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An extensive validation of a rapid and direct sampling method was done for estimation of lead content in whole blood using graphite tube atomizer atomic absorption spectroscopy without pre-digestion. The sequence of sample introduction and amount of addition of a mixed matrix modifier solution is conceded here. The current method is optimized and rigorously validated within the commonly disseminated lead toxicity range on whole blood samples without a tedious step of sample preparation and/or digestion. Multivariate optimization and validation were used to establish the optimal conditions of the graphite tube atomizer and matrix modifier solution for blood lead detection. No significant differences were found between the results obtained using the proposed method and the optimized mixed matrix modifier solution for the lead analyte estimation in whole blood matrix. [ABSTRACT FROM AUTHOR]

Lead (Pb) is one of the most abundant toxic metals in the environment that can cause a variety of harmful effects. During embryonic development of vertebrates, somites are temporary organs that give rise to skeletal muscle, cartilage, tendon, endothelial cells, and dermis. In this study, we investigated the effects of lead on the development of somites and their derivatives in chick embryos under in vitro conditions. For this propose, fertilized eggs of Gallus gallus domesticus were incubated until they reached the stage of 15–20 somites. The somites and notochord were isolated and treated with different concentrations of lead acetate (500, 1000, 2000, and 4000 ng ml−1) for 72 h. Our results indicated that high concentrations of lead reduced the nucleus diameter, reduced the synthesis of collagen, inhibited the formation of the cartilage matrix in somite cells, and disturbed the formation and order of myotubes. In conclusion, the results of the current study for the first time indicated the disturbing effects of lead on the development of somites in the chick embryo. Our results revealed that lead disturbed the development of somites in the chick embryo, which suggested that at high concentrations it can cause a serious mortal danger to life. [ABSTRACT FROM AUTHOR]

Abstract 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. Highlights • 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. [ABSTRACT FROM AUTHOR]

Lead wheel weights (LWWs) have been banned in Europe, and some US States, but they continue to dominate the market in Canada. Exposure to lead is associated with numerous health impacts and can result in multiple and irreversible health problems which include cognitive impairment when exposure occurs during early development. Such impacts incur high individual and social costs. The purpose of this study was to assess the costs and public health benefits of a Risk Management Strategy (RMS) that would result from a LWW phase-out in Canada and compare this to a Business-As-Usual (BAU) scenario. The contribution of LWWs to lead concentrations in media including roadway soil/dust, ambient and indoor air, and indoor dust were estimated. The Integrated Exposure Uptake Biokinetic Model for Lead in Children (IEUBK) was used to develop estimates for the blood lead levels (BLLs) in children (μg/dL) associated with the BAU and the RMS. The BLLs estimated via the IEUBK model were then used to assess the IQ decrements associated with the BAU that would be avoided under the RMS. The subsequent overall societal benefits in terms of increased lifetime earning potential and reduced crime rate, were then estimated and compared to industry and government costs. LWWs form 72% of the Canadian wheel weight market and >1500 tonnes of lead as new LWWs attached to vehicles enters Canadian society annually. We estimate that 110–131 tonnes of lead in detached WWs are abraded on roadways in Canada each year. A LWW phase-out was predicted to result in a drop in pre-school BLLs of up to 0.4 μg/dL. The estimated net benefits associated with the RMS based on cognitive decrements avoided and hence increased lifetime earning potential (increased productivity) and reduced crime are expected to be: C$248 million (8% discount rate) to C$1.2 billion (3% discount rate) per year. [ABSTRACT FROM AUTHOR]

Background Lead and mercury are freely transferred across the placenta, while cadmium tends to accumulate in the placenta. Each contributes to adverse neurological outcomes for the child. Although prenatal heavy metal exposure has been linked with an array of neurodevelopmental outcomes in childhood, its association with the development of motor skills in children has not been robustly studied. Aims/objective The aim of the present study was to investigate the association between prenatal exposure to lead, cadmium and mercury, measured as maternal blood concentrations during pregnancy, and motor skills, measured as subtests of the Movement Assessment Battery for Children (Movement ABC) at age 7 years in a large sample of mother–child pairs enrolled in a UK observational birth cohort study (Avon Longitudinal Study of Parents and Children, ALSPAC). Methods Whole blood samples from pregnant women enrolled in ALSPAC were analysed for lead, cadmium and mercury. In a complete case analysis (n = 1558), associations between prenatal blood concentrations and child motor skills assessed by Movement ABC subtests of manual dexterity, ball skills and balance at 7 years were examined in adjusted regression models. Associations with probable developmental coordination disorder (DCD) were also investigated. Results The mean prenatal blood levels were: lead 3.66 ± 1.55 μg/dl; cadmium 0.45 ± 0.54 μg/l; mercury 2.23 ± 1.14 μg/l. There was no evidence for any adverse associations of prenatal lead, cadmium or mercury exposure with motor skills measured at age 7 years with Movement ABC subtests in adjusted regression models. Further, there were no associations with probable DCD. Conclusions There was no evidence to support a role of prenatal exposure to heavy metals at these levels on motor skills in the child at age 7 years measured using the Movement ABC. Early identification of symptoms of motor skills impairment is important, however, to enable investigation, assessment and treatment. [ABSTRACT FROM AUTHOR]

Summary: Lead (Pb) is a nonthreshold multi‐targeted toxicant that causes alterations in different organs of the body, especially the gonads. This study was aimed to investigate the possible protective effect of thymoquinone (TQ), the major active ingredient of volatile oil of Nigella sativa seeds, against Pb‐induced testicular histological damage. Adult male rats were randomised into four groups as follows: control group received no treatment, Pb group was exposed to 2000 ppm of Pb acetate in drinking water, Pb‐TQ group was cotreated with Pb plus TQ (5 mg/kg/day, per os) and TQ group receiving only TQ. All treatments were applied for five weeks. Results showed that Pb exposure produced morphological changes in the testis, especially degeneration of germinal epithelium, sloughing of germ cells into the lumen of seminiferous tubules and reduction in the number of luminal spermatozoa. Interestingly, coadministration of TQ to the metal‐treated animals prevented the testicular adverse effects. In conclusion, our data indicate for the first time a remarkable protective effect of TQ against Pb‐induced testicular histopathological lesions in rat. On this basis, TQ deserves more consideration and further examination as a potential therapeutic option. [ABSTRACT FROM AUTHOR]

Lead (Pb2+) is a poisonous heavy metal that causes many pathophysiological effects in living systems. Its toxicological effects are well known as it causes apoptosis of several cell types and tissues. This study aimed to determine the criteria required for early diagnosis of Pb2+poisoning in the Siberian tiger using a tiger population in China, to identify a safety Pb2+concentration threshold, and to provide suggestions for preventing Pb2+poisoning in Siberian tigers. We investigated the apoptotic effects of Pb2+(0, 32, 64, and 125 μM) for 12–48 h on Siberian tiger fibroblastsin vitro. Typical apoptotic effects were observed after Pb2+exposure. Pb2+strongly blocked DNA synthesis in the G0/G1 phase and induced cell apoptosis in a dose- and time-dependent manner. Intracellular free calcium (Ca2+) levels, reactive oxygen species levels, and efflux of extracellular Ca2+were increased. The mitochondrial membrane potential was lowered. Caspase-3, -8, and -9 activities were increased when fibroblasts were treated with 32, 64, and 125 μM Pb2+. The gene expression levels of Bax, caspase-3, -8, Fas, and p53 were increased, while that of Bcl-2 was decreased. Calcium homeostasis and mitochondrial function were disturbed. Ca2+efflux, oxidative damage, activation of caspases, and regulation of Bax, Bcl-2, caspase-3, -8, Fas, and p53 gene expression played an important role in the apoptotic effects. The disorder of intracellular homeostasis was the trigger for apoptosis in Siberian tiger fibroblasts. [ABSTRACT FROM PUBLISHER]

