Cr Values Research Articles

Environmental Assessment of Soils and Crops Based on Heavy Metal Risk Analysis in Southeastern China

Heavy metal pollution in soil–crop systems has attracted great attention globally, caused by rapid urbanization and intensive industrialization. The research aims to investigate the environmental quality of the agricultural production area in Taizhou City, a typical economic region that is along the Yangtze River in the Southeast of China. A total of 370 sampling sites were chosen, with 370 soil, rice (Oryza sativa L.) and wheat (Triticum aestivum L.) samples collected, respectively, for measuring and analyzing the status, spatial distribution and pollution level of different heavy metals. The mean values of soil Cr, Pb, Cd, As and Hg were 66.78, 32.88, 0.23, 8.16 and 0.16 mg/kg, which were lower than the risk control standard values (RCV). However, the mean values of Pb, Cd and Hg were 1.25-, 1.77- and 2-fold larger than their soil background values (SBV) due to the intensive anthropogenic activities. The average content of Cd in rice exceeded its food safety limiting values (FCV) by 0.05 mg/kg, and the average contents of Pb in rice and wheat both exceeded the relevant FSV by 0.42 and 0.186 mg/kg, respectively. In addition, the maximum As and Cr contents in rice and wheat could be 0.13, 0.46 mg/kg and 0.63, 3.5 mg/kg larger than the relative FCVs in certain areas. Most of the high-value areas of soil and crop heavy metals were mainly located in Xinghua City, Taixing City and Jiangyan District, which had a similar distribution pattern with local industries or anthropogenic activities. The heavy metal pollution in soils and crops was found to be inconsistent, as 8.94% of the arable land possessed lightly metal pollution, while 3.18% of the area of rice and 4.0% of the area of wheat suffered severe pollution, with excessive accumulation of Cr, Pb and Cd. Based on the heavy metal pollution assessment of soil–crop systems, approximately 83% of the study area possessed medium or higher environmental quality, which was preferable for agricultural production. Our results implied that the spatial distribution and pollution level of the heavy metals in soil–crop systems were significantly influenced by industrial activities, followed by agricultural sources, transportation emissions and so on. Therefore, continuous monitoring and source control of heavy metals, especially for Cr, Pb and Cd, should be conducted to ensure the regional environmental quality and food security.

Spatial Distribution of Heavy Metal Contamination in Road Dust Samples from an Urban Environment in Samsun, Türkiye.

Road dust is an environmental pollution indicator created by human activities for urban land use. This study aimed to determine the spatial distribution pattern and degree of trace metals in road dust samples collected from 5 different areas in Samsun city center. The trace metals of Mn, Co, Cd, Cr, Cu, Ni, Pb, and Zn are the most examined contaminants in road dust because their hot-spot areas were mainly associated with high traffic density. Factors governing potential contamination index range values of Co, Cr, and Ni were 0.34-0.62, 0.23-0.78, and 0.24-0.48 as the lowest contamination. However, potential contamination index values of Cu, Pb, and Zn in the main road site were 1.80, 2.32, and 2.84 suggesting that relatively high values were uncontaminated to moderately. Pollution assessment methods were applied to toxic metals and revealed that Samsun city had been affected as uncontaminated to moderately contaminated by anthropogenic emission of heavy metals.

Metal Exposure in Arica, Chile: Examining Toxic Elements.

