Urinary Chromium Research Articles

Prenatal exposure to metal mixtures and lung function in children from the New Hampshire Birth Cohort Study

BACKGROUND AND AIM: Prenatal environmental exposure to metals and metalloids (referred to as “metals”) has been associated with childhood lung development, but limited data exist on metal mixtures. We aimed to investigate the association between gestational exposure to metal mixtures and childhood lung function among 267 maternal-child dyads from the New Hampshire Birth Cohort Study. METHODS: Maternal ~24-28-week gestational urinary arsenic speciation, aluminum, cadmium, cobalt, chromium, copper, iron, mercury, manganese, molybdenum, nickel, tin, lead, antimony, selenium, thallium, uranium, vanadium and zinc concentration were assessed using inductively coupled plasma mass spectroscopy (ICP-MS). Forced vital capacity (FVC), forced expiratory volume in the first second of exhalation (FEV1), and forced expiratory flow between 25% and 75% of FVC (FEF25-75) standardized z-scores were obtained at a median age of 7.4 years. We used quantile g-computation for each outcome and urinary metals adjusted for maternal smoking status, children’s age, sex and height. RESULTS:Urinary concentrations of cobalt, lead, nickel, cadmium, and chromium were inversely associated with lung function z-scores. Arsenic concentrations were inverse associated specifically with FVC and FEV1 z-scores. In contrast, lung function z-scores increased with vanadium, molybdenum, and thallium urine concentrations. CONCLUSIONS:Our findings suggest that prenatal exposure to metal mixtures impact lung function, with varying direction and magnitudes of effects. KEYWORDS: mixture, heavy metals, children’s environmental health, respiratory outcomes, biomarkers of exposure

Lead, cadmium, mercury, and chromium in urine and blood of children and adolescents in Germany - Human biomonitoring results of the German Environmental Survey 2014-2017 (GerES V).

Metals reach humans through food and drinking water intake and inhalation of airborne particles and can have detrimental health effects in particular for children. The metals presented here (lead, cadmium, chromium, and mercury) could lead to toxic effects such as neurotoxicity, mutagenicity, and have been classified as (possible) carcinogens. Using population representative data from the German Environmental Survey 2014-2017 (GerES V) from 3- to 17-year-old children on lead and cadmium in blood (n=720) and on cadmium, chromium, and mercury in urine (n=2250) we describe current internal exposure levels, and socio-demographic and substance-specific exposure determinants. Average internal exposure (geometric means) in blood was 9.47μg/L for lead and below 0.06μg/L (limit of quantification) for cadmium, and in urine 0.072μg/L for cadmium, 0.067μg/L for mercury, and 0.393μg/L for chromium, respectively. Younger children have higher concentrations of lead and chromium compared to 14-17-year-old adolescents, and boys have slightly higher mercury concentrations than girls. With respect to substance specific determinants, higher lead concentrations emerged in participants with domestic fuel and in non-smoking children with smokers in the household, higher levels of cadmium were associated with smoking and vegetarian diet and higher levels of mercury with the consumption of seafood and amalgam teeth fillings. No specific exposure determinants emerged for chromium. The health based guidance value HBM-I was not exceeded for mercury and for cadmium in urine it was exceeded by 0.6% of the study population. None of the exceedances was related to substantial tobacco smoke exposure. Comparisons to previous GerES cycles (GerES II, 1990-1992; GerES IV, 2003-2006) indicate continuously lower levels.

Systematic review of biomonitoring data on occupational exposure to hexavalent chromium.

