Trace element levels: How Substance Use Disorder (SUD) contributes to the alteration of urinary essential and toxic element levels.

Increasing illicit drug use is one of the main problems in most countries or societies. Monitoring heavy metals and trace elements in this vulnerable group seems to be necessary. Therefore, we assessed the urinary trace element and toxic metals/metalloids concentrations (Zinc (Zn), Iron (Fe), Copper (Cu), Chromium (Cr), Lead (Pb), Cadmium (Cd), Arsenic (As), Nickel (Ni), and Mercury (Hg)) in opium, tramadol, and cannabis users compared to healthy subjects. In this cross-sectional study, patients with substance use disorder (SUD) (n = 74) were divided into four groups: cannabis, tramadol, opium, and mixed (simultaneous use of more than one of the three studied substances), along with a healthy group (n = 60). Urine samples were prepared by dispersive liquid-liquid microextraction method so that heavy metals/metalloids could be measured by ICP-MS. The mean urinary concentration of Cu (48.15 vs. 25.45; 89.2%, p<0.001), Hg (1.3 vs. 0.10; 1200%, p < 0.001), and Zn (301.95 vs. 210; 43.8%, p < 0.001) was markedly lower among patients with SUD. The mean urinary concentration of other elements including As (1.9 vs. 4.1; 115.8%), Cd (0.1 vs. 1.10; 1000%), Cr (6.80 vs. 11.65; 71.3%), Ni (2.95 vs. 4.95; 67.8%), and Pb (1.5 vs. 7.9; 426.6%) were significantly higher among patients with SUD compared to healthy subjects. When sub-groups were compared, no significant differences were observed between their trace element levels (Kruskal-Wallis test, p > 0.05). This can be an indication that regardless of the type of drug, the levels of trace elements are changed with respect to healthy individuals. Our results showed that illicit drug use causes changes in urinary trace element/heavy metal/metalloid levels and highlights the need for monitoring heavy metals and trace elements in individuals with substance use disorder. Assessment of different elements in biological samples of drug dependents may be useful for implementing new prevention and treatment protocols. In case of changes in their levels, complementary recommendations, attention to diet, and periodic assessment of toxic metal levels within treatment programs will be needed.

Method validation for (ultra)-trace element concentrations in urine for small sample volumes in large epidemiological studies: application to the population-based epidemiological multi-ethnic study of atherosclerosis (MESA).

Analysis of essential and non-essential trace elements in urine has emerged as a valuable tool for assessing occupational and environmental exposures, diagnosing nutritional status and guiding public health and health care intervention. Our study focused on the analysis of trace elements in urine samples from the Multi-Ethnic Study of Atherosclerosis (MESA), a precious resource for health research with limited sample volumes. Here we provide a comprehensive and sensitive method for the analysis of 18 elements using only 100 µL of urine. Method sensitivity, accuracy, and precision were assessed. The analysis by inductively coupled plasma mass spectrometry (ICP-MS) included the measurement of antimony (Sb), arsenic (As), barium (Ba), cadmium (Cd), cesium (Cs), cobalt (Co), copper (Cu), gadolinium (Gd), lead (Pb), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se), strontium (Sr), thallium (Tl), tungsten (W), uranium (U), and zinc (Zn). Further, we reported urinary trace element concentrations by covariates including gender, ethnicity/race, smoking and location. The results showed good accuracy and sensitivity of the ICP-MS method with the limit of detections rangings between 0.001 µg L-1 for U to 6.2 µg L-1 for Zn. Intra-day precision for MESA urine analysis varied between 1.4% for Mo and 26% for Mn (average 6.4% for all elements). The average inter-day precision for most elements was <8.5% except for Gd (20%), U (16%) and Mn (19%) due to very low urinary concentrations. Urinary mean concentrations of non-essential elements followed the order of Sr > As > Cs > Ni > Ba > Pb > Cd > Gd > Tl > W > U. The order of urinary mean concentrations for essential trace elements was Zn > Se > Mo > Cu > Co > Mn. Non-adjusted mean concentration of non-essential trace elements in urine from MESA participants follow the order Sr > As > Cs > Ni > Ba > Pb > Cd > Gd > Tl > W > U. The unadjusted urinary mean concentrations of essential trace elements decrease from Zn > Se > Mo > Cu > Co > Mn.

