Pb Levels Research Articles

Impact of natural events on metal bioaccumulation in Anemonia sulcata

Samples of Anemonia sulcata were collected in 2022 from different areas of the Canary Islands affected by different natural contamination sources, such sandstorms, submarine volcanic activity, continuous rainfall, upwelling and dinoflagellate blooms. Significant differences were observed between the zones for the metals and trace elements analyzed (Al, Zn, Cd, Pb, Ni, Co, Fe, B, Cu, Mg and Li). Anemones from volcanic areas showed higher levels of Cd, Pb and Ni. Individuals from sandstorm areas showed elevated levels of Al, Zn and Fe. Samples collected from areas affected by upwelling processes had higher concentrations of Cu, Mg and Li. Finally, the areas affected by dinoflagellates showed lower levels of Zn, Pb, Fe, Mg and Li. The study reveals how natural phenomena dramatically influence metal accumulation in A. sulcata, which is of great value for anticipating and managing potential problems associated with public health.

Physio-biochemical Behavior and Health Effects of Pepper Plants Subjected to Lead Stress and Their Responses to Remediating Agents as Microbial Activity and Phosphorus

This work assessed the alleviating effects of bacteria (Bacillus subtilis) and phosphorus as environmentally friendly materials on the cultivation of pepper plants in polluted soil with lead (Pb) in forms of PbSO4, and Pb(NO3)2 at rates of 0, 1000, 2000 and 3000 µg Pb/g soil. Pot experiments were conducted to study the growth parameters, some physiological factors, biochemical constituents, and yield attributes, as well as the tolerance index (TI), translocation factor (TF), bioconcentration factor (BCF), and health effects [daily intake of heavy metals (DIM), health risk index (HRI), and carcinogenic risk (CR)]. Increasing the Pb concentration of all Pb salt used in soil severely affected the plant vegetative growth parameters. In comparison with other Pb salt forms, Pb(NO3)2 salt had a strong inhibitory impact. Additionally, the photosynthetic pigments in leaves were negatively impacted by all Pb salt forms. The application of Pb in all salt forms led to changes in the leaf water deficit (LWD), osmotic pressure, and membrane integrity and decreased the total water content, relative water content (RWC), transpiration rate, and leaf succulence. Pollution with Pb salts considerably decreased the yield constituents and various chemical properties of pepper, more so in the presence of Pb nitrate than in the presence of Pb sulfate type. A comparison of the concentration of Pb presence of Pb nitrate was greatly increased than the Pb sulfate in the whole plants. The safe limit of 0.3 mg/kg was exceeded by the Pb concentration in pepper fruits (6.3 and 4.3 mg/kg) cultivated in Pb-contaminated soil [with Pb(NO3)2 and PbSO4, respectively]. Additionally, Pb sulfate had a greater detrimental effect on Pb uptake in several plant organs than other Pb salt forms. The TI of pepper plants treated with salt types was >60% with PbSO4 (75.6%), whereas it was <60% with Pb(NO3)2 (35.2%). The BCF values of pepper plants in the polluted Pb soils varied from 0.10 to 0.41, indicating a moderate accumulator plant. At every level of Pb contamination with all Pb salt types, the sequence of Pb TF values was as follows: roots (TFr) > shoots (TFsh) > fruits (TFf), with TF values < 1. When compared with TFr and TFsh, TFs for shoot to fruits (TFf) had the lowest values (range, 0.07–0.22). The DIM, HRI, and CR values of pepper plants revealed that the Pb of fruit of stressed pepper plants is within safe limits. In addition to reducing the detrimental effects of intolerable Pb levels (2000 and 3000 µg Pb/g soil) on the majority of the aforementioned characters, adding Bacillus bacteria as a bio-agent and phosphorus as a chemo-agent to Pb-polluted soils also stimulated growth, increased yield, controlled plant water relations, protected photosynthetic pigments, and sharply decreased the Pb accumulation in plant organs. The Bacillus bacteria application resulted in some superior characteristics, such as root length, leaf number, leaf length, leaf area, leaf area index, fresh biomass, dry biomass, photosynthetic pigments, quantity yield attributes, reduction Pb accumulation in all plant organs, TI, TFr, TFf, BCF, in health effects trials, whereas phosphorus application improved plant height, leaf width, RWC, LWD, osmotic pressure, total soluble solids, acidity, total carbohydrates, total protein, and TFsh.

