Metals In Urine Samples Research Articles

Comparison of Heavy Metals in Urine Samples of Smoker and Non-smoker Persons.

In this study, the concentrations of heavy metals such as cadmium (Cd), chromium (Cr), and lead (Pb) in the two groups of cigarette smokers and non-smokers in five age range groups were measured. Heavy metal concentrations were collected in participants' urine samples and analyzed using atomic absorption spectrophotometry (AAS). The results showed that the concentrations of these metals in the urine of smokers were higher than in non-smoker subjects. The mean concentration of Cd, Cr, and Pb for smokers were 1.188 ± 0.931, 1.929 ± 0.940, and 0.069 ± 0.023, respectively, while the mean concentration of Cd, Cr, and Pb for non-smokers were 0.151 ± 0.165, 0.203 ± 0.218, and 0.037 ± 0.030, respectively. The results revealed statistically significant differences when comparing the samples of smokers to the control group in all heavy metals in the present study. Also, the results revealed statistically significant differences in Cd, Cr, and Pb when comparing the samples of smokers to age groups. The trend of metals in urine samples in two groups (smokers and non-smokers) is as follows: Cd > Cr > Pb. The concentration of Cd, Cr, and Pb in all samples of the present study was higher than the biological limit, according to ACGIH. Therefore, Cd, Cr, and Pb were the most critical metals accumulated in the urine of cigarette smokers.

Urinary concentrations of heavy metals in pregnant women living near a petrochemical area according to the industrial activity

BackgroundThe progressive industrialization has resulted in an increase in heavy metal pollution in the environment, which has a dangerous impact on human health. Prenatal exposure to heavy metals, even at very low concentrations, may be especially harmful to pregnant women and their children. Different industrial activities can contribute to heavy metal pollution in a specific area. Objective1) To explore the concentrations of heavy metals in urine samples of pregnant women, and 2) to evaluate the potential effect of different industrial activities in Tarragona (Spain). MethodsUrinary levels of four heavy metals (nickel (Ni), cadmium (Cd), mercury (Hg), and lead (Pb)) from 368 pregnant women recruited in the ECLIPSES study were analyzed. Home addresses and all the industries potentially releasing heavy metals were geo-referenced. Buffer zones were established within a 1.5, 3, and 5 km radius at the center of each industry. Subsequently, the number of participants living in and out of each buffer zone was recorded. ResultsUrinary levels of Ni and Cd, but not those of Hg and Pb, were obviously increased in pregnant women living near most of the industrial sites. After adjustment for potential co-variates, only Cd showed notable differences according to the industrial activity. Compared to women living outside the buffer, Cd levels were increased in those living within 1.5 and 3 km of chemical industries, within 5 km of energy industries, within 1.5, 3, and 5 km of mineral industries, and within 3 and 5 km of metal processing industries. ConclusionAmong the analyzed heavy metals, Cd showed an increasing trend in urinary concentrations in women living near chemical, energy, mineral, and metal processing industries. This study highlights the need to develop legislative measures to minimize Cd exposure, especially by sensitive populations. Moreover, additive or synergistic effects of co-exposure to other air pollutants should not be disregarded.

Association between urinary metal concentrations and abnormal estimated glomerular filtration rate in Chinese community-dwelling elderly: Exploring the mediating effect of triglycerides

