High Degree Of Contamination Research Articles

Ecological and Risk Assessment of Heavy Metals in a Diverse Industrial Area of Al-Akrasha, Egypt

This study was conducted in one of a diverse industrial area in Al-Akrasha, Egypt. Concentrations of select metals (Cu, Pb, Cr, Ni, Zn, Mn, Cd, Al, Ag, As, B, and Fe) were evaluated in ambient PM10 and surface soils at nine sites. Random samples of fresh edible tilapia fish were collected from Ismailia Canal at two sites near the Al-Akrasha region. In addition, blood and hair samples were collected from workers and residents living in Al-Akrasha as biomarkers of contamination with these metals. The ecological and health risks of these metals to the workers and residents living in the Al-Akrasha region were assessed. The results showed that heavy metal levels in the ambient air (PM10) of the Al-Akrasha region were higher than the national and international guidelines. There was a very high degree of contamination (CD > 32) of the surface soil in the Al-Akrasha area, which can be attributed to industrial activities emissions, mostly from smelters and the subsequent deposition on the surface soil. Ingestion was the dominant pathway for metals to enter the human body in the Al-Akrasha region. Adults have a higher daily intake and exposure risk than infants and children.

Assessment of trace elements in the long-term banana cultivation field’s soil

This work assesses the contamination of trace elements (Cr, Cu, Ni, As, Zn Cd, Mn, Fe, and Pb) in soil and different tissues of the banana plant (Musa spp.), the ecological risks of trace elements using various indices, and the probable health risks using a chemometric approach. Soil and different banana plant tissues were collected from banana fields around the industrial area of the capital of old Pundranagar (the earliest urban archaeological location), Bangladesh. Samples were digested by acid digestion, and trace elements were measured by inductively coupled plasma spectrophotometer (ICP-MS). The concentrations of Cr, Ni, Cu, As, Cd, Pb, Fe, Mn, and Zn in soil ranged from 1.50–61.7, 2.42–87.4, 2.00–100.8, 0.25–31.2, 0.10–12.7, 0.60–91.8, 11330–23782, 8.69–105.9, and 7.50–125.9 mg/kg, respectively. The mean concentrations of trace elements in four tissues descend in order of roots > leaves > stems > fruits. The abundances of trace elements varied in both soil and plant samples, which apparently occurred due to the variations of soil parent materials and the excessive use of agrochemicals for long-term banana cultivation. The soil exhibited a moderate to high degree of contamination with trace elements, and Cr, Pb, Zn, Cd, and As mainly originated from anthropogenic sources. Both non-cancer and cancer risks were perceived due to Cr and As exposure from the fruit tissue of banana plants in the study area.

Evaluation of Water Quality and the Potential Ecological and Health Risk in the Cajititlán Lagoon

Water security threatens the world's population, so the evaluation of the water quality of water bodies is one of the critical issues and is a current challenge to ensure the sustainability of ecosystems and human population.
 Objective: The aim is to estimate the physicochemical parameters and heavy metals of the water of the Cajititlán Lagoon during the period 2009-2023, to evaluate its water quality, ecological and health risks. The results will supply valuable information on water quality management and human health protection.
 Study Design: Ecological study, using water quality, pollution, ecological and health risk indices.
 Place and Duration of the Study: Cajititlán Lagoon during the period 2009-2023.
 Methodology: The water quality data of Lagoon Cajititlán were obtained through the State Water Commission of the government of the State of Jalisco. The analyses were performed monthly from 2009 to 2023. CWQI, WQI, NP, HPI, HEI, DC, PERI, HQ, HI, THI, CR and TCR indices were then calculated to find water quality and ecological and health risks.
 Results: The distribution of parameter concentration showed a drastic spatial variation, but not temporal. The TDS, Turbidity, pH, F, Al, As, Cr, Cu, Mn, Ni, Pb and Zn showed percentages above the CCME regulations, however most are within the NOM-001-SEMARNAT-2021. The heavy metals Al, Cr, Ni, Pb, Zn and As are those that present the % concentration of more than 100% with respect to the international standard. The remaining 14 parameters are within both national and international standards. Pearson's correlation analysis showed that most heavy metals have positive correlations with each other, except for Cr, Pb and Cu. Water quality according to WQI of 112 was categorized as poor-quality, while for CWQI all uses except livestock, water quality is poor (20-35). According to the NP index (0.19 to 670), heavy metal concentrations showed high contamination levels. The HPI index (89) showed moderate to elevated levels of heavy metal contamination. The HEI index showed levels <10, showing low pollution. The DC presented a value of 4, classified as a high degree of contamination. The PERI index showed that the ecological risk from heavy metals is high. Non-carcinogenic risk indices show that lagoon water is not suitable for drinking, and poses a high health risk via ingestion, while dermal contact poses no health risk to residential and recreational recipients. The results say that As would not pose a carcinogenic risk to residents and recreational receptors in different surface waters, while Cr may pose a slight carcinogenic risk to recreational receptors.
 Conclusions: According to the indices of water quality, ecological risk and health, the water quality of the Cajititlán Lagoon is poor, with a high degree of contamination and stands for ecological and health risks (non-carcinogenic).

