Levels In Scalp Hair Research Articles

Long-Term Glucocorticoid Exposure and Incident Cardiovascular Diseases-The Lifelines Cohort.

Long-term glucocorticoid levels in scalp hair (HairGCs), including cortisol and the inactive form cortisone, represent the cumulative systemic exposure to glucocorticoids over months. HairGCs have repeatedly shown associations with cardiometabolic and immune parameters, but longitudinal data are lacking. We investigated 6341 hair samples of participants from the Lifelines cohort study for cortisol and cortisone levels and associated these to incident cardiovascular diseases (CVD) during 5 to 7 years of follow-up. We computed the odds ratio (OR) of HairGC levels for incident CVD via logistic regression, adjusting for classical cardiovascular risk factors, and performed a sensitivity analysis in subcohorts of participants < 60 years and ≥ 60 years of age. We also associated HairGC levels to immune parameters (total leukocytes and subtypes). Hair cortisone levels (available in n = 4701) were independently associated with incident CVD (P < .001), particularly in younger individuals (multivariate-adjusted OR 4.21, 95% CI 1.91-9.07 per point increase in 10-log cortisone concentration [pg/mg], P < .001). All immune parameters except eosinophils were associated with hair cortisone (all multivariate-adjusted P < .05). In this large, prospective cohort study, we found that long-term cortisone levels, measured in scalp hair, represent a relevant and significant predictor for future CVD in younger individuals. These results highlight glucocorticoid action as possible treatment target for CVD prevention, where hair glucocorticoid measurements could help identify individuals that may benefit from such treatments.

Hair cortisol, glucocorticoid gene receptor polymorphisms, stress, and testicular function

ObjectiveSelf-reported psychological stress has been associated with decreased semen quality. Cortisol levels in scalp hair (hair cortisol concentration, HCC) has emerged as a potential objective marker of psychological stress. Thus, we investigated if HCC was associated with markers of testicular function. Furthermore, we examined whether three common single nucleotide polymorphisms in the glucocorticoid-receptor gene (NR3C1, chromosome 5), potentially affecting receptor sensitivity, were associated with HCC and could influence the studied association between HCC and testicular function. DesignCross-sectional study. MethodsWe analysed HCC, serum-levels of reproductive hormones, semen parameters, and the three NR3C1-polymorphisms; BclI (rs41423247), Tth111I (rs10052957), and 9β (rs6198), in a population of 696 men from the general population. ResultsHCC was not associated with testicular function, and adjustment for the three NR3C1-polymorphisms did not alter the results. However, HCC increased significantly with the number of Tth111I minor-alleles (T) and decreased significantly with the number of 9β minor-alleles (G). ConclusionGiven previously shown associations between stress and semen quality, and that no association between HCC and self-reported stress was observed in the current study, we speculate that negative reproductive effects of stress may not be mediated directly by cortisol. This study demonstrates associations between HCC and glucocorticoid receptor gene variants indicating that these SNPs may influence systemic glucocorticoid levels, but the potential health effects of such alterations are yet unknown.

The Relation Between Cortisol and Anthropometric Measurements Throughout Lifespan: A Systematic Review and Meta-Analysis