BackgroundEnvironmental metal exposure is associated with elevated triglycerides (TG) and the development of chronic kidney disease (CKD). However, the relationship between metal exposure and glomerular filtration rate (GFR) remains uncertain, and the mediating effect of TG between the two is unclear. MethodsThis study measured the concentrations of 14 metals in urine samples from 3752 elderly people in the community. The most relevant metals were screened by least absolute shrinkage and selection operator (LASSO) regression. The relationship between combined exposure to multiple metals and abnormal estimated glomerular filtration rate (eGFR) was explored using multivariate logistic regression analysis and Bayesian kernel machine regression (BKMR) analysis. Generalized linear regression models and the Karlson-Holm-Breen (KHB) method were used to assess the mediating effects of TG. ResultsIn the single-metal model, calcium (Ca), iron (Fe), selenium (Se), strontium (Sr), and thallium (Tl) showed significant negative correlations with the prevalence of abnormal eGFR (all P < 0.05). In the multi-metals model, Ca, Se, and Tl continued to show significant negative correlations, while vanadium (V) and zinc (Zn) showed significant positive correlations with abnormal eGFR (all P < 0.05). The BKMR model showed a negative joint effect of the mixture of Ca, V, Zn, Se, and Tl on the prevalence of abnormal eGFR. The generalized linear regression model showed a significant positive correlation between the concentrations of Ca (β = 0.07), Zn (β = 0.07), Se (β = 0.09), and TG levels (all P < 0.05). In the mediation analysis, TG masked a 4.30% and 5.21% correlation between Ca and Se and the prevalence of eGFR abnormalities, respectively. ConclusionsUrinary concentration of multiple metals is significantly associated with eGFR abnormalities, and Ca, and Se may be among the potential protective factors. TG masked some of the protective effects of Ca and Se.

Maternal Urinary Metal and Metalloid Concentrations in Association with Oxidative Stress Biomarkers.

Metal exposure has been associated with a wide range of adverse birth outcomes and oxidative stress is a leading hypothesis of the mechanism of action of metal toxicity. We assessed the relationship between maternal exposure to essential and non-essential metals and metalloids in pregnancy and oxidative stress markers, and sought to identify windows of vulnerability and effect modification by fetal sex. In our analysis of 215 women from the PROTECT birth cohort study, we measured 14 essential and non-essential metals in urine samples at three time points during pregnancy. The oxidative stress marker 8-iso-prostaglandin F2α (8-iso-PGF2α) and its metabolite 2,3-dinor-5,6-dihydro-15-15-F2t-IsoP, as well as prostaglandin F2α (PGF2α), were also measured in the same urine samples. Using linear mixed models, we examined the main effects of metals on markers of oxidative stress as well as the visit-specific and fetal sex-specific effects. After adjustment for covariates, we found that a few urinary metal concentrations, most notably cesium (Cs) and copper (Cu), were associated with higher 8-iso-PGF2α with effect estimates ranging from 7.3 to 14.9% for each interquartile range, increase in the metal concentration. The effect estimates were generally in the same direction at the three visits and a few were significant only among women carrying a male fetus. Our data show that higher urinary metal concentrations were associated with elevated biomarkers of oxidative stress. Our results also indicate a potential vulnerability of women carrying a male fetus.

EDTA Chelation Therapy in the Treatment of Neurodegenerative Diseases: An Update.

We have previously described the role played by toxic-metal burdens in the etiology of neurodegenerative diseases (ND). We herein report an updated evaluation of toxic-metal burdens in human subjects affected or not affected by ND or other chronic diseases. Each subject underwent a chelation test with the chelating agent calcium disodium ethylenediaminetetraacetic acid (CaNA2EDTA or EDTA) to identify the presence of 20 toxic metals in urine samples using inductively coupled plasma mass spectrometry. Our results show the constant presence of toxic metals, such as lead, cadmium, cesium, and aluminum, in all examined subjects but the absence of beryllium and tellurium. Gadolinium was detected in patients undergoing diagnostic magnetic resonance imaging. The presence of toxic metals was always significantly more elevated in ND patients than in healthy controls. Treatment with EDTA chelation therapy removes toxic-metal burdens and improves patient symptoms.

Abstract P452: Urinary Metal Levels After Repeated Chelation With Edetate Disodium: Additional Evidence in Support of Metals as Cardiovascular Risk Factors