Bioaccumulation of toxic metals in the population is associated with adverse health effects. Although some elements are essential for humans, high levels of exposure can be dangerous. To describe the levels of Inorganic Arsenic (AsIn), Cadmium (Cd), Chromium (Cr), and Mercury (Hg) in urine, and Lead (Pb) in blood in the population of Arica, Chile. Descriptive study. Beneficiaries of the Health Surveillance Program of Law 20.590 in sites of higher risk of exposure in the commune of Arica were considered eligible. The results of biological samples to measure their concentrations of AsIn, Cd, Cr, Hg in urine, and Pb in blood between August 2016 and May 2021 are described. 9520 samples from a population with a mean age of 40.5 years were studied. 4.21% of the adult population and 6.57% of the children had AsIn values above 35 μg/L, while at least 95 % of the total samples had levels below 33 μg/L. At least 90 % of the samples had Cd levels below 1.1 μg/L, and 8.44 % had Cd levels above 2 μg/L, higher in males (11.67%). There were no values above the reference in children. 99.77% and 99.33% had Cr and Pb values below the reference limit, respectively (using the lowest reference range established by Chile Ministry of Health (MINSAL) < 5 μg/L). Children did not present risk values for Cr, and 0.16% presented Pb concentrations between 5-10 μg/dL. All samples presented Hg concentrations below risk levels (< 10 μg/L). The results of this study suggest that a small percentage of the samples analyzed in the beneficiary population of Arica register metal concentration levels above national reference levels established by MINSAL, mainly AsIn, Cd, and Pb. It is essential to continue biomonitoring to reduce and prevent exposure to these metals, which can have harmful effects on human health.

Supplier Selection Based on Green Procurement of Agricultural Commodities of Cassava: Environmental Perspective From Jember Regency

Industrial developments and increasing consumer concern for the environment and the issue of environmentally sound industrial concepts have forced the industry to adjust the concept of green industries in every business, including in procurement, which is better known as green procurement. Supplier selection is an important decision-making problem to get suppliers who can increase the company's competitiveness. This research was conducted in Jember regency to evaluate and select cassava suppliers based on green procurement using the AHP method. The criteria used are 6 criteria, namely quality, technology capability, pollution control, environment management, green product, and green competence. Each criterion has sub-criteria between 3 or 4 sub-criteria. The number of sub criteria is used to determine the RI value. The RI value is used to calculate the CR value of each criterion. The results of data processing show that the highest CR value is in the technology capability criteria and the lowest CR value is in environment management. The highest hierarchical criterion value for environmental management criteria is 0.273, because the selection of cassava suppliers can be expected to pay attention to environmentally sound controls.

Allometric-kinetic model predictions of radionuclide dynamics across turtle taxa

Chelonians (turtles, tortoises, and sea turtles; hereafter, turtles) inhabit a wide variety of ecosystems that are currently, or have the potential in the future to become, radioactively contaminated. Because they are long-lived, turtles may uniquely accumulate significant amounts of the radionuclides, especially those with long half-lives and are less environmentally mobile. Further, turtle shells are covered by scutes made of keratin. For many turtle taxa, each year, keratin grows sequentially creating annual growth rings or layers. Theoretically, analysis of these scute layers for radionuclides could provide a history of the radioactivity levels in the environment, yet there are few previously published studies focused on the dynamics of radionuclide intake in turtles. Using established biochemical and ecological principles, we developed an allometric-kinetic model to establish relationships between the radionuclide concentrations in turtles and the environment they inhabit. Specifically, we calculated Concentration Ratios (CRs – ratio of radionuclide concentration in the turtle divided by the concentration in the soil, sediment, or water) for long-lived radionuclides of uranium and plutonium for freshwater turtles, tortoises, and sea turtles. These CRs allowed prediction of environmental concentrations based on measured concentrations within turtles or vice-versa. We validated model-calculated CR values through comparison with published CR values for representative organisms, and the uncertainty in each of the model parameters was propagated through the CR calculation using Monte Carlo techniques. Results show an accuracy within a factor of three for most CR comparisons though the difference for plutonium was larger with a CR ratio of about 200 times for sea turtles, driven largely by the uncertainty of the solubility of plutonium in sea water.

Seasonal Variations in the Trace Elements and Mineral Profiles of the Bivalve Species, Mytilus galloprovincialis, Chamelea gallina and Donax trunculus, and Human Health Risk Assessment.