Environmental impacts of industrial activities on floral coverage with special emphasis on detoxification enzyme activities in Cataglyphis savignyi as pollution biomarker

The present study investigates the environmental impact of industrial activities on floral coverage within the major industrial district of Borg El-Arab City, Egypt. Additionally, it aims to evaluate the detoxification enzymatic activity of Cataglyphis savignyi as a pollution biomarker. To achieve this objective, seasonal soil samples were collected from the studied sites to determine soil properties and heavy metal concentrations. Furthermore, a seasonal specimen of C. savignyi was collected to study the enzymatic activity of acetylcholinesterase (AChE) and glutathione-S-transferase (GST). Heavy metal contamination pollution indices were calculated, and fourteen plant species were identified at the investigated sites for four successive seasons from 2020 to 2021. The soil physicochemical parameters significantly varied in the industrial sites compared to the control site. The accumulation of heavy metal contamination in soil for investigated sites followed the order Ni > As > Pb > Hg. Calculated Cdeg and PLI for industrial 3 revealed a very high degree of contamination, attributed to increased industrial activity from the chemical and silicate factories that characterize this region. The current results highlight the inhibition of GST levels in C. savignyi at the industrial site compared to the control site. In contrast, AChE increases, which might be due to heavy metals enhancing acetylcholine activity at synapses. Consequently, the antioxidant enzymatic activities are useful as biomarkers for assessing and monitoring environmental contamination. In conclusion, this study underscores insects as potent biomarkers for heavy metal contamination, marking a significant advancement in environmental monitoring. These bioindicators offer crucial insights into the impacts of climate change and industrial pollution. The research reveals distinct plant diversity variations and higher heavy metal content in industrial sites, indicating pronounced contamination. Additionally, the study highlights altered enzyme activities in insects, emphasizing their utility as biomarkers for assessing environmental contamination. This work represents a substantial leap forward in comprehending the complex dynamics between contamination and ecological balance.

Environmental sampling for typhoidal Salmonellas in household and surface waters in Nepal identifies potential transmission pathways.

Salmonella Typhi and Salmonella Paratyphi, fecal-oral transmitted bacterium, have temporally and geographically heterogeneous pathways of transmission. Previous work in Kathmandu, Nepal implicated stone waterspouts as a dominant transmission pathway after 77% of samples tested positive for Salmonella Typhi and 70% for Salmonella Paratyphi. Due to a falling water table, these spouts no longer provide drinking water, but typhoid fever persists, and the question of the disease's dominant pathway of transmission remains unanswered. We used environmental surveillance to detect Salmonella Typhi and Salmonella Paratyphi A DNA from potential sources of transmission. We collected 370, 1L drinking water samples from a population-based random sample of households in the Kathmandu and Kavre Districts of Nepal between February and October 2019. Between November 2019 and July 2021, we collected 380, 50mL river water samples from 19 sentinel sites on a monthly interval along the rivers leading through the Kathmandu and Kavre Districts. We processed drinking water samples using a single qPCR and processed river water samples using differential centrifugation and qPCR at 0 and after 16 hours of liquid culture enrichment. A 3-cycle threshold (Ct) decrease of Salmonella Typhi or Salmonella Paratyphi, pre- and post-enrichment, was used as evidence of growth. We also performed structured observations of human-environment interactions to understand pathways of potential exposure. Among 370 drinking water samples, Salmonella Typhi was detected in 7 samples (1.8%) and Salmonella Paratyphi A was detected in 4 (1.0%) samples. Among 380 river water samples, Salmonella Typhi was detected in 171 (45%) and Salmonella Paratyphi A was detected in 152 (42%) samples. Samples located upstream of the Kathmandu city center were positive for Salmonella Typhi 12% of the time while samples from locations in and downstream were positive 58% and 67% of the time respectively. Individuals were observed bathing, washing clothes, and washing vegetables in the rivers. These results suggest that drinking water was not the dominant pathway of transmission of Salmonella Typhi and Salmonella Paratyphi A in the Kathmandu Valley in 2019. The high degree of river water contamination and its use for washing vegetables raises the possibility that river systems represent an important source of typhoid exposure in Kathmandu.