Exposure of environmental trace elements in prostate cancer patients: A multiple metal analysis.

Prostate cancer (PCa) is the second leading cause of cancer-related deaths among men. To elucidate the connection between trace elements (arsenic: As, cadmium: Cd, lead: Pb, chromium: Cr, and nickel: Ni) and the risk of PCa, we analyzed trace element levels in the serum, urine, and tissues of PCa patients, while also examining their smoking status. We correlated these levels with their smoking habits. Notably, levels of Cd (P ≤ 0.05) and As (P ≤ 0.01) were significantly higher in the tumor tissue than in adjacent tissues. No significant differences were observed in the levels of Pb, Cr and Ni. Additionally, urinary Cd levels in 70% and arsenic levels in 2.3% of the PCa cohort were markedly higher than the CDC-reported cutoff (Cd ≤ 0.185 µg/L & As ≤100 µg/L). None displayed elevated levels of urinary Pb, Cr, and Ni. Conversely, in serum samples, the concentration of arsenic exceeded the CDC-determined limit (As ≤1.0 µg/L) in 31.69% of PCa patients. However, only 7.04% of patients had higher serum Cd levels than the CDC standard values (Cd ≤ 0.315 µg/L), while all PCa patients exceeded the Cr CDC limit (Cr ≤ 0.16 µg/L) and the Ni CDC limit (Ni ≤ 0.2 µg/L). On the contrary, no significant differences were observed in serum Pb (Pb ≤ 35.0 µg/L). Our findings establish a positive link between Cd and arsenic tissue concentrations and the risk of PCa. Subsequent studies are essential to determine whether elevated trace element levels pose a risk for the development of prostate carcinogenesis. Interestingly, among the PCa cohort comprising smokers, notably higher Cd levels were observed only in tumor tissues (P ≤ 0.01) and urine (P ≤ 0.05) compared to other elements or in other specimens.

Low-Iodine Diet of 4 Days Is Sufficient Preparation for 131I Therapy in Differentiated Thyroid Cancer Patients.

CONTEXT: No consensus exists about the optimal duration of the low-iodine diet (LID) in the preparation of 131I therapy in differentiated thyroid cancer (DTC) patients. OBJECTIVE: This work aimed to investigate if a LID of 4 days is enough to achieve adequate iodine depletion in preparation for 131I therapy. In addition, the nutritional status of the LID was evaluated. METHODS: In this prospective study, 65 DTC patients treated at 2 university medical centers were included between 2018 and 2021. The patients collected 24-hour urine on days 4 and 7 of the LID and kept a food diary before and during the LID. The primary outcome was the difference between the 24-hour urinary iodine excretion (UIE) on both days. RESULTS: The median 24-hour UIE on days 4 and 7 of the LID were not significantly different (36.1 mcg [interquartile range, 25.4-51.2 mcg] and 36.5 mcg [interquartile range, 23.9-47.7 mcg], respectively, P = .43). On day 4 of the LID, 72.1% of the DTC patients were adequately prepared (24-hour UIE < 50 mcg), and 82.0% of the DTC patients on day 7 (P = .18). Compared to the self-reported regular diet, DTC patients showed a significantly (P < .01) lower percentage of nutrient intake (calories, protein, calcium, iodine, and water) during the LID. CONCLUSION: The 24-hour UIE on day 4 of the LID did not differ from day 7, and therefore shortening the LID from 7 to 4 days seems justified to prepare DTC patients for 131I therapy in areas with sufficient iodine intake and may be beneficial to maintain a sufficient nutritional intake during DTC treatment.

Health effects of selected trace elements in hairdressing cosmetics on hairdressers in Enugu, Nigeria.