This study aimed to provide data on selected toxic (Cd, Pb and Ni), essential (Cr, Cu, Fe, Mn and Zn) and microelement (Na, K, Ca and Mg) concentrations in edible tissues of the Mediterranean mussel (Mytilus galloprovincialis), striped venus clam (Chamelea gallina) and the wedge clam (Donax trunculus). Samples were collected from the Black Sea (Bulgaria) four times over, a period of one year (2022). In comparison with the maximum permissible levels set by the EU and USFDA, all elemental concentration found in the bivalve species were lower than the prescribed limits. An estimation of the dietary metal intake through calculation of the target hazard quotients (THQ), hazard index (HI) and target risk (TR) was performed. The target hazard quotient (THQ) for individual metal and HI for combined metals were lower than 1, indicating no health risk for consumers due to the intake of either individual element or combined ones. The target risk value for toxic inorganic Pb and Cr was below 10-6, indicating no carcinogenic risk. According to these results, the consumption of these bivalve species is completely safe for human health.

Assessment of occupational health risk due to inhalation of chemical compounds in an aircraft maintenance, repair, and overhaul company

This study was conducted in an aircraft maintenance, repair, and overhaul (MRO) company in 2021 to identify the extent of occupational exposures and quantitative assessment of the health risk due to inhalation of chemical compounds. According to the inspection of different parts of this company, heavy metals including Co, Cd, Ni, Pb, Cr(VI), and Mn and organic compounds including benzene, toluene, ethylbenzene, xylene (BTEX), and methyl ethyl ketone (MEK) were selected for health risk assessment. In total, the air in the inhalation area of active workers was sampled in 51 workstations. Measurement of the above pollutants showed that the average occupational exposure to Cd, Pb, and all organic compounds fell within the acceptable range of occupational exposure standard, while the measured values for Co, Ni, Mn, and Cr(VI) exceeded the standard limit. According to calculations, the highest carcinogenic risk (CR) was seen in the plating (airplane) workshop for exposure to Cr(VI) (7.58E-01), and the lowest CR was observed in the electronic workshop for exposure to Pb (7.75E-08). The highest non-carcinogenic hazard (HQ) was found in the welding workshop for exposure to Co (1.00E + 04), while the lowest HQ was related to toluene in the fabrication workshop (9.10E-03). Considering the high rate of exposure indicators, CR and HQ exceeded the standards set by the American Environmental Protection Agency (EPA) in most workshops. Accordingly, company managers should take the necessary measures to reduce the vulnerability of individuals working in areas with unacceptable CR and HQ.

Environmental geochemical baseline determination and pollution assessment of heavy metals in farmland soil of typical coal-based cities: A case study of Suzhou City in Anhui Province, China

Soil is the foundation of agricultural green development and human survival; the study of local environmental geochemical baselines can guide soil management and ensure the safe use of soil. In this study, a total of 100 shallow farmland soil samples were collected in each township of Yongqiao District, Suzhou City, Anhui Province, China. Herein, the contents of 10 heavy metal elements including As, Hg, Cd, Pb, Cr, Cu, Mn, Ni, Zn and Fe were determined. In addition, the geochemical baseline of heavy metals was calculated based on the relative cumulative frequency curve method, and the soil pollution status was evaluated. The results show that the average contents of As, Hg, Cd, Cu, Mn and Zn exceeded the soil background values of Anhui Province by 3.82%–64.74% (1.04–1.65 times), meanwhile, the average contents of Pb and Cr were lower than the soil background values of Anhui Province. The average contents of Cd, Cr, Cu, Mn and Ni exceeded the Chinese soil background values by 1.61%–64.74% (0.98–1.65 times). The geochemical baseline values of As, Hg, Cd, Pb, Cr, Cu, Mn, Ni, Zn and Fe were 9.585 mg/kg, 0.028 mg/kg, 0.112 mg/kg, 21.59 mg/kg, 53.66 mg/kg, 19.31 mg/kg, 543.8 mg/kg, 24.93 mg/kg, 50.57 mg/kg and 2.654%, respectively. The pollution assessment results also showed that most of the farmland soil samples in the study area were non-polluting or slightly polluted based on geochemical baselines. Hg and Cu in a few samples were moderately polluted, and Cd in only one sample was moderately intensely polluted. Combined with the distribution of pollution and field investigation, it is considered that Hg comes from atmospheric deposition and agricultural non-point source pollution of industrial pollution. Cu comes from animal husbandry and agricultural pollution. Meanwhile, Cd is related to natural sources, wood processing and agricultural fertiliser application. The study demonstrated that the calculation of soil geochemical background value should take full account of the differences between the various regions, combined with the current state, particularly the pre-consideration of the distribution of elements or pollutants. Then, reasonably select the evaluation standard value so that the evaluation results can truly reflect the state of soil pollution.