The current study was undertaken to determine the concentration of Hg and Pb in ten types of collected green leafy vegetables and herbs from different agricultural sites of Markazi province, Iran as well as the gathered water and soil around them using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, the potential health risk assessment by using target hazard quotient (THQ) and hazard index (HI) parameters was estimated. Based on the accumulation order, Artemisia dracunculus L with 56.147 ± 17.30 μg/kg and Spinacia oleracea L with 1733.62 ± 2264.7 μg/kg can uptake and accumulate more concentration of Pb and Hg in their tissues, respectively. Regarding gathered soil around vegetables, the concentration of Hg and Pb were measured as 52.056 ± 16.25 μg/kg and 4993.83 ± 1287.8 μg/kg, respectively. The transfer factor (TF) demonstrated that vegetables and herbs could absorb a high amount of Hg from the soil while these plants uptake less concentration of Pb thought their green leaves. The non-carcinogenic risk assessment showed the minimum, and maximum THQ was related to 15–24 and 35–44 age groups in the urban and rural consumers. Also, HI in the urban and rural areas was calculated as 8.492 and 9.012, respectively. Since HI > 1, exposure of the urban and rural areas of Markazi province to non-carcinogenic risk by consuming the green leafy vegetables and herbs is a source of concern. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate toxicological risks for workers who are exposed to lead in their work environment. Methods: Since it is an important indicator of toxicological risk, a statistical analysis of lead concentration and biological lead toxicity markers in blood and urine were performed for both exposed and control groups. Both experimental groups consisted of employees from "NISSAL" JSC factory. Analytical epidemiological method in the form of a retrospective cohort study was applied, and covered the period from 2001 to 2010. The concentration of lead, δ-aminolevulinic acid, and coproporphyrin in biological samples were determined by spectrophotometric methods. Results: The results showed a high positive correlation between lead concentrations in blood and urine and the length of exposure of the participants (p < 0.01). Also, increase of lead concentration in the biological material significantly increased δ-aminolevulinic acid (p < 0.01) and slightly increased the concentration of coproporphyrin, both of which are important indicators of toxicological risk. Conclusion: The control group of employees belonged to the normal risk category, while the exposed group belonged to a moderate risk category. Correlation between the monitored parameters is statistically significant at p < 0.01 and p < 0.05. [ABSTRACT FROM AUTHOR]

Lead exposure has been reported to produce many clinical features, including parkinsonism. However, its consequences on the circadian rhythms are still unknown. Here we aimed to examine the circadian rhythms of locomotor activity following lead intoxication and investigate the mechanisms by which lead may induce alterations of circadian rhythms in rats. Male Wistar rats were injected with lead or sodium acetate (10 mg/kg/day, i.p.) during 4 weeks. Both groups were tested in the "open field" to quantify the exploratory activity and in the rotarod to evaluate motor coordination. Then, animals were submitted to continuous 24 h recordings of locomotor activity under 14/10 Light/dark (14/10 LD) cycle and in complete darkness (DD). At the end of experiments, the clock proteins BMAL1, PER1-2, and CRY1-2 were assayed in the suprachiasmatic nucleus (SCN) using immunohistochemistry. We showed that lead significantly reduced the number of crossing in the open field, impaired motor coordination and altered the daily locomotor activity rhythm. When the LD cycle was advanced by 6 h, both groups adjusted their daily locomotor activity to the new LD cycle with high onset variability in lead-intoxicated rats compared to controls. Lead also led to a decrease in the number of immunoreactive cells (ir-) of BMAL1, PER1, and PER2 without affecting the number of ir-CRY1 and ir-CRY2 cells in the SCN. Our data provide strong evidence that lead intoxication disturbs the rhythm of locomotor activity and alters clock proteins expression in the SCN. They contribute to the understanding of themechanismby which lead induce circadian rhythms disturbances. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a toxic environmental pollutant that induces a broad range of biochemical and physiological hazards in living organisms. We investigated the possible hepatoprotective effects of Spirulina platensis (SP) in counteracting the Pb-induced oxidative damage. Ninety-six adult African catfish were allocated into four equal groups. The 1st group (control) fed basal diet while the 2nd group (Pb-treated) fed on basal diet and exposed to 1 mg Pb(NO 3 ) 2 /L. The 3rd and 4th groups fed SP-supplemented basal diets at levels of 0.25% and 0.5%, respectively and exposed to Pb. Serum samples were used to analyze hepatic function biomarkers, electrolytes, and oxidant and antioxidant status. Lipid peroxidation and DNA fragmentation were determined in the liver tissues. Pb exposure induced hepatic dysfunction, electrolytes (Na + , K + , Ca +2 , and Cl - ) imbalance, as well a significant decrease in GSH content, and LDH, AChE, SOD, CAT and GST enzymes activity. SP supplementation reverted these biochemical and genetic alterations close to control levels. This amelioration was higher with 0.5% SP and at the 4th week of exposure, showing concentration- and time-dependency. Thus, the current study suggests that SP could protect the catfish liver against lead-induced injury by scavenging ROS, sustaining the antioxidant status and diminishing DNA oxidative damage. The dietary inclusion of SP can be used as a promising protective agent to counteract oxidative stress-mediated diseases and toxicities. [ABSTRACT FROM AUTHOR]

Airborne lead and acidic gasses are generated through combustion and mechanical abrasion of ammunition constituents during shooting events. Shooters and other personnel at shooting ranges are exposed to these airborne toxicants and the potential health risks of irritation, nervous system damage, and cancer. Past studies primarily focused on full-length work-shift exposure to lead with little research examining short-term task-based exposure. The objective of this study was to measure the shooters’ task-based personal exposure to total fume, lead, and acidic gasses during two-hour shooting sessions at indoor and outdoor shooting ranges. Both pistols and rifles were used, and about 180 rounds of ammunition were fired per shooting session. Total fume was collected by inhalable and respirable fractions and determined gravimetrically. Airborne lead and acidic gasses were analyzed using an inductively coupled plasma mass spectrometer and an ion chromatograph, respectively. The results indicated that significant amount of aerosol mass was in the respirable fraction (0.4–2.8 mg/m 3 ) and inhalable fraction (0.6–3.5 mg/m 3 ). The respirable airborne lead concentration during two-hour shooting sessions was between 0.2 and 1.7 mg/m 3 , although not directly comparable, were exceeding the Occupational Safety and Health Administration 8-h time-weighted-average permissible exposure limit (PEL) of 0.05 mg/m 3 . Hydrochloric acid was detected at levels lower than the PEL, during some outdoor shooting sessions possibly due to the presence of corrosive ammunitions. Sulfuric acid was detected and above the PEL during outdoor shooting sessions, but potential measurement artifacts exist in the standard method. Indoor ventilation effectively removed gaseous pollutants, but unable to migrate the particulate fume and lead exposure to acceptable levels. Outdoor ventilation relied more upon natural weather and had a larger deviation. Rifle shooting produced more exposure than did pistol shooting, but the finding was reversed after the exposure was adjusted to ammunition propellant loadings. The present study confirmed the shooter's exposure to airborne lead and some acidic gasses at levels higher than comparable PEL values. More engineering controls and administrative management should be sought to prevent overexposure to these airborne toxicants. [ABSTRACT FROM AUTHOR]

