cancer Prevention and Apoptosis Induction.

Polyphenols are a group of water-soluble organic compounds, mainly of natural origin. The compounds having about 5-7 aromatic rings and more than 12 phenolic hydroxyl groups are classified as polyphenols. These are the antioxidants which protect the body from oxidative damage. In plants, they are the secondary metabolites produced as a defense mechanism against stress factors. Antioxidant property of polyphenols is suggested to provide protection against many diseases associated with reactive oxygen species (ROS), including cancer. Various studies carried out across the world have suggested that polyphenols can inhibit the tumor generation, induce apoptosis in cancer cells and interfere in progression of tumors. This group of wonder compounds is present in surplus in natural plants and food products. Intake of polyphenols through diet can scavenge ROS and thus can help in cancer prevention. The plant derived products can also be used along with conventional chemotherapy to enhance the chemopreventive effects. The present review focuses on various in vitro and in vivo studies carried out to assess the anti-carcinogenic potential of polyphenols present in our food. Also, the pathways involved in cancer chemopreventive effects of various subclasses (flavonoids, lignans, stilbenes and phenolic acids) of polyphenols are discussed.

Analysis on bioaccumulation of metals in aquatic environment of Beas River Basin: A case study from Kanjli wetland.

Wetlands, the biological filters of the Earth, play an important role in biochemical transformation of various pollutants. Wetland plants, in this direction, help in accumulating various contaminants from aquatic bodies. Considering this, the present study was planned to estimate different metals (Cd, Cu, Cr, Co, Fe, Pb, Zn, and Mn) in water, sediment, soil, and plant (4 aquatic and 12 terrestrial) samples of Kanjli wetland, Kapurthala, Punjab (India), and a Ramsar site. It was observed that the contents of Cd and Pb in water samples were higher than limits prescribed by Bureau of Indian standards. Bioaccumulation and translocation factors for various metals were also calculated. Although all the plant species were found to be hyperaccumulator for one or the other metal studied, maximum six metals (Cd, Co, Fe, Mn, Pb, and Zn) were bioaccumulated in Panicum antidotale among aquatic plant species while (Cd, Cu, Fe, Mn, Pb, and Zn) in Lantana camara and Ageratum conyzoids among terrestrial plants species. It is evident that all these plants have potential to phytoremediate various inorganic pollutants and can act as bioindicators. The physicochemical characteristics revealed high biochemical oxygen demand (BOD) and nitrate (NO3) contents and low dissolved oxygen (DO) in water samples while the high content of phosphates in soil and sediment samples.

Heavy metals in vegetables: screening health risks involved in cultivation along wastewater drain and irrigating with wastewater.

Irrigation of agricultural land with wastewater leads to continuous buildup of metals at these sites which gets accumulated in the vegetables and crops growing on these sites. Not just the crops irrigated with wastewater are hazardous, in present study, we have found that vegetables growing in vicinity of wastewater drain are also not safe for human consumption. The risk associated with consumption of vegetables was assessed by calculating hazard quotient and results revealed that the hazard quotient for leafy and tuberous vegetables was higher than the safe limits in all the sites irrespective of mode of irrigation. Spinach was the most hazardous among all as the hazard quotient with respect to cobalt and copper was highest in spinach. Uptake trend of metals in all vegetables: Iron > Cobalt > Copper > Cadmium > Lead. Cadmium, a potential carcinogen was found in concentrations higher than permissible limits in many vegetables from all sites. Highest level of cadmium (1.20 mg/kg) and copper (81.33 mg/kg) was reported in site which was in vicinity of waste water drain but irrigated with ground water. Concentration of copper and lead in vegetable samples from different sites exhibited no statistically significant difference with respect to different sites.

Analytical techniques for estimation of heavy metals in soil ecosystem: a tabulated review.

Soil, an important environmental medium, is exposed to a number of pollutants including toxic heavy metals by various natural and anthropogenic activities. Consequently heavy metal contaminated soil has the potential to pose severe health risks and hazards to humans as well as other living creatures of the ecosystem through various routes of exposure such as direct ingestion, contaminated drinking ground water, food crops, contact with contaminated soil and through food chain. Therefore, it is mandatory to explore various techniques that could efficiently determine the occurrence of heavy metals in soil. A number of methods have been developed by several regulatory agencies and private laboratories and are applied routinely for the quantification and monitoring of soil matrices. The present review is an initiative to summarize the work on pollution levels of soil ecosystem and thus pertains to various extraction and quantification procedures used worldwide to analyze heavy metals in soil.

