Environmental and occupational exposure to lead as a potential risk factor for cardiovascular disease

Prenatal exposure to essential metals and blood pressure at preschool age: A birth cohort study

AIMS

To investigate the association between prenatal exposure to essential metals and the offspring blood pressure (BP) at preschool age.

MATERIALS AND METHODS

Data from a birth cohort study including 1113 mother-child pairs were analyzed. The associations between individual prenatal essential elements and offspring BP were analyzed using generalized linear regression models. Bayesian Kernel Machine Regression (BKMR) and weighted quantile sum regression (WQS), were employed to examine the combined effects of prenatal metal exposures on offspring BP. The associations between essential metals and high blood pressure (HBP) of offspring were appraised using logistic regression model.

RESULTS

In the single-metal models, we found that maternal magnesium (Mg) concentrations were negatively associated with the offspring BP. The results of BKMR and WQS also identified a negative association between maternal essential metals mixtures and offspring BP. Logistic regression showed that compared to the highest quartiles of maternal Mg, the odds ratio (OR) for HBP in the lowest quartiles was 4.27 (95 % CI: 1.84-9.93). No significant associations were observed for other essential metals (all P value > 0.05). Additionally, no significant association was found between umbilical cord blood metal concentrations and offspring BP.

CONCLUSIONS

Maternal essential metals mixtures, rather than those in umbilical cord blood, were negatively associated with offspring BP. Besides, lower maternal Mg levels were linked to a higher prevalence of HBP in offspring. Our findings provide significant evidence for exploring the effects of maternal essential metal elements on offspring BP.

Disease burden of ischemic heart disease attributable to lead exposure in China from 1990 to 2019, and projections until 2030

The burden of ischemic heart disease (IHD) attributable to lead exposure in China remains poorly understood. Using data from the Global Burden of Disease 2019, we aim to explore the epidemiological trends and specific burdens, providing insights into environmental health. In 2019, the number of deaths and disability-adjusted life years of IHD attributable to lead exposure in China reached 105,857 and 1,899,139, respectively. The age-standardized mortality rate (ASMR) and age-standardized DALY rate (ASDR) were 6.46 and 101.29 per 100,000 population, respectively. The burden was higher in males than in females. The estimated ASMR is projected to decrease to 7.08 and 3.37 per 100,000 for males and females by 2030, while the ASDR is expected to decline to 100.57 and 45.30 per 100,000 for males and females. The burden of IHD attributable to lead exposure is substantial in China, highlighting the grave public health concern posed by lead pollution.

Assessing Heavy Metal Contamination in Commonly Used Fertilizers for Polyculture Fish Ponds and Its Implications for Human Health: A Comprehensive Investigation

Over-fertilizing fish ponds can cause pollution, introducing heavy metals into the food chain and posing health risks. The present study investigated the incidence of heavy metals (Pb, Cu, Cd, and Cr) in commonly applied fertilizers, including nitrogen, phosphorus and potassium (NPK), triple superphosphate (TSP), and di-ammonium phosphate (DAP), and their association with heavy metals in water, sediment, and cultured fish species (Catla catla, Labeo rohita, and Cyprinus carpio) in polyculture fish ponds. The study was conducted over 4 months, with four groups in triplicates: control (no fertilizer), group 1 (NPK), group 2 (TSP), and group 3 (DAP). Heavy metal analysis was carried out using atomic absorption spectrophotometry before and after fertilizer application. Significantly (p < 0.05) higher levels of heavy metals were observed in water and sediment after applying fertilizers, with the most pronounced results in group 3 (DAP) followed by group 2 (TSP). The concentration of heavy metals was significantly (p < 0.05) higher in group 3 (DAP) fertilizers compared to other groups. Compared to the control, the concentration and bioaccumulation of heavy metals were significantly (p < 0.05) higher in the fertilizer-applied groups, with notably higher levels in group 3 (DAP). Cluster analysis and the correlation matrix did not show any significant association between the heavy metals and the fertilizers, indicating a complex interplay between the biotic and abiotic factors of the system. The health index (HI) value was < 1 in fish muscles of all studied groups, indicating the fish are safe for consumption. The study recommends monitoring and regulating fertilizer use, especially DAP, to prevent heavy metal contamination, and exploring sustainable alternatives to minimize environmental and health risks.

Chronic lead exposure and burden of cardiovascular disease during 1990-2019: a systematic analysis of the global burden of disease study

Background

Cardiovascular diseases (CVD) are the leading causes of death and disability worldwide. Lead exposure is an important risk factor for CVD. In our study, we aimed to estimate spatial and temporal trends in the burden of cardiovascular disease associated with chronic lead exposure.

Methods

The data collected for our study were obtained from Global Burden of Disease (GBD) study 2019 and analyzed by age, sex, cause, and location. To assess the temporal trends in burden of CVD attributable to chronic lead exposure over 30 years, we used Joinpoint regression analysis.

Results

In 2019, the number of lead exposure-attributable CVD deaths and disability-adjusted life-years (DALYs) were 0.85 and 17.73 million, 1.7 and 1.4 times more than those observed in 1990, respectively. However, the corresponding age-standardized rates (ASR) of death and DALY gradually decreased from 1990 to 2019, especially from 2013 to 2019. Over the last 30 years, among 21 GBD regions and 204 countries and territories, the High-income Asia Pacific and the Republic of Korea experienced the largest reductions in age-standardized DALY and death rates, while Central Asia and Afghanistan experienced the largest increases. Males and the elderly population suffered higher death rates and DALY burdens than females and the young population. Furthermore, we observed that higher socio-demographic index (SDI) regions demonstrated lower ASR of death and DALY rates. In 2019, the low and low-middle SDI regions, especially South Asia, exhibited the highest burden of CVD attributable to lead exposure.

Conclusion

Our study provides a thorough understanding of the burden of CVD attributable to chronic lead exposure. The findings confirm the significance of implementing lead mitigation strategies and increasing investment in CVD prevention and treatment. These measures are crucial in reducing the burden of CVD and promoting public health on a global scale.

Lead activates neutrophil degranulation to induce early myocardial injury in mice

Lead (Pb) is a pervasive toxic metal contaminant associated with a high risk of myocardial injury. However, the precise mechanism underlying Pb-induced myocardial injury has yet to be fully elucidated. In this study, a murine model of Pb exposure (0, 1, 5, and 10 mg/kg) was employed to investigate the involvement of neutrophil degranulation in the induction of myocardial injury. Notably, serum levels of cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) increased significantly in Pb-exposed mice, whereas cTnI levels in cardiomyocytes decreased, suggesting that Pb exposure may cause early myocardial injury. Moreover, Pb exposure was found to promote neutrophil degranulation, as evidenced by elevated myeloperoxidase (MPO) and neutrophil elastase (NE) concentrations in both the serum of Pb-exposed workers and Pb-exposed mice, as well as the extracellular supernatant of neutrophils following exposure. However, we found that serum level of cTnI enhanced by Pb exposure is associated with increased NE levels in the serum, but not with MPO levels. Upon treatment with NE inhibitor (sivelestat), the serum level of cTnI markedly reduced in Pb-exposed mice, we found that early myocardial injury is associated with NE levels in the serum. At the molecular level, western blotting analysis revealed an upregulation of ERK1/2 expression in vitro following Pb exposure, suggesting that the activation of the ERK1/2 signaling pathway may underlie the participation of neutrophil degranulation in Pb-induced myocardial injury. In summary, our findings demonstrate that Pb exposure can initiate early myocardial injury by promoting the neutrophil degranulation process, thereby highlighting the potential role of this process in the pathogenesis of Pb-associated myocardial injury.