Health risk assessment of heavy metal pollutants in Iranian hen eggs: a systematic review and meta-analysis.

Eggs are a high-quality, nutrient-dense source of protein that is available at a relatively low price and the contamination of eggs by heavy metals is an important issue in public health. This review aimed to assess the risk of heavy metal pollutants in Iranian hen eggs. Original full-text available studies in Iran, detecting levels of Pb, Cd, As, and Hg in whole or part of the egg, and published between January 2000 and March 2023 were selected based on the inclusion criteria. The random-effect model was used to estimate the pooled concentrations of Pb, Cd, As, and Hg in Iranian eggs in meta-analysis. The incremental lifetime cancer risk (ILCR) and the target hazard quotient (THQ) were estimated by both calculation and Monte Carlo simulations to determine the carcinogenic and non-carcinogenic risk of egg consumption, respectively. The pooled concentrations of heavy metals in Iranian hen eggs from nine articles (11 datasets: 10 studies on Pb, 7 on Cd, and 5 on As and Hg concentrations) were Pb 0.29 (95% CI 0.20-0.39) mg kg-1, Cd 0.04 (95% CI 0.03-0.06) mg kg-1, As 0.05 (95% CI 0.03-0.07) mg kg-1, and Hg 0.03 (95% CI 0.02-0.04) mg kg-1. THQ did not show the non-carcinogenic risk; however, the ILCR for Pb concentration showed the threshold carcinogenic risk (mean ILCR = 8.94e - 4 and 9.0E - 4 by calculation and Monte Carlo simulations, respectively), with the greater risk for Cd (mean ILCR = 2.02e - 2). The carcinogenic risk of Pb and Cd concentration in Iranian hen eggs shows the urgent need for programs and policies to lower the risk for consumers by providing healthier feeding.

Evaluation of soil pollution by heavy metal using index calculations and multivariate statistical analysis.

This study aims to assess the extent of heavy metals (HMs) pollution in soil and identify its potential sources using single and integrated pollution index calculations, and multivariate statistical analysis. The HM concentrations of soil samples were analyzed using ICP-MS. The concentrations (mg/kg) of arsenic (As) ranged from 2.8 to 208.1, cadmium (Cd) from 0.1 to 0.3, cobalt (Co) from 1.9 to 20.5, copper (Cu) from 3.7 to 17.7, nickel (Ni) from 14.7 to 110.6, and lead (Pb) from 6.7 to 37.3. High levels of As contents and physicochemical parameters were found in the northeastern parts of the study area, while levels of other HMs were high in the remaining parts. The HM contents of some soil samples exceeded the average values of basalt and limestone in the study area, as well as the upper, bulk, and lower continental crusts, shale, and soil (worldwide). Multiple index methods were used to assess the pollution risk, and it was determined that some soil samples were moderately to considerably contaminated with varying levels of As, Cd, Co, Ni, and Pb. Multivariate statistical analyses provided that the source of HMs contamination in the soil was a result of geogenic and/or anthropogenic activities. Geogenic sources were associated with weathering rock units, while anthropogenic sources were linked to industrial activities, traffic emissions, and agricultural applications. The findings are useful for detecting contamination by HMs in soil, and they could contribute to future monitoring programs to prevent soil contamination and protect the health of living organisms.

