Fe Content Research Articles

Early-stage growth and elemental composition patterns of Brassica napus L. in response to Cd–Zn contamination

Soil contamination caused by the presence of Cd and the excess amount of Zn is a widespread concern in agricultural areas, posing significant risks to the growth and development of crops. In this paper, the early-stage development and metal (Cd and Zn) accumulation potential of rapeseed (Brassica napus L.) grown under different metal application schemes were assessed by determining radicle and hypocotyl length and the micro- and macro elemental composition of plantlets after 24, 72, and 120 h. The results indicated that the single and co-application of Cd and Zn significantly reduced the radicle and hypocotyl lengths. Accumulation intensity for Cd and Zn was affected by Cd and the combination of Cd and Zn in the solution, respectively. In addition, both metals significantly influenced the tissue Mn and had a minor effect on Cu and Fe concentrations. Both Cd and Zn significantly affected macro element concentrations by decreasing tissue Ca and influencing K and Mg concentrations in a dose- and exposure time-dependent manner. These findings specify the short-term and support the long-term use of rapeseed in remediation processes. However, interactions of metals are crucial in determining the concentration patterns in tissues, which deserves more attention in future investigations.

The Effect of Integrated Nutrient Management on Growth, Yield Attributes and Yield of Transplanted Rice under Irrigated Condition (Oryza sativa L.)

The present investigation was carried out in kharif season 2022-23 at Agronomy Research Farm of Chandra Bhanu Gupta Krishi Snatakottar Mahavidyalaya, Bakshi ka Talab, Lucknow (U.P). The 8 treatments comprised of T1- RDF(IF), T2- 100% RDF+25 kg ha-1 ZnSO4 (B), T3-100% RDF+2 foliar spray of ZnSO4, T4- RDF+50 kg ha-1 FeSO4 (B),T5-100% RDF+ZnSO4 25 kg ha-1 (B) + FeSO4 @ 50 kg ha-1 (B), T6- 75% RDF (IF)+25% RDN (FYM), T7- 50% RDF (IF)+50% RDN (FYM),T8-100% RDF through FYM were laid out in Randomized Block Design (RBD). The soil was silty-loam texture with slightly alkaline pH 8.1, organic carbon 0.70 %, available nitrogen 270.00 kg ha-1, available phosphorus 27.0 kg ha-1, and available potash 262.0 kg ha-1 during 2022-2023. The values of growth contributing characters viz., plant height (cm), number of tillers per m2 (439.73), dry matter accumulation (g m -2 ) (829.62), at harvest and significantly highest (6.33) leaf area index (LAI) was recorded under 100% RDF + 2 foliar spray of ZnSO4 and yield attributes and yield like number of effective tillers per m-2 (200.66), panicles weight (g)(4.51), length of panicle (cm) (28.33), number of grains panicle-1 (175.33), test weight (g) (29.10), grain yield (47.85), straw yield (q ha-1 ) (64.75) of rice were significantly higher under T3- 100% RDF + 2 foliar spray of ZnSO4 compared to other treatment. The nitrogen content (%), and its uptake (kg ha-1), and protein content (%), and its production (kg ha-1) in grain and straw was significantly higher under T3-100% RDF + 2 foliar spray of ZnSO4. The Fe and Zn content (mg kg-1) and its uptake (kg ha-1) in grain and straw was higher under T3-100% RDF + 2 foliar spray of ZnSO4. Economics analysis viz gross return (123514), net return (84107) and benefit cost ratio (2.13) was recorded highest with T3-100% RDF + 2 foliar spray of ZnSO4 while lowest with T8- 100% RDF through FYM. Thus for obtaining better yield and profit apply T3-100% RDF + 2 foliar spray of ZnSO4.