Compression of Bio-Signals Using Block-Based Haar Wavelet Transform and COVIDOA for IoMT Systems.

Bio-signals are the essential data that smart healthcare systems require for diagnosing and treating common diseases. However, the amount of these signals that need to be processed and analyzed by healthcare systems is huge. Dealing with such a vast amount of data presents difficulties, such as the need for high storage and transmission capabilities. In addition, retaining the most useful clinical information in the input signal is essential while applying compression. This paper proposes an algorithm for the efficient compression of bio-signals for IoMT applications. This algorithm extracts the features of the input signal using block-based HWT and then selects the most important features for reconstruction using the novel COVIDOA. We utilized two different public datasets for evaluation: MIT-BIH arrhythmia and EEG Motor Movement/Imagery, for ECG and EEG signals, respectively. The proposed algorithm's average values for CR, PRD, NCC, and QS are 18.06, 0.2470, 0.9467, and 85.366 for ECG signals and 12.6668, 0.4014, 0.9187, and 32.4809 for EEG signals. Further, the proposed algorithm shows its efficiency over other existing techniques regarding processing time. Experiments show that the proposed method successfully achieved a high CR while maintaining an excellent level of signal reconstruction in addition to its reduced processing time compared with the existing techniques.

Redox Changes during the Past 100 ka in the Deeper Eastern Arabian Sea: A Study Based on Trace Elements and Multivariate Statistical Analysis

The temporal distribution of trace elements in a sediment core (SK117/GC-08) indicates minor changes in oxygenation during the last 100 kilo years in the bottom waters of the deeper eastern Arabian Sea. The high values of Mn, Co, Cu, Mn/Al, Co/Al, Cu/Al, V/Cr, and V/(V + Ni) in the sediments during interglacials and interstitials collectively indicate oxic conditions during warm periods. The high values of Cr, Ni, V, Mo, Cr/Al, Ni/Al, and Ni/Co in sediments during glacials and stadials collectively indicate dysoxic to suboxic conditions during the colder last glacial maximum and during the entire marine isotope stage two. The bottom waters have never experienced anoxic conditions. Multivariate statistics showed the attribution of the trace elements in two factors: cluster 1 (Co, Cu, Mn) was enriched during oxic conditions and cluster 2 (Cr, Mo, Ni, V) was enriched during dysoxic to suboxic conditions. Oxygenation conditions are mainly driven by variations in monsoon-controlled surface water productivity and changes in the flux of circumpolar deep water. The dysoxic to suboxic bottom water conditions developed at the core location during colder climates are very well synchronised with an increased organic matter flux. The main factor that controls the accumulation of the organic-rich sediments in the eastern Arabian Sea during a glacial is the increase in the supply of organic matter from increased primary productivity in the surface waters, controlled by winter monsoon winds, and localized convective mixing. During warmer interglacials and interstadials, the core location has remained well ventilated.

A Carbonized Zeolite/Chitosan Composite as an Adsorbent for Copper (II) and Chromium (VI) Removal from Water.