Heavy Metal Accumulation in Three Varieties of Mustard Grown under Five Soil Management Practices

Heavy metal pollution represents a global health issue. Different methods and technologies are adopted to mitigate the problem of heavy metal pollution. Phytoremediation has been gaining attention as an environmentally friendly method to remediate this problem. The purpose of this research is to explore the effectiveness of phytoremediation in agricultural settings to assess the effect of five soil management practices (chicken manure, sewage sludge, leaf compost, cow manure, and vermicompost) on Cd, Cu, Mo, Ni, Pb, and Zn accumulation in the mustard (leaves and pods) of three mustard Brassica juncea varieties (black mustard, yellow mustard, and mighty mustard). The accumulation in mustard was quantified using the Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). The results showed that the bioaccumulation factor (BAF) of the three mustard varieties exceeded one (BAF > 1) for Cd and Mo. It indicates that mustard is a good accumulator of Cd and Mo, whereas BAF values for Cu, Pb, Ni, and Zn were less than one (BAF < 1). The accumulated Cu, Mo, Ni, and Zn levels were below the allowable limit, whereas the Cd and Pb levels were beyond the limit. This result indicates that the investigated mustard varieties can be grown on heavy metal polluted sites for Cd and Mo phytoremediation purposes, but care is needed with regard to Cd and Mo toxicity.

Mosses as bioindicators of air pollution with potentially toxic elements in the Burabay State National Natural Park, Kazakhstan.

The Burabay State National Natural Park is a national park of the great natural and historical values located in the north of Kazakhstan, which has been exposed in recent years to significant anthropogenic impact. The moss biomonitoring was performed in the Borovoye resort community, an important tourist destination in the national park, to identify the level of air pollution. Mosses collected at 29 locations were subjected to neutron activation analysis to determine 36 elements and additionally to ICP-OES to detect the level of Cu and Pb. Factor analysis was applied to check if there are any associations between identified elements and to link them with possible emission sources. According to contamination factor and pollution load indices the investigated area belongs to three classes of pollution: unpolluted, suspected and moderate. Potential ecological risk index calculated for selected elements revealed harmless risk to human health. The level of element obtained in Burabay State National Natural Park was compared with the data available for other national parks.

Integrated assessment of potentially toxic elements in soil of the Kangdian metallogenic province: A two-point machine learning approach

The accumulation of potentially toxic elements in soil poses significant risks to ecosystems and human well-being due to their inherent toxicity, widespread presence, and persistence. The Kangdian metallogenic province, famous for its iron-copper deposits, faces soil pollution challenges due to various potentially toxic elements. This study explored a comprehensive approach that combinescombines the spatial prediction by the two-point machine learning method and ecological-health risk assessment to quantitatively assess the comprehensive potential ecological risk index (PERI), the total hazard index (THI) and the total carcinogenic risk (TCR). The proportions of copper (Cu), cadmium (Cd), manganese (Mn), lead (Pb), zinc (Zn), and arsenic (As) concentrations exceeding the risk screening values (RSVs) were 15.03%, 5.1%, 3.72%, 1.24%, 1.1%, and 0.13%, respectively, across the 725 collected samples. Spatial prediction revealed elevated levels of As, Cd, Cu, Pb, Zn, mercury (Hg), and Mn near the mining sites. Potentially toxic elements exert a slight impact on soil, some regions exhibit moderate to significant ecological risk, particularly in the southwest. Children face higher non-carcinogenic and carcinogenic health risks compared to adults. Mercury poses the highest ecological risk, while chromium (Cr) poses the greatest health hazard for all populations. Oral ingestion represents the highest non-oncogenic and oncogenic risks in all age groups. Adults faced acceptable non-carcinogenic risks. Children in the southwest region confront higher health risks, both non-carcinogenic and carcinogenic, from mining activities. Urgent measures are vital to mitigate Hg and Cr contamination while promoting handwashing practices is essential to minimize health risks.

Ecological risk assessment of heavy metals in desulfurized seawater discharged from a coal-fired power plant in Qingdao.