Background: Lead-exposed workers may suffer adverse health effects under the currently regulated blood lead (BPb) levels. However, a probabilistic assessment about lead exposure-associated anemia risk is lacking. The goal of this study was to examine the association between lead exposure and anemia risk among factory workers in Taiwan.Methods: We first collated BPb and indicators of hematopoietic function data via health examination records that included 533 male and 218 female lead-exposed workers between 2012 and 2014. We used benchmark dose (BMD) modeling to estimate the critical effect doses for detection of abnormal indicators. A risk-based probabilistic model was used to characterize the potential hazard of lead poisoning for job-specific workers by hazard index (HI). We applied Bayesian decision analysis to determine whether BMD could be implicated as a suitable BPb standard.Results: Our results indicated that HI for total lead-exposed workers was 0.78 (95% confidence interval: 0.50-1.26) with risk occurrence probability of 11.1%. The abnormal risk of anemia indicators for male and female workers could be reduced, respectively, by 67-77% and 86-95% by adopting the suggested BPb standards of 25 and 15 μg/dL.Conclusions: We conclude that cumulative exposure to lead in the workplace was significantly associated with anemia risk. This study suggests that current BPb standard needs to be better understood for the application of lead-exposed population protection in different scenarios to provide a novel standard for health management. Low-level lead exposure risk is an occupational and public health problem that should be paid more attention. [ABSTRACT FROM AUTHOR]

It is well-known that occupational and environmental exposure to several factors, including benzene, heavy metals, chemicals and mineral fibers, is associated with the risk of developing a great number of diseases. Numerous studies have been carried out in order to investigate the mechanisms of toxicity of these substances, with particular regard to the possible toxic effects on the immune system. However, little is known about the influence of heavy metals, such as lead, on the immune system in human populations. Lead is a heavy metal still used in many industrial activities. Human exposure to lead can induce various biological effects depending upon the level and duration of exposure, such as toxic effects on haematological, cardiovascular, nervous and reproductive systems. Several studies demonstrated that exposure to lead is associated to toxic effects also on the immune system, thus increasing the incidence of allergy, infectious disease, autoimmunity or cancer. However, the effects of lead exposure on the human immune system are not conclusive, mostly in occupationally exposed subjects; nevertheless some immunotoxic abnormalities induced by lead have been suggested. In particular, in vivo, in vitro and ex vivo lead is able to improve T helper 2 (Th2) cell development affecting Th1 cell proliferation. Further studies are required to better understand the mechanisms of lead immunotoxicity and the ability of lead to affect preferentially one type of immune response. [ABSTRACT FROM AUTHOR]

Blood lead level is associated with increased risk of mortality, but dietary lead exposure and mortality, particularly with cancer, has not been studied in the general population. The objective of the study was to assess the association between lead intake and 10-year mortality among 2832 Chinese adults. Food intake was measured by 3-day weighed food record in 2002. We documented 184 deaths (63 cancer deaths and 70 cardiovascular disease (CVD) deaths) during 27,742 person-years of follow-up. Dietary lead intake was positively associated with cancer and all-cause mortality. Across quartiles of lead intake, hazard ratios (HRs) for cancer mortality were 1.00, 0.80 (0.33-1.92), 1.52 (0.65-3.56), and 3.00 (1.06-8.44) ( p for trend 0.028). HRs for all-cause mortality were 1.00, 1.28 (0.83-1.98), 1.24 (0.78-1.97), and 2.24 (1.28-3.94) ( p for trend 0.011). Each 30 μg/day increase of lead intake was associated with 25% (95% CI 3-52%) increase of all-cause mortality. There was an interaction between lead intake and hypertension in relation to CVD mortality ( p for interaction 0.003): HRs conferred by every 30 μg/day of lead intake were 1.57 (0.98-2.52) and 1.06 (0.81-1.39) among those with or without hypertension. Dietary lead intake was positively related to cancer and all-cause mortality. [ABSTRACT FROM AUTHOR]

Lead (Pb) is one of the most common heavy metals in nature which has an adverse effect on aquatic ecosystems and affects animal health. Animal survival depends on its reproductive ability. To analyse the influence of Pb on the male testis tissues in the spot frog (Pelophylax nigromaculata), the male adult individuals were exposed to Pb (10, 100 and 1000 μg/L) in water for 30 days. We observed the spermatic histopathologic structure and detected the expression and location of androgen receptors (AR) on the germ cells by immunohistochemical method. Compared to the control, the testis histopathologic structure and the expression of AR at Pb treatment were different. At relatively higher concentration (100 and 1000 μg/L), the changes of spermatic pathological mainly included germ cell necrosis, congestion and fibrosis congestion. The expressions of AR on the gonad cells were affected by Pb. With the increase of Pb concentration, AR expressions were decreased. [ABSTRACT FROM AUTHOR]

Adverse health effects of heavy metals are a public health concern, especially lead may cause negative health impacts to human fetal and infantile development. The lead concentrations in Pakistani pregnant women's nails, used as a biomarker, were measured to estimate the lead exposure. Thirteen nail samples out of 84 nails analyzed contained lead higher than the concentration (13.6 μg/g) of the fatal lead poisoning case, raising the possibility of an external contamination. Eye cosmetics such as surma are recognized as one of the important sources of lead exposure in Pakistan. We collected in Pakistan 30 eye cosmetics made in Pakistan, Saudi Arabia and western countries. As the metal composition analysis by energy dispersive X-ray fluorescence spectrometry revealed that some surma samples contained lead more than 96%, the surma might contaminate the nail specimen. Scanning electron microscopy observations showed that lead-containing surma consists of fine particle of galena (ore of lead sulfide) in respirable dust range (less than 10 μm). In addition, relative in vitro bioavailability of lead in the surma was determined as 5.2%. Thus, lead-containing surma consists of inhalable and bioavailable particles, and it contributes an increased risk of lead exposure. Moreover, the relationship between the surma and the lead-contaminated nails by lead isotope ratios analysis indicated the potential of lead contamination in nails by surma. These results suggest that lead in the nails was derived both from body burden of lead and external contamination by lead-containing surma. Therefore, nail is not suited as a biomarker for lead exposure in the countries where surma used, because we may overestimate lead exposure by surface lead contamination in the nail by surma. [ABSTRACT FROM AUTHOR]