Introduction: Recently, cross-sectional studies report associations between long-term glucocorticoid levels in scalp hair (HairGC) and obesity. However, there is a wide variation in studied outcomes and associations, possibly caused by differences in population characteristics, e.g. age, sex, dispersion of adiposity, and used laboratory methods. The aim of this systematic review and meta-analysis was to investigate the relation between HairGC and anthropometrics and to explore possible moderators of this association. Methods: We searched the Medline, Embase, Cochrane, Web of Science, Scopus, Cinahl, PsycInfo, and Google Scholar databases for articles that relate HairGC to measures of adiposity (date 11-16-2020). Primary outcomes were correlations between hair cortisol (HairF) and cortisone (HairE), and anthropometrics: BMI, waist circumference (WC) and waist-hip-ratio (WHR). Authors were contacted to provide missing outcome information. Pooled correlation coefficients were calculated using random effects models. Assessment of heterogeneity was performed using the I2 statistic. Exploratory moderator analyses were performed with subgroup analyses and meta-regression. This systematic review was performed in accordance to the PRISMA guidelines. Results: Our systematic search identified 150 cohorts, comprising a total of 37,107 unique individuals, of which 15,033 sampled from population-based cohorts. For BMI, the pooled correlation for HairF was 0.121 (95% CI 0.083–0.158, n=26,941; I2 94.2%, p<0.001) and for HairE 0.108 (95% CI 0.047–0.167, n=7,250; I2 52%, p<0.01). For WC, the pooled correlation for HairF was 0.111 (95% CI 0.058–0.164, n=10,290; I2 63%, p<0.01) and for HairE 0.200 (95% CI 0.137–0.264, n=2,198; I2 0%, p=0.42). For WHR, the pooled correlation for HairF was 0.102 (95% CI 0.040–0.163, n=6,865; I2 27%, p=0.14) and for HairE 0.261 (95% CI 0.195–0.330, n=1,314; I2 0%, p=0.40). A higher percentage of male participants was related to stronger correlations with WC (p<0.001), but not with BMI and WHR. Mean age, mean BMI, and mean HairGC levels of the cohorts did not significantly moderate the pooled correlations, neither did the used laboratory techniques (immunoassays vs mass spectrometry-based assays). Conclusion: This unique, large meta-analysis demonstrates that long-term endogenous glucocorticoids as assessed by HairGC show small but consistent correlations to measures of obesity, despite a large heterogeneity between the included cohorts. The strongest associations were found between HairE and WC and between HairE and WHR. This suggests that glucocorticoid levels in the high-normal range, especially cortisone, may contribute to or reflect the state of specifically central adiposity, even within the general population.

Method validation of measuring endogenous lead levels in scalp hair of acid battery plant workers by flame atomic absorption spectroscopy

ABSTRACT Acid battery plants cause high emissions of lead which is considered a harmful contaminant for human health. Since lead is found in measurable amounts in scalp hair of acid battery workers, flame atomic absorption spectroscopy is considered a satisfactory tool for measuring endogenous lead levels in scalp hair. The method used in sample preparation was wet ashing with nitric acid (69–71%). The method validation comprises the study of selectivity, linearity, recovery, limit of detection, the limit of quantification, accuracy, intra-day precision, and inter-day precision. The value of correlation coefficient was 0.9992. The limit of detection and the limit of quantification were 0.254 and 0.570 mg/g, respectively. The relative recovery % value was between 4.3% and 13%. In addition, the value of intra-day precision was 2.85% and 4.63%, at 0.50 mg/g and 2.0 mg/g spiked hair samples, while the inter-day precision was found 7.41% and 4.38% at 0.50 mg/g and 2.0 mg/g spiked hair samples. In conclusion, this flame atomic absorption spectroscopy validated method meets the validation requirements in selectivity, linearity, accuracy, and precision and it was successfully applied for determination of lead in scalp hair.

Earwax: an innovative tool for assessment of tobacco use or exposure. A pilot study in young adults

The present work represents a novel approach using earwax (cerumen) for the evaluation of the smoking status with regards to tobacco use/exposure. The method utilizes the difference in the concentration profiles of nicotine and its related compounds in earwax to discriminate among non-, passive, and active smokers. Earwax samples were collected from three study groups (non-, passive, and active smokers) and subjected to analysis by headspace gas chromatography–mass spectrometry. The nicotine levels in earwax were much lower than cotinine levels, even for active smokers; however, it was reported that the nicotine levels in scalp hair were much higher than the cotinine levels. Therefore, it is obviously correct that earwax is protected from external contamination to a larger extent than expected. The concentration profiles of nicotine and its related compounds (o-nicotine, cotinine, and anabasine) in the analyzed earwax samples were treated by data mining techniques. It was possible to discriminate the studied groups using the evolutionary tree (evtree) algorithm and support vector machine discriminant analysis as the statistical models with the best discrimination accuracies of 96.7 and 95.0%, respectively. The analytical method applied requires no sample pretreatment which makes it easy, fast, and a low-cost alternative method to those employing other biological matrices, such as blood, urine, and hair. The earwax, which is considered a neglected body secretion, is a useful tool to determine the exposure to tobacco smoke noninvasively and without the influence of external contamination.