Despite the prevalence of discharge of large volumes of heavy-metal-bearing seawater from coal-fired power plants into adjacent seas, studies on the associated ecological risks remain limited. This study continuously monitored concentrations of seven heavy metals (i.e. As, Cd, Cr, Cu, Hg, Pb, and Zn) in surface seawater near the outfall of a coal-fired power plant in Qingdao, China over three years. The results showed average concentrations of As, Cd, Cr, Cu, Hg, Pb, and Zn of 2.63, 0.33, 2.97, 4.63, 0.008, 0.85, and 25.00 μg/L, respectively. Given the lack of data on metal toxicity to local species, this study investigated species composition and biomass near discharge outfalls and constructed species sensitivity distribution (SSD) curves with biological flora characteristics. Hazardous concentrations for 5% of species (HC5) for As, Cd, Cr, Cu, Hg, Pb, and Zn derived from SSDs constructed from chronic toxicity data for native species were 3.23, 2.22, 0.06, 2.83, 0.66, 4.70, and 11.07 μg/L, respectively. This study further assessed ecological risk of heavy metals by applying the Hazard Quotient (HQ) and Joint Probability Curve (JPC) based on long-term heavy metal exposure data and chronic toxicity data for local species. The results revealed acceptable levels of ecological risk for As, Cd, Hg, and Pb, but unacceptable levels for Cr, Cu, and Zn. The order of studied heavy metals in terms of ecological risk was Cr > Cu ≈ Zn > As > Cd ≈ Pb > Hg. The results of this study can guide the assessment of ecological risk at heavy metal contaminated sites characterized by relatively low heavy metal concentrations and high discharge volumes, such as receiving waters of coal-fired power plant effluents.

Heavy metal association with chronic kidney disease of unknown cause in central India-results from a case-control study

BackgroundChronic Kidney Disease of unknown cause (CKDu) a disease of exclusion, and remains unexplained in various parts of the world, including India. Previous studies have reported mixed findings about the role of heavy metals or agrochemicals in CKDu. These studies compared CKDu with healthy controls but lacked subjects with CKD as controls. The purpose of this study was to test the hypothesis whether heavy metals, i.e. Arsenic (As), Cadmium (Cd), Lead (Pb), and Chromium (Cr) are associated with CKDu, in central India.MethodsThe study was conducted in a case-control manner at a tertiary care hospital. CKDu cases (n = 60) were compared with CKD (n = 62) and healthy subjects (n = 54). Blood and urine levels of As, Cd, Pb, and Cr were measured by Inductively Coupled Plasma- Optical Emission Spectrometry. Pesticide use, painkillers, smoking, and alcohol addiction were also evaluated. The median blood and urine metal levels were compared among the groups by the Kruskal-Wallis rank sum test.ResultsCKDu had significantly higher pesticide and surface water usage as a source of drinking water. Blood As levels (median, IQR) were significantly higher in CKDu 91.97 (1.3–132.7) µg/L compared to CKD 4.5 (0.0–58.8) µg/L and healthy subjects 39.01 (4.8–67.4) µg/L (p < 0.001) On multinominal regression age and sex adjusted blood As was independently associated with CKDu[ OR 1.013 (95%CI 1.003–1.024) P < .05].Blood and urinary Cd, Pb, and Cr were higher in CKD compared to CKDu (p > .05). Urinary Cd, Pb and Cr were undetectable in healthy subjects and were significantly higher in CKDu and CKD compared to healthy subjects (P = < 0.001). There was a significant correlation of Cd, Pb and Cr in blood and urine with each other in CKDu and CKD subjects as compared to healthy subjects. Surface water use also associated with CKDu [OR 3.178 (95%CI 1.029–9.818) p < .05).ConclusionThe study showed an independent association of age and sex adjusted blood As with CKDu in this Indian cohort. Subjects with renal dysfunction (CKDu and CKD) were found to have significantly higher metal burden of Pb, Cd, As, and Cr as compared to healthy controls. CKDu subjects had significantly higher pesticide and surface water usage, which may be the source of differential As exposure in these subjects.