The link between lithospheric scale deformations and deep fluid emanations: Inferences from the Southeastern Carpathians, Romania

Understanding the formation, migration and emanation of deep CO2, H2O and noble gases (He–Ne) in deep-seated deformation settings is crucial to know the complex relationship between deep-originated fluids and lithospheric deformation. To gain a better insight into these phenomena, we studied the origin of H2O, CO2 and noble gases of gas-rich springs found in the Târgu Secuiesc Basin located in the southeasternmost part of the Carpathian-Pannonian region of Europe. This study area is one of the best natural examples to understand the connection between the deep sources of gas emanations and deep-seated deformation zones, providing an excellent analogue for regions with similar tectonic settings and fluid emanation properties. We studied the δ2H and δ18O stable isotopic ratios of the spring waters, and the δ13C, He and Ne stable isotopic ratio of the emanating CO2-rich gases dissolved in the mineral spring waters in Covasna town and its vicinity. Based on the δ2H, δ13C, δ18O stable isotopic ratios, the spring waters and the majority of the gases are released through two consecutive fluid infiltration events. The preservation of the metamorphic signal of the upwelling H2O is linked to the local groundwater flow and fault abundancy. Furthermore, the noble gas isotopic ratios show a high degree of atmospheric contamination in the dissolved water gasses that is most likely related to the local hydrogeology. Nevertheless, the elevated corrected helium stable isotopic ratios (Rc/Ra) of our filtered data suggest that part of the emanating gases have a potential upper mantle source component. Beneath the Southeastern Carpathians, mantle fluids can have multiple origin including the dehydration of the sinking slab hosting the Vrancea seismogenic zone, the local asthenospheric upwelling and the lithospheric mantle. The flux of the mantle fluids is enhanced by lithospheric scale deformation zones that also support the fluid inflow from the upper mantle into the lower crust. The upwelling CO2–H2O mantle fluids may induce the release of crustal fluids by shifting X(CO2) composition of the pore fluid and, consequently, initiating decarbonisation and devolatilization metamorphic reactions as a result of carbonate and hydrous mineral destabilisation in the crust. Based on the p-T-X(CO2) conditions of calc-silicates and the local low geotherm, we emphasise the importance of the upwelling fluids in the release and upward migration of further H2O and CO2 in the shallower lower and upper crust. We infer that migration of deep fluids may also play an important role in addition to temperature control on the generation of crustal fluids in deep-seated deformation zones.

Comprehensive health risk analysis of heavy metal pollution using water quality indices and Monte Carlo simulation in R software

Rapid urbanization, population growth, agricultural practices, and industrial activities have led to widespread groundwater contamination. This study evaluated heavy metal contamination in residential drinking water in Shiraz, Iran (2021). The analysis involved 80 groundwater samples collected across wet and dry seasons. Water quality was comprehensively assessed using several indices, including the heavy metals evaluation index (HEI), heavy metal pollution index (HPI), contamination degree (CD), and metal index (MI). Carcinogenic and non-carcinogenic risk assessments were conducted using deterministic and probabilistic approaches for exposed populations. In the non-carcinogenic risk assessment, the chronic daily intake (CDI), hazard quotient (HQ), and hazard index (HI) are employed. The precision of risk assessment was bolstered through the utilization of Monte Carlo simulation, executed using the R software platform. Based on the results, in both wet and dry seasons, Zinc (Zn) consistently demonstrates the highest mean concentration, followed by Manganese (Mn) and Chromium (Cr). During the wet and dry seasons, 25% and 40% of the regions exhibited high CD, respectively. According to non-carcinogenic risk assessment, Cr presents the highest CDI and HQ in children and adults, followed by Mn, As and HI values, indicating elevated risk for children. The highest carcinogenic risk was for Cr in adults, while the lowest was for Cd in children. The sensitivity analysis found that heavy metal concentration and ingestion rate significantly impact both carcinogenic and non-carcinogenic risks. These findings provide critical insights for shaping policy and allocating resources towards effectively managing heavy metal contamination in residential drinking water.