Exposure to Heavy Metals and Serum Adiponectin Levels among Workers: A 2-Year Follow-Up Study

The workers exposed to metal fumes had an increased risk of metabolic syndrome, which was correlated with decreased serum adiponectin. Thus, we aimed to explore whether heavy metal exposure affects the adiponectin level. There were 96 male workers recruited from a shipyard at baseline. Apart from 82 participants completed the follow-up assessments, new participants were recruited in next year. Finally, there were 100 welding workers in the exposure group and 31 office workers in the control group. Inferential statistics on repeated measures were performed using generalized estimating equations. A weighted quantile sum (WQS) regression model was conducted to examine the joint effect of the multimetal exposure with serum adiponectin. Significantly negative associations of metals with adiponectin were detected in the welding workers, including Cr (β = -0.088; 95% CI: -0.148, -0.027), Mn (β = -0.174; 95% CI: -0.267, -0.081), Co (β = -0.094; 95% CI: -0.158, -0.029), Ni (β = -0.108; 95% CI: -0.208, -0.008), Cd (β = -0.067; 95% CI: -0.115, -0.018), and Pb (β = -0.089; 95% CI: -0.163, -0.015). The WQS regression suggested that Pb was the greatest contributor. In conclusion, our findings highlighted that welding workers exposed to heavy metals would reduce serum adiponectin.

Lead suppresses perlecan expression via EGFR-ERK1/2-COX-2-PGI2 pathway in cultured bovine vascular endothelial cells

Vascular endothelial cell growth is essential for the repair of intimal injury. Perlecan, a large heparan sulfate proteoglycan, intensifies fibroblast growth factor-2 (FGF-2) signaling as a co-receptor for FGF-2 and its receptor, and promotes the proliferation of vascular endothelial cells. Previously, we reported that 2 µM of lead, a toxic heavy metal, downregulated perlecan core protein expression and then suppressed the growth of vascular endothelial cells. However, since the mechanisms involved in the repression of perlecan by lead remains unclear, we analyzed its detailed signaling pathway using cultured bovine aortic endothelial cells. Our findings indicate that 2 µM of lead inhibited protein tyrosine phosphatase (PTP) activity and induced cyclooxygenase-2 (COX-2) via phosphorylation of the epidermal growth factor receptor (EGFR) and its downstream extracellular signal-regulated kinases (ERK1/2). In addition, among the prostanoids regulated by COX-2, prostaglandin I2 (PGI2) specifically contributes to the downregulation of perlecan expression by lead. This study revealed an intracellular pathway-the EGFR-ERK1/2-COX-2-PGI2 pathway activated by inhibition of PTP by lead-as a pathway that downregulates endothelial perlecan synthesis. The pathway is suggested to serve as a mechanism for the repression of perlecan expression, which leads to a delay in cell proliferation by lead.

Evaluation of eventual toxicities of treated textile wastewater using anoxic-aerobic algal-bacterial photobioreactor

Water pollution is one of the major challenges and is of serious concern in the world. Toxicities generated by industrial activities severely deteriorate aquatic and terrestrial ecosystems during their uncontrolled discharge and accentuate water scarcity problems. An adequate treatment of released effluents seems to be mandatory. This study investigated the effect of synthetic textile wastewater (STWW) before and after an innovative algal-bacterial treatment occurred under anoxic-aerobic conditions on growth and mineral contents of radish plants. The health risk assessment was performed after the consumption of irrigated plants by rats. Results revealed a significant reduction in heavy metals content in plants irrigated with treated STWW, and rats fed with these plants showed normal health status. Rats fed with plants irrigated with raw STWW showed a disturbance of their homeostasis. The innovative treatment using algal-bacteria under anoxic-aerobic conditions succeeds to reduce the toxicity of raw STWW and provide an alternative water resource able to tackle water shortage.

Effects of Long-Term Lead Exposure on Antioxidant Enzyme Defense System in Organs of Brown Hare (Lepus europaeus Pallas) as a Bioindicator of Environmental Pollution in Croatia

In Croatia, Podravina is a well-known lead-polluted region due to the intensive exploitation of natural gas, a highly developed agricultural industry, and a traffic hub with several heavily traveled roads. It represents a natural environment with a great variety of wildlife, especially hares (Lepus europaeus Pallas), which may serve as an indicator for environmental quality assessment. This study was conducted to estimate the bioaccumulation of lead in hare liver, kidney, muscle, and brain during long-term exposure and its impact on the oxidative status of the organism and to investigate a possible lead exchange ionic mechanism in the brain. In the organs of two hare groups (experimental from polluted area and control from the island of Krk), Ca, Fe, Mg, Na, lead concentrations, and antioxidant enzyme defense system were analyzed. The accumulation of lead was highest in the brain (3.7-fold higher compared to the control group) and lowest in the liver (1.6-fold higher compared to the control group). Kendall-Tau and multiple regression analysis showed that the increased lead content caused a stronger exchange of Ca and Na ions in the brain. We proposed that lead either mobilizes intracellular cation stores or causes competitive displacement of Ca from the binding site in intoxicated cells. A linear predictive model for cell intoxication by lead was proposed, where GPx and SOD were predominantly influenced by long-term lead exposure. The presented results showed that long-term lead exposure in hares negatively affected their oxidative status and caused the strongest toxicity in the brain and muscles, making their survival and/or population vulnerable.

Exploring the Link Between the Serum/Blood Levels of Heavy Metals (Pb, As, Cd, and Cu) and 2 Novel Biomarkers of Cardiovascular Stress (Growth Differentiation Factor 15 and Soluble Suppression of Tumorigenicity 2) in Copper Smelter Workers

OBJECTIVE

Studying the association between the occupational exposure to Pb, As, Cd, and Cu with the serum levels of 2 novel biomarkers of cardiovascular stress; growth differentiation factor 15 and soluble suppression of tumorigenicity 2, in some Egyptian Cu smelter workers.

METHODS

Forty-one exposed workers and 41 administrative controls were clinically evaluated. Serum/blood levels of heavy metals and biomarkers were measured for both groups.

RESULTS

The smelter workers showed significantly elevated levels of heavy metals and biomarkers compared with controls. The elevated serum levels of both biomarkers were significantly and positively correlated with each other, the levels of heavy metals, and the duration of employment of the exposed workers.

CONCLUSIONS

There was a significant association between the levels of heavy metals and both biomarkers among the smelter workers. Further prospective studies should be performed.

Early Life Short-Term Exposure to Polychlorinated Biphenyl 126 in Mice Leads to Metabolic Dysfunction and Microbiota Changes in Adulthood

Early life exposure to environmental pollutants may have long-term consequences and harmful impacts on health later in life. Here, we investigated the short- and long-term impact of early life 3,3',4,4',5-pentacholorobiphenyl (PCB 126) exposure (24 μg/kg body weight for five days) in mice on the host and gut microbiota using 16S rRNA gene sequencing, metagenomics, and 1H NMR- and mass spectrometry-based metabolomics. Induction of Cyp1a1, an aryl hydrocarbon receptor (AHR)-responsive gene, was observed at 6 days and 13 weeks after PCB 126 exposure consistent with the long half-life of PCB 126. Early life, Short-Term PCB 126 exposure resulted in metabolic abnormalities in adulthood including changes in liver amino acid and nucleotide metabolism as well as bile acid metabolism and increased hepatic lipogenesis. Interestingly, early life PCB 126 exposure had a greater impact on bacteria in adulthood at the community structure, metabolic, and functional levels. This study provides evidence for an association between early life environmental pollutant exposure and increased risk of metabolic disorders later in life and suggests the microbiome is a key target of environmental chemical exposure.