Background: Epidemiologic evidence supports lead and cadmium as CVD risk factors. In the Trial to Assess Chelation Therapy (TACT), edetate disodium infusions lowered CVD risk in patients with a prior myocardial infarction. The impact of repeated chelation on established biomarkers of metal body burden, post-chelation lead and pre-chelation urine cadmium, is unknown. Objective: To assess metals in urine samples collected at the first and at 10 or more infusions with edetate disodium. We hypothesized that post-chelation urine lead and pre-chelation urine cadmium would be lower after 10 infusions compared to the first infusion. Other metals were exploratory. Methods: 13 patients with coronary artery disease (CAD) received a median of 3 g of edetate disodium over 3h per infusion and a median of 51 infusions (range 22-61). We collected pre and post-chelation urine samples at infusions 1 and ≥10. Metals were analyzed with ICPMS and controlled for urine dilution. Pre and post-chelation geometric means (GM) of urine metals at the ≥10 vs. first infusion were compared using paired T-tests. Results: Mean (SD) age was 75 (11) years, 77% participants were men, 46% were past smokers, 92% had diabetes, and 92% had peripheral artery disease. Comparing infusions ≥10 to 1 (Table), the GM (μg/g creatinine) dropped from 0.45 to 0.03 (94% reduction; p=0.005) for pre-chelation lead and from 14.80 to 2.91 (80% reduction; p=0.04) for post-chelation lead. For pre and post-chelation cadmium, the corresponding figures were 0.34 to 0.12 (64% reduction; p=0.17) and 2.81 to 2.35 (16% reduction; p=0.48), respectively. Conclusions: TACT treatment may decrease total body burden of lead, further supporting lead is a modifiable CVD risk factor. Data are insufficient to inform on changes in the burden of cadmium or other metals. Ongoing, larger studies will assess the effect of repeated chelation on toxic metal burden and incident cardiovascular disease.

Using Inductively Coupled Plasma Mass Spectrometry to Assess Essential and Performance-Enhancing Metals in the Urine of Racehorses.

Recently, an increased tendency to use various metals has been observed in the sports competition fields. Many of these metals and their organic complexes reportedly have good pharmacologic, therapeutic and performance-enhancement uses; they are banned or recommended as controlled medications in competitive sports. The objective of this research was to determine the concentration of pharmacologically relevant metals in urine samples collected from racehorses at various sport events, develop a method and assess the concentrations of above metals using inductively coupled plasma mass spectrometry (ICP-MS). Seven alkali-alkaline earth metals (lithium, sodium, potassium, magnesium, calcium, strontium and barium) and six heavy metals (chromium, cobalt, copper, zinc, arsenic and selenium) were studied in detail. To compare and confirm the concentrations of these metals, the screening was carried out on the basis of region and sex of the animal. ICP-MS provides extremely high sensitivity that enables the determination of the metals at very low concentration from complex biological matrices. From the research, it is clear that irrespective of sex and region the concentration of metal is very high in some samples, might be accidental or intentional doping to improve sporting performances. This research work is of significant importance in setting threshold values for screening metals in race day samples in order to avoid potential harmful effects on athletes and the depth of malpractices, it can bring to sports.

Evaluation of heavy metals and metabolites in the urine of patients with breast cancer.

Epidemiologic studies demonstrated that the environment serves a crucial role in cancer development. Heavy metals, including arsenic (As), cadmium (cd), chromium (Cr), lead and mercury, are considered to be carcinogens or co-carcinogens. Furthermore, Cd has been detected in breast cancer (BC) tissue at high concentrations. The present study aimed to investigate the correlation between heavy metals detected in urine and urine metabolome of patients with BC, and their association with cancer development. Nuclear magnetic resonance was used to determine urine metabolites and an inductively coupled plasma mass spectrometry system was used to detect heavy metals in urine samples. The results demonstrated that Cd was markedly increased in the urine of patients with BC compared with the control population (approximately 2-fold). Cr and As were also increased in the urine of patients with BC. In addition, numerous small molecule metabolites were altered in the urine of patients with BC compared with the control population. This study also demonstrated that alterations in small molecule metabolites in the urine of patients with BC were very similar to results from a previous report. These findings indicated that environmental exposure to Cd, As, or Cr could influence the urine levels of metabolites, which may be involved in BC development. Further investigation is therefore required to examine a larger range of samples from different countries or areas in order to understand the impact of heavy metals on metabolism and BC development.

An integrated study of health, environmental and socioeconomic indicators in a mining-impacted community exposed to metal enrichment.