To address Cu(II) and Cr(VI) water pollution, a carbonized zeolite/chitosan (C-ZLCH) composite adsorbent was produced via pyrolysis at 500 °C for two hours. C-ZLCH was characterized using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and zeta potential measurements. The batch experiments were performed by varying the initial pH, concentration, and contact time. The optimal pH values for Cu(II) and Cr(VI) were 8.1 and 9.6, respectively. The highest adsorption capacities for Cu(II) and Cr(VI) were 111.35 mg/g at 60 min and 104.75 mg/g at 90 min, respectively. The effects of chemicals such as sodium (Na+), glucose, ammonium (NH4+), and acid red 88 (AR88) were also studied. Statistical analysis showed that sodium had no significant effect on Cu(II) removal, in contrast to Cr(VI) removal. However, there was a significant effect of the presence of glucose, ammonium, and AR88 on both Cu(II) and Cr(VI) removal. The adsorption isotherm and kinetic models were fitted using Langmuir and pseudo-second-order models for Cu(II) and Cr(VI), respectively.

The Impact of the Application of PSAK 72 on the Financial Performance of Property Companies

This study aims to analyze revenue recognition based on PSAK 72 and its impact on the financial performance of property companies listed on the Indonesia Stock Exchange in 2019. The sample companies are 18, but only five implemented PSAK 72 in 2019. The five companies jointly implemented PSAK 71 on January 1, 2020, thus causing retrospective adjustments in 2018 and 2019 in its retained earnings that will have an impact on the statement of financial position and company performance. The method in this research uses the descriptive qualitative method. The data analysis technique used analyzes the five steps of the revenue recognition procedure based on PSAK 72. The results of this study show differences in the application of revenue recognition based on PSAK 72 with the previous standard resulting in changes in the value of revenue originating from customer contracts. Seen in each company's CR value has decreased, and the DTA value has increased for the five companies. At NPM, two companies experienced a decline due to the implementation of PSAK 72. However, the NPM at three companies has actually experienced an increase.

The Source Apportionment of Heavy Metals in Surface Dust in the Main District Bus Stops of Tianshui City Based on the Positive Matrix Factorization Model and Geo-Statistics

For the pollution assessment and quantitative source apportionment of heavy metals in surface dust, a total of 52 surface dust samples were collected from bus stops in Tianshui City. The geoaccumulation index (Igeo) and potential ecological risk index (RI) were used to analyze the pollution levels caused by heavy metals. The Positive Matrix Factorization (PMF) of the receptor modeling and geo-statistics were employed to analyze the source of the heavy metals. The results were as follows. ① Except for Mn, Co and V, the mean concentrations of other heavy metals have exceeded the local background value of Gansu. The percentage of excessive concentrations of Cu, Zn, Sr, Ba and Pb in the samples was 100%, and that of Cr, Ni and As were 96.15%, 94.23%, and 96.15%, respectively. ② Semivariogram model fitting showed that the block-based coefficients of Cu, Zn, Sr, Ba, Pb, Cr, Ni, and As were between 0.25 and 0.75, indicating that they were mainly affected by human factors. The high values of Pb, Zn, Ni and As were mainly distributed in the eastern part of the study area, and the high values of Cu, Sr, Ba and Cr were distributed in a spot-like pattern in the study area. ③ The Igeo results showed that As, Cu, Zn, and Pb were the main contamination factors, and the optimized RI showed that the heavy metals were the overall ecological risk of intensity, among which Pb, As and Cu were the main ecological factors and should be taken as the priority control objects. ④ Based on the PMF, there are four main sources of eleven heavy metals. V, Mn, and Co were attributed to natural sources, accounting for 18.33%; Cu, Sr, and Ba were from mixed sources of pollution from transportation and industrial alloy manufacturing, accounting for 26.99%; Cr and Ni were from sources of construction waste pollution, accounting for 17.17%, As, Zn and Pb were mainly produced by coal-traffic mixed pollution emissions, accounting for 37.52%. Overall, the study area was dominated by coal-traffic emissions.

Carcinogenic and non-carcinogenic risk assessment of exposure to trace elements in groundwater resources of Sari city, Iran.