Hair Trace Element and Electrolyte Content in Women with Natural and In Vitro Fertilization-Induced Pregnancy.

The objective of the present study was to perform comparative analysis of hair trace element content in women with natural and in vitro fertilization (IVF)-induced pregnancy. Hair trace element content in 33 women with IVF-induced pregnancy and 99 age- and body mass index-matched control pregnant women (natural pregnancy) was assessed using inductively coupled plasma mass spectrometry. The results demonstrated that IVF-pregnant women are characterized by significantly lower hair levels of Cu, Fe, Si, Zn, Ca, Mg, and Ba at p<0.05 or lower. Comparison of the individual levels with the national reference values demonstrated higher incidence of Fe and Cu deficiency in IVF-pregnant women in comparison to that of the controls. IVF pregnancy was also associated with higher hair As levels (p<0.05). Multiple regression analysis revealed a significant interrelation between IVF pregnancy and hair Cu, Fe, Si, and As content. Hair Cu levels were also influenced by vitamin/mineral supplementation and the number of pregnancies, whereas hair Zn content was dependent on prepregnancy anthropometric parameters. In turn, planning of pregnancy had a significant impact on Mg levels in scalp hair. Generally, the obtained data demonstrate an elevated risk of copper, iron, zinc, calcium, and magnesium deficiency and arsenic overload in women with IVF-induced pregnancy. The obtained data indicate the necessity of regular monitoring of micronutrient status in IVF-pregnant women in order to prevent potential deleterious effects of altered mineral homeostasis.

Trace Element Levels in Scalp Hair of School Children in Shigatse, Tibet, an Endemic Area for Kaschin-Beck Disease (KBD).

Kaschin-Beck disease (KBD) is an endemic osteoarthritis, and the etiology is closely related with levels of trace elements in the human body. Currently, it is clear that the selenium (Se) status of children in KBD areas is lower than that in non-KBD areas in the Tibetan Plateau, whereas role of other elements are yet unknown. This study aimed to assess some essential trace elements (Se, Mo, Mn, Zn, Fe, Cu, Co, and Sr) in children using scalp hair as a biomarker, and 157 samples from school children aged 8-14years old were collected from both KBD and non-KBD areas in Shigatse, Tibet. Se and Mo were measured by inductive coupled plasma mass spectrometry, and the other elements were determined by inductive coupled plasma optical emission spectrometry. Compared with the non-KBD areas, Se, Mo, Mn, Fe, Zn, Co, and Sr levels of children in KBD areas were found to be significantly different (P<0.05); while in linear discriminant analysis, only Se and Zn were found to contribute to the KBD prevalence in the study area. The hair Se level of children in KBD areas ranged from 0.115 to 0.299mg/kg, while in non-KBD areas it ranged from 0.135 to 0.519mg/kg. The Zn content of children's hair was between 83 and 207mg/kg in KBD areas, while it was 37 and 219mg/kg in non-KBD areas. Lower Se and higher Zn levels in children in KBD areas was found when compared with non-KBD groups. In addition, Mo levels were found to be different between KBD areas and non-KBD areas on the opposite side of the Yarlung Zangbo River, but no close relationship was shown because there was no difference compared with the non-KBD area on the same side of the river. Our observations suggest that Se deficiency is still an important factor for the occurrence and prevalence of KBD, while the relationship between Zn and KBD needs to be further explored in the Tibetan Plateau.

Long-term glucocorticoid concentrations as a risk factor for childhood obesity and adverse body-fat distribution.