Yield sustainability through micronutrient management in Guava

A field study conducted with soil and foliar application of ZnSO4 and borax at different phenological stages of guava cv. Shewta in sandy loam soil, revealed that highest sustainable yield index (0.80) was recorded with two sprays of 0.4% ZnSO4 + 0.2% borax during fruit growth at one month interval, followed by 0.63 with three sprays of 0.4% ZnSO4 + 0.2% borax before flowering, fruit set and during fruit growth. Highest TSS (13.13°Brix), acidity (0.652%) and ascorbic acid (262.21 mg/100 g) was recorded in two sprays of 0.4% ZnSO4 + 0.2% borax at fruit growth in one month interval. Significant differences in Zn and B content in guava fruit pulp was recorded. It was noted that Guava fruit pulp had Zn content of 13.7 mg kg-1 in control tree fruits while 14.6 to 16.5 mg kg-1 in treated trees. Moreover, guava fruit pulp enriched with B (14.3 to 17.3 mg kg-1) in treated tree fruits as compared to 12.4 mg kg-1 in control trees. Micronutrient contents in leaf tissues showed significant difference in Zn and B concentration, whereas, Fe, Mn and Cu contents were statistically non-significant. The index suggested for attaining the sustainability and to economize the nutrient application, technology package consisting of two sprays of 0.4% ZnSO4 and 0.2% borax during fruit growth at one month interval should be adopted at growers’ field.

Evaluación de parámetros hematológicos, estrés oxidativo, niveles de capacidad de unión de hierro y hierro insaturado en perros pastores Kangal, antes y después de la orquiectomía

Gonadectomy is a widely used method in reproductive health management, and behavior disorder therapies of domestic animals. Anemia and its development, one of the complications of surgical castration, which has been done so much recently in shelter dogs and dogs kept at home, has been investigated in male Kangal shepherd dogs. In castrated male Kangal shepherd dogs was to investigate the relationship between gonadectomy and oxidant and antioxidant levels, Iron (Fe) concentrations, unsaturated iron binding capacity (UIBC) and some blood parameters (RBC, HGB, HCT, MCV, RDW, MCHC). Blood samples were taken from 20 adult Kangal dogs brought to a clinic before castration (Day 0) and on the 1st, 3rd and 7th days. Some biochemical analyzes and blood parameters were evaluated in the blood samples taken. For this purpose, serum total oxidant–antioxidant capacity (TAC–TOC), Iron (Fe) concentrations, unsaturated iron binding capacity (UIBC) and some blood parameters (RBC, HGB, HCT, MCV, RDW, MCHC) were examined. In this study, it was evaluated the relationship between gonadectomy and oxidant–antioxidant capacity and Fe metabolism at some serum parameters in male dogs. After the orchidectomy operation, a remarkable decrease in clinical and statistical blood parameters was observed. As a result of this study, in the analysis of blood parameters, a severe picture of anemia was observed. It was determined an important role in erythropoiesis, with orchidectomy. The statistical difference in blood parameters (P<0.05) was indicative of this.

PM2.5-bound heavy metals in a typical industrial city of Changzhi in North China: Pollution sources and health risk assessment

Heavy metal contamination in fine particulate matter (PM2.5) emitted in industrial cities is extremely severe. Hence, determining their pollution sources apportionment is critical to inform effective pollution control strategies for reducing the risks associated with heavy metals in PM2.5. This study comprehensively investigated the characteristics, source apportionment, and health risks associated with heavy metals in PM2.5 at three monitoring stations—Jiance, Qinghua, and Shenjiju—in Changzhi, a typical industry city in China, during three seasons: autumn and winter of 2017 and summer of 2018. The daily average concentrations of PM2.5 (65.68 μg m−3) during the study period were lower than the second-grade limit value established in China (75 μg m−3). The highest mean PM2.5 concentrations were observed during winter (72.45 μg m−3) and at the Jiance station (64.51 μg m−3), respectively. At Qinghua station, vehicle emissions contributed more V to PM2.5, whereas Jiance station showed higher levels of Pb and Zn from coal combustion. In autumn, there was an increased in the Fe content in PM2.5 from vehicle emissions, whereas elevated concentrations of Cr and Ni from industry sources were observed in summer. According to the results of a positive matrix factorization, the main sources of PM2.5-bound heavy metals in Changzhi were coal combustion (34.3%), vehicle emissions (30.9%), fugitive dust (21.8%) and industry (13.0%). The major sources during autumn, winter, and summer were vehicle emissions (39.0%), coal combustion (35.0%), and industrial emissions (61.7%), respectively, showing a clear seasonal pattern. At both the Jiance station and Shenjiju station, extensive coal-based heating was the primary source of emissions, whereas vehicle emissions were the main source of emissions at QH owing to its high levels of traffic. The total hazard quotient (HQ) values for heavy metals were below the safe level (HQ = 1); but the carcinogenic risks (CR) exceed the lower limit of tolerance (1E-6). Stronger emissions from industrial sources in summer and the large amount of coal combustion for heating at the Jiance station are possible reasons for the higher health risk of heavy metals. Identification the source of PM2.5-bound heavy metals could support the targeted reduction of associated emissions, consequently helping alleviate heavy metals contamination and control associated risks to human health.