Lead, a chemical element in the carbon group with symbol Pb (from Latin: Plumbum, meaning "the liquid silver") and has an atomic number 82 in the periodic table. It was the first element that was characterized by its kind of toxicity. In animal systems, lead (Pb) has been incriminated in a wide spectrum of toxic effects and it is considered one of the persistent ubiquitous heavy metals. Being exposed to this metal could lead to the change of testicular functions in human beings as well as in the wildlife. The lead poising is a real threat to the public health, especially in the developing countries. Accordingly, great efforts on the part of the occupational and public health have been taken to curb the dangers of this metal. Hematopoietic, renal, reproductive, and central nervous system are among the parts of the human body and systems that are vulnerable toward the dangers following exposure to high level of Pb. In this review, we discussed the massive harmful impact that leads acetate toxicity has on the animals and the worrying fact that this harmful toxicant can be found quite easily in the environment and abundance. Highlighting its (Pb) effects on various organs in the biological systems, its economic, as well as scientific importance, with the view to educate the public/professionals who work in this area. In this study, we focus on the current studies and research related to lead toxicity in animals and also to a certain extent toward human as well. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a widespread toxic metal found in the environment with potential danger to human health. It is used in the manufacture of batteries, metal products, paints and other domestic substances. This study investigated the effect of aqueous seed extract of Nigella sativa on leadinduced cerebral cortex toxicity in Long Evan's rats. Twenty five Long Evans rats divided into five groups of five animals were used for the study. Group I received Distilled water, group II received aqueous seed extract of Nigella sativa (1000mg/kg), group III received lead (60mg/kg), group IV received lead (60mg/kg) followed by aqueous seed extract of Nigella sativa (1000mg/kg) and group V received lead (60mg/kg) followed by aqueous seed extract of Nigella sativa (500mg/kg) via oral intubation. Elevated Plus Maze (EPM) was used to study anxiety-like behaviour. Activities on the elevated plus maze showed that there was no statistically significant decreased rate of anxiety across the groups (P>0.05). The histology of the cerebral cortex of long Evans rats in group IV that received Lead (60 mg/kg) followed by aqueous seed extract of Nigella sativa (1000mg/kg) showed mild neuronal damage while the histology of group V animals that received lead (60mg/kg) followed by aqueous seed extract of Nigella sativa (500mg/kg) showed severe neuronal damage. It can be concluded that aqueous seed extract of Nigella sativa at high dose have more therapeutic effect than at low dose. [ABSTRACT FROM AUTHOR]

DNAzyme based electrochemical biosensors have the characteristics of high sensitivity and selectivity, but traditional DNAzyme based electrochemical biosensors need the immobilization of DNAzyme on the electrode surface first, and the procedures are time consuming and tedious, which limit their real application. In this study, a simple but sensitive immobilization free DNAzyme based electrochemical biosensor has been proposed and lead has been chosen as a model target because of the severe effects of lead toxicity. The different diffusivity and electrostatic repulsion between long and short DNA on the negatively charged ITO electrode can be used to discriminate the short and long DNA. Lead dependent DNAzyme was hybridized with its substrate (which was modified with methylene blue at the 3′ terminal) beforehand. Since the DNAzyme/substrate complex contains a large negative charge, it cannot diffuse easily to the negatively charged ITO electrode surface and little electrochemical signal has been detected. The presence of lead would trigger the cleavage of the DNAzyme/substrate complex and cause the release of a methylene blue-labeled short-oligonucleotide into the solution. The methylene blue-labeled short-oligonucleotide can diffuse easily to the surface of the negatively charged ITO electrode and results in the enhanced electrochemical response being detected. Each lead can cleave a lot of DNAzyme/substrate complex to realize signal amplification. The enhanced electrochemical signal has a linear relationship with the Pb2+ concentration in the range of 0.05–1 μM with a detection limit of 0.018 μM (S/N = 3). The proposed biosensor has been applied to detect Pb2+ in water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Lead is a neurotoxin that has been documented to affect many forms of wildlife, and has been identified as a limiting factor in a population of California Condors in Northern Arizona. The Arizona Game and Fish Department provides vouchers for free nonlead ammunition to hunters selected to hunt within the distribution of California Condors, with the intention of having fewer lead-laden offal piles available to California Condors. Although wildlife agencies may reasonably assume voucher programs motivate hunters into choosing nonlead ammunition, the lead reduction efforts attributable to the voucher program has not been empirically quantified. Our intention was to compare a control group of hunters to a treatment group of hunters within California Condor occupied areas. Both groups received educational materials regarding the deleterious effects of lead, but the treatment group also received a voucher for a free initial box of ammunition. About half of the control group used nonlead ammunition, compared to about three-fourths of the treatment group. Prominent barriers to adoption of nonlead ammunition included a general difficulty of obtaining it, obtaining it in the desired caliber, and its costliness. Frequently mentioned motivations for using nonlead was the exhortation to use it by the Department, and the desire to aid California Condor recovery by hunters. The disparate compliance rates found herein confirm and quantify the success of nonlead ammunition voucher programs, but underscore the importance of working to increase the supply of nonlead ammunition with the end of facilitating its procurement and reducing its cost. [ABSTRACT FROM AUTHOR]

Numerous experiments under controlled conditions and extensive investigation of waterfowl die-offs have demonstrated that exposure to lead from spent gunshot is highly detrimental to the health of waterfowl. However, few studies have focused on examining the more subtle sub-lethal effects of lead toxicity on ducks in non-experimental settings. In our study, the health of ducks exposed to varying amounts of lead under natural conditions was assessed by correlating individual lead exposure with relevant indices of health. Based on hunter-killed wild ducks in Argentina, we measured spleen mass, body condition, examined bone marrow smears, and determined Ca and P in bone tissue. In free-ranging live-trapped ducks we determined basic hematology and aminolevulinic acid dehydratase activity. Using multivariate analyses, we found that, when controlling for the potential confounding effect of site type, year, duck species, body mass and age, lead levels in the liver were negatively associated with body condition and spleen mass. Spleen mass was also lower in ducks with higher lead levels in their bones. In live ducks, high blood lead levels were associated with low packed cell volume and red cell morphologic abnormalities. These findings suggest that, despite the lack of recorded lead-induced mortality in the region, lead exposure results in less conspicuous but still significant impacts on the health of ducks, which could have serious implications for their conservation. Moreover, this evidence further supports the need for urgently banning lead shot in the region. [ABSTRACT FROM AUTHOR]

In Brazil there is no systematic evaluation to access blood lead levels (BLL) in the general population and few studies with adults have been published. The aim of this study was to examine the socioeconomic, environmental, and lifestyle determinants of BLL in the adult Brazilian population. In total, 959 adults, aged 40 years or more, were randomly selected in a city in southern Brazil. Information on socioeconomic, dietary, lifestyle, and occupational background was obtained by interviews. A spatial analysis was conducted to discern whether there were any identifiable sources of exposure. BLL were measured by inductively coupled plasma–mass spectrometry. There was an adjustment for gender, age, race, education, income class, smoking status, alcohol consumption, occupation, and red meat or cow milk consumption (Model 1), and for occupation and gender (Model 2). The geometric mean of BLL was 1.97 μg/dl (95% CI: 1.9–2.04 μg/dl). In Model 1, BLL were positively associated with male gender, older age, and drinking and smoking habits, and less frequently with milk consumption. In Model 2, data showed higher BLL in non-white than white participants, in former smokers and individuals with current or former employment in lead (Pb) industries. The participants living in the area with more Pb industries had higher BLL (3.3 μg/dl) compared with those residing in other areas with no or fewer Pb industries (1.95 μg/dl). Despite the low BLL found in adults living in an urban area, Pb industries need to be monitored and regulatory laws implemented to prevent metal contamination in urban settings. [ABSTRACT FROM PUBLISHER]