Association between Heavy Metal Exposure and Dyslipidemia among Korean Adults: From the Korean National Environmental Health Survey, 2015-2017

Cardiovascular disease (CVD) is a leading cause of death in Korea. Dyslipidemia, characterized by the presence of abnormal lipid levels, has been suggested as an early diagnostic and preventable factor for CVD. Recent studies have shown that exposure to lead (Pb), cadmium (Cd), and mercury (Hg) affects lipid metabolism. This study aimed to verify the association between heavy metal concentrations and serum lipid profiles in the general population. A representative sample of 2591 Korean adults from the Korean National Environmental Health Survey (2015−2017) was analyzed. The associations between heavy metals [Blood Pb (BPb), blood Hg (BHg), urinary Hg (UHg), urinary Cd (UCd)] and serum lipid profiles [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), non-low level of high-density lipoprotein cholesterol (Non-HDL-C)] were assessed using regression analysis. After adjusting for demographic and socioeconomic factors, the proportional changes in serum lipid levels were significantly associated with increases in BPb, BHg, and UHg levels (p for trend < 0.05). Overall, BPb, BHg, and Uhg levels positively correlated with dyslipidemia, whereas UCd levels did not show a significant association. Our results suggest that heavy metal exposure, at low levels, may contribute to an increased prevalence of dyslipidemia in Korean adults.

Association Between Blood Lead Levels and Hypertension in a South Indian Population: A Case-Control Study

Background

Exposure to lead and its accumulation in the body can lead to progressive adverse effects, including increased blood pressure which is associated with the onset of cardiovascular diseases. In this study, we aimed to determine the relationship between blood lead levels and blood pressure. In addition, we compared blood lead levels between hypertensives and normotensives to determine relationships, if any, between lead exposure and high blood pressure.

Methodology

This was a hospital-based, case-control study. In total, 102 individuals (hypertensives = 51, normotensives = 51) were included in this study. Hypertensive patients (defined as systolic blood pressure (SBP) of ≥140 mmHg, diastolic blood pressure (DBP) of ≥90 mmHg, or taking antihypertensive medication for regulating blood pressure) were considered to be study cases and normotensive individuals were considered to be study controls. Blood lead levels were compared between the two groups, and the effects of blood lead levels on SBP and DBP were estimated. The blood lead levels were measured using optical emission spectrometry.

Results

The mean blood lead level among hypertensive individuals (5.5743 ± 1.77 µg/dL) was significantly higher compared to normotensive individuals (4.5029 ± 1.3213 µg/dL, P = 0.001). A positive correlation was detected between blood lead levels and SBP (r = 0.304, P = 0.002). However, no significant correlation was found between blood lead levels and DBP.

Conclusions

Blood lead levels were significantly higher in hypertensive patients compared to normotensive individuals. A significant positive correlation was observed between blood lead levels and SBP.

Single Nucleotide Polymorphism of TWIST2 May Be a Modifier for the Association between High-Density Lipoprotein Cholesterol and Blood Lead (Pb) Level

The association between lead (Pb) exposure and lower high-density lipoprotein cholesterol (HDL-C) was reported; however, the mechanism was unclear. Our purpose was to investigate the association of Pb, lipid profile, and to study the associated SNPs using a genome-wide association study (GWAS). A total of 511 participants were recruited to check blood Pb levels, lipid profile, and genotypes with Taiwan Biobank version 2.0 (TWB2). Our main result shows that HDL-C was significantly negatively associated with blood Pb levels, adjusted for gender, body mass index (BMI), and potential confounders. In addition, via the TWB2 GWAS, only two SNPs were found, including rs150813626 (single-nucleotide variation in the TWIST2 gene on chromosome 2), and rs1983079 (unclear SNP on chromosome 3). Compared to the rs150813626 GG carriers, the AA and AG carriers were significantly and negatively associated with HDL-C. We analyzed the interaction of rs150813626 SNP and blood Pb, and the HDL-C was consistently and negatively associated with blood Pb, male, BMI, and the rs150813626 AA and AG carriers. Moreover, the rs150813626 AA and blood Pb interaction was significantly and positively associated with HDL-C. In conclusion, the SNPs rs150813626 and rs1983079 were significantly associated with HDL-C in Pb-exposed workers. Furthermore, the interaction of rs150813626 AA and blood Pb had a positive influence on HDL-C. TWIST may inhibit osteoblast maturation, which might relate to bone Pb deposition and calcium metabolism. The mechanism needs more investigation in the future.

Gold nanostar as an ultrasensitive colorimetric probe for picomolar detection of lead ion

The sensitivity for analytes of interest is vital for environment protection and food safety. Here, we propose an extremely sensitive assay toward Pb²⁺ by using gold nanostars (GNSs) as probes based on the catalytic activity of Pb on etching gold atoms after being reduced in the presence of 2-mercaptoethanol (2-ME) and sodium thiosulfate. GNSs were prepared by using 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid as both the reducing and capping agents, enabling high stability and sensitivity for quantitation of Pb²⁺. Upon increasing Pb²⁺ concentration over the range of 0-10 μM, GNS solution color changed from greenish-blue to blue to purple to red, and eventually to colorless. The color change can be distinguished by naked eye at the Pb²⁺ concentration as low as 200 pM. Through monitoring longitudinal localized surface plasmon of GNSs, Pb²⁺ could be detected with a limit of detection of 1.5 pM, and the working range is 2 pM-1 μM. The ultra-high sensitivity of our assay stems from the high catalysis of Pb on etching gold on tips and branches in the presence of 2-ME and sodium thiosulfate, leading to the shape deformation to spherical gold nanoparticle and the corresponding significant changes in their optical properties. The assay provides high selectivity of Pb²⁺ over the tested interfering metal ions like Cu²⁺. With high sensitivity and selectivity, the assay was efficiently validated by analyzing water samples and monitoring the migration of Pb²⁺ from the tested container to water.

Blood lead and mercury levels are associated with low resting heart rate in community adolescent boys

While the neurotoxic effects of heavy metals at even low levels have been well-studied, few studies have examined the cardiovascular effects of heavy metals on resting heart rate and these have focused on adult populations. The present study aimed to examine the association between low-level environmental lead and mercury exposure and resting heart rate in community adolescents. As part of the China Jintan Cohort Study, 532 adolescents aged 12 years (SD = 0.6) were tested for blood levels of lead (BLL) and mercury (BML) and resting heart rate (RHR). Generalized linear models were conducted to test the relationship between BLL and BML and RHR, controlling for children's sex, age, and socioeconomic status. Analyses were clustered at the preschool level when the children were recruited to adjust for standard error. The mean (SD) BLL and BML were 3.14 (SD = 1.19) μg/dL and 1.26 (SD = 0.68) μg/L at age 12 years, respectively. After adjusting for confounders, we found a significant interaction between BML and BLL in predicting RHR in boys (B = -1.27, SE = 0.49, p < 0.01, n = 289). We created BLL and BML groups in boys based on median cut-offs. Boys in the High BLL/High BML group had significantly lower RHR (mean = 84.22 beats per minute [bpm], SD = 8.77, n = 61) than boys in the Low BLL/Low BML group (mean = 89.03 bpm, SD = 10.75, n = 69; p < 0.05). BML and BLL did not interact to predict RHR in girls (B = -0.18, SE = 0.88, p > 0.05, n = 242). Combined high BLL and BML were associated with low RHR in community adolescent boys. Low RHR is an indication of chronic under-arousal and has been implicated in psychopathology, particularly for externalizing behavior. Our findings may stimulate further communication and research in this area.