Occupational exposure to hexavalent chromium (Cr(VI)) can cause serious adverse health effects such as lung cancer and irritation of the skin and airways. Although assessment of chromium (Cr) in urine is not specific for Cr(VI) exposure, the total amount of Cr in urine is the most used marker of exposure for biomonitoring of Cr(VI). The purpose of this systematic review was fourfold: (1) to assess current and recent biomonitoring levels in subjects occupationally exposed to Cr(VI), with a focus on urinary Cr levels at the end of a working week, (2) to identify variables influencing these biomonitoring levels, (3) to identify how urinary Cr levels correlate with other Cr(VI) exposure markers and (4) to identify gaps in the current research. To address these purposes, unpublished and published biomonitoring data were consulted: (i) unpublished biomonitoring data comprised urinary Cr levels (n=3799) of workers from different industries in Belgium collected during 1998-2018, in combination with expert scores indicating jobs with Cr exposure and (ii) published biomonitoring data was extracted by conducting a systematic literature review. A linear mixed effect model was applied on the unpublished biomonitoring data, showing a decreasing time trend of 30% in urinary Cr levels. Considering the observed decreasing time trend, only articles published between January 1, 2010 and September 30, 2020 were included in the systematic literature search to assess current and recent biomonitoring levels. Twenty-five studies focusing on human biomonitoring of exposure to Cr(VI) in occupational settings were included. Overall, the results showed a decreasing time trend in urinary Cr levels and the need for more specific Cr(VI) biomarkers. Furthermore, this review indicated the importance of improved working conditions, efficient use of personal protective equipment, better exposure control and increased risk awareness to reduce Cr levels in biological matrices. Further investigation of the contribution of the different exposure routes is needed, so that better guidance on the use of control measures can be provided. In addition, this review support the call for more harmonization of human biomonitoring.

Systemic inflammation mediates the association of heavy metal exposures with liver injury: A study in general Chinese urban adults

Heavy metal exposures have been reported to be associated with increased risk for liver injury. However, the potential mechanisms of the association remain unclear. A repeated-measure study of 9367 observations was conducted to quantify the associations of urinary heavy metals with serum alanine aminotransferase (ALT), a biomarker for liver injury, and assess the mediating role of systemic inflammation in such associations among general Chinese adults. In single-metal models, positive dose-response relationships between urinary vanadium (V), chromium (Cr), copper (Cu), arsenic (As), cadmium (Cd), tungsten (W), and lead (Pb) and serum ALT were observed. In the multiple-metal model containing the seven metals mentioned above, V and Cu remained positively associated with ALT. In longitudinal analyses of 3–6 years, each 1-unit increase in log-transformed levels of V and Cu was associated with an additional rate of annual ALT increase (95% CI) for 1.3% (0.7–1.8%) and 1.3% (0.7–2.0%), respectively. Plasma CRP concentrations were not only positively associated with urinary Cu and Cd, but also positively related with ALT. Furthermore, mediation analyses showed that CRP mediated 4.70% and 7.03% of urinary Cu- and Cd-associated ALT elevations. Our study provides clues for the prevention of heavy metal-induced liver injury.

Association of Heavy Metals with Overall Mortality in a Taiwanese Population.

Previous studies have shown links between heavy metals and many health issues. However, data on the association between heavy metals and mortality in the general population are still limited. Therefore, the aim of this study was to investigate the relationship between heavy metals and overall mortality in the general population. We enrolled 2497 participants (1001 males and 1496 females) living in southern Taiwan, and measured levels of seven heavy metals: lead (Pb) in blood and cadmium (Cd), nickel (Ni), copper (Cu), chromium (Cr), manganese (Mn) and arsenic (As) in urine. The median follow-up period was 41.8 (4–50) months, during which 40 (1.6%) patients died. Compared to the participants who survived, those who died had higher urine Cd, higher urine Cu and lower urine Mn levels. Multivariate analysis showed that high urine Cd (per 1 μg/L; hazard ratio [HR], 1.352; 95% confidence interval [CI], 1.089–1.680; p = 0.006), high urine Cu (per 1 μg/dL; HR, 1.350; 95% CI, 1.151–1.583; p < 0.001), and low urine Mn (per 1 μg/L; HR, 0.717; 95% CI, 0.557–0.923; p = 0.010) were associated with increased overall mortality. In conclusion, our results demonstrated that high levels of urine Cd and Cu and low urine Mn level were associated with increased overall mortality in the general population.

Increased urine chromium concentrations in a worker exposed to lead chromate due to medicinal herb intake