A Systematic Investigation of the Effects of Standard‐Sample Concentration Mismatch during Fe Isotope Measurement by MC‐ICP‐MS

Advances in multi‐collector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS) have led to the widespread use of iron (Fe) isotopes to elucidate the (bio)geochemical history of a range of environments. To generate Fe isotope ratio measurements, standard‐sample bracketing (SSB) is commonly used to correct for instrumental mass bias inherent to MC‐ICP‐MS. However, SSB is only accurate when sample and isotope standard Fe concentrations match, in addition to the bulk solution matrix. When the Fe concentrations differ, Fe isotope ratio measurement results may be inaccurate, a phenomenon known as the "self‐induced matrix effect." This study systematically characterised the self‐induced matrix effect for dry plasma Fe isotope ratio measurements on three MC‐ICP‐MS instruments and three introduction systems. Our extensive dataset indicates that: (1) the degree of mass bias is consistent regardless of MC‐ICP‐MS front‐end design, (2) the degree of mass bias becomes less reproducible as the concentration difference between the sample and bracketing standard increases, and (3) this applies to both pure Fe solutions and solutions from geological materials. This study reinforces the requirement to match bracketing standard and sample concentrations within 10% and provides a correction method for that fall beyond the recommended concentration range to subsequently allow for proper concentration matching during SSB.

Water Quality Assessment and Decolourisation of Contaminated Ex-Mining Lake Water Using Bioreactor Dye-Eating Fungus (BioDeF) System: A Real Case Study.

The environmental conditions of a lake are influenced by its type and various environmental forces such as water temperature, nutrients content, and longitude and latitude to which it is exposed. Due to population growth and development limits, former mining lakes are being converted to more lucrative land uses like those of recreational zones, agriculture, and livestock. The fungus Ganoderma lucidum has the potential to be utilised as a substitute or to perform synergistic bacteria-coupled functions in efficient contaminated lake water treatment. The purpose of this paper is to evaluate the water quality and water quality index (WQI) of an ex-mining lake named Main Lake in the Paya Indah Wetland, Selangor. Furthermore, the current work simulates the use of a Malaysian fungus in decolourising the contaminated ex-mining lake by the BioDeF system in a 300 mL jar inoculated with 10% (v/v) of pre-grown Ganoderma lucidum pellets for 48 h. According to the results, the lake water is low in pH (5.49 ± 0.1 on average), of a highly intense dark brownish colour (average reading of 874.67 ± 3.7 TCU), and high in iron (Fe) content (3.2422 ± 0.2533 mg/L). The water quality index of the lake was between 54.59 and 57.44, with an average value of 56.45; thus, the water was categorized as Class III, i.e., under-polluted water, according to the Malaysian Department of Environment Water Quality Index (DOE-WQI, DOE 2020). The batch bioreactor BioDeF system significantly reduced more than 90% of the water's colour. The utilization of Ganoderma lucidum as an adsorbent material offers a variety of advantages, as it is easily available and cultivated, and it is not toxic.

Effects of kitchen waste compost and chemical fertilizer application on spinach (Spinacia oleracea L.) c.v. Matador plant growth and nitrate accumulation

In this study, the effects of organic and chemical fertilizer sources on some essential nutrient elements content, nitrate (NO3 −-N) accumulation, and the growth of spinach plant (Spinacia oleracea L.) were investigated. The experiment was carried out in a randomized plot design under greenhouse conditions, with two levels. 1st level; applications with chemical fertilizer. 2nd level; applications without chemical fertilizer. One compost material (kitchen waste compost = KWC), five different doses (0, 0.4, 0.8, 1.2, and 1.6%), and three replications. For chemical fertilization, nitrogen (N) dose of 150 kg ha−1 was applied by using 15-15-15 NPK (N:P2O5:K2O) fertilizer. Overall, KWC applications increased plant growth and nutrient content. However, the most significant increases occurred in the trial subjects where chemical fertilizer and KWC were applied together. The use of KWC together with chemical fertilization increased the leaf width, leaf and stem length, fresh weight, and dry weight, as well as nitrate accumulation, N, potassium (K), and iron (Fe) content of the plant. The highest values of these parameters were obtained at 0.8% dose of KWC + NPK medium. As a result, compost applications were effectively uptake of nutrients and nitrate accumulation remained at acceptable values.