Toxic metal exposure as a possible risk factor for COVID-19 and other respiratory infectious diseases

Multiple medical, lifestyle, and environmental conditions, including smoking and particulate pollution, have been considered as risk factors for COronaVIrus Disease 2019 (COVID-19) susceptibility and severity. Taking into account the high level of toxic metals in both particulate matter (PM2.5) and tobacco smoke, the objective of this review is to discuss recent data on the role of heavy metal exposure in development of respiratory dysfunction, immunotoxicity, and severity of viral diseases in epidemiological and experimental studies, as to demonstrate the potential crossroads between heavy metal exposure and COVID-19 severity risk. The existing data demonstrate that As, Cd, Hg, and Pb exposure is associated with respiratory dysfunction and respiratory diseases (COPD, bronchitis). These observations corroborate laboratory findings on the role of heavy metal exposure in impaired mucociliary clearance, reduced barrier function, airway inflammation, oxidative stress, and apoptosis. The association between heavy metal exposure and severity of viral diseases, including influenza and respiratory syncytial virus has been also demonstrated. The latter may be considered a consequence of adverse effects of metal exposure on adaptive immunity. Therefore, reduction of toxic metal exposure may be considered as a potential tool for reducing susceptibility and severity of viral diseases affecting the respiratory system, including COVID-19.

The interaction of lead exposure and CCM3 defect plays an important role in regulating angiogenesis through eNOS/NO pathway

In this study, we aimed to explore the role of nitric oxide (NO) in regulating angiogenesis in cerebral cavernous malformations 3 gene (CCM3)-deficient mice exposed to lead during vascular development; further, we aimed to identify and study the potential mechanism involved as well. Angiogenesis was detected by whole mount immunofluorescent staining of retinal vessels in WT and CCM3^+/- mice. Brain microvascular endothelial cells (BMECs) isolated from WT and CCM3^+/- mice, primary HUVECs, and immortalized HUVECs (imHUVECs) (CCM3^+/+ and CCM3^-/-) were used and treated with lead acetate (PbAc). RT-PCR and Western blotting were used to detect the mRNA and protein expression of iNOS, eNOS, and VEGF genes. The results showed that both lead exposure and CCM3 gene deficiency adversely affected endothelial cell function, causing abnormal angiogenesis and vascular remodeling. The mRNA expression of eNOS and iNOS was significantly different in WT and CCM3^+/- BMECs (0.04 ± 0.001 vs. 0.016 ± 0.002; 0.26 ± 0.002 vs. 0.306 ± 0.002, respectively), and the expression of eNOS and iNOS in imHUVECs (CCM3^+/+ and CCM3^-/-) also increased after PbAc exposure. In conclusion, CCM3 gene-deficient mice were more susceptible to abnormal vascular development after low-level lead exposure, probably due to the release of NO.

Angiogenesis and lead (Pb): is there a connection?

Lead (Pb) is a toxic heavy metal ubiquitously distributed around the world, especially in industrial areas. Occupational and environmental exposures to Pb have detrimental effects on human health. Pb affects functioning of many systems of the human body, including the cardiovascular system. Angiogenesis, the process of new blood vessel formation, which makes critical contribution throughout life is deranged in various diseases. Excessive angiogenesis may result in different diseases including cancer. On the other spectrum, insufficient angiogenesis is observed in many diseases, such as atherosclerosis, hypertension, and cardiovascular disease. These disorders are also associated with occupational Pb exposure. In this paper, epidemiological and experimental studies are reviewed selectively for evidence in support of this hypothesis, that is, interactions between Pb and angiogenesis. We discuss the evidence for the possible mechanism of Pb impact on concentrations of angiogenic factors. Studies suggested that Pb exposure affects the level of angiogenic factors associated with angiogenesis regulation and promotion. Further research is needed, especially in the mechanisms in which Pb-induced vascular endothelial growth factor (VEGF) disregulation is present. We believe that characterizing the connection between Pb and angiogenesis will provide helpful information for the development of intervention strategies to reduce the adverse effects of Pb exposure.

Heavy metal pollution in Nanchang City and its health implication on traffic policemen

The purpose of this study is to evaluate the health effect of heavy metal pollution in air pollutants on traffic policemen. This study will facilitate the scientific evaluation of health status of traffic policemen. PM₁₀ samples were collected from industrial area, congested traffic area and residential area respectively in Nanchang City, and the concentrations of heavy metals were analyzed. The traffic policemen were examined through chest X-rays. The total of 637 urine samples and 142 blood samples have been collected, and the concentrations of Pb in samples were detected. Vehicle flux data of Nanchang City were collected from the Department of Transport's Traffic Management. Statistic analyses were carried out by statistics software of Excel 2003 and SPSS20.0, and the health effect of heavy metal pollution of PM₁₀ on the traffic policemen was evaluated. The discharge of pollutants from enterprises is an important reason for the high content of heavy metals in urban air pollution. With the rapid growth of urban traffic flow, Bayi Bridge becomes an important transportation hinge in Nanchang City, and the bidirectional traffic flow rate through the bridge at peak hours reached 99 vehicles per minute. The latent hazard of occupational harm on the traffic policemen caused by automobile exhaust is increasing. The concentration of Pb in the urine and blood samples from traffic policemen working in Nanchang City was 268.310 ± 177.031 and 22.873 ± 21.137 μg/L, respectively. Both results (2.04% of Pb in urine and 18.31% of Pb in blood) exceeded the highest limit of observed occupationally outdoor workers. This study provides an initial contribution for the assessment of city air pollution, esp. the health effect of heavy metal (Pb) pollution on traffic policemen.

Occupational exposure to metals and other elements in the tractor production

Background

Exposure to metals via air sampling in workplace has been extensively studied; however, the magnitude of individual exposure in various occupational groups may vary dramatically. The aim of this cross-sectional study was to ascertain exposure to selected metals from metal fumes in a series of typical workplaces of contemporary tractor production.

Methods

Ninety-eight (median age 41 (interquartile range (IQR) 23) years, all men) workers from Minsk Tractor Plant were categorized into four groups, including assembly shop workers (group 1); thermal shop staff (group 2); steelmakers (group 3) and welders (group 4). Hair samples (0.25 g) of each worker were tested for Ca, Mg, P, Cu, Fe, Zn, Al, Mn, Cr, Ni, Pb and Cd using atomic emission spectrophotometry. We then tested between-group differences of log-transformed element concentrations using analysis of variance, followed by logistic regression to determine the odds ratio (OR) with its 95% confidence interval (CI) of high exposure for four selected groups.

Results

The median work duration in workers was 6 (IQR 15) years, more in group 1 (10 (IQR 23)). Eight out of 12 included elements yielded significant between-group differences, including Mg, P, Fe, Zn, Mn, Cr, Ni and Cd. Steelmakers had higher Mn hair concentrations (F-ratio 10.41, p<0.001); whereas Fe (F-ratio 12.48, p<0.001), P (F-ratio 12.68, p<0.001), Zn (F-ratio 6.07, p<0.001) and Cr (F-ratio 20.54, p<0.001) were higher in welders. OR of high exposure to Mg in group 3 was 10.00 (95% CI 1.14–87.52), whereas the OR of high exposure to P in group 4 was 18.64 (95% CI 2.22–156.85) compared to group 1.