Background: Hexavalent chromium compounds are sensitizers of the skin and lung. Chronic exposure to hexavalent chromium compounds is associated with respiratory effects and ulceration and perforation of the nasal septum. Such compounds are also considered carcinogens of the lung and nasal and paranasal sinus. Objectives: To demonstrate the importance of studying occupational and non-occupational exposure when assessing the concentration of substances in the urine. Case study: A study was conducted of environmental chromium concentrations in the workplace. In addition, an occupational medical examination was performed, recording activities inside and outside the workplace, eating habits, blood lead and urine chromium at the beginning and end of the workday. Results: One worker exposed to lead chromate presented high chromium concentrations in urine (up to 62 µg/l before the working day and 52 µg/l at the end of the working day). Environmental chromium concentrations in the workplace were below 0.25 µg/m3. In view of the results, a full study was conducted of the patient’s habits outside work. He reported having bought a kilo of a medicinal herb infusion at a street market three weeks previously. The concentration of total chromium in the prepared infusion was 12000 µg/l. The patient stopped consuming the medicinal herb. Subsequently, the urine chromium analysis was below 0.5 µg/l. Discussion and Conclusions: This case is interesting because it demonstrates that the consumption of medicinal herbs can interfere with biological monitoring of workers exposed to hexavalent chromium compounds. This may give rise to confusion and can also create legal problems for companies and workers. It is important to provide advice to workers and to investigate their habits outside work, especially when there is a discrepancy between environmental and biological values. In this case, the increase in urinary chromium is due to the consumption of medicinal herbs.

Relationship between renal function and metal exposure of residents living near the No. 6 Naphtha Cracking Complex: A cross-sectional study

Heavy metals impair renal function, causing chronic kidney disease (CKD), and the petrochemical industry is one of the major environmental metal emission sources. This study aimed to investigate the relationship between renal function and metal exposure among the Taiwanese residents living near a petrochemical industry site. We recruited residents near the No. 6 Naphtha Cracking Complex, and they were categorized into a high-exposure (HE) group (N=190) in Taisi Village and a low-exposure (LE) group (N=1184) in other villages of Dacheng Township in Changhua County of Taiwan. The urinary nickel, chromium, and vanadium levels of the study subjects were measured and the levels were standardized by urine creatinine, and the estimated glomerular filtration rates (eGFRs) were calculated to estimate renal function by one-time health data. Linear regression models were applied to illustrate the correlations between the distance to the complex and urinary metal levels and renal function; linear and logistic regression models were applied to evaluate the associations between urinary metal levels and renal function indicators. The study subjects living closer to the petrochemical complex had significantly higher urinary nickel, chromium, and vanadium levels and worse renal function than study subjects living farther away. The urinary nickel and chromium levels of the study subjects were associated with their renal function indicators. When the subject's urinary nickel level increased 1-fold, the eGFR level significantly decreased by 0.820ml/min/1.73m2. Residents living closer to the petrochemical industry were exposed to higher metal levels and had worse renal function, and the nickel exposure of residents was potentially related to their decline in renal function.

THE RENAL FUNCTION STATUS OF METAL ELECTROPLATING WORKERS EXPOSED TO CHROMIUM VI

Chromium (Cr) is commonly used as an anti-corrosive agent. Due to its unique nature, Cr is used to coat metal in order to make it looks shiny and attractive. However, hexavalent chromium (Cr (VI)), a form of chromium used in electroplating, is classified as carcinogenic substance. Its portal of entry into the human body can be through inhalation, ingestion, and dermal absorption. Talang District in central-Java, Indonesia is a center of informal sector’s metal electroplating industry. Electroplating workers in the informal sector rarely wear personal protective equipment (PPE) while working. This research analyzed the relation between chromium exposure, age, length of employment, and nutritional status with renal function of metal electroplaters. The subjects of this study involved 35 electroplaters from Talang with working experience ranging between 6 and 40 years. The independent variables were age, length of employment, nutritional status and exposure to chromium. Dependent variable was workers’ renal function. Urine samples were collected to determine chromium exposure and renal function based on urinary chromium and creatinine levels. Data was analyzed using chi-square test with SPSS Statistics software. The average urinary chromium and creatinine levels were 21.16 μg/L and 209.75 mg/dL respectively. This study found no relation between age and chromium levels in urine and renal function. However, length of employment and nutritional status were found to be significantly related to renal function. Although chromium exposure does not appear significantly associate with renal function, the average urinary chromium levels of metal electroplaters did exceed threshold values.