Blood Concentration of Macro- and Microelements in Women Who Are Overweight/Obesity and Their Associations with Serum Biochemistry

Risk elements in blood matrices can affect human health status through associations with biomarkers at multiple levels. The aim of this study was to analyze 15 macro- and microelements in the blood serum of women with overweight (BMI of ≥25 kg/m2) and obesity (BMI of ≥30 kg/m2) and to examine possible associations with biochemical, liver enzymatic parameters, and markers of oxidative stress. Based on the power calculation, the study involved women (in the postmenopausal stage) whom are overweight (n = 26) and obese (n = 22), aged between 50–65 years. Multifrequency bioelectrical impedance analysis was used to measure body composition parameters. Concentrations of elements were determined by inductively coupled plasma optical emission spectrometry, and Hg was measured using cold-vapor atomic absorption spectroscopy. Individuals with obesity, as indicated by a higher BMI, percentage of body fat, and visceral fat area, had elevated serum levels of Ca, Mg, Fe, Al, Sr, Pb, and Hg. Concentrations of Al, Cu, K, Sb, Zn, and Pb significantly affected biochemical and liver function markers in women who were overweight or obese. Elements such as Cu and Al were associated with increased total cholesterol. The correlation analysis between total antioxidant status and Cu, Al, and Ni confirmed associations in both groups. Our findings underscore the importance of addressing excess body weight and obesity in relation to risk elements. The results of the research could be beneficial in identifying potential targets for the treatment or prevention of comorbidities in people with obesity.

Errors in agricultural practices increase the toxicity of heavy metals in the food chain at Ishwardi Upazila in Bangladesh

Due to the potential harm to human health, heavy metal deposition in agricultural products has.gained importance throughout the world. Excessive use of agrochemicals and poultry wastes dramatically increased during the cultivation processes of rapidly growing vegetables without maintaining authorized guidelines. happens due to the availability and low cost of these materials and higher production of the vegetables. Higher levels of heavy metals, especially Arsenic (As), Lead (Pb), Chromium (Cr), and Cadmium (Cd) contamination in food have detrimental effects on human health as well as the environmental ecosystems. This study revealed the profile of the heavy metals in the fast-growing vegetable called red amaranth (Amaranthus cruentus) due to the frequent use of poultry manure. We collected a total of 75 samples of red amaranth, water, and soil from five villages of five different unions at Ishwardi upazila in Bangladesh, and we analyzed the contamination levels of As, Pb, Cr, and Cd in them. Except for the As, we found that the accumulation levels of Pb, Cr, and Cd in samples crossed the highest permissive limit compared to FAO/WHO standards. Results suggested that daily intake of red amaranth in this area is alarming to human health due to the detrimental effects of these heavy metals.

Early-Life Lead Exposure: Risks and Neurotoxic Consequences.

Lead (Pb) does not have any biological function in a human, and there is likely no safe level of Pb in the human body. The Pb exposure impacts are a global concern for their potential neurotoxic consequences. Despite decreasing both the environmental Pb levels and the average blood Pb levels in the survey populations, the lifetime redistribution from the tissues-stored Pb still poses neurotoxic risks from the low-level exposure in later life. The growing fetus and children hold their innate high-susceptible to these Pb-induced neurodevelopmental and neurobehavioral effects. This article aims to evaluate the cumulative studies and insights on the topic of Pb neurotoxicology while assessing the emerging trends in the field. The Pb-induced neurochemical and neuro-immunological mechanisms are likely responsible for the high-level Pb exposure with the neurodevelopmental and neurobehavioral impacts at the initial stages. Early-life Pb exposure can still produce neurodegenerative consequences in later life due to the altered epigenetic imprints and the ongoing endogenous Pb exposure. Several mechanisms contribute to the Pb-induced neurotoxic impacts, including the direct neurochemical effects, the induction of oxidative stress and inflammation through immunologic activations, and epigenetic alterations. Furthermore, the individual nutritional status, such as macro-, micro-, or antioxidant nutrients, can significantly influence the neurotoxic impacts even at low-level exposure to Pb. The prevention of early-life Pb exposure is, therefore, the critical determinant for alleviating various Pb-induced neurotoxic impacts across the different age groups.