Childhood obesity is an important risk factor for premature development of the metabolic syndrome (MetS) at adulthood. There is need for understanding of the mechanisms underlying the MetS and obesity. Patients with Cushing's disease suffer from similar metabolic complications, leading to the hypothesis that inter-individual cortisol variation may contribute to the onset of obesity. In addition, glucocorticoid receptor (GR)-gene polymorphisms resulting in differential glucocorticoid (GC) sensitivity, have been associated with an adverse metabolic profile. To study associations of GC levels in scalp hair, as a marker of long-term systemic GC concentrations, and genetically determined GC sensitivity with obesity and body-fat distribution in children. We performed a cross-sectional study of cortisol and cortisone concentrations over a 3-month period, measured by LC-MS/MS (Liquid Chromatography Tandem Mass Spectrometry) in hair of 3019 6-year-old children participating in the Generation R study. Genotyping of GR-gene polymorphisms was performed. Of all children, 4.3% was obese and 13.4% overweight. Cortisol was significantly associated with risk of obesity (odd ratio (OR): 9.4 (3.3-26.9)) and overweight (OR: 1.4 (1.0-2.0)). Cortisone was associated with risk of obesity (OR: 1.9 (1.0-3.5)). Cortisol and cortisone were significantly positively associated with body mass index, fat mass (FM) index and android/gynecoid FM ratio. GR polymorphisms were not associated with adiposity parameters. Long-term cortisol concentrations are strongly associated with an increased risk of childhood obesity and adverse body-fat distribution. Future research may reveal whether these are causal relations and may be a target for therapy.

The relation between long‐term cortisol levels and the metabolic syndrome in HIV‐infected patients

Patients infected with the human immunodeficiency virus (HIV) have an increased risk of metabolic complications such as dyslipidaemia, insulin resistance and hypertension; symptoms that are also associated with an excess of the hormone cortisol. We studied the relationship between long-term cortisol levels and metabolic syndrome (MetS) in HIV-infected patients. Cross-sectional study performed at the outpatient clinic of infectious diseases of the Erasmus MC, University Medical Center Rotterdam, the Netherlands. Fasting blood samples and anthropometric data were collected in 126 HIV-infected patients. An ELISA-based technique was used to determine long-term cortisol levels in scalp hair. Cortisol levels were compared to 191 healthy controls. A higher risk of MetS was observed in HIV patients with a low hair cortisol (odds ratio lower vs upper tertile 4·23, P=0·04). Hair cortisol levels were not significantly different between HIV patients and healthy controls (16·4pg/mg vs 13·5pg/mg; P=0·14). The risk of MetS was significantly higher in HIV-infected patients in the lowest hair cortisol group compared with patients in the highest hair cortisol group. This finding contrasts with results from studies in uninfected individuals where a high cortisol level in hair is associated with metabolic syndrome. The results of this study suggest that these metabolic complications might be related to relative cortisol hypersensitivity in HIV patients.

Trace elements in scalp hair samples from patients with relapsing-remitting multiple sclerosis.