Heavy metals in blood, milk and cow's urine reared in irrigated areas with wastewater

The aim of this work was to determine the content of lead (Pb), chromium (Cr), cadmium (Cd), arsenic (As), copper (Cu), strontium (Sr) and thallio (Tl) in blood, milk and urine from cows fed forage irrigated with sewage water and cultivated in the vicinity of the Popocatépetl volcano and determine the rate of transfer of these elements from blood to milk and urine. Digestion was performed in a microwave oven (CEM-MarsX). The determination was made using an ICP -OES. The Cd in the blood was significantly higher than in milk and urine. The Cr in the blood was higher than in the urine. In milk the content of Pb and Cu was significantly higher than in blood. Sr and Tl concentration in the urine was higher than that detected in milk and blood and Pb in blood. Milk transfer Index revealed a significant difference in relation to the TI values found in the urine and only in the case of Cu in milk was TI > 1. In urine, the values found of Sr and Tl were higher than milk TI. It is concluded that when metals are ingested by cows in fodder, they are easily transferred to milk and urine through the blood. Presence of heavy metals in the different matrices determines the degree of environmental and trofic chain contamination with which we can consider the cow a biomarker.

The Effect of Global DNA Methylation on PDCD5 Expression in the PBMC of Occupational Chromate Exposed Workers.

To evaluate the alteration of protein of programmed cell death 5 (PDCD5) in peripheral blood mononuclear cells (PBMC) and DNA methylation caused by hexavalent chromium exposure. There were 112 workers and 56 controls in this study. The chromium in RBC and urine, PBMC with PDCD5+, DNA methylation, urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and score of DNA damage were measured. In chromate exposed workers, the percent of PBMC with PDCD5+, urine 8-OHdG, and score of DNA damage were significantly higher, whereas global DNA methylation was significantly lower. The binary logistic regression and generalized linear mixed model analysis showed that the percent of PBMC with PDCD5+ was significantly associated with global DNA hypomethylation. The aberrant DNA hypomethylation plays an important role in PBMC apoptosis of occupational hexavalent chromium exposure.

Is Urinary Chromium Specific to Hexavalent Chromium Exposure in the Presence of Co-exposure to Other Chromium Compounds? A Biomonitoring Study in the Electroplating Industry.

Electroplating processes are widely used in metal industries to improve the resistance properties of manufactured metal parts. Workers in this industry are potentially exposed both to hexavalent chromium (Cr(VI)) and to other chromium compounds [mostly trivalent chromium (Cr(III))], due to the use of chromic acid baths. The goal of this study was to validate urinary chromium as a Cr(VI) exposure biomarker in the presence of exposure to other chromium compounds. A biomonitoring study consisted in monitoring airborne chromium exposure and urinary chromium for one working week in 93 workers from nine electroplating companies. Chromium concentrations were measured in all urinations of each volunteer for the working week. Individual airborne soluble and insoluble Cr(VI) as well as Cr(III) concentrations were measured for all of the shifts of the week. The main statistical analysis consisted in modelling, in a Bayesian framework, the pre- and post-shift urinary chromium as a function of airborne Cr(III) and airborne Cr(VI), taking into account the day of the week and the time of collection of the urines (pre- or post-shift). Preliminary descriptions showed an increase in pre-shift urinary chromium during the working week. The model showed an increase in urinary chromium over the shift related to the shift-specific airborne Cr(VI) concentration as well as an increasing trend over the week and a relationship with the mean weekly Cr(VI) thought to reflect chronic exposure. Taking into account the Cr(VI) exposure, there was no evidence of an effect of Cr(III) exposure on urinary chromium. A biological limit value (BLV) was derived from the French occupational exposure limit for Cr(VI) of 1 µg m-3 and was estimated at between 1.9 and 2.6 µg g-1 creatinine for a urinary sample collected at the end of the shift on the last working day of the week. In the present context of mixed exposure to Cr(III) and Cr(VI) in electroplating, this study showed that urinary chromium depended only on airborne Cr(VI) concentrations, which justifies using a BLV for assessing workers' exposure. The estimated BLV was close to the recommended French BLV, which is 1.8 µg g-1 creatinine, in the electroplating industry.

Metal Ion Release, Clinical and Radiological Outcomes in Large Diameter Metal-on-Metal Total Hip Arthroplasty at Long-Term Follow-Up.

Total hip arthroplasty (THA) with metal-on-metal (MoM) bearings have shown problems of biocompatibility linked to metal ion release at the local level causing an adverse reaction to metal debris (ARMD) and at a systemic level. The aim of this study was to evaluate clinical and radiological outcomes, and metal ion concentrations in the blood and urine of patients who underwent THA with the LIMA Met-Met hip system. Patients with ceramic-on-ceramic (CoC) bearings were included as a control group. In this study, 68 patients were enrolled: 34 with MoM THAs and 34 with CoC THAs. Patients were evaluated clinically (Harris Hip Score, SF-36) and radiologically at a median of 7.4 years after surgery. Whole blood and urinary cobalt and chromium levels were also assessed. Both types of implants were comparable in terms of clinical and functional results. Ion levels were significantly higher in the MoM group compared with CoC group 7 years after surgery. No correlations were found between metal ion levels and patient demographics, functional and radiological outcomes, and prosthesis features. Patient monitoring is thus advised to establish if prosthesis revision is necessary, especially in the case of MoM THA.