Identification of the nature of defects arising in the production of continuously cast pipe billets for the oil and gas industry

The paper presents the results of studies of defects that occur in the production of continuously cast pipe blanks for the oil and gas industry. It is shown that the use of the technology of continuous casting of pipe billets in comparison with the traditional methods of pouring liquid steel into a mold has a number of advantages, among which is the high productivity of the technological process. However, it was noted that in many cases, an abnormally high degree of contamination with non-metallic inclusions is observed in the structure of the steel of continuously cast pipe billets. It was revealed that the largest inclusions are oxides of silicon and manganese. On the surface of the pipes, there are defects in the form of oxide spots, near which there are large non-metallic inclusions. On the surface of the oxide spot, the presence of iron oxides in the form of scale is found, which is a consequence of the secondary oxidation of the metal by air oxygen. A mechanism for the development of oxide spots and decarburized strips in pipe billets has been determined, which consists in the formation of defects in the form of scratches and cracks on the surface before rolling. These defects during heating for rolling lead to the oxidation of the metal and the formation of scale on the surface of the pipe blanks. The results of experimental studies on the development of recommendations for improving the quality of the initial metal of seamless pipes for the oil and gas industry are presented. The study of the microstructure of steel and the assessment of its contamination with non-metallic inclusions were carried out on optical and electron microscopes, and the mechanical properties of pipe blanks were studied by standard methods

EVALUATION OF THE EFFECTS OF HEAVY METALS ON WATER FROM ILLEGAL CRUDE OIL REFINERIES: A CASE STUDY OF THREE SELECTED COMMUNITIES IN THE NIGER DELTA REGION, NIGERIA

In order to assess the levels of heavy metals and health concerns associated with the operations of illicit refineries in water, 15 surface water samples were taken from Okerenkoko, Peterou-Gbene, and Bille in the Niger Delta region of Nigeria. A number of heavy metal indices, including the Contamination Factor (Cf), Pollution Load Index (PLI), Modified Degree of Contamination (mCd), Ecological Risk Factor (Erf), and Geo Accumulation Index (Igeo), were successfully applied in the evaluation of heavy metal contamination in surface water using World Health Organization WHO (2011) and Nigerian Standard for Water Quality NSDWQ (2007) standards. Additional research from WHO and NSDWQ comparisons revealed that the majority of the investigated heavy metals were higher than permissble limits in comparison to the control site. Although the concentration of heavy metals in the aquatic habitats varies amongst the various communities in the area, according to the CV. Additionally, CV contends that there is a connection between the illicit refiners’ actions at the study site and the water chemistry changes that result in surface water contamination. According to data from the WHO and the NSDWQ, the majority of heavy metal concentration readings in the study sites exceeded the acceptable limits when compared to those in the control site. According to the results of heavy metals indices such as Cf and PLI, the surface water in the analyzed site ranges from very slightly contaminated to extremely contaminated. However, Erf and Igeo findings showed that human activities through illegal refiners increase heavy metal concentration, which results in a very high potential ecological risk associated with surface water. Additional mCd results demonstrated that in the studied sites, the surface water has a high degree of contamination. The findings suggest that surface water assessment is required to warn against a decline in water quality in the area.