Conclusions

In the modern full-cycle tractor production, welders may have higher exposure to Fe, P, Zn and Cr, as opposed to steelmakers with higher Mn hair concentrations.

High Content of Lead Is Associated with the Softness of Drinking Water and Raised Cardiovascular Morbidity: A Review

Daily ingestion of lead (Pb), even through piped drinking water, has long time been an important issue of concern, attracting for decades research in environmental science and toxicology, and again comes to prominence because of recent high-profile cases of exposure of populations in several countries to Pb-contaminated water. Numerous studies have reported an association between Pb in water and the risk of cardiovascular pathologies. Low levels of magnesium and calcium, i.e., low degree of hardness of the drinking water, may accentuate Pb leaching from water pipes and furthermore increase Pb absorption. This review evaluates the evidence for an association between Pb exposure from drinking water and cardiovascular end points in human populations.

The effect of subacute lead exposure on selected blood inflammatory biomarkers and angiogenetic factors

Objectives:

The aim of the study was to examine blood levels of selected pro-inflammatory cytokines, C reactive protein (CRP), and selected factors that influence angiogenesis in workers exposed to lead for a short period of time.

Methods:

The study population consisted of 36 male workers (mean age 41 ± 14 years) exposed to lead for 40 days.

Results:

The mean blood lead level (BLL) was 10.7 ± 7.67 μg/dl at the beginning of the study, and increased to 49.1 ± 14.1 μg/dl at the end of the study period. The levels of macrophage inflammatory protein 1-α (MIP-1α) were significantly higher after the studied exposure to lead compared to the baseline by 71%. Similarly, the values of CRP increased by 35%. Conversely, the values of soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) and fibroblast growth factor-basic (FGF-basic) decreased by 14% and 21%, respectively. After the examined period of lead exposure, analysis of correlations showed positive correlations between vascular endothelial growth factor (VEGF) levels and the levels of interleukin 1β (IL-1β) (R = 0.39), interleukin 6 (IL-6) (R = 0.42), and MIP-1α (R = 0.54). Positive correlations were identified between MIP-1α and FGF-basic (R = 0.38), soluble angiopoietin receptor (sTie-2) (R = 0.41), and sVEGFR-1 (R = 0.47).

Discussion:

Short-term exposure to lead induces the inflammatory response; however, these mechanisms seem to be different from those observed in chronic lead exposure. Subacute exposure to lead may dysregulate angiogenesis via modifications in the levels of angiogenic factors.

Association between blood lead level and blood pressure: An occupational population-based study in Jiangsu province, China

Studies about the association between lead exposure and the elevation of blood pressure and risk of hypertension are varied, while available data on blood lead levels (BLL) in workers with lead-exposure are scarce. This research aimed to evaluate associations between BLL and blood pressure in an occupational population-based study in Jiangsu province, China. We enrolled 21,688 workers in this study. Information on socioeconomic and occupational background was obtained with face-to-face interviews. BLL, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured, and hypertension status was confirmed. We found that workers in mini-factories had the highest average BLL (20.3 μg/dL; 95% CI, 19.0-21.6 μg/dL) for overall participants. The employees in private factories had higher BLL (9.6 μg/dL; 95% CI, 9.5-9.8 μg/dL). However, BLL was much lower (4.0 μg/dL; 95%CI, 3.7-4.2 μg/dL) in state-owned factories. Participants working in the electrical machinery and equipment manufacturing industry had higher BLL (9.1 μg/dL; 95% CI, 9.0-9.3μg/dL). Compared to those workers with ≤ 4.6 μg/dL BLL, workers with > 17.5 μg/dL BLL presented 1.34 mmHg and 0.70 mmHg average difference in SBP and DBP, respectively. The adjusted OR for hypertension was 1.11 (95%CI, 1.08-1.15) compared to the workers with > 17.5 μg/dL BLL and to those with ≤ 4.6 μg/dL BLL. In summary, we found that BLL was positively associated with SBP and DBP and with the morbidity of hypertension in occupational populations with a high concentration of lead exposure. It is important to formulate new standards of blood lead levels to screen for elevated lead exposure. In addition, a series of new systems of risk assessment should be established to further reduce and prevent lead exposure.

The association between occupational lead exposure and serum levels of selected soluble receptors

The present study was designed to evaluate soluble receptors as potential targets for lead (Pb). Analyses included the serum levels of soluble Vascular Endothelial Growth Factor Receptors 2 (sVEGFR-2), soluble Epidermal Growth Factor Receptor (sEGFR), soluble Human Epidermal Growth Factor 2 (sHER-2/neu), and soluble Interleukin 6 Receptors (sIL-6R) in the groups of chronically and subchronically occupationally exposed workers. The first group consisted of 56 male workers chronically exposed to Pb. The second group (control) comprised 24 male administrative workers. The third group included 36 male workers exposed to Pb for 40 ± 3 days. Examined subjects were employed in the Pb-zinc works to perform periodic maintenance of blast furnaces and production lines. The serum levels of sHER-2/neu and sIL-6R were significantly lower in the group of workers chronically exposed to Pb compared to control values by 45% ( p < 0.05) and 44% ( p < 0.05), respectively. The values of sVEGFR-2 and sEGFR decreased after a subchronic exposure to Pb compared to baseline by 14% ( p < 0.05) and 21% ( p < 0.05), respectively. At the same time, the levels of sIL-6R also decreased by 14% ( p < 0.05). Results of the present study indicated that both chronic and subchronic occupational Pb exposures resulted in decreased levels of several soluble receptors (sVEGFR-2, sEGFR, sHER-2/neu, and sIL-6R), probably due to Pb-induced modulations of the transcription factors and metalloprotease activities, that are necessary for soluble receptor synthesis.

Elevated inflammatory Lp-PLA2 and IL-6 link e-waste Pb toxicity to cardiovascular risk factors in preschool children

Cardiovascular toxicity of lead (Pb) manifests primarily as an effect on blood pressure and eventual increased risk of atherosclerosis and cardiovascular events. Therefore, we investigated vascular inflammatory biomarkers and cardiovascular effects of Pb-exposed children. A total of 590 children (3-7 years old) were recruited from Guiyu (n = 337), an electronic waste (e-waste)-exposed group, and Haojiang (n = 253), a reference group, from November to December 2016. We measured child blood Pb levels (BPbs), and systolic and diastolic blood pressure. Pulse pressure was calculated for the latter two. Serum biomarkers including lipid profiles and inflammatory cytokines, and plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) were detected. Unadjusted regression analysis illustrated that higher ln-transformed BPb associated with lower systolic blood pressure and pulse pressure. After adjustment for various confounders, the relational degree of lnBPb and blood pressure measures became slightly attenuated or not significant. Elevated BPb was associated with higher Lp-PLA2, interleukin (IL)-6, triglycerides (TG) and lower high-density lipoprotein (HDL). Lp-PLA2 remained inversely associated with pulse pressure and HDL, but positively with ratios of total cholesterol to HDL (Tc/HDL) and low-density lipoprotein to HDL (LDL/HDL). IL-6 was associated negatively with systolic blood pressure, pulse pressure and HDL, and positively associated with TG, Tc/HDL and LDL/HDL. The mediation effect of biomarkers on the association of BPb with pulse pressure was insignificant except for Lp-PLA2. Available data supports the conclusion that e-waste-exposed children with higher BPbs and concomitant abnormal measures of cardiovascular physiology have an augmented prevalence of vascular inflammation, as well as lipid disorder.