Preliminary analysis of polycyclic aromatic hydrocarbons in air particles (PM10) in Amritsar, India: sources, apportionment, and possible risk implications to humans.

Preliminary analysis was performed to assess human health risks of exposure to 16 polycyclic aromatic hydrocarbons (PAHs) by way of inhalation by children and adults living in urban area of Amritsar, Punjab, India. In particular, the United States Environmental Protection Agency's (USEPA's) 16 priority PAH compounds were analyzed in air particulate matter (PM10) from different geographical locations by high-volume air sampler. Sum concentrations of PAHs (37-274 ng m(-3)) were comparable with those of other cities in India as well many cities on a global scale. Pyrene, naphthalene, acenaphthene, acenaphthylene, fluoranthene, fluorene, and dibenzo(a,h)anthracene accounted for >80% of ∑16PAH concentrations. Furthermore, the contribution of seven carcinogenic PAHs accounted for 12% of ∑16PAHs. The estimated carcinogenicity of PAHs in terms of benzo(a)pyrene toxic equivalency (BaPTEQ) was assessed and confirmed that dibenzo(a,h)anthracene was the dominant PAH contributor (88.7%) followed by benzo(a)pyrene (6.67%). Homolog pattern and diagnostic ratios of PAHs suggested that mixed pyrogenic sources--including biomass burning, coal combustion, and petrogenic sources, such as vehicular emissions--are dominant PAH sources in Amritsar. Health risk of adults and children by way of PAHs was assessed by estimating the lifetime average daily dose (LADD) and corresponding incremental lifetime cancer risk (ILCR) using USEPA guidelines. The assessed cancer risk (ILCR) was found to be within the acceptable range (10(-6)-10(-4)).

Evaluation of genotoxic potential of industrial waste contaminated soil extracts of Amritsar, India.

The rapid increase in population together with unplanned disposal of effluents from various industries has resulted in accumulation of various heavy metals like As, Cr, Cu, Hg, Ni, Pb and Zn in soil ecosystem which ultimately causes DNA damage in living systems. Considering this, the present study was designed to evaluate the content of various heavy metals (Cu, Cr, Co, Hg, Mn, Ni, Zn) and genotoxicity/mutagenicity of soil samples collected from the outskirts of two industries viz. zinc coating industry (SI) and copper sulphate manufacturing industry (SII) employing Allium root anaphase aberration assay (A/RAAA) and Ames assay. The physicochemical parameters like bulk density, water holding capacity, moisture content, pH, nitrates, phosphates and potassium were also estimated. It was observed that SI sample contained Ni (6.86 mg g-1), Zn (6.53 mg g-1), Co (5.05 mg g-1) and Cr (4.49 mg g-1), while SII contained Cu (32.86 mg g-1), Ni (9.66 mg g-1), Co (6.85 mg g-1) and Zn (5.41 mg g-1). In A/RAA assay, the percentage of cells with anaphase aberrations ranged from 3.63 to 10.67 and 0.38 to 4.83% for samples SI and SII, respectively. In Ames test, sample SII was found to be lethal to Salmonella tester strains at all concentrations used, while sample SI was found to be mutagenic in TA100 strains of Salmonella typhimurium. Sample SII was found to be strongly acidic with pH 3.46. The present study focuses on the increasing heavy metal pollution in Amritsar city due to industrial discharges over lands and also infers that both bioassays Ames and A/RAAA can serve as first alert indication of pollution.

Analytical methods for estimation of organophosphorus pesticide residues in fruits and vegetables: a review.

Use of pesticides has turned out to be an obligatory input to agriculture and public health. Versatile use of pesticides had resulted in contamination of all basic necessities of life, i.e. air, water and food. Among various pesticides, organophosphorus pesticides (OPPs), derivative of phosphoric acid, are the most extensively used insecticides or acaricides in many crops. Due to low persistency and high killing efficiency of OPPs, many agriculturalists regularly use this group of pesticides for various vegetables and fruits crops. The continuous use of pesticides has caused the deleterious effects to ecosystem. In response to this, a number of methods have been developed by several regulatory agencies and private laboratories and are applied routinely for the quantification and monitoring of multi pesticide residues in vegetables and crops. The present review pertains to various extraction and quantification procedures used world wide to analyze OPPs residues in various vegetables and fruits.