Effects of soil metal(loid)s pollution on microbial activities and environmental risks in an abandoned chemical smelting site

Abandoned chemical smelting sites containing toxic substances can seriously threaten and pose a risk to the surrounding ecological environment. Soil samples were collected from different depths (0 to 13 m) and analyzed for metal(loid)s content and fractionation, as well as microbial activities. The potential ecological risk indices for the different soil depths (ordered from high to low) were: 1 m (D-1) > surface (S-0) > 5 m (D-5) > 13 m (D-13) > 9 m (D-9), ranging between 1840.65–13,089.62, and representing extremely high environmental risks, of which Cd (and probably not arsenic) contributed to the highest environmental risk. A modified combined pollution risk index (MCR) combining total content and mobile proportion of metal(loid)s, and relative toxicities, was used to evaluate the degree of contamination and potential environmental risks. For the near-surface samples (S-0 and D-1 layers), the MCR considered that As, Cd, Pb, Sb, and Zn achieved high and alarming degrees of contamination, whereas Fe, Mn, and Ti were negligible or low to moderate pollution degrees. Combined microcalorimetry and enzymatic activity measurements of contaminated soil samples were used to assess the microbial metabolic activity characteristics. Correlation analysis elucidated the relationship between metal(loid)s exchangeable fraction or content and microbial activity characteristics (p < 0.05). The microbial metabolic activity in the D-1 layer was low presumably due to heavy metal stress. Enzyme activity indicators and microcalorimetric growth rate (k) measurements were considered sensitive indicators to reflect the soil microbial activities in abandoned chemical smelting sites.

Comprehensive assessment of heavy metal contaminations in agricultural soil through Pollution Indices from a rapidly developing city of India

This study has been conducted for the comprehensive evaluation of heavy metals (HMs) contamination such as Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb in agricultural soils via pollution indices i.e. geoaccumulation index (Igeo), contamination degree (CD), pollution load index (PLI), potential ecological risk (PRI) etc. Assessment for the determination of ecological damage was caused by these HMs in different agro-ecosystems around metropolitan city Lucknow. For this, data has been taken from our previous study8 depicting significant enrichment of above mentioned HMs in agricultural soil present near riparian areas, brick kilns, waste dump sites etc. Our results indicated that soil samples collected from Gaughat (GAF) and Sitapur (SAF) showed very high degree of contamination (CD&gt;24). Further, pollution load index also reflected “very high” and “moderate to high” contamination with values 6.9075 and 3.3214 in these two sites respectively. Overall, Igeo values indicated moderate contamination with Mn and Ni metals and low contamination with Cr, Cu, Zn and Cd metals. However, Igeo with value 4.923 indicated extremely high degree of contamination due to Cd in Gaughat (GAF) soil. In the view of potential ecological risk index, GAF site poses a “very high” potential ecological risk while maximum sites pose “moderate” ecological risk. The ecological risk factor in agricultural soil was in the following descending order: Cd &gt; Ni &gt; Cu &gt; Pb &gt; Cr &gt; Mn &gt; Zn &gt; Fe. Cadmium predominantly contributes significant amount to the PRI of soil while Ni, Cu, Pb, Cr, Mn and Zn showed low ecological risk.

Evaluation of groundwater quality in the rural environment using geostatistical analysis and WebGIS methods in a Hungarian settlement, Báránd

The evaluation, visualization of environmental data from long-term monitoring, and making them accessible in a processed form in user-friendly interfaces on the Internet are important tasks of our time. The pollution of groundwater resources in settlements is a global phenomenon, the mitigation of which requires a number of environmental measures. In this study, water quality changes following the construction of a sewerage network were examined in the course of long-term monitoring between 2013 and 2022, during which 40 municipal groundwater wells were regularly sampled. Classifying the monitoring data into pollution categories based on water quality index (WQI) and degree of contamination index (Cd), a high degree of contamination was found in the period before the installation of the sewerage network (2014), as the majority of the wells were classified as contaminated and heavily contaminated. In the monitoring period following the installation of the sewerage network, a significant positive change was found in the case of most of the water chemical parameters tested (EC, NH4+, NO2−, NO3−, PO43−). Based on interpolated maps, it was found that an increasing part of the area shows satisfactory or good water quality. This was confirmed by the discriminant analysis as well, as it is possible to determine with an accuracy of 80.4% whether the given sample originates from the period before or after the installation of the sewerage network based on the given water chemical parameters. However, 8 years after setting up the sewerage network, the concentration of inorganic nitrogen forms and organic matter remains high, indicating that the accumulated pollutants in the area are still present. To understand the dynamics of purification processes, additional, long-term monitoring is necessary. Making these data available to members of the society can contribute to appropriate environmental measures and strategies.