Association between Exposure to Ambient Air Particulates and Metabolic Syndrome Components in a Saudi Arabian Population

Recent epidemiological evidence suggests that exposure to particulates may be a factor in the etiology of metabolic syndrome (MetS). In this novel study, we investigated the relationship between particulate levels and prevalence of MetS component abnormalities (hypertension, hyperglycemia, obesity) in a recruited cohort (N = 2025) in Jeddah, Saudi Arabia. We observed significant associations between a 10 μg/m³ increase in PM_2.5 and increased risks for MetS (Risk Ratio (RR): 1.12; 95% Confidence Interval (CI): 1.06-1.19), hyperglycemia (RR: 1.08; 95% CI: 1.03-1.14), and hypertension (RR: 1.09; 95% CI: 1.04-1.14). PM_2.5 from soil/road dust was found to be associated with hyperglycemia (RR: 1.12; 95% CI: 1.06-1.19) and hypertension (RR: 1.11; 95% CI: 1.05-1.18), while PM_2.5 from traffic was associated with hyperglycemia (RR: 1.33; 95% CI: 1.05-1.71). We did not observe any health associations with source-specific mass exposures. Our findings suggest that exposure to specific elemental components of PM_2.5, especially Ni, may contribute to the development of cardiometabolic disorders.

Disparities of Selected Metal Levels in the Blood and Scalp Hair of Ischemia Heart Disease Patients and Healthy Subjects

Imbalances in the concentrations of trace metals have become an increasingly recognized source of infirmity worldwide particularly in the development of ischemia heart disease (IHD). Present study is intended to analyze the concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn in the blood and scalp hair of the patients and counterpart controls by flame atomic absorption spectrometry after wet-acid digestion. On the average, Cd, Co, Cr, Fe, K, Li, Mn, Na, and Pb revealed significantly elevated concentrations in the blood of the patients compared with the controls (p < 0.05), whereas mean levels of Ca, Cd, Fe, K, Li, Pb, and Sr in the scalp hair were significantly higher in the patients than the controls (p < 0.05). Most of the metals exhibited noticeable disparities in their concentrations based on gender, abode, dietary/smoking habits, and occupations of both donor groups. The correlation study and multivariate statistical analyses revealed some significantly divergent associations and apportionment of the metals in both donor groups. Overall, comparative variations of the metal contents in blood/scalp hair of the patients were significantly different than the controls; thus, evaluation of trace metals status may be indicative of pathological disorders, such as IHD.

Genetic variability in the system of natriuretic B peptide and principal toxicological parameters in workers exposed to lead

The study was aimed at evaluating the influence of selected polymorphisms of natriuretic peptide B precursor (NPPB) and natriuretic peptide receptor C (NPR3) genes on blood lead concentration (Pb-B) and blood zinc protoporphyrin concentration (ZnPP) in persons occupationally exposed to lead. Investigations were conducted on 360 persons (mean age: 44.49±9.62years), workers exposed to lead compounds. The analysis examined four polymorphisms of BNP gene, i.e.,: rs198388, rs198389, rs632793, and rs6676300; as well as one polymorphism of receptor C for natriuretic peptides, i.e., rs1421811. Heterozygosity in locus rs632793 of NPPB gene may result in higher concentrations of Pb-B, while allele A in locus rs632793 of NPPB gene seems to determine higher concentrations of ZnPP in persons occupationally exposed to lead. Workers exposed to lead and carrying allele C in locus rs198388 of NPPB gene, particularly in the heterozygotic setup, seem to be predisposed to present higher concentrations of ZnPP. Carriership of A allele in locus rs198389 of NPPB gene probably determines higher concentrations of ZnPP in study group. In summary, among persons occupationally exposed to lead, certain relationships were demonstrated between rs632793, rs198388 and rs198389 polymorphisms of NPPB gene and principal toxicological parameters characterizing exposure to lead.

Potential sources and racial disparities in the residential distribution of soil arsenic and lead among pregnant women

Exposure to arsenic (As) or lead (Pb) has been associated with adverse health outcomes, and high-risk populations can be disproportionately exposed to these metals in soils. The objectives of this study were: to examine if predicted soil As and Pb concentrations at maternal residences of South Carolina (SC) low-income mothers differed based on maternal race (non-Hispanic black versus white), to examine whether differences in predicted residential soil As and Pb concentrations among black and white mothers differed by socioeconomic status (SES), and to examine whether such disparities persisted after controlling for anthropogenic sources of these metals, including direction from, and distance to industrial facilities. Kriged soil As and Pb concentrations were estimated at maternal residences in 11 locations in SC, and models with maternal race and individual and US Census block group level SES measures were examined. US Environmental Protection Agency Toxics Release Inventory (TRI) facility As and Pb releases categorized by distance and direction to block groups in which mothers resided were also identified, as were proxy measures for historic use of leaded gasoline (road density) and Pb-based paint (categories of median year home built by US Census block group). Consistent racial disparities were observed for predicted residential soil As and Pb concentrations, and the disparity was stronger for Pb than As (betas from adjusted models for black mothers were 0.12 and 2.2 for As and Pb, respectively, all p<0.006). Higher road density and older homes in block groups were more closely associated with higher predicted soil As and Pb concentrations than on-site releases of As and Pb categorized by facility location. These findings suggest that non-Hispanic black mothers in this study population had elevated residential As and Pb soil concentrations, after adjusting for SES, and that soil As and Pb concentrations were not associated with recent industrial releases.

Lead toxicity promotes autonomic dysfunction with increased chemoreceptor sensitivity

Mortality and morbidity by toxic metals is an important issue of occupational health. Lead is an ubiquitous heavy metal in our environment despite having no physiological role in biological systems. Being an homeostatic controller is expected that the autonomic nervous system would show a degree of impairment in lead toxicity. In fact, sympathoexcitation associated to high blood pressure and tachypnea has been described together with baroreflex dysfunction. However, the mechanisms underlying the autonomic dysfunction and the interplay between baro- and chemoreflex are not yet fully clarified. The angiotensinogenic PVN-NTS axis (paraventricular nucleus of the hypothalamus - nucleus tractus solitarius axis) is a particularly important neuronal pathway that could be responsible for the autonomic dysfunction and the cardiorespiratory impairment in lead toxicity. Within the current work, we addressed in vivo, baro- and chemoreceptor reflex behaviour, before and after central angiotensin inhibition, in order to better understand the cardiorespiratory autonomic mechanisms underlying the toxic effects of long-term lead exposure. For that, arterial pressure, heart rate, respiratory rate, sympathetic and parasympathetic activity and baro- and chemoreceptor reflex profiles of anaesthetized young adult rats exposed to lead, from foetal period to adulthood, were evaluated. Results showed increased chemosensitivity together with baroreceptor reflex impairment, sympathetic over-excitation, hypertension and tachypnea. Chemosensitivity and sympathetic overexcitation were reversed towards normality values by NTS treatment with A-779, an angiotensin (1-7) antagonist. No parasympathetic changes were observed before and after A-799 treatment. In conclusion, angiotensin (1-7) at NTS level is involved in the autonomic dysfunction observed in lead toxicity. The increased sensitivity of chemoreceptor reflex expresses the clear impairment of autonomic outflow to the cardiovascular and respiratory systems induced by putative persistent, long duration, alert reaction evoked by the long term exposure to lead toxic effects. The present study brings new insights on the central mechanisms implicated in the autonomic dysfunction induced by lead exposure which are relevant for the development of additional therapeutic options to tackle lead toxicity symptoms.