Background Although the association between lead and cardiovascular disease is well established, potential mechanisms are still poorly understood. Calcium metabolism plays a role in lead toxicity and thus, vitamin D receptor (VDR) polymorphisms have been suggested to modulate the association between lead and health outcomes. We investigated effect modification by VDR genetic polymorphisms in the association between cumulative lead exposure and pulse pressure, a marker of arterial stiffness. Methods We examined 727 participants (3,100 observations from follow-ups from 1991 to 2011) from the Normative Aging Study (NAS), a longitudinal study of aging. Tibia and patella bone lead levels were measured using K-x-ray fluorescence. Four single nucleotide polymorphisms (SNPs) in the VDR gene, Bsm1, Taq1, Apa1, and Fok1, were genotyped. Linear mixed effects models with random intercepts were implemented to take into account repeated measurements. Results Adjusting for potential confounders, pulse pressure was 2.5 mmHg (95% CI: 0.4-4.7) and 1.9 mmHg (95% CI: 0.1-3.8) greater per interquartile range (IQR) increase in tibia lead (15 μg/g) and patella lead (20 μg/g), respectively, in those with at least one minor frequency allele in Bsm1 compared with those with major frequency allele homozygotes. The observed interaction effect between bone lead and the Bsm1 genotype persists over time during the follow-up. Similar results were observed in effect modification by Taq1. Conclusions This study suggests that subjects with the minor frequency alleles of VDR Bsm1 or Taq1 may be more susceptible to cumulative lead exposure-related elevated pulse pressure. [ABSTRACT FROM AUTHOR]

Interior Antarctica is among the most remote places on Earth and was thought to be beyond the reach of human impacts when Amundsen and Scott raced to the South Pole in 1911. Here we show detailed measurements from an extensive array of 16 ice cores quantifying substantial toxic heavy metal lead pollution at South Pole and throughout Antarctica by 1889 - beating polar explorers by more than 22 years. Unlike the Arctic where lead pollution peaked in the 1970s, lead pollution in Antarctica was as high in the early 20th century as at any time since industrialization. The similar timing and magnitude of changes in lead deposition across Antarctica, as well as the characteristic isotopic signature of Broken Hill lead found throughout the continent, suggest that this single emission source in southern Australia was responsible for the introduction of lead pollution into Antarctica at the end of the 19th century and remains a significant source today. An estimated 660 t of industrial lead have been deposited over Antarctica during the past 130 years as a result of mid-latitude industrial emissions, with regional-to-global scale circulation likely modulating aerosol concentrations. Despite abatement efforts, significant lead pollution in Antarctica persists into the 21st century. [ABSTRACT FROM AUTHOR]

Lead is a priority pollutant, and lead metal is widely found in the environment as a waterproofing structural component in roofing, fence post covers, venting and flashing, as well as in industrial and urban waste. However, little is known of microbial interactions with metallic lead. The objective of this research was to investigate fungal roles in transformations of lead in a surface biofilm community growing on lead sheeting. The lead surface was found to support a diverse fungal community with several members, such as A ureobasidum pullulans, P homa macrostoma, P enicillium sp. and B otryotinia fuckeliana, probably originating from adjacent phylloplane communities. Many fungal isolates showed tolerance to lead compounds in growth inhibition assays and were able to mediate production of lead-containing secondary minerals in the presence of metallic lead. These exhibited widely differing morphologies to the lead-containing secondary minerals produced under abiotic conditions. The presence of pyromorphite ( Pb5( PO4) 3Cl) (approximately 50 wt%) was detected in the lead sheet biofilm, and we speculate that animal (bird) faeces could be a significant source of phosphorus in this location. Pyromorphite formation represents biomineralization of mobile lead species into a very stable form, and this research provides the first demonstration of its occurrence in the natural environment. [ABSTRACT FROM AUTHOR]

Highlights: [•] Early life exposure to Pb significantly altered the aminergic system in rat brain. [•] The alterations persisted in late life. [•] Developing rats at PND 45 were found to be more vulnerable to Pb than aged rats. [•] Nutrient mixture reversed Pb-induced perturbations in aminergic system and behavior. [•] Adequate intake of essential nutrients may be beneficial in reversing Pb-toxicity. [ABSTRACT FROM AUTHOR]

This research explores relationships between the spatial distribution of industrial facilities that release lead and lead compounds, community characteristics, and levels of violent and property crime in Hillsborough County, Florida. The spatial distribution of selected Toxics Release Inventory (TRI) facilities was modeled using Getis-Ord Gi* to classify census tracts into three groups: (1) tracts with statistically significant spatial clusters of TRIs; (2) tracts where there was a non-random-absence of TRIs; and (3) tracts with a random distribution of TRIs. Results of one-way ANOVA comparing demographics of clustered locations of TRIs to random and dispersed areas found significant differences, but local prediction models from geographically weighted regression (GWR) were no more useful in understanding TRI concentrations in areas where they are more clustered than in random or dispersed areas. GWR models predicting property crime were improved when TRI concentration was used in random and dispersed areas, but TRI concentration did not improve models predicting violent crime rates. [ABSTRACT FROM PUBLISHER]

Lead (Pb) is non-bioessential, persistent and hazardous heavy metal pollutant of environmental concern. Bioremediation has become a potential alternative to the existing technologies for the removal and/or recovery of toxic lead from waste waters before releasing it into natural water bodies for environmental safety. To our best knowledge, this is a first review presenting different mechanisms employed by lead resistant bacteria to resist high levels of lead and their applications in cost effective and eco-friendly ways of lead bioremediation and biomonitoring. Various lead resistant mechanisms employed by lead resistant bacteria includes efflux mechanism, extracellular sequestration, biosorption, precipitation, alteration in cell morphology, enhanced siderophore production and intracellular lead bioaccumulation. [Copyright &y& Elsevier]