Comprehensive Assessment of Heavy Metal Pollution and Ecological Risk in Lakes of Bangalore, Karnataka, India

The contamination of water and sediment by heavy metals poses significant challenges to freshwater ecosystems, agriculture, and aquaculture. This study focused on assessing heavy metal pollution in Ulsoor and Agara Lakes, prominent freshwater reservoirs in Bengaluru utilized for aquaculture. The presence of heavy metals such as Cd, Cu, Zn, Cr and Pb levels were analyzed in water and sediment samples of both lakes over a period of one year (from August 2021 to July 2022), using an Atomic Absorption Spectrometer. Pollution indices (CF, Igeo, PLI, ERI) were computed for sediment, revealing higher metal concentrations compared to water. Correlation analysis identified strong associations between Zn and Cu, Pb and Zn in water, and Cu and Cd in sediment, suggesting common pollution sources. While sediment showed relative safety based on PLI, Igeo, and ERI, CF indicated an unpolluted to moderately polluted status. In conclusion, this study revealed that most metals in the water exceeded permissible limits, highlighting the need for effective remediation measures.

A case-control study on asthma and obese patients: Influence of lifestyle patterns, serum trace elements, heavy metals, and total antioxidants

Background and aimAsthma is a chronic airway hyperresponsiveness disorder and Obese people have greater rates of asthma incidence and prevalence. Obesity, a complex condition, can cause nutritional metabolic problems that change trace elements and minerals. Trace element and antioxidant levels affect asthma aetiology. In this study, we aim to determine the serum levels of trace elements Zn, Fe, Cu, Mg, Co, Ni, Pb, Cd, and Cr, total antioxidants (TAS), and lifestyle that determine specific clinical conditions in asthma and obesity patients from Vellore City (Tamil Nadu, India). MethodsA case-control study to determine the level of the serum trace elements with 838 subjects (n = 242 asthma patients, n = 140 asthmatic obese, n = 185 obese patients, and n = 271 controls) between the ages of 20 and 60 years was carried out. Asthma was diagnosed based on the clinical examination and pulmonary function tests. Trace element levels were determined by atomic absorption spectrophotometry (AAS) in serum, and a DPPH-free radical scavenging assay was used to determine the total antioxidant capacity level in serum. ResultIn asthma male patients, serum levels of Zn, Fe, Cu, Mg, and TAS were significantly lower and Pb, Cd, and Cr significantly higher, whereas in female asthma patients, serum levels of Zn, Fe, Mg, and TAS were significantly lower and Pb significantly higher. In asthmatic obese male patients, Fe, Cu, and TAS were significantly lower, and Pb, Cd, and Co were significantly higher; in asthmatic obese female patients, Zn, Fe, Cu, Mg, and TAS were significantly lower, and Ni was significantly higher. In obese male patients, Zn, Fe, Cu, and TAS were significantly lower and Cd was significantly higher, and in obese female patients, Zn, Fe, Cu, Mg, and TAS were significantly lower. ConclusionThe influence of the level of trace elements, heavy metal, total antioxidant, and the lifestyle patterns, may increase the risk of asthma and obesity.