Biomonitoring of metals in inhabitants of Northern Chile: implications of surveillance in areas with historical exposures

Background: The presence of toxic metals in human populations is strongly associated with chronic diseases and should be monitored especially in communities with a history of chronic exposures as occurs in northern Chile.Objective: to establish concentrations and prevalence of exposure to metals in residents of the city of Antofagasta, Chile, and its main risk factors.Methods: a cross-sectional study in Antofagasta was made. The sample (1203 adults) had populational representability at the city level. Sociodemographic information, health status, and sources of exposure to metals were collected in the participants. Urinary Inorganic Arsenic (InAs), Cadmium (Cd), Chromium (Cr) and Mercury (Hg) levels, and Lead (Pb) in blood were measured using NIOSH methodology by Inductively coupled plasma atomic emission spectroscopy (ICP-AES).Results:The sample had an average age of 42.7 years, with an average residence time in the city of 30 years, predominantly women (54.5%), high smoking (51.5%), high occupation rate in mining activities (22.6%).Using cutoff used by the health authorities (35µg /L for urinary InAs, the prevalence was 8% in adults and 12.3% in children. However, 75% of the population has levels below 21.9 µg / L. The main factors associated with high levels of urinary inorganic arsenic in adults were sex (β= 3.12, IC 95% 0.2-6.05 for males) and low schooling (β= 7.1, IC 95% 0.4-14.6 in people having less 8 y of education). People residing more than 500 meters from fixed sources had higher InAs levels. Other metals are below risk levels defined by health authorities.Conclusions It is urgent that in this city all the sources related to InAs must be verified and develop social interventions and environmental health surveillance in order to reduce involuntarily exposure to this metalloid.

Associations of a Metal Mixture Measured in Multiple Biomarkers with IQ: Evidence from Italian Adolescents Living near Ferroalloy Industry.

Background:Research on the health effects of chemical mixtures has focused mainly on early life rather than adolescence, a potentially important developmental life stage.Objectives:We examined associations of a metal mixture with general cognition in a cross-sectional study of adolescents residing near ferromanganese industry, a source of airborne metals emissions.Methods:We measured manganese (Mn), lead (Pb), copper (Cu), and chromium (Cr) in hair, blood, urine, nails, and saliva from 635 Italian adolescents 10–14 years of age. Full-scale, verbal, and performance intelligence quotient (FSIQ, VIQ, PIQ) scores were assessed using the Wechsler Intelligence Scale for Children-III. Multivariable linear regression and Bayesian kernel machine regression (BKMR) were used to estimate associations of the metal mixture with IQ. In secondary analyses, we used BKMR’s hierarchical variable selection option to inform biomarker selection for Mn, Cu, and Cr.Results:Median metal concentrations were as follows: hair Mn, ; hair Cu, ; hair Cr, ; and blood Pb, . Adjusted models revealed an inverted U-shaped association between hair Cu and VIQ, consistent with Cu as an essential nutrient that is neurotoxic in excess. At low levels of hair Cu (10th percentile, ), higher concentrations (90th percentiles) of the mixture of Mn, Pb, and Cr (, , and , respectively) were associated with a 2.9 (95% CI: , )–point decrease in VIQ score, compared with median concentrations of the mixture. There was suggestive evidence of interaction between Mn and Cu. In secondary analyses, saliva Mn, hair Cu, and saliva Cr were selected as the biomarkers most strongly associated with VIQ score.Discussion:Higher adolescent levels of Mn, Pb, and Cr were associated with lower IQ scores, especially at low Cu levels. Findings also support further investigation into Cu as both beneficial and toxic for neurobehavioral outcomes. https://doi.org/10.1289/EHP6803

Associations of Heavy Metals with Metabolic Syndrome and Anthropometric Indices.