Influence of global warming and industrialization on coral reefs: A 600-year record of elemental changes in the Eastern Red Sea

The Red Sea has been recognized as a coral reef refugia, but it is vulnerable to warming and pollution. Here we investigated the spatial and temporal trends of 15 element concentrations in 9 coral reef sediment cores (aged from the 1460s to the 1980s AD) to study the influence of global warming and industrialization on the Eastern Red Sea coral reefs. We found Na, Ca, Cr, Fe, Co, Ni, and Sr concentrations were higher in the northern Red Sea (i.e., Yanbu), whereas Mg, P, S, Mn, and Cd concentrations were higher in the southern Red Sea (i.e., Thuwal & Al Lith) reef sediments. In the central (i.e., Thuwal) to southern (i.e., Al Lith) Red Sea, the study revealed diverse temporal trends in element concentrations. However, both reef sedimentation rates (−36.4 % and −80.5 %, respectively) and elemental accumulation rates (−49.4 % for Cd to −12.2 % for Zn in Thuwal, and −86.2 % for Co to −61.4 % for Cu in Al Lith) exhibited a declining pattern over time, possibly attributed to warming-induced thermal bleaching. In the central to northern Red Sea (i.e., Yanbu), the severity of thermal bleaching is low, while the reef sedimentation rates (187 %), element concentrations (6.7 % for S to 764 % for Co; except Na, Mg, Ca, Sr, and Cd), and all elemental accumulation rates (190 % for Mg to 2697 % for Co) exponentially increased from the 1970s, probably due the rapid industrialization in Yanbu. Our study also observed increased trace metal concentrations (e.g., Cu, Zn, and Ni) in the Thuwal and Al Lith coral reefs with severe bleaching histories, consistent with previous reports that trace metals might result in decreased resistance of corals to thermal stress under warming scenarios. Our study points to the urgent need to reduce the local discharge of trace metal pollutants to protect this biodiversity hotspot.

Experimental analysis on the effects of trace metals as micronutrients in enhancing biomethane production

Anaerobic digestion (AD) of microbial biomass has proven to be a significant breakthrough technique in producing biogas rich in methane. The quantity of biogas obtained by anaerobic digestion processes varies significantly based on the nature and characteristics of the substrates used. This research work focuses on the use of trace metals such as Fe, Cu, Zn, Mn, Mg, Ni in proper proportions to enhance the microbial consortium thus aiding in the production of biogas of desired quality. The substrate used for this study is Food Waste and Cow dung. Food waste from the college canteen was used as the substrate and cow dung was used as an inoculum for providing a catalytic effect in the anaerobic reactor. Food waste and cow dung in the ratio 75:25 was fed into the anaerobic digesters with varying concentrations of micronutrients supplemented to the reactors operating at a pH range maintained between 6.8 and 7.2 under room temperatures (22–27 ºC). The effect of these micronutrients on the anaerobic digestion process was observed by analysing the biogas yield, pH, alkalinity, total solids, and volatile solids of the samples. Sulphates of Fe, Cu, Mn, Ni and Chlorides of Zn and Mg was used in this study. Fe, Cu, Zn, Mn, Mg, Ni were fed to the anaerobic reactor at varying concentrations to arrive at the optimum dosage for the chosen substrates. The optimum dosage for the chosen substrate concentration was taken as that concentration which yielded maximum biogas yield with less retention time. Fe at concentrations varying from 1 mg/l–5 mg/l was fed to the anaerobic reactor and the optimum dosage for the chosen substrate concentration was noted at 1 mg/l. The reactor with an Fe concentration of 1 mg/l showed an increase in biogas production rate of about 68% compared to the sample without Fe supplementation as well as the ones with other dosages greater than 1 mg/l and less than 1 mg/l of Fe dosage. Each nutrient is subjected to an individual dosage analysis before arriving at the optimum dosage and then a mixture of the arrived optimum dosages will be analysed for further study. The process set-up will be conducted for a minimum retention period of 20 days and terminated when the results show a deep fall in the biogas production for consecutive days. Biogas produced for the nutrient supplementation of 1 mg/l of Fe, 0.5 mg/l of Cu, 1 mg/l of Zn, 0.5 mg/l of Mn, 1 mg/l of Mg and 0.5 mg/l of Ni yielded a biogas of 850 ml/g VS in 10 day retention time. Triplicate samples study were conducted and biogas yield measured daily to arrive at concordant results. The results showed an increase in the biomethane yields of the substrate by about 60% compared to the reactors which had no micronutrient supplementations. Furthermore, the study summarized that not all micronutrients are essential for a successful microbial metabolism to take place in an anaerobic digester as the micronutrient Manganese at varying dosages of 0.5 mg/l, 1 mg/l and 1.5 mg/l showed an antagonistic effect on the microbial activity in the reactor. The results obtained from this study showed a significant improvement in the quantity of biogas produced from the substrates supplemented with micronutrients at optimum dosages thus arriving at an efficient and effective method for treating waste in a sustainable way.