The daily intake of trace elements through water resources and their adverse health effects is a critical issue. The purpose of this research was to assess the carcinogenic and non-carcinogenic risks of exposure to iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), chromium (Cr), lead (Pb), and arsenic (As) in groundwater resources of Sari city, Iran. The concentrations of the trace elements in a total number of 66 samples from the groundwater sources were measured using inductively coupled plasma mass spectrometry (ICP-MS). The hazard index (HI) levels of exposure to the trace elements from the groundwater sources for adults, teenagers, and children were 0.65, 0.83, and 1.08, respectively. The carcinogenic risk values of Cr and As in the groundwater sources for children, teenagers, and adults were 0.0001, 0.00009, 0.00007, 0.0003, 0.0002, and 0.0001, respectively, causing a total carcinogenic risk value higher than the acceptable range, and removing Cr and As from the groundwater resources is recommended for safe community water supply.

Nutritional profile and heavy metal contamination of nursery, grower, and finisher feeds of tilapia (Oreochromis niloticus) in Bangladesh

Tilapia, the third most cultured fish, is a part of the daily diet of more than 50% of the population of Bangladesh. Thus, adequate nutrition and toxic metal-free tilapia fish feeds are the prerequisites of sustainable aquaculture. The present study was carried out to investigate the nutritional profile and heavy metal pollution in nursery, grower, and finisher types of feeds of tilapia commercially available in Bangladesh. The proximate composition (moisture, protein, lipid, ash, crude fibre, and carbohydrate), mineral nutrients, fatty acid profile, and heavy metals (Pb, Cd, Cr, Ni, Cu, and Zn) of feed samples were assessed. Low protein content and the absence of essential fatty acids mark the feeds as low-quality diets. A significant amount of trace metals were also detected in the feeds, posing a direct threat to the health of the fish and, ultimately, to consumers. The results revealed the highest Zn concentration in all tilapia feed samples. The descending order of heavy metal concentrations was identified as Zn>Ni>Pb>Cu>Cr in nursery feeds, Zn>Cu>Cr in grower feeds, and Zn>Ni>Cu>Cr>Cd in finisher feeds. Pb and Cr values were higher than the recommended values set by FAO. Therefore, strong monitoring is recommended to ensure the optimum quality and safety feeds.

Contamination and health risk assessment of potentially toxic elements in soils of different kinds of land use in Lithuania

Using the case of five different kinds of land use from different territories of Lithuania, this study assesses the level of contamination and human health risk assessment of arsenic (As), and heavy metals (HMs) such as cadmium (Cd), copper (Cu), zinc (Zn) and chromium (Cr) in the surface soil of the study areas. Geo-accumulation index (Igeo) analysis indicated that heavy Cd contamination occurred in agricultural territory (AT), while for As, no contamination to mild contamination occurred in all territories. For living territory (LT), green territory (GT) and technical territory (TT), Igeo readings for Cu showed no pollution to moderate pollution, while there was no pollution for natural territory (NT) and AT. For AT, there is no contamination from Zn or Cr. By contrast, Igeo values for Zn and Cu represent minimal to no pollution in the remaining territories. As in LT and Cd in AT, two of the HMs discovered, were deemed to be of medium risk, whereas other components fell into the permitted range. Among three different routes to exposure, it was discovered that the ingestion pathway was the main health risk. The Hazard quotient (HQ) and hazard index (HI) values for As, Cd, Cu, Zn, and Cr were lower than the suggested limit (HI = 1), indicating minimal non-carcinogenic risk to inhabitants in the study regions. The carcinogenic risk values for As (1.12E-04 children), Cd (2.20E-04 children), and Cr (2.35E-04 children) in AT pose a risk to children’s health when ingested. The GT’s carcinogenic readings for Cr (1.02 E+00 adult), put adults at risk of developing cancer, whereas As (1.89E-04) and Cr (2.28E-04) in LT put children at risk of cancer and for TT, both adults and children were at risk due to Cr’s higher carcinogenic values (1.93E-04 for adults and 5.21E-04 for children).