Insights into growth stages and genotypes in airborne Pb accumulation in Oryza sativa L. grains: Utilizing isotope fingerprinting alongside a model study

Atmospheric exposure is an important pathway of accumulation of lead (Pb) in Oryza sativa L. grains. In this study, source contributions of soil, early atmospheric exposure, and late atmospheric exposure, along with their bioaccumulation ratios were examined both in the pot and field experiments using stable Pb isotope fingerprinting technology combined with a three-compartment accumulation model. Furthermore, genotype differences in airborne Pb accumulation among four field-grown rice cultivars were investigated using the partial least squares path model (PLS-PM) linking rice Pb accumulation to agronomic traits. The findings revealed that during the late growth period, the air-foliar-grain transfer of Pb was crucial for rice Pb accumulation. Approximately 69–82% of the Pb found in polished rice was contributed by atmospheric source, with more than 80% accumulating during the late growth stage. The air accumulation ratios of rice grains were genotype-specific and estimated to be 0.364–1.062 m3/g during the late growth. Notably, grain size exhibited the highest standardized total effects on the airborne Pb concentrations in the polished rice, followed by leaf Pb and the upward translocation efficiency of Pb. The present study indicates that mitigating the health risks associated with Pb in rice can be achieved by controlling atmospheric Pb levels during the late growth stage and choosing Japonica inbred varieties characterized by large grain size.

The Determination and evaluation of trace elements in the blood of radiography workers using graphite furnace atomic absorption spectrometry

This study aimed to evaluate the potentially toxic effects of trace elements in the blood of Iraqi medical radiography workers by analyzing them through GF-AAS. The study involved 50 male blood radiography workers from the medical imaging field at Al-Shatrah General Hospital in Thi-Qar City, Iraq. All workers were aged between 35-50 years and had worked for less than 10 years. The study compared these workers with 50 healthy men. The study found a significant increase in the levels of Cu, Pb, Cd, and Ca among radiography workers compared to the healthy control group, while Zn and Se levels decreased significantly. Moreover, Specificity and confidence interval (95%) were estimated via the receiver operating characteristic curve (ROC). The study provided conclusive evidence of disturbances in the levels of trace elements in the blood of radiographer workers, which makes them more susceptible to many diseases because of their radiation exposure. which portends the more preventive measures of radiation. The linear range of Cd, Cu, Zn, Se and Pb in human serum were obtained 0.2-6.0 µg dL-1, 6.0-200 µg dL-1, 8.0-200 µg dL-1, 10-250 µg dL-1, 4-120 µg dL-1 by GF-AAS after dilution samples with DW up to 20 (n=10, RSD&lt; 5%).

Optimising coagulation/flocculation using response surface methodology and application of floc in biofertilisation

Abstract Aquaculture effluent generation, an environmentally crucial process requires effective treatment. Simple methods like coagulation and flocculation are considered effective. In this study, chitosan from Black tiger shrimp, Penaeus monodon, was used to remove ammonia (NH3) and turbidity. Response surface methodology-optimised dosages (5.00, 12.50, and 20.00 mg·L−1), pH (5.00, 6.25, and 7.50), and settling times (5.00, 7.50, and 30.00 min) were applied. Water spinach, Ipomea aquatica, received an application for organic fertiliser after the nutrient status of the recovered floc was later determined. Results showed that at a dose of 16.25 mg·L−1, a pH of 7.5, and a settling time of 17.5 min, chitosan cleared 92.16% of the turbidity. After 30 min of settling, 84.42% of the NH3 was eliminated at 5 mg·L−1 and 7.5 pH. Both macronutrients (P, K, N, Mg, and Ca) and micronutrients (Co, Cu, Fe, Mn, Ni, Se, and Zn) are present in the newly discovered floc. Floc had safe low Pb and Ni levels. Plants treated with floc showed superior growth compared to those with commercial liquid fertiliser, confirming nutrient absorbability. Conclusively, this study provides an eco-friendly wastewater treatment method.

