•Lead is an environmental toxin of great public health concern.•Low, moderate, and high doses of lead were administered orally to rats for one month.•High lead altered the regulation of food intake ...and blood physiology, induced tissue damage mainly liver and kidney, and impaired spatial learning and memory.•Butyryl-L-carnitine and Ganglioside GD2 (d18:0/20:0) levels were significantly reduced at high lead, which is essential for energy production and cellular signalling, respectively.•Pathway enrichment revealed that metabolites were associated with oxidative stress pathways.
Lead is a toxin of great public health concern affecting the young and aging population. Several factors such as age, gender, lifestyle, dose, and genetic makeup result in interindividual variations to lead toxicity mainly due to variations in metabolic consequences. Hence, the present study aimed to examine dose-dependent lead-induced systemic changes in metabolism using rat model by administering specific doses of lead such as 10 (low lead; L-Pb), 50 (moderate lead; M-Pb), and 100 mg/kg (high lead; H-Pb) body weight for a period of one month. Biochemical and haematological analysis revealed that H-Pb was associated with low body weight and feed efficiency, low total protein levels (p ≤ 0.05), high blood lead (Pb-B) levels (p ≤ 0.001), low ALAD (δ-aminolevulinate dehydratase) activity (p ≤ 0.0001), high creatinine (p ≤ 0.0001) and blood urea nitrogen (BUN) (p ≤ 0.01) levels, elevated RBC and WBC counts, reduced haemoglobin and blood cell indices compared to control. Spatial learning and memory test revealed that H-Pb exposed animals presented high latency to the target quadrant and escape platform compared to other groups indicating H-Pb alters cognition function in rats. Histopathological changes were observed in liver and kidney as they are the main target organs of lead toxicity. LC-MS analysis further revealed that Butyryl-L-carnitine (p ≤ 0.01) and Ganglioside GD2 (d18:0/20:0) (p ≤ 0.05) levels were significantly reduced in H-Pb group compared to all groups. Further, pathway enrichment analysis revealed abundance and significantly modulated metabolites associated with oxidative stress pathways. The present study is the first in vivo model of dose-dependent lead exposure for serum metabolite profiling.
► The citrate precursor synthesized in leaching process is Pb(C
6H
6O
7)·H
2O. ► Orthorhombic lead oxide, Pb and amorphous C are the major calcination products of the Pb(C
6H
6O
7)·H
2O in nitrogen ...gas. ► Nanostructured leady oxide powders are obtained at 370
°C for 20 min calcination in air.
As part of contribution for developing a green recycling process of spent lead acid battery, a nanostructural lead oxide was prepared under the present investigation in low temperature calcination of lead citrate powder. The lead citrate, the precursor for preparation of this lead oxide, was synthesized through leaching of spent lead acid battery paste in citric acid solution. Both lead citrate and oxide products were characterized by means of thermogravimetric-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), and scanning electron microscope (SEM). The results showed that the lead citrate was sheet-shape crystal of Pb(C
6H
6O
7)·H
2O. When the citrate was calcined in N
2 gas, β-PbO in the orthorhombic phase was the main product containing small amount of Pb and C and it formed as spherical particles of 50–60
nm in diameter. On combusting the citrate in air at 370
°C (for 20
min), a mixture of orthorhombic β-PbO, tetragonal α-PbO and Pb with the particle size of 100–200
nm was obtained, with β-PbO as the major product. The property of the nanostructural lead oxide was investigated by electrochemical technique, such as cyclic voltammetry (CV). The CV measurements presented the electrochemical redox potentials, with reversibility and cycle stability over 15 cycles.
Little is known about the effects of overall dietary pattern on lead concentration.
We examined the association of overall dietary patterns, derived from a semiquantitative food frequency ...questionnaire, with bone and blood lead concentrations.
These longitudinal analyses included mostly non-Hispanic white, middle-aged-to-elderly men from the Veterans Affairs Normative Aging Study. Long-term lead exposures were measured as tibia and patella lead concentrations by using K-shell-X-ray fluorescence. Short-term lead exposures were measured as blood lead concentrations by using graphite furnace atomic absorption spectroscopy. Dietary pattern scores were derived by using factor analysis. Linear mixed-effects models were utilized to predict blood lead concentrations among 983 men, aged 44-92 y at baseline, with a total of 3273 observations (during 1987-2008). We constructed linear regression models to determine the relations between dietary patterns and bone lead concentrations among 649 participants with an age range of 49-93 y.
Two major dietary patterns were identified: a prudent dietary pattern, characterized by high intakes of fruit, legumes, vegetables, whole grains, poultry, and seafood; and a Western dietary pattern, characterized by high intakes of processed meat, red meat, refined grains, high-fat dairy products, French fries, butter, and eggs. After adjusting for age, smoking status, body mass index, total energy intake, education, occupation, neighborhood-based education and income level, men in the highest tertile of the Western pattern score (compared with the lowest) had 0.91 μg/dL (95% CI: 0.41, 1.42 μg/dL) higher blood lead, 5.96 μg/g (95% CI: 1.76, 10.16 μg/g) higher patella lead, and 3.83 μg/g (95% CI: 0.97, 6.70 μg/g) higher tibia lead. No significant association was detected with the prudent dietary pattern in the adjusted model.