Effects of lime supply on the uptake of potassium and iron released from phlogopite by alfalfa

Understanding the influence of carbonates on nutrient release from minerals and their availability to plants is necessary for the management of calcareous soils. This study was conducted to investigate the effects of various levels of lime on the release of potassium (K) and iron (Fe) from the phlogopite mineral in the rhizosphere and their uptake by alfalfa. The experiment was conducted using a completely randomized design with a factorial arrangement. Alfalfa was grown in media containing a mixture of quartz sand, phlogopite, and different levels of lime (0, 20, 50, 120, and 250 g kg−1) under four types of nutrient solution (complete, Fe-free, K-free, and Fe and K free) with three replicates for six months. Alfalfa shoots and roots were harvested and their K and Fe concentrations were measured. The results showed that the biomass of both shoots and roots was significantly affected by lime. The presence of lime in the rhizosphere resulted in an increase in available Ca, thereby reducing the absorption of both K and Fe. The presence of lime was also found to change the K/Ca balance in the growth media. This appears to be the reason for the increased shoot K concentration in plants grown in the media containing less carbonates. It seems that at high concentrations in the soil solution, Ca competes greatly with Fe, reducing its availability to plants. In general, the rates of K and Fe release from phlogopite were adversely influenced by the level of carbonates in the root zone.

Adaptive Responses of Biofortified Common Bean Lines to Acidic Soil and High Temperatures in the Colombian Amazon Region

One of the strategies to combat micronutrient malnutrition is by developing biofortified common bean lines (Phaseolus vulgaris L.) capable of tolerating different stress conditions. In this study, the adaptive responses of different biofortified bean lines grown under combined stress of acidic soil and high-temperatures were evaluated in the Colombian Amazon. A total of 247 common bean lines from the Mesoamerican gene pool were used to determine the adaptive response in terms of phenological, physiological, and agronomic behavior under combined stress conditions. The lines tested were obtained from different single crosses, double crosses, and backcrosses between different bean materials, of which 146 were obtained from F4 families with high iron (Fe) content in seed and 99 common bean lines from F5 families. Different bean lines had grain yields (GY) higher than 1400 kg ha−1 from the F5 (lines: 859, 805, 865, and 657) and F4 (lines: 2853 and 2796) families. The superior performance of these lines was related to a higher photosynthate partitioning that has allowed an increase in pod formation (pod partitioning index, PPI) from the canopy biomass (CB) and grain filling (pod harvest index, PHI; harvest index, HI), resulting in higher values of GY. Values of GY were correlated with CB (r = 0.36), PPI (r = 0.6), PHI (r = 0.68), and HI (r = 0.8, p < 0.001). This increase in agronomic performance is due to a greater allocation of energy to the photosynthetic machinery (ΦII) and its dissipation in the form of heat (ΦNPQ), with increases in the leaf temperature difference (LTD). Based on the results obtained, six biofortified lines of common bean (lines F5: 859, 805, 865, and 657; lines F4: 2853 and 2796) showed traits of tolerance to combined stress and can serve as progenitors to increase Fe and Zn concentration in the seeds of lines that tolerate the combined stress from acidic soil and high temperature in the Colombian Amazon region.