BREAD ROPE SPOILAGE DEVELOPMENT

Rope spoilage of bread is produced by bacteria belonging to Bacillus genus. Insufficient cleaning of the wheat before the milling operation contributes to obtaining flour with a high degree of contamination with these bacteria which produce thermoresistant endospores and further maintain their viability in the baking process. After baking, thermoresistant endospores can pass into the vegetative form and can multiply, causing spoilage of bread, which is manifested by the occurrence of an unpleasant odour, and the core of the bread becomes sticky. In this study, samples of bread from second-grade wheat flour were obtained. The kinetics of bacterial growth in the core of the thermostated bread at 37 °C for 84 hours was determined. It was found that immediately after baking the degree of contamination of the bread core was 1.28·104 cfu/g, and after 40 hours of thermostating the degree of contamination of the bread core increased by 2.85 logarithmic cycles, at this bread sample were observed the first signs of the rope spoilage (unpleasant odour). Thus, bread obtained from highly contaminated flour can contain a very large number of bacteria belonging to Bacillus genus, having no signs of rope spoilage, and thus the consumption of this bread may be dangerous to the consumer’s health.

Pollution indices assessment of metal concentrations in Karabuk soil samples

Soil pollution refers to the contamination of soil by harmful substances that can have adverse effects on plant and animal life, it also negative affects the health-being of humans. The sources of soil pollution include industrial activities, agricultural practices, mining and transportation activities. The contaminants in soil can include heavy metals, pesticides, herbicides, fertilizers, petroleum products, and other chemicals. These contaminants can seep into the soil and accumulate over time, making the soil unsuitable for agriculture or other uses. Heavy metals are a significant concern in soil pollution due to their persistency and potential harm for living organisms. Therefore, it is essential to evaluate metal contamination in soil using ecological risk indices to protect human health. This assessment can help identify potential risks and enable effective management of contaminated sites. This study aimed to assess of the metal pollution levels, including Arsenic (As), Cobalt (Co), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn), in soil samples from Karabuk using various ecological risk indices. These indices included the geo-accumulation index (Igeo), enrichment factor (EF), contamination factor (CF), contamination degree (Cd), pollution load index (PLI), and potential ecological risk (PERI). Furthermore, statistical techniques such as correlation and factor analysis were employed to determine the underlying sources responsible for these metals. Based on the results of the Cd, PLI, and PERI, it was found that the soil at T7 exhibited a very high degree of contamination, was moderately to highly polluted, and posed a moderate ecological risk, respectively. The results of the pollution indices suggest that the sources of pollution in the Karabuk soil samples are anthropogenic, meaning they are a result of human activities like industrial processes and improper waste disposal.

Contamination and Ecological Risk Evaluation of Metals in Sediments from a Wetland of International Importance (Ramsar Site)

Wetlands are highly productive and diverse ecosystems providing home to thousands of organisms. These ecosystems reduce water pollution, sequester carbon, support livelihoods, and increase food security. However, these ecological functions are being impeded due to increased levels of metals in the environment. Therefore, the primary objective of this study was to evaluate the degree of metal contamination in the surface sediment of a wetland, Tanguar Haor, for the first time. The result demonstrated that the mean concentrations of Fe, Cu, Zn, As, Pb and Hg varied from 13140.39 to 45675, 40.07 to 46.29, 47.60 to 57.15, 18.89 to 35.23, 1.24 to 2.64, and 0.35 to 0.42, respectively. The concentration of As was found to be higher than the average shale value. The concentration of Cu (44.19 μg/g) and Hg (0.38 μ/g) was very close to the shale value (45 μg/g and 0.40 μg/g, respectively), indicating a moderate level of contamination. The contamination level was further evaluated by multi-indices, e.g., the contamination factor (CF), the enrichment factor (EF), and the geo-accumulation index (Igeo). The average EF values for As (115.41), Cu (57.68), and Hg (55.47) were &gt;50, indicating a high degree of contamination (extremely severe enrichment). However, CF values showed varied levels of pollution; for example, the majority of the area was only somewhat contaminated with As, Cu, and Hg, but less contaminated with Fe, Zn, and Pb. According to Igeo, sampling sites were found to be unpolluted or less polluted by heavy metals. Based on potential ecological risk assessment (PERI), the degree of risk from the six heavy metals decreased in the following sequence: As &gt; Cu &gt; Zn &gt; Pb &gt; Cr &gt; Ni. PERI values indicated the study area has been exposed to moderate risk to As and low risk to other metals. This study provides an opportunity for frequent monitoring of heavy metals in this ecologically critical environment, and thus curbing heavy metal pollution.