Could trace elements in hairdressing cosmetics prove carcinogenic to hairdressers, who use them regularly as raw materials in hairdressing business? The toxic effects of selected trace elements contained in hairdressing cosmetics on hairdressers were investigated by regressing the quality of life values for hairdressers with their blood/urine levels of the toxic metals A hundred subjects were randomly drawn from a cluster of hairdressers. Blood lead level, 17.47 ± 4.59 µg/dL, confirmed that the hairdressers were regularly exposed to lead. Mean blood mercury level, 25.06 ± 4.11 ng/dL, was above the normal blood mercury concentration of less than 10-20 ng/mL. Mean blood cadmium level, 3.64 ± 1.87 µg/dL, was within the normal range, < 5.0 µg/dL. Mean urine arsenic level, 96.16 ± 38.34 µg/L, was above normal range, ≤ 50 µg/dL, but within high normal range, > 50 to < 200 µg/dL. Blood nickel level, 0.49 ± 0.20 µg/dL, was above both the healthy range, 0.14-0.65 µg/dL, and the most reliable value of 0.2 µg/dL. Negative correlations existed between the quality of life and levels for lead (R = - .017), mercury (R = - .008), arsenic (R = - .072) and nickel (R = - .168), but there was positive correlation with cadmium level (R = .123). At 0.096, the probability value (p value) for nickel was significant at 10%. P value as insignificant at 1%, 5% and 10% for lead (0.868), mercury (0.940), cadmium (0.224) and arsenic (0.475). Therefore, Ni contained in hairdressing cosmetics might have carcinogenic effects that affected the quality of life of hairdressers, unlike other trace elements tested, namely, lead, mercury, cadmium and arsenic. Further research with the tumor markers assessment is recommended to confirm the carcinogenic effect of Ni.

Trace Element and Mineral Levels in Serum, Hair, and Urine of Obese Women in Relation to Body Composition, Blood Pressure, Lipid Profile, and Insulin Resistance.

The objective of this study was to evaluate serum, hair, and urinary trace element and mineral content in normal-weight and obese women in relation to metabolic risk factors. A total of 80 women aged 30-70 y.o. were enrolled in the obese group (n = 40) and normal-weight group (n = 40). Serum, hair, and urinary trace element and mineral levels were assessed using inductively coupled plasma spectrometry. Body fat percentage was evaluated using bioimpedance. Obese subjects were characterized by significantly higher body fat percentage, blood pressure, serum triglyceride concentration, and insulin resistance. Serum Ca, Fe, Mg, Se, V, Zn levels, hair Fe, Mg, V content, and urinary Se and V concentrations were found to be lower in obese subjects as compared to lean controls. In turn, serum Cu and urinary Fe levels in obese women were characterized by a significant increase. In multiple regression models serum Cu, Se, and Zn levels were significantly associated with BMI even after adjustment for blood biochemistry, body composition, and blood pressure. Serum trace element and mineral levels also significantly contributed to group discrimination. These findings allow to propose that obesity-associated disturbances in trace element and mineral status may at least partially contribute to metabolic risk in obese subjects.

Associations between essential microelements exposure and the aggressive clinicopathologic characteristics of papillary thyroid cancer.

Aim of this study was to evaluate the association between multiple essential microelements exposure and the aggressive clinicopathologic characteristics of papillary thyroid carcinoma (PTC). The concentrations of 10 essential microelements in urine [cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se), strontium (Sr), zinc (Zn), and iodine (I)] were measured in 608 patients newly diagnosed with PTC, including 154 males and 454 females. Chi square test and Wilcoxon rank sum test were used to compare general characteristics among males and females. Multivariate logistic regression was used to evaluate the associations between essential microelements and PTC clinicopathologic characteristics in single- and multi-microelement models. In this study, we only observed that the frequency of lymph node metastasis in males was higher than in females, and males had higher levels of zinc than females, but males had lower levels of iodine than females. It was found that high levels of Fe were associated with decreased risk of PTC tumor size > 1 cm, capsular invasion, and advanced T stage (T3/4a/4b). High levels of Co and Mo were associated with decreased risk of capsular invasion and lymph node metastasis, respectively. However, high levels of Mn and Sr were associated with increased risk of capsular invasion and multifocality respectively, and both were associated with increased risk of advanced T stage (T3/4a/4b). These findings indicated that certain essential microelements might have potential effects on PTC progression and aggressiveness. Further studies are required to confirm these findings.

Biomonitorization of concentrations of 28 elements in serum and urine among workers exposed to indium compounds.