Aim: The present investigation has been conducted to evaluate the hepatoprotective effect of Curcuma longa against lead induced toxicity. Materials and Methods: For this study, 24 Wistar albino rats were taken. Control group (n=8), group - I rats (n=8) were given lead acetate @ 1000 mg/kg bodyweight (BW) and group - II rats (n=8) were treated with Curcuma longa @ 500 mg/kg BW along with lead acetate @ 1000 mg/kg BW(daily orally for 28 days). Serum biomarkers, oxidative stress parameters and lead concentration in liver were estimated. Results: Oral administration of lead acetate for 28 days resulted in a significant increase in Aspartate amino transferase (AST), Alanine amino transferase (ALT), Alkaline phosphatase (ALP), significant increase of Lipid peroxidation (LPO) and decrease in Superoxide dismutase (SOD), Reduced glutathione (GSH) and increase in lead accumulation in liver. Treatment with Curcuma longa@ 500 mg/kg BWsignificantly (P< 0.01) decreased the elevated ALP, (p< 0.05) AST, ALT, LPO levels and increase in GSH levels and as compared to lead acetate treated group. But there was no significant difference in SOD level and lead concentration in liver when compared with lead acetate treated group. Conclusions: The study concludes that supplementation of Curcuma longa @ 500 mg/kg daily oral for 28 days has shown protection against lead inducedhepatotoxicity. [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: Lead exposure in children and occupationally exposed adults has been associated with reduced visuomotor and fine motor function. However, associations in environmentally exposed adults remain relatively unexplored. To address this, we examined the association between cumulative lead exposure—as measured by lead in bone—and performance on the grooved pegboard (GP) manual dexterity task, as well as on handwriting tasks using a novel assessment approach, among men in the VA Normative Aging Study (NAS). Methods: GP testing was done with 362 NAS participants, and handwriting assessment with 328, who also had tibia and patella lead measurements made with K-X-Ray Fluorescence (KXRF). GP scores were time (s) to complete the task with the dominant hand. The handwriting assessment approach assessed the production of signature and cursive lowercase l and m letter samples. Signature and lm task scores reflect consistency in repeated trials. We used linear regression to estimate associations and 95% confidence intervals (CI) with adjustment for age, smoking, education, income and computer experience. A backward elimination algorithm was used in the subset with both GP and handwriting assessment to identify variables predictive of each outcome. Results: The mean (SD) participant age was 69.1 (7.2) years; mean patella and tibia concentrations were 25.0 (20.7)μg/g and 19.2 (14.6)μg/g, respectively. In multivariable-adjusted analyses, GP performance was associated with tibia (β per 15μg/g bone=4.66, 95% CI: 1.73, 7.58, p =0.002) and patella (β per 20μg/g=3.93, 95% CI: 1.11, 6.76, p =0.006). In multivariable adjusted models of handwriting production, only the lm-pattern task showed a significant association with tibia (β per 15μg/g bone=1.27, 95% CI: 0.24, 2.29, p =0.015), such that lm pattern production was more stable with increasing lead exposure. GP and handwriting scores were differentially sensitive to education, smoking, computer experience, financial stability, income and alcohol consumption. Conclusions: Long-term cumulative environmental lead exposure was associated with deficits in GP performance, but not handwriting production. Higher lead appeared to be associated with greater consistency on the lm task. Lead sensitivity differences could suggest that lead affects neural processing speed rather than motor function per se, or could result from distinct brain areas involved in the execution of different motor tasks. [Copyright &y& Elsevier]

Avian wildlife species commonly ingest lead (Pb) spent shot or bullet fragments as grit or mistakenly as food. In previous studies in our laboratory and others, the toxicity varied based on the diet as well as type and quantity of Pb ingested. In the current study, domestic pigeons were gavaged with 1, 2, or 3 Pb pellets and then followed with weekly radiographs and blood physiologic endpoints for 28 days. Pellet retention decreased by roughly 50 % per week as pellets were either absorbed or excreted, except for week 4 where pellet number no longer was diminished. Size of retained pellets visually decreased over retention time. Birds dosed with a single #9 pellet showed mean blood Pb levels over 80 times higher than those of the controls, verifying Pb pellet absorption from the gut. A single Pb pellet also reduced plasma δ-aminolevulinic acid dehydratase (δ-ALAD) activity by over 80 % compared to controls, suggesting the potential for population injury in Pb pellet-exposed pigeons. [ABSTRACT FROM AUTHOR]

This article presents a review of data in literature that deals with childhood lead poisoning, sources of lead exposure for adults and children, and the U.S. Safe Drinking Water Act Lead and Copper Rule (LCR) of 1991. Lead is a corrosion-resistant, dense, ductile and malleable metal. The effects of lead exposure on children and adults are discussed. Historical trends in blood lead levels are included.

Heavy metal toxicity is a serious worldwide problem which adversely affects the growth, health, reproductive performance and life span of all living organisms. In my previous work1-4 I (Dhir) have worked on the toxicological aspects on the reproductive functions in female rats, physicochemical interactions in between the biomolecules with series of cations and also studied the importance of hydrophobic character of big biomolecules. Therefore; in this project I studied the importance of nature of anion in the salt of lead. Lead being a toxic cumulative poison and an environmental pollutant, experiments were conducted on an oral chronic dose (@35 mg/kg/day) for 90 days on adult female rats (Rattus Norvegicus) and its effect on the reproductive functions in relation to the biochemical effects were studied. It was observed that the chronic dose of various salts of lead caused an elevation in the level of proteins, acid phosphatase, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase in all the soft tissues which indicated tissue damage and the effects are received in the following order (as in case of anions): SO42- > NO3- > CH3COO- (in terms of toxicity) However no literature was available so far as to compare the effect of anion on the toxicity level of lead. The doubly charged sulphate anion (SOSO42-) interacts physicochemically with the various biological biomolecules (imidazole, cysteine sulfhydryls & amino group of lysine) results in tissue damage as in comparison with nitrate and acetate which are singly charged. Histological studies of ovary showed atresia (Figures 1-4) in all the stages of folliculogenesis sustaining the poor fertility observations. [ABSTRACT FROM AUTHOR]

The resultant effects of lead exposure are seen in almost all the systems of the body and results in toxicity to many organs. Since toxicity depends on its degree of uptake, distribution and metabolism, the authors investigated the differential uptake, accumulation and distribution of lead in organs of males and female Wistar rats following various routes of administration. Group 1 served as control male and control female; group 2 males and females received 5 mg/kg body weight of lead intraperitoneally for 8 days while group 3 males and female rats were administered drinking water containing 100 ppm of lead acetate for 18 days. Tissues were collected for analysis of the lead content using atomic absorption spectroscopy. The relative retention of lead by the tissues was greater in rats exposed to lead by the i.p. route varying in the order of accumulation / uptake in males as lungs > spleen > stomach > kidney > blood > heart and in females as spleen > stomach > heart > kidney > blood > lungs (i.p. route) and (oral route) as for males kidney > lungs > stomach > blood > heart > spleen, and females as kidney > lungs > stomach > blood > heart > spleen. Male Wistar rats showed more accumulation with oral exposure in lungs, spleen and blood with values for kidney and stomach being significantly (p < 0.05) higher when compared with females. Female Wistar rats showed more accumulation with i.p. exposure for spleen and stomach tissues while values for the heart was significantly (p < 0.05) higher than the males. Our findings suggest that lead retention and the organ distribution varied depending upon the sex and route of lead administration. [ABSTRACT FROM PUBLISHER]

The increasing use of lead (Pb) for industrial purposes has resulted in the significant increase in environmental contamination of our planet especially in concern to water and food. In this study using the electron scanning microscopy (SEM), the authors showed the effects of this metal as a result of a chronic and cumulative process. As a primary method of detection of Pb in situ, SEM was chosen, coupled with a detection system Noran Voyager of basic microanalysis X-ray (SEM-XRM), with detection system energy dispersive spectrometry. Mice BALB/c was used as a study model. An animal model of inflammation was used, that consisted in the formation of a subcutaneous pocket of air. It was observed that 75% of Pb stock was captured by the liver, the main target organ in the capture of the metal, the kidney was the second organ to capture the Pb stock and the third was the spleen. It was verified that a low deposition of Pb was found in the lungs and the brain. The main results of this study showed how Pb is captured by different organs. We also demonstrated the vulnerability to inflammation of this metal. [ABSTRACT FROM PUBLISHER]