Exploring the combined effect of heavy metals on accumulation efficiency of Salix alba raised on lead and cadmium contaminated soils

The present study illustrated that Salix alba can accumulate high level of Pb and Cd in different plant parts, with maximum accumulation in roots followed by stem and leaves in the order Cd > Pb > Cd + Pb. The phytoremediation evaluation factors such as bioconcentration factor (BCF) and translocation factor (TF) was higher for Cd over Pb in all plant parts, further the BCF for both Pb and Cd was maximum in root (BCF > 1) followed by stem and leaves. Higher accumulation of Cd over the Pb was observed inside the plant tissues due to Cd mimics with other elements and gets transported through respective transporters. The combined treatment of Pb and Cd affected the bioaccumulation at every treatment level suggesting the negative effect among both elements. Higher survival rate (>85%) was recorded up to 200mgPb/kg and 15mgCd/kg, while further increase in metal concentration reduced the plant efficiency to remediate contaminated soils, hence results in declined survival rate. The FTIR analysis revealed that Pb and Cd accumulation in plants induced changes in carboxy, amino, hydroxyl and phosphate groups that ultimately caused alteration in physiological and biochemical processes of plant and thus provided an insight to the interaction, binding and accumulation of heavy metals.

Blood lead levels in an endangered vulture decline following changes in hunting activity

Lead ammunition stands out as one of the most pervasive pollutants affecting wildlife. Its impact on bird populations have spurred efforts for the phase-out of leaded gunshot in several countries, although with varying scopes and applications. Ongoing and future policy changes require data to assess the effectiveness of adopted measures, particularly in the current context of biodiversity loss. Here, we assessed the long-term changes in blood lead (Pb) levels of Egyptian vultures from the Canary Islands, Spain, which have been severely affected by Pb poisoning over the past two decades. During this period, the reduction in hunting pressure and changes in legislation regarding firearms usage for small game hunting likely contributed to a decrease in environmental Pb availability. As anticipated, our results show a reduction in Pb levels, especially after the ban on wild rabbit hunting with shotgun since 2010. This effect was stronger in the preadult fraction of the vulture population. However, we still observed elevated blood Pb levels above the background and clinical thresholds in 5.6% and 1.5% of individuals, respectively. Our results highlight the positive impact of reducing the availability of Pb from ammunition sources on individual health. Nonetheless, the continued use of Pb gunshot remains an important source of poisoning, even lethal, mainly affecting adult individuals. This poses a particular concern for long-lived birds, compounding by potential chronic effects associated with Pb bioaccumulation. Our findings align with recent studies indicating insufficient reductions in Pb levels among European birds of prey, attributed to limited policy changes and their uneven implementation. We anticipated further reductions in Pb levels among Egyptian vultures with expanded restrictions on hunting practices, including a blanket ban on Pb shot usage across all small game species.

Growth and Phytochemistry of Cymbopogon citratus Stapf Inoculated with Plant Growth-Promoting Bacteria under Different Lead Levels.

This study aimed to investigate the phytochemistry of lemongrass (Cymbopogon citratus) inoculated with Azospirillum brasilense and grown in lead (Pb)-contaminated soil to assess its responses to inoculation under different Pb levels. The experimental design was completely randomized in a 2 × 5 factorial scheme: two levels of A. brasilense (absence or presence) and five Pb levels. After four months of treatment, the following were analyzed: total and reducing sugars, total phenolic content, flavonoids, antioxidant activity, antioxidant enzymes, proline, and essential oil (EO) content and composition. Soil Pb levels and A. brasilense inoculation affected phytochemicals in lemongrass plants. Azospirillum inoculation reduced total sugars in the roots at all soil Pb levels, while increasing Pb levels favored a rise in sugar contents. There was an increase in flavonoid content in treatments associated with Pb and inoculated with A. brasilense. Antioxidant capacity was lower at lower Pb levels, regardless of bacterial inoculation. Enzymatic response was mainly affected by Pb concentrations between 50 and 100 mg kg-1 soil. EO content was influenced by soil Pb levels, with higher EO production at 500 mg Pb kg-1 soil and without A. brasilense inoculation. Overall, lemongrass cultivation in Pb-contaminated areas can be an alternative to phytoremediation and EO production for the industry.