These findings suggest that the Western diet is associated with a greater lead body burden among the middle-aged-to-elderly men. More studies are needed to examine the underlying mechanisms by which dietary patterns are associated with lead concentrations.
Human exposure to lead (Pb) is a growing global public health concern. Elevated blood lead is thought to cause the mental retardation of >0.6 million children globally each year, and has recently ...been attributed to ~18% of all-cause mortality in the US. Due to the severe health risk, the international community, led by the United Nations Environment Programme (UNEP) and the World Health Organization (WHO), is actively supporting the global phase-out of lead-based paint by 2020. However, there are many significant hurdles on the way to achieving this goal. In light of the importance of the lead-based paint issue, and the urgency of achieving the 2020 phase-out goal, this review provides critical insights from the existing scientific literature on lead-based paint, and offers a comprehensive perspective on the overall issue. The global production and international trade of lead-based paints across Asia, Africa, Latin America, and Europe are critically discussed – revealing that lead-based paints are still widely used in many low and middle-income developing countries, and that the production and trade of lead-based paint is still wide-spread globally. In India, as well as many south-east Asian, African, Latin American and European countries, lead concentrations in paints often exceed 10,000 mg/kg. This will certainly pose a serious global threat to public health from surfaces painted with these products for many decades to come. The sources and pathways of exposure are further described to shed light on the associated health risk and socioeconomic costs. Finally, the review offers an overview of the potential intervention and abatement strategies for lead-based paints. In particular, it was found that there is a general lack of consensus on the definition of lead based paint; and, strengthening regulatory oversight, public awareness, and industry acceptance are vital in combating the global issue of lead based paint.
•A summary of the global production and international trade of lead-based paints.•Production and consumption of leaded paint is still growing in developing countries.•A description of sources and pathways of lead paint exposure and associated risks.•An overview of potential intervention and abatement strategies for lead paint.•Greater regulatory oversight, public awareness, and industry acceptance is needed.
Antiferroelectric materials that display double ferroelectric hysteresis loops are receiving increasing attention for their superior energy storage density compared to their ferroelectric ...counterparts. Despite the good properties obtained in antiferroelectric La‐doped Pb(Zr,Ti)O3‐based ceramics, lead‐free alternatives are highly desired due to the environmental concerns, and AgNbO3 has been highlighted as a ferrielectric/antiferroelectric perovskite for energy storage applications. Enhanced energy storage performance, with recoverable energy density of 4.2 J cm−3 and high thermal stability of the energy storage density (with minimal variation of ≤±5%) over 20–120 °C, can be achieved in Ta‐modified AgNbO3 ceramics. It is revealed that the incorporation of Ta to the Nb site can enhance the antiferroelectricity because of the reduced polarizability of B‐site cations, which is confirmed by the polarization hysteresis, dielectric tunability, and selected‐area electron diffraction measurements. Additionally, Ta addition in AgNbO3 leads to decreased grain size and increased bulk density, increasing the dielectric breakdown strength, up to 240 kV cm−1 versus 175 kV cm−1 for the pure counterpart, together with the enhanced antiferroelectricity, accounting for the high energy storage density.
AgNbO3 lead‐free antiferroelectric ceramic is reported to be a promising candidate for energy storage applications. A great breakthrough with high recoverable energy density up to 4.2 J cm−3 and good thermal stability with minimal variation (±5%) over a temperature range of 20–120 °C is achieved in Ta‐modified AgNbO3 ceramics. This is possible because of the enhanced dielectric breakdown strength and antiferroelectricity.
► Biogeochemical behavior of Pb strongly depends on its chemical speciation. ► Organic ligands modify Pb speciation and in turns, its biogeochemical behavior. ► Effect of organic ligand on Pb ...behavior vary with soil characteristics. ► Efficiency of organic ligands to modify Pb behavior vary with their binding capacity.
Biogeochemical behavior of lead (Pb), a persistent hazardous pollutant of environmental concern, strongly depends on its chemical speciation. Therefore, in this review, link between Pb speciation: presence of organic ligands and its environmental behavior has been developed. Both, biogeochemical and ecotoxicological data are discussed in environmental risk assessment context and phytoremediation studies. Three kinds of organic ligands selected for this review include: (1) ethylene diamine tetra-acetic acid (EDTA), (2) low molecular weight organic acids (LMWOAs) and (3) humic substances (HSs). The review highlights the effect of Pb speciation on: (i) Pb fate and behavior in soil; (ii) Pb plant uptake and accumulation in different plant parts; and (iii) Pb-induced phyto-toxicity. Effects of organic ligands on Pb speciation are compared: how they can change Pb speciation modifying accordingly its fate and biogeochemistry in soil-plant system? EDTA forms soluble, stable and phytoavailable Pb-chelates due to high binding Pb affinity. LMWOAs can solubilize Pb in soil by decreasing soil pH or increasing soil organic contents, but have little effect on its translocation. Due to heterogeneous structure, HSs role is complex. In consequence Pb speciation knowledge is needed to discuss phyto-toxicity data and improved soil phytoremediation techniques.