Estimation of phytoextraction potential of selected halophytes for accumulation of heavy metals from wetland saline soil

The phytoremediation is a significant natural clean-up process for removal of heavy metals from wetland saline soils (WS) for the sustainable environmental pollution control. Therefore, the phytoremediation potential of Typha domingensis (southern cattail) and Phragmites australis (common reed) has been evaluated for absorption and accumulation of salts and heavy metals growing at two sites of WS samples coded as BS1 and BS2 (“BS” the soil that is not adjoining to root of plants) in Hyderabad Sindh, Pakistan. The three parts (root, stems, and leaves) of both Plants were obtained from several of locations oxidized the matrices of each part of plants and the corresponding soil samples using acid mixture. A variety of techniques were used to identify the metals by atomic absorption spectrometry. The average values of heavy metals, Co, Cd, Cr, Cu, Pb, and Zn in BS1 and BS2 were found to be (8.53, 14.4, 8.88, 64.3, 13.3, and 142) and (12.4, 18.2, 13.6, 89.4, 14.4, and 124) µg/g, respectively. The data of bioconcentration (BCF) and translocation factors (TF) of the research showed that the studied halophytes showed a high accumulation potential (> 1) for heavy metals from WS. The metal content in plants and rhizospheric soil have a strong relationship (p < 0.01). The screening data based on classical methods and GC–MS indicated that the studied phyto extractants have many phytochemicals. These phytochemicals may have the capability to accumulate heavy metals from contaminated soils. The roots and their rhizospheric soil (RS1 and RS2) have a highly significant relationship of accumulation potential with the selected heavy metals (RS is soil adjoining to roots of plants) (p < 0.01). These halophytes are able to remove heavy metals directly from salty metal-contaminated soil in wetland environments.

Contamination and risk surveillance of potentially toxic elements in different land-use urban soils of Osogbo, Southwestern Nigeria.

The concentrations of potentially toxic elements (PTEs) and their contamination indices were determined in urban soil from five different land-use zones, namely municipal solid waste landfill (MWL), industrial area (INA), heavy traffic area (TRA), residential area with commercial activities (RCA), and farmland (FAL) in Osogbo Metropolis. Ecological and human health risk assessments were also evaluated. Based on the average concentrations, the highest values of As, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn were found at INA, while the maximum concentrations of Ba, Cd, and Co were observed at MWL. The average enrichment factor (EF) values of Cd, Cu, Pb, and Zn showed very high to extremely high enrichment in the soils of INA, MWL, TRA, and RCA, while the EF values of Ba, Co, Cr, Fe, Ni, and V were significantly to moderately enriched in the aforementioned land-use zones. This trend was consistent with the average contamination factor (Cf) values of Cd, Cu, Pb, and Zn, which indicated considerable to very high contamination at INA, MWL, TRA, and RCA. However, Cf values of Ba, Co, Cr, Fe, Ni, and V had moderate contamination variously at the different land-use zones. Furthermore, the potential ecological risk factor (Eri) values for all the PTEs were < 40, which indicated low Eri, except for Cd and to some extent Pb. The Eri value of Cd was high to very high at MWL, INA, TRA, and RCA, and low at FAL, while Eri of Pb was only moderate at INA. Assessment of health quotient (HQ) of non-carcinogenic health risks was within acceptable limit (< 1) for most of the PTEs in the different zones for adults and children, except the maximum HQ value of Pb at INA (HQ = 1.0), which was beyond the acceptable limit for children. The carcinogenic risk was within the acceptable limit (1.0 × 10-6) in all the zones, except INA. This may pose health challenges to children in the vicinity of the pollution sources. Continuous monitoring of PTEs to reduce exposure to PTE should be considered.