BackgroundEpidemiological studies have suggested a possible role of trace elements (TE) in the etiology of several neurological diseases including Multiple Sclerosis (MS). Hair analysis provides an easy tool to quantify TE in human subjects, including patients with neurodegenerative diseases.ObjectiveTo compare TE levels in scalp hair from patients with MS and healthy controls from the same geographic area (Sicily).MethodsICP-MS was used to determine the concentrations of 21 elements (Ag, Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sr, U, V and Zn) in scalp hair of 48 patients with relapsing–remitting Multiple Sclerosis compared with 51 healthy controls.ResultsMS patients showed a significantly lower hair concentration of aluminum and rubidium (median values: Al = 3.76 μg/g vs. 4.49 μg/g and Rb = 0.007 μg/g vs. 0.01 μg/g;) and higher hair concentration of U (median values U: 0.014 μg/g vs. 0.007 μg/g) compared to healthy controls. The percentages of MS patients showing hair elemental concentrations greater than the 95th percentile of controls were 20% for Ni, 19% for Ba and U, and 15% for Ag, Mo and Se. Conversely, the percentages of MS patients showing hair elemental concentrations lower than the 5th percentile of healthy controls were 27% for Al, 25% for Rb, 22% for Ag, 19% for Fe, and 16% for Pb. No significant association was found between levels of each TE and age, disease duration or Expanded Disability Status Scale (EDSS) score. After stratification by gender, healthy subjects did not show any significant difference in trace element levels, while MS patients showed significant differences (p<0.01) for the concentrations of Ag, Cr, Fe, Ni and Sr. No significant differences were also found, at p<0.01, in relation to the use of cigarettes, consume of water, vegetables and place of living.ConclusionThe different distributions of TE in hair of MS patients compared to controls provides an additional indirect evidence of metabolic imbalance of chemical elements in the pathogenesis of this disease. The increase in U and decrease in Al and Rb levels in MS compared to controls require further assessments as well as the observed different distributions of other elements.

Cortisol levels in scalp hair of patients with structural heart disease

BackgroundStress is considered a modifiable risk factor for cardiovascular disease. Scalp hair analysis is a tool to assess long-term exposure to the stress hormone cortisol. We aimed to determine the association between hair cortisol concentrations (HCC) and clinical characteristics in patients with structural heart disease. Additionally, we investigated potential predictors for longitudinal change in HCC. MethodsThe study consisted of 261 patients with structural heart disease from a randomized controlled trial of mindfulness training. One sample of scalp hair was used to determine HCC both at baseline and at 12-week follow-up. In 151 patients, HCC was available (mean age: 41.3years, range 18–65). We investigated the association between HCC at baseline and several physiological measures (BMI, blood pressure, heart rate, respiratory rate, 6-minute walk test), as well as psychological parameters (physical and mental component summary measures (SF-36), emotional distress (HADS), and perceived stress). Additionally, we used these clinical parameters to predict HCC change over time. ResultsThe median HCC was 22.3pg/mg of hair (23.5 interquartile range). In multivariable linear regression analyses, an association was observed between log-transformed HCC and BMI (β 0.171, p=0.037), respiratory rate (β 0.194, p=0.016), and the physical summary score (β −0.163, p=0.054). Independent predictors of log-transformed HCC change after 12weeks were mental summary score (β −0.200, p=0.019) and diastolic blood pressure (β −0.171, p=0.049). ConclusionsIn patients with structural heart disease a positive association exists between HCC and BMI. Mental health status may predict a change in long-term cortisol over time.

Trace elements in scalp hair and fingernails as biomarkers in clinical studies

Context: There are accumulating evidences that the metabolism of several trace elements might have specific roles in clinical disorders and the pathogenesis of many diseases, such as diabetes mellitus (DM) and hypertension (HT). Objectives: To validate the analytical procedure and compare the levels of Cd, Cr, Cu, Pb, and Zn in scalp hair (SH) and fingernails (FN) of patients. Furthermore, to prove that human tissues such as hair and nails are useful in the studies pertaining to chronic body exposure and good biomarkers in clinical studies. Setting and Design: Inductively coupled plasma optical emission spectroscopy operating conditions were carefully selected and well-optimised in order to maximise the sensitivity for the desired elements and to obtain the best precision and accuracy. Factors affecting analytical and biological variability of the concentrations under study were discussed and carefully optimised. Materials and Methods: Totally, 160 samples of SH and 130 FN were collected from occupants of urban population from different districts adjacent to Taif city, Kingdom of Saudi Arabia. Different analytical procedures were investigated, and the most reliable one was developed and validated. Method Validity: The validity of the method was checked by standard addition method. The recoveries were in the range of 96.2-105.7%. Results: Cd, Cr, Cu, and Pb levels in SH were significantly higher in DM and HT compared to control groups, whereas, Zn was significantly lower. Cd and Pb levels in FN were significantly higher in DM and HT, whereas, Cr and Zn were lower, and Cu was in the same levels as compared to the control group. Conclusion: These findings may be consistent with those obtained in other studies, confirming that the deficiency and efficiency of trace elements play a role in clinical disorders and the pathogenesis of many diseases.