Abstract: Lead (Pb2+) exposure continues to be an important concern for fish populations. Research is required to assess the long-term behavioral effects of low-level concentrations of Pb2+ and the physiological mechanisms that control those behaviors. Newly fertilized zebrafish embryos (<2h post fertilization; hpf) were exposed to one of three concentrations of lead (as PbCl2): 0, 10, or 30nM until 24hpf. (1) Response to a mechanosensory stimulus: Individual larvae (168hpf) were tested for response to a directional, mechanical stimulus. The tap frequency was adjusted to either 1 or 4taps/s. Startle response was recorded at 1000fps. Larvae responded in a concentration-dependent pattern for latency to reaction, maximum turn velocity, time to reach V max and escape time. With increasing exposure concentrations, a larger number of larvae failed to respond to even the initial tap and, for those that did respond, ceased responding earlier than control larvae. These differences were more pronounced at a frequency of 4taps/s. (2) Response to a visual stimulus: Fish, exposed as embryos (2–24hpf) to Pb2+ (0–10μM) were tested as adults under low light conditions (∼60μW/m2) for visual responses to a rotating black bar. Visual responses were significantly degraded at Pb2+ concentrations of 30nM. These data suggest that zebrafish are viable models for short- and long-term sensorimotor deficits induced by acute, low-level developmental Pb2+ exposures. [Copyright &y& Elsevier]

Waterbird feces (mainly mallard Anas platyrhynchos and coot Fulica atra) were collected from four wetlands in Southern Spain in the field or during capture (n = 558 and n = 59, respectively) to study lead (Pb) shot ingestion. Lead and aluminum (Al) concentrations along with Pb isotope signatures were used to identify sources of Pb exposure. The profile and concentrations of porphyrins and biliverdin in feces were used as biomarkers of toxicological effects. Feces with Pb concentrations ≥34 μg/g d.w. showed higher Pb/Al ratios, together with lower 206Pb/207Pb and 208Pb/207Pb ratios, and higher 208Pb/206Pb ratios, than feces with <34 μg/g d.w. Isotope signatures and Pb/Al ratios together indicated that Pb shot ingestion was the likely cause of the high Pb levels in some samples, whereas sediment ingestion was linked to lower/background levels. Coproporphyrin I and protoporphyrin IX were also higher in feces with Pb ≥34 μg/g d.w., indicating measurable disruption in heme synthesis. Noninvasive fecal sampling permits study of the degree and source of Pb exposure and physiological effects, with low-effort and minimal disturbance to waterbirds. [ABSTRACT FROM AUTHOR]

Abstract: While the toxic effects of lead have been recognized for millennia, it has remained a significant public health concern due to its continued use and toxicological potential. Of particular interest is the increased susceptibility of young children to the toxic effects of lead. Although the exact mechanism(s) for lead toxicity is currently not well understood, research has established that it can be a potent NMDA antagonist. Previous research has established that exposure to NMDA antagonists during the brain growth spurt period (first 2weeks of life in mice) can produce apoptotic neurodegeneration throughout the brain. Based on this information, the ability of lead exposure (two injections of 350mg/kg lead 4h apart) to produce apoptosis in the neonatal mouse brain was assessed histologically 8–24h after treatment using activated caspase-3 immunohistochemistry, De Olmos silver technique, Nissl staining, and electron microscopy. Lead exposure produced significant neurodegeneration in the caudate/putamen, hippocampus, subiculum, and superficial and deep cortical layers of the frontal cortical regions. Further ultrastructural examination revealed cellular profiles consistent with apoptotic cell death. Statistical results showed that lead exposure significantly increased apoptotic neurodegeneration above that seen in normal controls in animals treated at postnatal day 7, but not on day 14. The results of this study may provide a basis for further elucidation of mechanisms through which the immature nervous system may be particularly susceptible to lead exposure. [Copyright &y& Elsevier]

For better understanding the metabolic adaptations to Pb stress in submerged plants, the alterations in mineral elements uptake and in secondary metabolism were studied in leaves of Vallisneria natans (Lour.) Hara exposed to 0–100μM Pb for 0–7d. Pb content increased in leaves in a dose-dependent way. The increase of calcium, magnesium and iron content and the decrease of phosphorus, potassium and manganese content were detected in leaves of V. natans under Pb stress, while no significant changes were detected in copper and zinc concentration. Meanwhile, there was an increase in the concentrations of total phenolic and flavonoids. Pb treatment caused an increase in the catalytic activities of shikimate dehydrogenase, phenylalanine ammonialyase and polyphenol oxidase. The results suggest that nutrient uptake and secondary metabolism were actively regulated by V. natans plants in response to Pb stress. [Copyright &y& Elsevier]

The objective of this study was to determine the blood lead level (BLL) of children aged under 5 living in western Uttar Pradesh, India. A total of 100 blood samples, 100 drinking water samples, and 21 vegetable samples were assessed for lead (Pb) contamination. BLL was observed in the range of 3-11.58 µg dL-1 with a maximal level of 11.58 ± 0.05 µg dL-1 in Kazipur village. Lead in water samples was detected in the range of 0.006-0.095 ppm and identified at upto 9.5-fold higher than the stated permissible limit. A significant positive correlation (+0.679) was obtained between BLL and water Pb levels. All vegetable samples were also contaminated with Pb upto 12-fold higher than the permissible limit of 2.5 µg g-1 of Prevention of Food Adulteration Act (PFA) 1954. Untreated industrial effluents were identified as the responsible factors for Pb occurrence in the study area. The presence of lead may be associated with the increased antisocial activities of children living in western Uttar Pradesh. Children with elevated BLL had poorer nutritional status than those with background Pb levels. There is an urgent need for a national campaign to monitor the BLL of children in India. [ABSTRACT FROM AUTHOR]

Abstract: Pregnant women are particularly susceptible to toxic effects associated with lead (Pb) exposure. Pb accumulates in bone tissue and is rapidly mobilized from bones during pregnancy, thus resulting in fetal contamination. While vitamin D receptor (VDR) polymorphisms modify bone mineralization and affect Pb biomarkers including blood (Pb-B) and serum (Pb-S) Pb concentrations, and %Pb-S/Pb-B ratio, the effects of these polymorphisms on Pb levels in pregnant women are unknown. This study aimed at examining the effects of three (FokI, BsmI and ApaI) VDR polymorphisms (and VDR haplotypes) on Pb levels in pregnant women. Pb-B and Pb-S were determined by inductively coupled plasma mass spectrometry in samples from 256 healthy pregnant women and their respective umbilical cords. Genotypes for the VDR polymorphisms were determined by PCR and restriction fragment length digestion. While the three VDR polymorphisms had no significant effects on Pb-B, Pb-S or %Pb-S/Pb-B ratio, the haplotype combining the f, a, and b alleles for the FokI, ApaI and BsmI polymorphisms, respectively, was associated with significantly lower Pb-S and %Pb-S/Pb-B (P <0.05). However, maternal VDR haplotypes had no effects on Pb levels in the umbilical cords. To our knowledge, this is the first study showing that a combination of genetic polymorphisms (haplotype) commonly found in the VDR gene affects Pb-S and %Pb-S/Pb-B ratios in pregnant women. These findings may have major implications for Pb toxicity because they may help to predict the existence of a group of subjects that is genetically less prone to Pb toxicity during pregnancy. [ABSTRACT FROM AUTHOR]