Abnormalities of Selected Trace Elements in Patients with Coronary Artery Disease

BACKGROUND

Coronary artery diseases are multifactorial, and over the last several decades particular consideration and research have been devoted to investigating the imbalance of patient elemental levels. Our current study aimed to investigate the comparative distribution of Ca, Mg, Fe, Zn, Cu, Co, Mn, Cr, Cd and Pb in the blood of coronary artery disease patients and healthy subjects.

METHODS

Blood samples collected from both groups were digested into a HNO3-HCLO4 (10:1 v/v) mixture in a microwave oven, followed by quantification of the elements by atomic absorption spectrometry.

RESULTS

The average levels of Pb and Cr were markedly higher (p < 0.001) while those of Ca, Fe, Cu and Mn were moderately higher (p < 0.05) in blood of the patients compared to the controls. However, correlation study showed divergent relationships between various elements in the blood of both groups. Multivariate cluster analysis revealed two major clusters of the elements for patients: Ca-Mg-Mn-Co-Cd and Pb-Cu-Fe-Zn-Cr; whereas three common groups were observed for controls: Ca-Mg-Zn-Cu, Cr-Mn-Fe and Co-Cd-Pb. Variations in the elemental levels were also observed to be associated with gender, habitat, food and smoking habits of the subjects.

CONCLUSIONS

Overall, the distribution, correlation and apportionment of elemental data indicated an imbalance of the toxic/essential elements in blood of the patients compared to the controls.

KEY WORDS

AAS; Blood; Cluster analysis; Coronary artery disease; Essential/toxic element.

Heavy Metals and Human Health: Mechanistic Insight into Toxicity and Counter Defense System of Antioxidants

Heavy metals, which have widespread environmental distribution and originate from natural and anthropogenic sources, are common environmental pollutants. In recent decades, their contamination has increased dramatically because of continuous discharge in sewage and untreated industrial effluents. Because they are non-degradable, they persist in the environment; accordingly, they have received a great deal of attention owing to their potential health and environmental risks. Although the toxic effects of metals depend on the forms and routes of exposure, interruptions of intracellular homeostasis include damage to lipids, proteins, enzymes and DNA via the production of free radicals. Following exposure to heavy metals, their metabolism and subsequent excretion from the body depends on the presence of antioxidants (glutathione, α-tocopherol, ascorbate, etc.) associated with the quenching of free radicals by suspending the activity of enzymes (catalase, peroxidase, and superoxide dismutase). Therefore, this review was written to provide a deep understanding of the mechanisms involved in eliciting their toxicity in order to highlight the necessity for development of strategies to decrease exposure to these metals, as well as to identify substances that contribute significantly to overcome their hazardous effects within the body of living organisms.

Comparative Study of Elemental Concentrations in the Scalp Hair and Nails of Myocardial Infarction Patients Versus Controls from Pakistan

Ischemia heart disease has become a ubiquitous cause of morbidity and a leading contributor to mortality worldwide. The present study was aimed to quantify the elemental levels for Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb, Sr, and Zn in the scalp hair and nails of myocardial infarction (MI) patients and counterpart controls by flame atomic absorption spectrophotometry. The effects of elemental imbalances on the development of atherosclerosis were evaluated. Average concentrations of Pb (14.7 μg/g), Sr (21.6 μg/g), and Cr (3.70 μg/g) were significantly higher in the scalp hair of the patients, while those of Na, K, Mg, Fe, Mn, and Cd were measured at almost comparable levels in the scalp hair of the patients and controls. In the case of nail samples, average concentrations of Na (1260 μg/g), K (873 μg/g), Sr (70.9 μg/g), Cu (16.6 μg/g), and Mn (16.9 μg/g) were significantly higher in the patients than controls. The correlation study revealed significantly divergent mutual variations among the elements in MI patients and controls. Principal component analysis also manifested the diverse apportionment of the elements in both donor groups. Most of the elements revealed significant disparities in their concentrations based on gender, abode, and smoking habits of the donors in both groups. In conclusion, the elemental imbalance has potential proatherogenic effect that would have a significant impact on sensitive population groups.

Does maternal VDR FokI single nucleotide polymorphism have an effect on lead levels of placenta, maternal and cord bloods?

INTRODUCTION

Individual susceptibility due to genetic variations appears to be an important factor in lead toxicity. As lead, ubiquitous atmospheric pollutant, behaves very similarly to calcium, gene polymorphisms in proteins involved in calcium homeostasis can affect lead toxicokinetics. Vitamin D receptor (VDR), a DNA-binding transcription factor, activates genes that encode proteins involved in calcium metabolism. Thus, the objective of this study was to determine the effect of maternal VDR FokI polymorphism on lead levels of maternal blood, placental tissue and cord blood.

METHODS

The study population comprised 116 women and their respective placenta and umbilical cord. Venous blood samples were drawn from mothers to investigate both the lead levels and VDR FokI polymorphism. Cord blood samples and placentas were collected for lead levels. VDR FokI polymorphism was detected by standard polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. Lead levels were analyzed by dual atomic absorption spectrometer system.

RESULTS

Genotype frequencies of VDR FokI polymorphism were 49.2% FF, 44.8% Ff and 6.0% ff. The mean lead levels of maternal blood, placenta and cord blood were 36.76 ± 13.84 μg/L, 12.84 ± 14.47 μg/kg and 25.69 ± 11.12 μg/L, respectively. Maternal blood, placental and cord blood lead levels were found significantly to be higher in mothers with f allele for the VDR FokI polymorphism (p < 0.05).

DISCUSSION

The present study indicated that this polymorphism had an effect on maternal and fetal lead levels and that mothers with F allele associated with lower lead concentration may protect their respective fetus against the toxic effects of lead exposure.

Genetic Effects of eNOS Polymorphisms on Biomarkers Related to Cardiovascular Status in a Population Coexposed to Methylmercury and Lead

The aim of the present study was to evaluate possible effects of endothelial nitric oxide synthase (eNOS) polymorphisms on systolic (SBP) and diastolic blood pressure (DBP) and on nitrite levels in plasma (NitP) in a population coexposed to methylhemoglobin (MeHg) and lead (Pb) in the Amazonian region, Brazil. Plasmatic levels of hemoglobin Hg (HgP) and Pb (PbP) were determined by inductively coupled plasma-mass spectrometry, whereas NitP were quantified by chemiluminescence. Genotyping was performed by conventional and restriction fragment length polymorphism-polymerase chain reaction assay. The population age ranged from 18 to 87 years (mean 40 ± 16), and the distribution between the sexes was homogenous (63 men and 50 women). Mean HgP and PbP were 7.1 ± 6.1 and 1.1 ± 1.1 µg L(-1), respectively. PbP was correlated to SBP and DBP, whereas no effects were observed for HgP on blood pressure. Subjects carrying the 4b allele in intron 4 presented greater SBP and DBP compared with those who had the 4a4a genotype. In addition, interactions between alcohol consumption and the -786 T/C polymorphism were observed on NitP, i.e., individuals carrying the polymorphic allele and drinkers had lower NitP. Taken together, our data give new insights concerning the genetic effects of eNOS polymorphisms on biomarkers related to cardiovascular status in populations coexposed to Hg and Pb.