Determination of Selected Heavy Metal Levels in Scalp Hair and Fingernail Samples from Dental Laboratory Technicians

The aim of this study was to determine selected heavy metal levels including cobalt (Co), Chromium (Cr) nickel (Ni) in scalp hair and fingernail samples of dental technicians. The scalp hair and fingernail samples were collected from 55 dental technicians and 25 medical technicians (control group). In the same time a questionnaire was filled by each subject of the two groups. The concentration of heavy metals (Co, Cr and Ni) in scalp hair and fingernail were determined by spectrometry. The result showed that the Co concentration in hair and nails of dental technicians was (0.74 μg/g, 6.5 μg/g respectively) compared with medical technicians (0.04 μg/g, 0.03 μg/g respectively). Ni concentration in hair and nails of dental technicians was (12.00 μg/g, 17.4 μg/g respectively) compared with medical technicians (6.3 μg/g, 6.00 μg/g respectively). Concentration of Cr in hair and nails of dental technicians was (9.37 μg/g, 10.6 μg/g respectively) compared with medical technicians (0.0 μg/g, 10.3 μg/g respectively), Ni was found to have the highest level in the hair and fingernails of dental technicians.

Exposure of lead to mothers and their new born infants, residents of industrial and domestic areas of Pakistan

Prenatal and early-life exposure to lead (Pb) is hypothesized to have adverse effects on childhood health. The aim of this study was to evaluate the prenatal exposure to Pb and its adverse effects on mothers and their infants who are residents of industrial (exposed) and domestic areas (referents) in Karachi, Pakistan. The biological samples (scalp hair and blood) of mother-infants pairs were analyzed for Pb levels by atomic absorption spectrometry after microwave-assisted acid digestion method. The Pb levels in scalp hair and blood samples of exposed mothers were found in the range of 7.52-8.70 μg/g and 115-270 μg/L, respectively, which were significantly higher than those values obtained for referent mothers (p < 0.001). The Pb levels in the blood (umbilical cord) and hair of neonates of exposed mother that were found in the range of 83-178 μg/L and 4.95-7.23 μg/g, respectively, were significantly higher than the obtained values of referent neonates (p > 0.001). The correlation between maternal and cord blood of both groups was found in the range of 0.708-0.724 (p < 0.01). It was observed that there were higher Pb burdens in exposed mothers and their infants as compared to referent mothers-neonates.

Potentially harmful elements (PHEs) in scalp hair, soil and metallurgical wastes in Mitrovica, Kosovo: The role of oral bioaccessibility and mineralogy in human PHE exposure

Internationally publicized impacts upon human health associated with potentially harmful element (PHE) exposure have been reported amongst internally displaced populations (IDPs) in Mitrovica, Kosovo, following the Kosovan War. Particular concern has surrounded the exposure to Pb indicated by the presence of highly elevated concentrations of Pb in blood and hair samples. This study utilizes a physiologically-based in-vitro extraction method to assess the bioaccessibility of PHEs in surface soils and metallurgical waste in Mitrovica and assesses the potential daily intake of soil-bound PHEs. Maximum As (210mgkg−1), Cd (38mgkg−1), Cu (410mgkg−1), Pb (18790mgkg−1) and Zn (8500mgkg−1) concentrations in surface soils (0–10cm) are elevated above guideline values. Samples with high PHE concentrations (e.g. As >1000mgkg−1; Pb >1500mgkg−1) exhibit a wide range of bioaccessibilities (5.40 – 92.20% in the gastric (G) phase and 10.00 – 55.80% in the gastric–intestinal (G–I) phase). Samples associated with lower bioaccessibilities typically contain a number of XRD-identifiable primary and secondary mineral phases, particularly As- and Pb-bearing arsenian pyrite, beudantite, galena and cerrusite. Quantification of the potential human exposure risk associated with the ingestion of soil-associated PHEs indicates that on average, 0.01μg Cd kg−1 BW d−1, 0.16μg Cu kg−1 BW d−-1, 0.12μg As kg−1 BW d−1, 7.81μg Pb kg−1 BW d−1, and 2.68μg Zn kg−1 BW d−1 could be bioaccessible following ingestion of PHE-rich soils in the Mitrovica region, with Pb, and to a lesser extent As, indicating the likely possibility of local populations exceeding the recommended tolerable daily intake. Lead present within surface soils of the area could indeed have contributed to the human Pb burden due to the high bioaccessibility of Pb present within these soils (13.40 – 92.20% in the gastric phase). Data for Pb levels in scalp hair (≤120μgg−1) and blood (≥650μgdL−1; WHO, 2004) for children that have lived within IDP camps in Mitrovica indicate significant Pb uptake has indeed taken place. The highly bioaccessible nature of soil-associated PHEs in this study highlights the need for appropriate environmental management approaches that limit the exposure of local populations to these contaminated soils.