Concentration of Toxic Heavy Metals and Phytochemicals in a Medicinal Plant (Asclepias fruticosa) Collected Around Mining Areas in Brits, Pretoria

The use of African traditional medicine in rural and peri-urban areas is common due to its affordability and accessibility. The study aimed to determine the levels of toxic heavy metals in the medicinal plant (Asclepias fruticosa) samples collected around three mining areas in Brits using ICP-OES. The phytochemical screening analysis was done to indicate the absence or presence of different phytochemicals in the medicinal plant. The results of the qualitative phytochemical analysis indicated the presence of flavonoids, alkaloids, proteins, and carbohydrates in Asclepias fruticosa collected from all the mining areas. The results of the heavy metals showed that the mean highest concentration for all the heavy metals was recorded for Mn from the leaves of the medicinal plants. The trend in the heavy metals accumulation was roots &gt; leaves &gt; stems from all the sites, and the differences were significant (p &lt; 0.05). The range of heavy metals in the plant was in the range Mn (12.33 ± 2.31-85.33 ± 51.07 μg.g-1), Zn (10.67 ± 0.58-60.33 ± 0.56 μg.g-1), Cr (3.43 ± 0.06 -34.90 ± 0.10 μg.g-1), Cu (8.67 ± 0.12-18.8 ± 1.57 μg.g-1), Ni (5.67 ± 0.12-23.23 ± 1.7 μg.g-1) and Pb (0.53 ± 0.013-1.59 ± 0.15 μg.g-1). The values of the heavy metals Cr, Zn, and Ni in the plant exceeded the recommended limits set by WHO for human consumption. Heavy metals in the medicinal plant were accumulated in the roots and not translocated to the stems and leaves. It is therefore recommended that communities staying around the mines should be discouraged from picking and using medicinal plants growing around the mines and should be educated on the safety of medicinal plants growing around the mines.

Abstract Number ‐ 57: Investigation on Hemodynamic Force Related to Thin‐walled Regions in Intracranial Aneurysm by Using CFD

Introduction Although thin‐walled regions (TWRs) in an intracranial aneurysm have a risk of rupture due to contact with surgical instruments, imaging modalities cannot accurately evaluate the thickness of aneurysm walls. The surgical operation will be able to perform safely by identifying the location of TWRs before the treatment. In previous studies, computational fluid dynamics (CFD) has been used to investigate the relationship between hemodynamics and TWRs. However, a quantitative method has not been employed to evaluate the location of TWRs. This study aims to clarify the relationship between hemodynamics and TWRs by comparing the results of CFD analysis with quantitatively defined TWRs. Methods We identified 70 aneurysms (MCA: 48, ACA: 20, ICA: 2) treated with craniotomy and clipping. CFD analysis was conducted to evaluate the pressure difference (PD), wall shear stress (WSS), and wall shear stress divergence (WSSD) on the aneurysm wall. High regions were defined as the regions with values above the 90th percentile for each parameter, and Low regions were defined as the regions with values below the 10th percentile for each parameter. In this study, 4 regions (HighPD, HighWSS, LowWSS, and HighWSSD) and 6 regions obtained by combining two of these regions were defined as regions of interest (RoI). Because TWRs generally indicate intense red, the comprehensive red value (cR value) was defined by using the RGB color model to evaluate the intensity of redness. The cR value was calculated for each pixel of the intraoperative images, and TWRs were defined using the cR value. Comparing the results of CFD analysis and identified TWRs, the percentage of the area of TWRs in RoI was calculated as the occupancy ratio. Results Table 1 shows the mean occupancy ratio for each defined RoI. The mean occupancy ratio in RoI by a single parameter is higher in the order of HighPD, HighWSSD, HighWSS, and LowWSS regions. In HighPD regions, which show the highest occupancy ratio, the impingement flow to the aneurysm wall is considered to make the aneurysm wall thinner. In HighWSSD regions, the aneurysm wall seems to have thinned due to the tensile force along the wall surface caused by blood flow. The mean occupancy ratio of RoI obtained by the combination of two regions is lower than that of HighPD regions. However, in some cases, TWRs that could not be identified by HighPD regions can be detected by HighPD or HighWSSD regions. Conclusions The mean occupancy ratio for RoI was higher in the order of HighPD, HighWSSD, HighWSS, and LowWSS regions. Therefore, it was suggested that these hemodynamic parameters are related to TWRs. Furthermore, in some cases, TWRs that the RoI of a single parameter could not identify can be detected using RoI obtained by the combination of two parameters.