Ecotoxicological monitoring of potentially toxic elements contamination in Eucalyptus forest plantation subjected to long-term irrigation with recycled wastewater

Afforestation is an evergreen technology for restraining greenhouse gases (GHGs) emission and improving soil carbon sink in arid and semi-arid regions. Nonetheless, the long-term impact of woody forests irrigation using recycled wastewater resources remains inconclusive so far. For this purpose, the ecological risk benchmarks of potentially toxic elements (PTEs) were investigated on Eucalyptus forest plantation in order to gauge their bioavailability in the rhizospheric layer of Typic Torripsammentsoil and their accretion capacity in the biosphere. Water quality guidelines pointed to a moderate degree of restriction on use with elevated levels of PTEs. Notably, concentrations of As, B, Cd, Cr, Cu, Mn, Ni, V and Zn were above the permissible limits for irrigation. The geospatial mapping of PTEs concentration in soil pointed to elevated levels of most PTEs, particularly in the deforestated areas. Some of PTEs (Cd, Cu, Hg and Zn) showed values above the permissible limits. A spectrum of ecological risk indices showed considerable to high degree of contamination. Among PTEs, the water–soluble and exchangeable fractions showed high values of As, Cd and Hg (20.7, 17.2 and 11.0%, respectively). Sequential extraction showed variations among PTEs in their tendency to bind with different soil geochemical fractions: (i) carbonate (Cd, Zn and Cu), (ii) Fe–Mn oxides (Pb, Zn and Mn) and (iii) organic matter (B, Pb and Hg). Eight fungal species including Aspergillus flavus, Fusarium solani, Cephalosporimsp., Penicilliumsp., Rhizoctonia solani, Aspergillus niger, Botrytissp. and Verticilliumsp. were dominated in soil. Meanwhile, Agrobacteriumsp., phosphate solubilizing bacteria, nitrogen fixing bacteria and Escherichia coli were the dominant bacterial strains. Values of bioaccumulation index varied among PTEs, wherein B (5.15), Ni (1.98), Mn (1.62) and Cd (1.02) exhibited higher phytoextraction potentials. Other PTEs, however, exhibited values below 1.0 confirming their low phytoextraction potentials. Findings of this investigation, therefore, provide insights into biochemical signals of PTEs contamination in woody forest plantations and the urgent need to contextualize the large-scale utilization of recycled wastewater resources in such vulnerable areas.

Adherence to standard precautions by nursing professionals in Brazil during the COVID-19 pandemic: a cross-sectional study

Introduction: COVID-19 is an infectious disease caused by the SARS-CoV-2, which has a very high degree of contamination and confers patients and health professionals at risk. Thus, one wonders about the rate of adherence to standard precautions by nursing professionals from different contexts in the country. Aim: To identify adherence to Standard Precautions (SP) by nursing professionals who provided care during the COVID-19 pandemic and to verify the association between adherence to SP and sociodemographic and work characteristics. Outlining: Cross-sectional observational study, carried out with 493 nursing professionals working in nursing care in the five regions of Brazil. Data collection was carried out through Google Forms®, using social networks, the recruitment of participants took place between November 2020 and December 2021. Descriptive analysis was performed and the results presented by absolute and relative frequency. Pearson's chi-square test (X²) was used to verify the association between adherence to SP (≥ 75 points) and sociodemographic and work variables. Results: In the total sample, 353 (71.6%) professionals adhered and 140 (28.3%) did not. There was an association between age group (40 to 49 years) with adherence to SP in the total sample. Implications: Nursing professionals showed a deficit in adherence to SP, with younger people less likely to adhere, bringing great impacts to the health of professionals.

Sequential extraction of selected metals to assess their mobility, pollution status and health risk in roadside soil.