The occurrence of toxic metals and metalloids associated with mine tailings is a serious public health concern for communities living in mining areas. This work explores the relationship between metal occurrence (e.g., spatial distribution in street dusts), human health indicators (e.g., metals in urine samples, lifestyle and self-reported diseases) and socioeconomic status (SES) using Chañaral city (in northern Chile) as study site, where a copper mine tailing was disposed in the periurban area. This study model may shed light on the development of environmental and health surveillance plans on arid cities where legacy mining is a sustainability challenge. High concentrations of metals were found in street dust, with arsenic and copper concentrations of 24 ± 13 and 607 ± 911mg/kg, respectively. The arsenic concentration in street dust correlated with distance to the mine tailing (r = - 0.32, p-value = 0.009), suggesting that arsenic is dispersed from this source toward the city. Despite these high environmental concentrations, urinary levels of metals were low, while 90% of the population had concentrations of inorganic arsenic and its metabolites in urine below 33.2µg/L, copper was detected in few urine samples (< 6%). Our results detected statistically significant differences in environmental exposures across SES, but, surprisingly, there was no significant correlation between urinary levels of metals and SES. Despite this, future assessment and control strategies in follow-up research or surveillance programs should consider environmental and urinary concentrations and SES as indicators of environmental exposure to metals in mining communities.

Maternal Heavy Metal Exposure, Thyroid Hormones, and Birth Outcomes: A Prospective Cohort Study.

Maternal thyroid hormones during pregnancy play a critical role in fetal development. However, whether maternal heavy metal exposure affects their thyroid hormones and the effects on fetal growth are still unclear. To explore the effect of heavy metal exposure on maternal thyroid hormones and the potential mediation role of thyroid hormones on birth outcomes. Concentrations of heavy metals in urine samples and thyroid hormones in blood samples of 675 pregnant women were measured during early pregnancy in a cohort study conducted in China. Multivariable linear regressions were applied to explore the associations of maternal urinary heavy metal levels with both maternal thyroid hormones and birth outcomes. Mediation analyses were performed to assess the mediation role of thyroid hormones in these associations. Maternal urinary vanadium (V) exhibited an inverse association with free T3 (FT3) and FT3/free T4 (FT4) ratio levels. Urinary arsenic (As) and lead (Pb) had inverse relationships with FT3. We also observed the positive associations of maternal FT3 and FT3/FT4 ratio with birthweight. The mediation analyses suggested that 5.33% to 30.57% of the associations among V, As, and Pb levels and birth size might be mediated by maternal FT3 or FT3/FT4 ratio. We have shown that maternal exposures to V, As, and Pb at early pregnancy were associated with decreased maternal FT3 or FT3/FT4 ratio, which might contribute to reduced birthweight. Mediation analyses indicated that maternal thyroid hormone was a possible mediator of the association between urinary heavy metals and birth size.

Levels of heavy metals in urine samples of school children from selected industrial and non-industrial areas in Dar es Salaam, Tanzania.

The levels of lead, zinc, iron, copper and cadmium metals in the urine samples of selected school children in industrial and non-industrial areas in Dar es Salaam were investigated. Urine samples were collected from 120 children in industrial areas and 120 children in non-industrial areas then digested in concentrated acids and analysed using atomic absorption spectrophotometry (AAS). The concentrations of the heavy metals in the urine samples ranged from below detection limit/non-detectable (ND) to 1.92 mg/L for lead, ND to 2.55 mg/L for zinc, ND to 8.98 mg/L for iron and ND to 0.05 mg/L for copper. Cadmium was not detected. Significant differences were found between the concentrations of heavy metals in urine of pupils from the industrial areas and those from non-industrial areas. The mean concentrations of lead and copper in samples from industrial areas were significantly higher than those found in non-industrial areas (p < 0.002), while the mean concentrations of zinc and iron found in samples from non-industrial areas were significantly higher than those found in industrial areas (p < 0.0001). The contamination levels were generally high in samples from both areas indicating exposure from various sources. The findings indicate public health risks.