Effects of occupational environmental controls and work management on chromosomal damage in dental technicians in Japan

Dental technicians use various materials, particularly metal alloys and monomers and polymers based on methylmethacrylate. Environmental hygiene issues surrounding the work of dental technicians have been recognized. Despite the need for observance of occupational environmental controls and work management, compliance among dental laboratories appears to be low. We evaluated the relationship between genotoxic effects in dental technicians and occupational environmental controls and work management. We used cytokinesis-blocked micronuclei (CB-MN) frequencies in peripheral lymphocytes and metal levels in scalp hair. We also assessed nutritional factors related to anti-genotoxic effects using a self-administered brief diet history questionnaire. Study subjects were 54 male dental technicians and 38 male clerical workers. The parameters on the micronuclei (MN) frequency in dental technicians and clerical workers were analyzed by forward stepwise multiple regression analyses. Age (P < 0.01, β = 0.561), occupation as a dental technician (P < 0.01, β = 0.636) and aluminum levels in scalp hair (P < 0.05, β = 0.213) were risk factors that significantly increased MN frequency. The significant parameters on the MN frequency in dental technicians were observance of hand-washing as work management (P < 0.01, β = -0.304), work period (P < 0.01, β = 0.509), germanium levels in scalp hair (P < 0.01, β = -0.314) and workplace (P < 0.05, β = 0.235). To avoid genotoxic effects, observance of occupational environmental controls and work management is necessary for dental technicians.

Shift Work at Young Age Is Associated with Elevated Long-Term Cortisol Levels and Body Mass Index

The incidence of obesity and other features of the metabolic syndrome is increased in shift workers. This may be due to a misalignment between the internal circadian rhythm and the behavioral rhythm. The stress hormone cortisol could play a role in this phenomenon because it is secreted in a circadian rhythm, and long-term elevated cortisol leads to components of the metabolic syndrome. We compared cortisol levels in scalp hair of shift and day workers to study changes in long-term cortisol due to shift work. Hair samples were collected from 33 shift workers and 89 day workers. Cortisol was extracted from the hair samples with methanol, and cortisol levels were measured using ELISA. Height and weight were measured, and body mass index (BMI) was calculated. Shift workers had higher hair cortisol levels than day workers: 47.32 pg/mg hair [95% confidence interval (CI) = 38.37-58.21] vs. 29.72 pg/mg hair (95% CI = 26.18-33.73) (P < 0.001). When divided in age groups based on the median age, elevated cortisol levels were present only in younger shift workers: 48.53 pg/mg hair (95% CI = 36.56-64.29) vs. 26.42 pg/mg hair (95% CI = 22.91-30.55) (P < 0.001). BMI was increased in younger shift workers as well: 27.2 (95% CI = 25.5-28.8) vs. 23.7 (95% CI = 22.8-24.7) in young day workers (P = 0.001). Hair cortisol and BMI were positively correlated (β = 0.262; P = 0.005). Shift work at a young adult age is associated with elevated long-term cortisol levels and increased BMI. Elevated cortisol levels and BMI may contribute to the increased cardiovascular risk found in shift workers.