Previous studies have revealed associations between heavy metals and extensive health problems. However, the association between heavy metals and metabolic problems remains poorly defined. This study aims to investigate relationships between heavy metals and metabolic syndrome (MetS), lipid accumulation product (LAP), visceral adiposity index (VAI), and anthropometric indices, including body roundness index (BRI), conicity index (CI), body adiposity index (BAI), and abdominal volume index (AVI). We conducted a health survey of people living in southern Taiwan. Six heavy metals were measured: lead (Pb) in blood and nickel (Ni), chromium (Cr), manganese (Mn), arsenic (As), and copper (Cu) in urine. A total of 2444 participants (976 men and 1468 women) were enrolled. MetS was defined according to the Adult Treatment Panel III for Asians. Multivariable analysis showed that participants with high urine Ni (log per 1 μg/L; odds ratio (OR): 1.193; 95% confidence interval (CI): 1.019 to 1.397; p = 0.028) and high urine Cu (log per 1 μg/dL; OR: 3.317; 95% CI: 2.254 to 4.883; p < 0.001) concentrations were significantly associated with MetS. There was a significant trend of a stepwise increase in blood Pb and urine Ni, As, and Cu according to the number of MetS components (from 0 to 5, a linear p ≤ 0.002 for trend). For the determinants of indices, urine Cu was positively correlated with LAP, BRI, CI, and VAI; blood Pb was positively correlated with BRI, BAI, and AVI; urine Ni was positively correlated with LAP. High urine Cu and urine Ni levels were significantly associated with MetS, and there was a significant trend for stepwise increases in blood Pb and urine Ni, As, and Cu, accompanied by an increasing number of MetS components. Furthermore, several indices were positively correlated with urine Cu, urine Ni, and blood Pb.

Effects of Polybrominated Diphenyl Ethers on the Human Body Exposure in E-Waste Dismantling Region.

Objective To discuss the effects of polybrominated diphenyl ethers （PBDEs） exposure in e-waste dismantling region on the human body and provide data support for the identification of environmental health damage to residents in the e-waste dismantling region. Methods Adults in an e-waste dismantling region （exposed group, 54 participants） and a control region （control group, 58 participants） were selected, questionnaires were carried out and blood and urine samples were collected. Blood PBDEs, blood lipids, blood routine, blood lead, urine cadmium, urine chromium and urine nickel were detected. T-test was utilized to compare the differences of PBDEs between the two groups. Multivariate analysis were utilized to compare the differences between the two groups in blood routine indexes. Linear regression was used to analyze the relationship between PBDEs and blood routine. Results Exposure levels of PBDEs were significantly higher in the exposed group （240.00 ng/g, adjusted mass fraction of blood lipids, thereafter） than in the control group （93.00 ng/g, P<0.05）. There was no statistical significance in the differences in most blood routine indexes of the two groups （ P>0.05）, and their reference values were all within normal ranges. Mean platelet volume, plateletcrit, basophils percentage, absolute value of basophils, and mean corpuscular hemoglobin concentration were higher in the exposed group than in the control group （P<0.05）. Platelet distribution widths were lower in the exposed group than in the control group and below the normal reference range （P<0.05）. Conclusion PBDEs exposure in e-waste dismantling region tend to change platelet morphology, the number of basophils, and mean corpuscular hemoglobin concentration, and may pose potential health hazards to local residents.

The Effect of Chromium Exposure on Creatinine and Bun Level of Tanners in Leather Industry in Magetan

Chromium in the leather tanning industry can have an impact on workers� health. Kidney disease is often referred to as a side effect from exposure to chromium. Measurement of creatinine and BUN level is a method of examining kidney function. The purpose of this study was to analyze the effect of chromium exposure on creatinine and BUN level in leather tanning workers in small leather industry in Magetan. This type of research is observational with cross sectional design. The sample of the study was 13 exposed worker groups namely chromium operators and 13 unexposed groups namely administrative workers. The results showed that there were differences in the average levels of urine chromium in chromium operators and administrative workers (p-value = 0,000), there were differences in the average creatinine levels in chromium operators and administrative workers (p-value = 0,031), and there were no difference in the average level of BUN in chromium operators and administrative workers (p-value = 0,644). There were no influence of chromium levels in urine on the increase in creatinine levels (p-value = 0,189) and BUN (p-value = 0,854) in tanning workers, with a significance value of p-value> 0,05. The conclusion of this study had that chromium was no effect on creatinine and BUN levels. High levels of urine chromium in tanning workers indicate a health risk that requires control effort. Suggestion given is that the tanners need periodic health examination, keep personal hygiene before and after working as well as using Personal Protective Equipment (PPE). © INRA and Springer-Verlag France 2015.