The interplay between temporal and seasonal distribution of heavy metals and physiochemical properties in Kaap River

A key aspect of climate change is its impact on river water quality. Most research focuses on the impact of physiochemical parameters on water quality. However, the long-term shifts in temperatures and weather patterns coupled with anthropogenic activities play a significant role in river contamination. Metals are known to have toxic effects and environmental persistence. This study evaluated the heavy metal content of the Kaap River, where mining and agriculture are the primary land use. A 7-year study was conducted to investigate the seasonal relationship between heavy metals and physiochemical parameters (EC and pH). Fe, Al, As, and Mn concentrations were analysed in a laboratory accredited by the South African National Accreditation System (SANAS). The Python package Seaborn was used to generate heat maps for improved data visualization. Seasonal and temporal fluctuations had a combinatorial impact on Mn, Fe, and Al levels of the river. However, As levels were unaffected. The pH of the rivers was within the recommended range, despite flow regime, seasonal, and time-dependent fluctuations. Seasonal and temporal variations were also observed for EC, with the highest value of 42.35 mS/m being recorded during the winter of 2022, exceeding the recommended threshold of 30 mS/m. The correlation analysis revealed positive and significant correlations for the EC/pH and Al/Fe combinations and a weak degree of association for other parameters (P < 0.05). A permanent monitoring of water quality is required to ensure sustainable livelihoods and the safety of Kaap River water, which is subject to significant heavy metal fluctuations over time.

Application of Salicylic Acid Derivative in Modifying the Iron Nutritional Value of Lettuce (Lactuca sativa L.).

The present experiment addressed the effects of foliar sprays of different iron (Fe) concentrations (mg L-1), i.e., 2.8 (Fe I), 4.2 (Fe II), and 5.6 (Fe III), as well as an ionic derivative of salicylic acid (iSal) in two doses (10 and 20 mg L-1) on lettuce yield, chlorophyll and carotenoids content, and fluorescence parameters. Chemicals were used individually and in combinations two times, 23 and 30 days after the plants were transplanted. This experiment was carried out in a climate chamber. The Fe and iSal applications generally (except Fe I iSal, 10 mg L-1; Fe I iSal, 20 mg L-1; and Fe III iSal, 20 mg L-1) did not influence the fresh and dry matter content. The concentration of chlorophylls and carotenoids was reduced for all treatments in comparison to the control (without spraying). The Fe content in leaves was promoted in the Fe-treated plants (+70% for Fe III + iSal, 10 mg L-1, and Fe I). The iSal treatment promoted the Mn content. For most combinations, the Zn and Cu accumulations, as well as the fluorescence parameters, decreased after the foliar spray applications. Overall, our study revealed the effectiveness of Fe-DTPA chelate, but not iSal, in increasing the Fe content of lettuce grown in soilless cultivation systems.

Transcription factor MYB8 regulates iron deficiency stress response in Arabidopsis

Iron (Fe) is a crucial microelement for humans, animals, and plants. Insufficient Fe levels in plants impede growth and diminish photosynthesis, thus decreasing crop production. Notably, approximately one-third of the soil worldwide is alkaline and prone to Fe deficiency. Therefore, understanding the mechanisms underlying Fe absorption and transportation in plants can enhance Fe bioavailability in crops. In this study, the role of the transcription factor MYB8 in plant response to Fe deficiency in Arabidopsis was investigated via reverse genetics. Phenotype analysis revealed that the functional deletion mutant of MYB8 gene exhibited sensitivity to Fe deficiency stress, as indicated by shorter root length, lower chlorophyll content, and Fe concentration. Conversely, MYB8 overexpression strain showed a tolerant phenotype. Furthermore, qRT-PCR identified possible downstream MYB8-regulated genes. Moreover, MYB8 regulated the expression of iron-regulated transporter 1 (IRT1) by binding to the MYB binding sites motif (‘AACAAAC’) in its promoter.