In 2012, the Centers for Disease Control and Prevention (CDC) adopted its Advisory Committee on Childhood Lead Poisoning Prevention recommendation to use a population-based reference value to ...identify children and environments associated with lead hazards. The current reference value of 5 μg/dL is calculated as the 97.5th percentile of the distribution of blood lead levels (BLLs) in children 1 to 5 years old from 2007 to 2010 NHANES data. We calculated and updated selected percentiles, including the 97.5th percentile, by using NHANES 2011 to 2014 blood lead data and examined demographic characteristics of children whose blood lead was ≥90th percentile value. The 97.5th percentile BLL of 3.48 µg/dL highlighted analytical laboratory and clinical interpretation challenges of blood lead measurements ≤5 μg/dL. Review of 5 years of results for target blood lead values <11 µg/dL for US clinical laboratories participating in the CDC's voluntary Lead and Multi-Element Proficiency quality assurance program showed 40% unable to quantify and reported a nondetectable result at a target blood lead value of 1.48 µg/dL, compared with 5.5% at a target BLL of 4.60 µg/dL. We describe actions taken at the CDC's Environmental Health Laboratory in the National Center for Environmental Health, which measures blood lead for NHANES, to improve analytical accuracy and precision and to reduce external lead contamination during blood collection and analysis.
•We performed a cross-sectional survey in 122 metallurgic refinery workers.•We assessed the effect of co-exposure to Cd and Pb on early renal biomarkers.•The exposure to Cd and Pb was low to ...moderately high, respectively.•Pb increases the strength of the association between Cd and renal biomarkers.
Research on the effect of co-exposure to Cd and Pb on the kidney is scarce. The objective of the present study was to assess the effect of co-exposure to these metals on biomarkers of early renal effect.
Cd in blood (Cd-B), Cd in urine (Cd-U), Pb in blood (Pb-B) and urinary renal biomarkers, i.e., microalbumin (μ-Alb), beta-2-microglobulin (β2-MG), retinol binding protein (RBP), N-acetyl-β-d-glucosaminidase (NAG), intestinal alkaline phosphatase (IAP) were measured in 122 metallurgic refinery workers examined in a cross-sectional survey.
The median Cd-B, Cd-U, Pb-B were: 0.8μg/l (IQR=0.5, 1.2), 0.5μg/g creatinine (IQR=0.3, 0.8) and 158.5μg/l (IQR=111.0, 219.3), respectively. The impact of Cd-B on the urinary excretion of NAG and IAP was only evident among workers with Pb-B concentrations ≥75th percentile. The association between Cd-U and the renal markers NAG and RBP was also evidenced when Pb-B ≥75th percentile. No statistically significant interaction terms were observed for the associations between Cd-B or Cd-U and the other renal markers under study (i.e., μ-Alb and β2-MG). Our findings indicate that Pb increases the impact of Cd exposure on early renal biomarkers.
Giant electric‐field–induced strain of 0.70%, corresponding to a d33* value of 1400 pm V−1, is observed in a lead‐free (Bi1/2Na1/2)TiO3‐based polycrystalline ceramic. This is comparable to the ...properties of single crystals. An in situ transmission electron microscopy study indicates that the excellent performance originates from phase transitions under the applied electric fields.
•This review article discusses in detail the health effects in humans due to long-term exposure to lead.•The article also illustrates the complications when the blood lead level in both men and women ...is more.•The oxidative stress that occurs in the human cells causing severe cell damage has also been discussed.•Finally, the preventive measures and the treatment for lead toxicity and lead accumulation have been discussed along with chelation therapy.
Lead is a prevalent heavy metal that pollutes the environment and accumulates in the human body via absorption, bioavailability, bioconcentration, and biomagnification disrupts the neurological, skeletal, reproductive, hematopoietic, renal, and cardiovascular systems. Lead's distinctive physical and chemical characteristics make it ideal for a variety of uses. It has been linked to human activities for ages and is harmful to health. This review article examines the long-term health consequences of lead exposure in humans. Acute and chronic symptoms of lead poisoning include kidney, brain, reproductive organ, and CNS/PNS damage. Toxic metals have a long half-life in the bone matrix and brain (2–3 years), causing neurological problems and bone loss. The article also shows the problems of high BPb in both men and women during pregnancy. Renal system blood lead levels of 30–60 g/dL may cause kidney failure in severe circumstances. The oxidative stress that occurs in human cells has also been explored. Finally, lead poisoning and lead buildup prevention and therapy have been reviewed. The use of micronutrients and antioxidants has demonstrated a reduction in harmful effects. Adults with BPb >45 g/dL should have chelation, whereas children should receive succimer.
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