Assessment of the mobility and contamination of trace metals in the roadside soil is important to explore the environmental quality and potential risks to the public health. The contents of selected metals (Ca, Mg, Sr, K, Na, Li, Fe, Mn, Zn, Cu, Ag, Co, Ni, Cr, Cd and Pb) in the roadside soil collected from major highways/roadsides of Lahore, Pakistan were quantified employing mBCR sequential extraction. Among the metals, Ca, Sr and Na showed highest contribution in exchangeable fraction, Pb in the reducible fraction and K, Li, Fe, Ag, Ni, Cu and Cr in the residual fraction. However, Mg and Mn exhibited relatively higher contents in exchangeable and residual fractions while Cd, Co and Zn showed relatively higher concentration in all four fractions. Comparatively higher mobility and availability in the soil was shown by Ca followed by Sr, Pb, Na, Cd, Zn, Co, Mn, Cu, Ag and Ni. Principal component analysis demonstrated considerable anthropogenic contributions of the trace metals in the roadside soil. The pollution indices showed that the soil was heavily to extremely polluted by Cd and Ag, followed by significant to very high contamination for Co, Ni and Pb. The modified degree of contamination (4.60 and 3.99 in summer and winter, respectively) revealed an overall high degree of contamination. The health risk assessment revealed that the calculated risks were within the safe limit thereby indicating insignificant non-carcinogenic and carcinogenic heath risk to the populace.

Assessment of groundwater quality in Ranchi district, Jharkhand, India, using water evaluation indices and multivariate statistics.

Groundwater is the most abundant liquid freshwater on earth. Rapid urbanization in developing nations (like India) has led to increased groundwater withdrawal, adversely affecting the physicochemical characteristics. Ranchi district, Jharkhand, is a part of the smart city mission development plan of the government of India. Hence, to ensure safe and clean drinking water, it is necessary to assess groundwater quality and devise development plans. Seventeen physicochemical properties and metal(loid)s contents were analyzed to determine the groundwater quality. Various pollution indices such as water quality index (WQI), metal evaluation index (MI), heavy metal pollution index (HPI), and modified degree of contamination (mCd) are evaluated using arithmetic weighted value index and presented in a map using Arc GIS inverse distance weighting interpolation method. Chemometric analyses such as correlation, principal component, and cluster analysis were done to identify the source and determine the pollution state. A multiple linear regression model is employed to predict the impact of heavy metal and metalloid concentration on the WQI of the region. WQI shows that groundwater quality in Khelari (100.95) and Bundu (92.52) regions are highly degraded, whereas MI and HPI suggest that Ormanjhi (MI = 53.98) and Rahe (HPI = 109.20) are highly affected by metal contamination. The mCd suggests that Ormanjhi (97.15) has the highest degree of contamination. The contaminant sources were natural (geogenic processes) and anthropogenic (mining and industrial emissions). The high metal(loid)s concentration may soon result in groundwater quality degradation in the metal-affected regions.

Molecular characterization of waterborne protozoa in surface water and sediment in Brazil: a taxonomic survey of ciliated protozoa and their correlation with Giardia duodenalis and Cryptosporidium spp.

The detection of Giardia duodenalis and Cryptosporidium spp. was performed, along with the identification of the ciliated protozoa biodiversity, to evaluate the correlation between these protozoa in freshwater quality monitoring. Water and sediment samples from two sites in the Atibaia River (Campinas, São Paulo, Brazil) were collected monthly for 2years (n = 96). Pathogenic protozoa in water and sediment were detected by using immunomagnetic separation, followed by visualization by immunofluorescence assay (IFA). All positive aliquots in IFA were subjected to DNA extraction and subsequently nested PCR. Qualitative (in vivo observation and silver impregnation) and quantitative (in vivo enumeration) analyses were performed for the ciliated protozoa. Giardia cysts were detected in 62.5% of the surface water samples and Cryptosporidium spp. in 25.0%. In the sediment, cysts were detected in 35.4% samples and oocysts in 16.6%. A total of 57 samples positive for Giardia cysts were subjected to sequencing, 40 of which were harboring G. duodenalis (24 were characterized as sub-assemblage AII). For ciliated protozoa, 73 taxa belonging to 53 genera were identified over the period of the study. These results revealed a high degree of contamination by waterborne protozoa in the main water source which supplies drinking water for more than one million people in Campinas (São Paulo), highlighting the need for continuous monitoring of this catchment site. In addition, the present study provides important data regarding the sources of the water body degradation, i.e., fecal contamination of human origin, in addition to the survey of the ciliated protozoa.