Characteristics of particulate matter from asphalt pavement and tire of a moving bus through driving tests in city road and proving ground

Non-exhaust PM emissions from vehicles in real road have been conducted, but heavy vehicles have rarely been tested. In this study, PM2.5 and PM10 samples were directly collected from a tire of a moving bus and the composition was analyzed to investigate the sources of PM emissions. Driving tests were conducted at a proving ground (PG) and a city road (CR). PM2.5 emissions considerably increased when the lateral force of the tire increased and the vehicle accelerated. The PM emission rate was higher in the PG test than in the CR test because of the harsher driving conditions at PG. The emission rates of PM10 in the PG and CR tests were higher than those of PM2.5 by approximately 6 and 11 times, respectively. In the PG and CR tests, the proportions of tire wear particles (TWPs) were 4.9% and 2.1% in the PM2.5 samples, and 6.8% and 8.2% in the PM10 samples, respectively. Furthermore, TWPs with PM (TWPPM) were generated by other sources: secondary production of TWPPM by fragmentation of TWPs and resuspension of TWPPM on the road. The contributions of other sources to TWP2.5 generation were at least 6% and 57% in the PG and CR tests, respectively, whereas that to TWP10 generation was at least 3.5% in the CR test. Iron derived from brake abrasion and mineral particles was observed in the PM samples, and the Fe concentrations were higher in the PM10 samples than in the PM2.5 samples by over 9 and 18 times for the PG and CR tests, respectively. Sulfur sources, such as TWPs, exhaust gas, and bitumen, were observed in the PM samples. Based on our findings, we recommend that road wear particles should be removed from roads to reduce PM emissions upon driving.

Appraisal of trace metals toxicity and human health risk using a novel approach in wastewater of four gas fields, Bangladesh

The objective of this study is to assess the toxicity of trace metals (TMs) and associated environmental, ecological and health risks in the gas fields located in the Sylhet region of Bangladesh. Gas well-produced water, gas field discharge water, and drinking water surrounding the gas fields were collected for analysis. This study analyzed carcinogenic and noncarcinogenic TMs such as Cr, As, Co, Cd, Fe, Ni, Mn, Zn, and Pb, as well as physical parameters pH and EC in the collected samples using various instruments. The TMs were measured using Atomic Absorption Spectrometer (AAS), Flame AAS and physical parameters were evaluated using portable water multiparameter. The Fe and EC concentrations in produced and discharged water samples were incredibly high. The average concentrations of TMs in produced water samples during the summer and rainy seasons were found to be Fe > Mn > Zn > Ni > Co > Cu > Cr > Pb > As > Cd. The observed metal concentration in discharge water was higher during the summer than in the rainy season. Most samples met national and international standards for trace elements, while a few samples exceeded the threshold value.The Heavy Metal Evaluation Index (HMEI) results indicate that most produced water is highly polluted, while discharge and drinking water are moderate to lightly polluted. The Environmental Pollution Index (EPI) indicates environmental pollution for some produced water samples, while it indicates a moderate to low risk for discharge and drinking water samples. The source of trace metals (TMs) was determined using positive matrix factorization. However, all water samples have an ecological risk index of less than 150, indicating lower risk. Furthermore, the Heavy Metals Toxicity Load (HMTL) was below the allowable toxicity load for all water samples, indicating minimal contamination in the studied water. The non-cancer hazard score (HI) of the studied HMs is more significant for children and females than males. The cancer risk from Ni is a concern, while the cancer risk from Cd and Cr is also a matter of concern. In the end, policymakers can utilize this study's findings to monitor, and control produced water contamination.

The effects of different iron and phosphorus treatments on the formation and morphology of iron plaque in rice roots (Oryza sativa L).

Rice (Oryza sativa L.) is a pivotal cereal crop worldwide. It relies heavily on the presence of iron plaque on its root surfaces for optimal growth and enhanced stress resistance across diverse environmental conditions. To study the crystallographic aspects of iron plaque formation on rice roots, the concentrations of Fe2+ and PO4 3- were controlled in this study. The effects of these treatments were assessed through comprehensive analyzes encompassing root growth status, root surface iron concentration, root vitality, enzyme activities, and microstructural characteristics using advanced techniques such as root analysis, scanning electron microscopy (SEM), and ultrathin section transmission electron microscopy (TEM). The results demonstrated that an increase in the Fe2+ concentration or a decrease in the PO4 3- concentration in the nutrient solution led to improvements in various root growth indicators. There was an elevation in the DCB (dithionite-citrate-bicarbonate) iron content within the roots, enhanced root vitality, and a significant increase in the activities of the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) enzymes. Moreover, as the Fe2+ concentration increased, amorphous iron oxide minerals on the root surface were gradually transformed into ferrihydrite particles with sizes of approximately 200 nm and goethite particles with sizes of approximately 5 μm. This study showed that an increase in the Fe2+ concentration and a decrease in the PO4 3- concentration led to the formation of substantial iron plaque on the root surfaces. It is noteworthy that there was a distinct gap ranging from 0.5 to 3 μm between the iron plaque formed through PO4 3- treatment and the cellular layer of the root surface. This study elucidated the impacts of Fe2+ and PO4 3- treatments on the formation, structure, and morphology of the iron plaque while discerning variations in the spatial proximity between the iron plaque and root surface under different treatment conditions.