Correlation Between Arsenic Concentration in Fish and Human Scalp Hair of People Living in Arsenic-Contaminated and Noncontaminated Areas of Pakistan

The effects of arsenic (As) toxicity due to frequent consumption of arsenic-contaminated fish was estimated by the analysis of scalp hair of adult males, living near arsenic-contaminated area of Pakistan. For comparison purposes, scalp hair samples were also collected from the inhabitants of Hyderabad city consuming fish species with low levels of As, collected from Indus River. Concentration of As in scalp hair samples was analyzed by using hydride generation atomic absorption spectrometry (HG AAS), after microwave-assisted acid digestion. The accuracy of the As measurement was tested simultaneously analyzing certified reference material. The concentration of As in muscle tissues of fish species were found in the range of 2.11 to 14.1μg/g and 1.92 to 12.2μg/g, collected from arsenic-contaminated and noncontaminated areas, respectively. Exposed subjects had significantly elevated levels of As in scalp hair samples (0.72-4.94μg/g) as compared with referent subjects (0.21-1.484μg/g; p < 0.01). The As levels in scalp hair was positively correlated with As levels in fish.

Co and Cr accumulation in hair after metal-on-metal hip resurfacing arthroplasty

Currently, it is unclear whether Co and Cr levels are persistently elevated in the body after hip resurfacing arthroplasty (HRA). This study aimed to evaluate Co and Cr levels in the body after HRA using hair as samples. Among 22 patients who had metal-on-metal HRA(m-o-m group) using the DePuy ASR system, scalp hair of 1.5 cm in length and 2 g in weight was collected before and at 6 and 12 months after surgery. Inductively coupled plasma-mass spectrometry (ICP-MS) was used to detect Co and Cr levels in the scalp hair. Another 22 patients with total hip replacements were randomly selected from a similar age range as controls (m-o-p group). Metal levels in hair were detected with multiple measurements and analysed by repeated measures analysis of variance. Both Co and Cr levels were significantly increased in the m-o-m group after surgery compared with those in the m-o-p group (P < 0.01). Co levels at 6 months post-operatively were 12-fold those before surgery, and Co levels 12 months postoperatively were lower than those at 6 months, but this difference was not significant (P = 0.0805) between the two time points in the m-o-m group. Cr levels were persistently elevated after surgery and were increased by 10-fold compared with those at baseline in the m-o-m group. Co and Cr levels in scalp hair are ideal indicators for metal levels in the body after HRA. Co and Cr levels in the body were greatly increased after metal-on-metal HRA. Long-term accumulation of these metals needs to be further investigated

Determination of Arsenic in Scalp Hair of Children and its Correlation with Drinking Water in Exposed Areas of Sindh Pakistan

This study was focused on the analysis of arsenic (As) levels in scalp hair of children (age, <10 years) collected from two towns of Khairpur, Pakistan, to evaluate the effects of As-contaminated groundwater. For comparative purposes, scalp hair samples of children were also collected from that area having low levels of As (<10 μg/L) in drinking water. Groundwater and scalp hair samples of children were collected and analyzed by electrothermal atomic absorption spectrometry prior to microwave-assisted acid digestion. The average As concentrations in groundwater samples of two towns, Thari Mirwah and Gambat, were found to be 28.5 and 98.3 μg/L, respectively. The range of As concentrations in scalp hair samples of children who belong to Thari Mirwah and Gambat was 1.25-1.61 μg/g and 1.73-3.63 μg/g, respectively. Twenty percent of the total children who belong to Gambat have skin lesions on their hands and feet. A positive correlation coefficient (R = 0.91-0.99) was obtained between As contents in drinking water and scalp hairs of children of both towns.