Circulating differential miRNAs profiling and expression in hexavalent chromium exposed electroplating workers

Hexavalent chromium [Cr (Ⅵ)] has extensive applications in industries, and long-term occupational exposure to Cr (Ⅵ) may lead to lung carcinoma and other cancers. While microRNA (miRNA) can take part in carcinogenesis, little is known about its expression profile in the population with Cr (Ⅵ) exposure. Thus, this study aimed to explore miRNA expression profiles in Cr (Ⅵ) exposed workers and to identify the potential biological function of differentially expressed miRNAs. A total of 45 significant differentially expressed miRNAs were identified by the miRNA array. The results of validation showed that miR-19a-3p, miR-19b-3p, and miR-142-3p were downregulated and miR-590-3p and miR-941 were upregulated in the exposure group. Multivariate analysis demonstrated that age, exposure duration and urinary chromium level were associated with one or more miRNAs expression. Target gene analysis indicated that these miRNAs might participate in the regulation of DNA damage-related signaling pathways. Taken together, Cr (Ⅵ) exposure can result in differential expression of miRNAs in occupational workers, and the expression of these miRNAs is correlated with the level and duration of Cr (Ⅵ) exposure, and the differentially expressed miRNAs may participate in DNA damage response.

Assessment of Household and Outdoor Air Pollution Exposure Link to Urinary Metals Content in Pregnant Women

We aimed to estimate the association of urinary metal content with the exposure to hazardous household factors and ambient air pollution in pregnant women. We analyzed urine samples of 143 women enrolled at delivery and assessed household exposure by questionnaire. Air pollution estimates were based on monitoring stations and satellite-based models. Complaints about noise, rubbish, and sewage in the neighborhood were associated with higher uranium concentrations (prevalence ratio (PR) = 1.42, 1.46, and 1.18, respectively). Complaints about noise were more frequent in women with higher cobalt, nickel, molybdenum, cadmium, and vanadium urine concentrations (PRs = 2.42–9.43), and complaints about smell in women with higher cobalt and strontium (PRs = 2.55–6.27). Exposure to nitrogen oxides was associated with higher concentrations of nickel, aluminum, lead, and chromium in urine (PRs = 1.80–5.85). Women exposed to elevated levels of particulate matter were more likely to have higher concentrations of cobalt, nickel, thallium, lead, iron, strontium, barium, silver, and chromium (PRs = 1.97–13.64). Exposure to high levels of sulfur dioxide was positively associated with cobalt and nickel (PR = 1.98 and 1.88, respectively). The current analysis suggests the possibility of a related simultaneous exposure to multiple pollutants. Further studies are warranted to corroborate the findings and reveal the multiple exposure effect on human health.

Selenium, Zinc, Chromium, and Vanadium Levels in Serum, Hair, and Urine Samples of Obese Adults Assessed by Inductively Coupled Plasma Mass Spectrometry.

The objective of this study was to investigate of selenium (Se), zinc (Zn), chromium (Cr), and vanadium (V) levels in blood serum, hair, and urine of adult obese patients. A total of 199 lean and 196 obese subjects were enrolled in the study. Serum, hair, and urinary metal and metalloid analysis were performed by inductively coupled plasma mass spectrometry at NexION 300D (PerkinElmer Inc., USA). The results established that obese subjects were characterized by 47% and 30% lower serum Cr and V levels compared with controls, respectively, whereas serum Se levels exceeded control values by 9%. In contrast, hair Cr, Se, and V content in obese subjects exceeded the control values by 51%, 21%, and 50%, respectively. In turn, hair Zn levels were found to be significantly lower by 11% compared with the lean control values. In urine, the levels of V and Zn were found to be 30% and 18% higher in obese patients. Prevalence of hypertension in obese subjects was associated with a trend for impaired Se and Zn levels. In a regression model adjusted for age, gender, hypertension, atherosclerosis, and glucose intolerance, serum Cr, V, and hair Zn were inversely associated with body mass index (BMI), whereas hair Se was considered as the positive predictor. Our data allow proposing that the observed alterations may at least partially contribute to metabolic disturbances in obesity. In turn, monitoring of Se exposure in a well-nourished adult population is required to reduce its potential contribution to obesity.