Background Lead is a known toxicant that occurs naturally in the environment. Bisphenol A (BPA) is an industrial chemical used primarily in polycarbonate plastic and epoxy resins. It has been 30 years since lead exposure was measured at a national level, and it is the first time for a national assessment of BPA exposure. Data and methods Data are from the 2007-2009 Canadian Health Measure Survey. Lead in whole blood (PbB) and urinary BPA were measured in 5,319 and 5,476 respondents aged 6 to 79, respectively. Geometric means (GMs) are presented by age group and sex for PbB (µg/dL), volume-based BPA (µg/L), and creatinine-standardized BPA (µg/g creatinine). Adjusted least squares geometric means (LSGMs) for PbB and BPA are presented by selected covariates. Results PbB was detected in 100% of the population, with a GM concentration of 1.34 µg/dL. Adults aged 60 to 79 and males had significantly higher GM PbB concentrations. Lower household income, being born outside Canada, living in a dwelling at least 50 years old, current or former smoking, and drinking alcohol at least once a week were associated with higher PbB concentrations. Urinary BPA was detected in 91% of the population, with a GM concentration of 1.16 µg/L (1.40 µg/g creatinine). Children aged 6 to 11 had significantly higher GM creatinine-standardized BPA concentrations than did other age groups. Interpretation Although PbB concentrations have declined dramatically since the 1970s, socio-demographic characteristics, the age of dwellings, and certain lifestyle behaviours are associated with higher levels. Given the short half-life of orally ingested BPA and the high frequency of detection, the CHMS data suggest continual widespread exposure in the Canadian population. [ABSTRACT FROM AUTHOR]

Background. One of the principle symptoms of lead poisoning is the development of neurological disorders. Neuronal response is closely related to DNA methylation changes. Aim. In this study, we estimated p16 methylation in nine individuals exposed to lead using methylation-specific polymerase chain reaction followed by analysis of the methylated cytosine content of the product by thermal denaturation. Results. We found that, based on lead blood concentration, lead-exposed individuals were divided into two groups. Among highly exposed individuals (blood Pb2+ concentration = 51–100 μg/dL), we observed complete CpG methylation, whereas for low Pb2+ concentrations (blood Pb2+ concentration = 6–11 μg/dL), we observed partial methylation. Conclusion. Our results show that among lead-overexposed individuals, p16 methylation is frequent and extensive, and suggest that DNA methylation could be involved in the mechanism by which lead induces neurotoxicity. [ABSTRACT FROM AUTHOR]

Objectives. Laboratories that test New York State (NYS) employees and adult residents for lead exposure are required to report blood lead test results to the NYS Department of Health's Heavy Metals Registry. This registry is used tc monitor exposures and to identify new high-risk occupational and nonoccupational activities. Methods. We used interviews conducted with people having blood lead eve of ⩾25 micrograms/deciliter (pg/dL) reported to the Heavy Metals Registry to determine the primary source of lead exposure. We reviewed this information together with demographic information, for the years 1994 through 2006. Results. While overall there has been an increase in the number of tests bein conducted on NYS residents since 1994, the vast majority of the increase is among those with the lowest blood lead levels (<10 pg/dL). Conversely, therE has been a decline in the number of adults tested with blood lead levels of ⩾25 pg/dL in NYS due primarily to occupational exposures. However, nonocc pational exposures do represent a relatively large percentage of the individua with severely elevated blood lead levels (⩾60 pg/dL). Conclusions. Although a surveillance system based on blood lead levels cannot identify the true magnitude of adult lead poisoning, the NYS Heavy Meta Registry has proven to be an important tool for identifying situations in which adult lead poisoning is occurring, and assists in guiding lead poisoning preve tion among adults. [ABSTRACT FROM AUTHOR]

Abstract: Object: Indoor shooting is a popular recreational activity all over the world. It is also a known source of exposure to lead fumes and dusts for the general, i.e. the non-occupationally exposed population. This study aimed at reporting the lead levels in blood of indoor shooters in Germany in association with personal behaviour at shooting ranges. Methods: Seven marksmen were examined via self-administered questionnaires. Lead level in blood (BLL) as well as airborne lead concentration (personal air sampling (PAS)) were detected. Results: All measured blood lead levels (median: 290μglead/L; range: 240–450μglead/L) exceeded the values of the German general population (50μg/L). Shooters sweeping the range after training seemed especially exposed (PAS: 7.14mglead/m3). Conclusion: While extensive public effort is undertaken to prevent the general population from environmental lead exposure this short report gives reason to keep recreational shooting in mind when facing elevated blood lead levels or clinical symptoms possibly associated with lead intoxication. [Copyright &y& Elsevier]

Abstract: Prolonged exposure to inorganic lead (Pb2+) during development has been shown to influence activity-dependent synaptic plasticity in the mammalian brain, possibly by altering the regulation of intracellular Ca2+ concentration ([Ca2+]i). To explore this possibility, we studied the effect of Pb2+ exposure on [Ca2+]i regulation and synaptic facilitation at the neuromuscular junction of larval Drosophila. Wild-type Drosophila (CS) were raised from egg stages through the third larval instar in media containing either 0μM, 100μM or 250μM Pb2+ and identified motor terminals were examined in late third-instar larvae. To compare resting [Ca2+]i and the changes in [Ca2+]i produced by impulse activity, the motor terminals were loaded with a Ca2+ indicator, either Oregon Green 488 BAPTA-1 (OGB-1) or fura-2 conjugated to a dextran. We found that rearing in Pb2+ did not significantly change the resting [Ca2+]i nor the Ca2+ transient produced in synaptic boutons by single action potentials (APs); however, the Ca2+ transients produced by 10Hz and 20Hz AP trains were larger in Pb2+-exposed boutons and decayed more slowly. For larvae raised in 250μM Pb2+, the increase in [Ca2+]i during an AP train (20Hz) was 29% greater than in control larvae and the [Ca2+]i decay τ was 69% greater. These differences appear to result from reduced activity of the plasma membrane Ca2+ ATPase (PMCA), which extrudes Ca2+ from these synaptic terminals. These findings are consistent with studies in mammals showing a Pb2+-dependent reduction in PMCA activity. We also observed a Pb2+-dependent enhancement of synaptic facilitation at these larval neuromuscular synapses. Facilitation of EPSP amplitude during AP trains (20Hz) was 55% greater in Pb2+-reared larvae than in controls. These results showed that Pb2+ exposure produced changes in the regulation of [Ca2+]i during impulse activity, which could affect various aspects of nervous system development. At the mature synapse, this altered [Ca2+]i regulation produced changes in synaptic facilitation that are likely to influence the function of neural networks. [Copyright &y& Elsevier]

We studied the effects of elevated heavy metal uptake on the sperm quality and the antioxidant mechanisms of sperm and testis of red deer from a Pb mining area in Spain. Testis, liver and bone of red deer from mining (n = 21) and control (n = 20) areas were obtained from hunters and analyzed for Pb, Zn, Cu, Cd, As and Se. Testes were weighed and measured. Motility, acrosome integrity and viability and functionality of membrane were evaluated in epididymal spermatozoa. Lipid peroxidation, total glutathione, glutathione peroxidase (GPX) and superoxide dismutase (SOD) were studied in testis and spermatozoa. Deer from mined areas showed less Cu in testis, a higher testis mass and size and reduced spermatozoa membrane viability and acrosome integrity. Effects on sperm quality were associated to decreased Cu and increased Se in testis, and to decreases in the activity of SOD and GPX in testis and spermatozoa. [Copyright &y& Elsevier]