Response of Cadmium in Soil-rice to Different Conditioners Based on Field Trials

A plot experiment was carried out to assess the applicability of soil conditioners on Cd-polluted acidic paddy fields. The effects of five soil conditioners[Tianxiang 1 Hao (TX1), limestone (Li), silicon fertilizer, Nuodikang (NDK), and calcium magnesium phosphate fertilizer (CaMg-P)] on Cd accumulation and transport between contaminated soil and rice plants and rice yield on the land were analyzed. The results showed that compared with that under the control, other tested methods increased soil pH by 0.41-0.68 units and decreased available Cd content in the soil by 11.2%-39.7%. The difference between Li- and NDK-treated soil available Cd reached a significant level (P &lt; 0.05). ② Compared with that in the blank control, the application of soil conditioner could significantly reduce the total amount of Cd in rice, and the Cd content in roots, other leaves, rachises, chaffs, and brown rice were significantly lower than those in the CK treatment (P &lt; 0.05). The Cd translation factor between various sites was shown as TFroots-other nodes &gt; TFroots-first nodes &gt; TFroots-rachises &gt; TFroots-chaffs ≈ TFroots-flag leaves &gt; TFroots-brown rice. The Cd content of brown rice met the national safety standard (0.2 mg·kg-1), in which the TX1, Li, and CaMg-P treatments showed significant Cd reduction effects, and ω(Cd) was 0.097, 0.094, and 0.134 mg·kg-1, respectively. ③ The application of soil conditioner could increase the yield by 9.9%-35.8%, and the yield of the CaMg-P and TX1 treatments was significantly higher than that of other treatments (P &lt; 0.05). ④ Correlation analysis showed that the Cd content in brown rice was significantly positively correlated with available Cd content in soil, available Fe content in soil, and available phosphorus but negatively correlated with soil pH. In summary, TX1 and CaMg-P are recommended to be applied in farmland lightly polluted by the heavy metal Cd to ensure the safety of agricultural products.

A Low-Cost, Tabletop LOD-EPR System for Nondestructive Quantification of Iron Oxide Nanoparticles in Tissues.

Iron oxide nanoparticles (IONPs) have wide utility in applications from drug delivery to the rewarming of cryopreserved tissues. Due to the complex behavior of IONPs (e.g., uneven particle distribution and aggregation), further developments and clinical translation can be accelerated by having access to a noninvasive method for tissue IONP quantification. Currently, there is no low-cost method to nondestructively track IONPs in tissues across a wide range of concentrations. This work describes the performance of a low-cost, tabletop, longitudinally detected electron paramagnetic resonance (LOD-EPR) system to address this issue in the field of cryopreservation, which utilizes IONPs for rewarming of rat kidneys. A low-cost LOD-EPR system is realized via simultaneous transmit and receive using MHz continuous-wave transverse excitation with kHz modulation, which is longitudinally detected at the modulation frequency to provide both geometric and frequency isolation. The accuracy of LOD-EPR for IONP quantification is compared with NMR relaxometry. Solution measurements show excellent linearity (R2 > 0.99) versus Fe concentration for both measurements on EMG308 (a commercial nanoparticle), silica-coated EMG308, and PEG-coated EMG308 in water. The LOD-EPR signal intensity and NMR longitudinal relaxation rate constant (R1) of water are affected by particle coating, solution viscosity, and particle aggregation. R1 remains linear but with a reduced slope when in cryoprotective agent (CPA) solution, whereas the LOD-EPR signal is relatively insensitive to this. R1 does not correlate well with Fe concentration in rat kidney sections (R2 = 0.3487), while LOD-EPR does (R2 = 0.8276), with a linear regression closely matching that observed in solution and CPA.