Analysis of persistent organic compounds and metals in urine samples of young adults (844.5)

Persistent organic compounds are known to cause chronic toxic effects in humans such as reproductive toxicity, neurotoxicity, and carcinogenesis. Epidemiological studies have reported correlation between these compounds and stress indicators and diseases. These toxicants include pesticides: aldrin, dieldrin, endrin, endosulfan, DDT and BPA; some of which are banned in the USA and some are of major concern to public health especially to young adults. We have investigated the presence of these toxicants along with heavy metals in the urine of young adults and correlated their levels to bilirubin. The protocol for this study was approved by the TSU Committee for the use of human subjects, consent of 21 participants (18‐35 years) was obtained and urine samples collected. HPLC was used to determine the levels of the toxicants, heavy metal levels were analyzed by ICP‐MS and bilirubin was by caffeine assay. HPLC analysis for pesticide shows a range of concentration for: aldrin 0.85 to 296 ppm, endoulfan 1 0.37 to 120 ppm, endrin 0 to 67.1 ppm, dieldrin 0 to 630 ppm and DDT 0 to 4.9 ppm; whle BPA 0 to 102.4 ppb. Metal analysis shows concentration for: Cr 0 to 1.415 ug/L, Ni 257 to 422 ng/L, AS 0 to 624 ng/L, Cd 0.02 to 1.995ug/L, Al 107 to 243.5 ng/L, and Pb 257 to 384 ng/L. Bilirubin level ranged from 157 to 1,387 ng/L. Correlation analysis was done for the levels of these organic compound with the levels of bilirubin, although some of the young adults high concentrations of these persistent organic compounds, we found only positive correlation between dieldrin and bilirubin. However, these concentrations are within the acceptable limit set by CDC and EPA.Grant Funding Source: NHLBI: HL03674 and HL070669.

Analysis of trace metals in single droplet of urine by laser ablation inductively coupled plasma mass spectrometry

Inductively coupled plasma mass spectrometry (ICP-MS) is now widely accepted as a universal and sensitive analytical technique in different research fields. In this project, we applied the technology to the analysis of complex matrix composition by using urine samples from Fabry disease patients and controls. The aims of the project were: (1) to develop a new and rapid analytical procedure for the determination of trace metal concentrations in single droplets of urine using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS); and (2) to establish preliminary results for trace metal concentrations in Fabry disease patient urine samples and controls. The processing of samples required only drying a homogeneous urine sample. Different supports (or sample substrates) were used: Teflon sheets, Whatman 903 filter paper, Urine Kid paper and glass slides. In order to establish the merits of the analytical method developed, matrix-matched synthetic laboratory standards spiked with analytes of interest were prepared at low concentrations (μg L −1 level). The precision and accuracy of the analytical method were <20% (LA-ICP-MS) for trace metals in 1 μL urine laboratory standards (at analyte concentrations of 300 ng mL −1). The limit of detection varied from 0.003 to 0.58 μg g −1 for lithium, boron, titanium, vanadium, chromium, manganese, cobalt, copper, zinc, arsenic, rubidium, strontium, molybdenum, silver, cadmium, barium, lead, and uranium. LA-ICP-MS allowed the quantification and comparison of different trace metals in urine samples from a Fabry disease patient and from a reference control individual. This method may be applicable to forensic science, particularly when only a small amount of dried urine sample is available for investigation.

Survey of urinary nickel in residents of areas with a high density of electroplating factories

The soil metal contamination arising from the discharge of the high density of electroplating factories in the geographic center of Taiwan has prompted concern about human exposure to harmful metals. This study aimed to determine the levels of nickel (Ni) in urine of residents living in the high vs. low factory-density areas, and to examine how these levels relate to gender and age. A total of 660 subjects, resident in the area for the last five years, were sampled according to the stratified random sampling approach, at ages 35–44, 45–54, and 55–64 years for both genders. Metals in urine samples were analyzed by inductively coupled plasma mass spectrometry (ICPMS). The geometric mean (95% confidence interval (CI)) of urinary Ni was 6.30 (5.99–6.62) μg/l. The 0.95 parametric reference interval (90% CI) of urinary Ni was estimated to be 1.74 (1.62–1.88) to 22.73 (21.14–24.44) μg/l. Subjects in the areas with a high density of electroplating factories had significantly higher urinary Ni levels than those in the low-density areas, but both types of areas had obviously higher urinary Ni levels when compared to the non-occupationally exposed population from western countries. The health significance of elevated urinary Ni and its causative factors remain to be determined.