Function of respiratory system evaluated using selected spirometry parameters in persons occupationally exposed to lead without evident health problems

This study aimed at evaluation of selected spirometric parameters in persons occupationally exposed to lead without evident health problems. The studies were conducted on 69 men occupationally exposed to lead. Occupational exposure to lead was characterized by estimation of blood lead concentration (Pb-B) and blood zinc protoporphyrin concentration (ZnPP). Function of respiratory system was examined using spirometric analysis with evaluation of its basic parameters: forced vital capacity (FVC), forced expiratory volume (in 1s) (FEV1), Tiffeneau index (FEV1%VC) and peak expiratory flow (PEF). In the study group negative linear correlations were documented between Pb-B and FVC, FEV 1 and FEV1%VC. A more pronounced age, higher values of BMI and higher blood lead concentration constituted independent risk factors for reduced FEV1%VC.

CONCLUSION

Persons occupationally exposed to lead with elevated blood lead concentration and blood zinc protoporphyrin concentration manifested the impaired function of respiratory system, evaluated using parameters of spirometry.

Functionalization of cationic poly(p-phenylene ethynylene) with dendritic polyethylene enables efficient DNAzyme delivery for imaging Pb2+ in living cells

We report here an effective Pb²⁺-dependent DNAzyme (8-17 DNAzyme) delivery system based on the water-soluble dendritic polyethylene-cationic poly(p-phenylene ethynylene) for successfully imaging Pb²⁺ in living cells. For utilizing the 8-17 DNAzyme and its unique ability to catalyze a phosphodiester bond cleavage reaction in the presence of Pb²⁺, the distinctive conjugated polymer-based polyvalent nanocarrier design manages to load and transport 8-17 DNAzyme across cell membranes, and to realize the fluorescence imaging of Pb²⁺ in living cells. As shown by the confocal microscopy and flow cytometry observations, the fluorescence of Cy5.5 is obviously activated under the conditions of incubation with Pb²⁺, compared with the absence of Pb²⁺. Taken together, the study demonstrates the combination of the molecular-wire effect with "dendrimer effects" on their effective DNAzyme delivery and their cellular imaging Pb²⁺.

Environmental epigenetics and its implication on disease risk and health outcomes

This review focuses on how environmental factors through epigenetics modify disease risk and health outcomes. Major epigenetic events, such as histone modifications, DNA methylation, and microRNA expression, are described. The function of dose, duration, composition, and window of exposure in remodeling the individual's epigenetic terrain and disease susceptibility are addressed. The ideas of lifelong editing of early-life epigenetic memories, transgenerational effects through germline transmission, and the potential role of hydroxylmethylation of cytosine in developmental reprogramming are discussed. Finally, the epigenetic effects of several major classes of environmental factors are reviewed in the context of pathogenesis of disease. These include endocrine disruptors, tobacco smoke, polycyclic aromatic hydrocarbons, infectious pathogens, particulate matter, diesel exhaust particles, dust mites, fungi, heavy metals, and other indoor and outdoor pollutants. We conclude that the summation of epigenetic modifications induced by multiple environmental exposures, accumulated over time, represented as broad or narrow, acute or chronic, developmental or lifelong, may provide a more precise assessment of risk and consequences. Future investigations may focus on their use as readouts or biomarkers of the totality of past exposure for the prediction of future disease risk and the prescription of effective countermeasures.

The relationship between environmental exposure to cadmium and lead and blood selenium concentration in randomly selected population of children inhabiting industrial regions of Silesian Voivodship (Poland)

This study aimed at determining the relationship between environmental exposure to lead (Pb) and cadmium (Cd) and blood selenium (Se) concentration in randomly selected population of children inhabiting the industrial regions of Silesian Voivodship, Poland. The study was conducted on a group of consecutive randomly selected 349 children aged below 15 years and inhabiting the industrial regions in Upper Silesia. The examined variables included whole blood Cd concentration (Cd-B), whole blood Pb concentration (Pb-B) and whole blood Se concentration (Se-B). The concentration of Cd-B, Pb-B and Se-B in the studied group of children amounted to 0.26 ± 0.14, 37.62 ± 25.30 and 78.31 ± 12.82 μg/L, respectively. In the entire examined group a statistically significant negative linear relationship was noted between Pb-B and Se-B (r = -0.12, p < 0.05). Also, a statistically insignificant negative correlation was detected between Cd-B and Se-B (r = -0.02, p > 0.05) and a statistically insignificant positive correlation between Pb-B and Cd-B (r = 0.08, p > 0.05). A multivariate backward stepwise regression analysis demonstrated that in the studied group of children higher Pb-B and a more advanced age-represented independent risk factors for a decreased Se-B. Environmental exposure to Pb may represent an independent risk factor for Se deficit in blood of the studied population of children. In children, the lowered Se-B may create one of the mechanisms in which Pb unfavourably affects human body.

Development and in vitro evaluation of a novel lipid nanocapsule formulation of etoposide

Small cell lung cancer (SCLC) is the most aggressive carcinoma in thoracic oncology, unfortunately, despite chemotherapy, relapse is constant. The effect of etoposide, a major drug used against SCLC, can potentially be enhanced after its encapsulation in nanocarriers. The aim of this study was to use the technology of lipid nanocapsules (LNCs) to obtain nanocarriers with drug loadings compatible with clinical use and with an industrial process. Solubility studies with different co-solvent were first performed, then several process were developed to obtain LNCs. LNCs were then characterized (size, zeta potential, and drug loading). The best formulation called Ω-LNCs had a size of 54.1±2.0 nm and a zeta potential of -5.8±3.5 mV and a etoposide drug loading of 5.7±0.3mg/g. The characteristics of this formulation were maintained after freeze drying and after a 15× scale-up. Release studies in a media mimicking plasma composition showed that 40% of the drug was released from the LNCs after 48 h. Moreover the activity of etoposide after encapsulation was enhanced on H209 cells, IC50 was 100 μM and 2.5 μM for etoposide and etoposide LNCs respectively. Unfortunately the formulation failed to be more cytotoxic than etoposide alone on H69AR cells that are resistant to etoposide. This study showed that is was possible to obtain a new etoposide nanocarrier without the use of organic solvent, that the process is suitable for scale-up and freeze drying and finally that etoposide activity is maintained which is very promising for future treatment of SCLC.

Colorimetric assay of lead ions in biological samples using a nanogold-based membrane

We have developed a simple paper-based colorimetric membrane for sensing lead ions (Pb(2+)) in aqueous solutions. The nitrocellulose membrane (NCM) was used to trap bovine serum albumin (BSA) modified 13.3-nm Au nanoparticles (BSA-Au NPs), leading to the preparation of a nanocomposite film of a BSA-Au NP-decorated membrane (BSA-Au NPs/NCM). The BSA-Au NPs/NCM operates on the principle that Pb(2+) ions accelerate the rate of leaching of Au NPs induced by thiosulfate (S(2)O(3)(2-)) and 2-mercaptoethanol (2-ME). The BSA-Au NPs/NCM allowed for the detection of Pb(2+) by the naked eye in nanomolar aqueous solutions in the presence of leaching agents such as S(2)O(3)(2-) and 2-ME. We employed the assistance of microwave irradiation to shorten the reaction time (<10 min) for leaching the Au NPs. Under optimal solution conditions (5 mM glycine-NaOH (pH 10), S(2)O(3)(2-) (100 mM), and 2-ME (250 mM), microwaves (450 W)), the BSA-Au NPs/NCM allowed the detection of Pb(2+) at concentrations as low as 50 pM with high selectivity (at least 100-fold over other metal ions). This cost-effective sensing system allowed for the rapid and simple determination of the concentrations of Pb(2+) ions in real samples (in this case, sea water, urine, and blood samples).