Many studies have documented the abnormal concentrations of metals/metalloids in serum or urine of occupational workers, but no works systematically analysed the concentrations of elements in serum or urine of indium-exposed workers. This study was aimed to assess 28 elements in serum and urine from 57 individuals with occupational exposure to indium and its compounds. Control subjects were 63 workers without metal exposure. We collected information on occupation and lifestyle habits by questionnaire. Biological samples were collected to quantify elements by inductive coupled plasma-mass spectrometer. Air in the breathing zones was drawn at flow rates of 1.5-3 L/min for a sampling period of 6 to 8 h, using a Model BFC-35 pump. The average ambient indium level was 0.078 mg/m3. Serum/urine Indium levels were significantly higher in indium-exposed workers than in controls (P < 0.01). Moreover, serum/urine indium concentrations in the group with 6-14 years and ≥15 years of employment were significantly higher than those with ≤5 employment years(P < 0.05). Ten of the other 27 elements/metals measured were higher in serum/urine in indium-exposed workers compared to the controls (aluminum, beryllium, cadmium, cesium, chromium, lithium, manganese, magnesium, molybdenum and vanadium). Zinc levels in serum/urine were significantly decreased in the indium-exposed workers. Additionally, other elements/metals were higher in one specimen (serum or urine) but lower in the other (Selenium was lower in serum but higher in urine in the indium-exposed workers compared with the controls; likewise Thallium and Rubidium were higher in serum but lower in urine). Linear regression analyses, revealed significant correlations between serum and urine for indium, aluminum, arsenic, barium, cadmium, cesium, cobalt, selenium, silver, and zinc (P < 0.05). These data suggest that occupational exposure to indium and its compounds may disturb the homeostasis of trace elements in systemic circulation, indium concentrations in serum or urine appear reflective of workers' exposure to ambient indium and their years of working, respectively. The serum/urine levels of essential metals are modified by exposure to indium in occupationally exposed workers. Further studies including larger sample size and more kinds of biological sample are needed to validate our findings.

A case-control study on the association of mineral elements exposure and thyroid tumor and goiter.

Thyroid tumor and thyroid goiter are prevalent disease around the world. In this case-control study, we investigated the association between exposure to a total of twelve mineral elements and thyroid disease as well as thyroid functions. Participants with thyroid tumor or goiter (N = 197) were matched with a healthy population (N = 197) by age (± 2 years old) and same sex. Questionnaires were used to collect data about the demographic characteristics and information of subjects. Serum and urine samples were collected simultaneously for each of the subjects. Mineral elements, iodine level of urine and levels of the total seven thyroid function indexes in serum were detected respectively. Conditional logistic regression was applied to estimate the associations between mineral elements and the risk of thyroid tumor and goiter through single-element models and multiple-element models. Multiple linear regression was used to evaluate relationships between mineral elements and percentage changes of thyroid functions. Higher concentrations of mineral elements in the recruited population were found in this study than other comparable studies, and the levels of chromium (Cr), manganese (Mn), nickel (Ni), arsenic (As), cadmium (Cd), selenium (Se), antimony (Sb), thallium (Tl) and lead (Pb) in the case group were lower than the control group. According to the single-element models, Cr, Mn, Ni, Sb and Tl showed significant negative associations with the risk of thyroid tumor and goiter, and, Cd showed nonmonotonic dose response. Cd and mercury (Hg) showed a nonmonotonic percentage change with T4, while Tl was associated with the increased FT4 in the control group. Therefore, Cd, Hg and Tl may disturb the balance of thyroid function to some extent, and Cr, Mn, Ni, Cd, Sb, and Tl may become potential influencing factors for the risk of thyroid tumor and goiter.

Long-term iodine nutrition is associated with longevity in older adults: a 20 years' follow-up of the Randers-Skagen study.

Iodine intake affects the occurrence of thyroid disorders. However, the association of iodine intake with longevity remains to be described. This led us to perform a 20 years' follow-up on participants from the Randers-Skagen (RaSk) study. Residents in Randers born in 1920 (n 210) and Skagen born in 1918-1923 (n 218) were included in a clinical study in 1997-1998. Mean iodine content in drinking water was 2 µg/l in Randers and 139 µg/l in Skagen. We collected baseline data through questionnaires, performed physical examinations and measured iodine concentrations in spot urine samples. Income data were retrieved from Danish registries. We performed follow-up on mortality until 31 December 2017 using Danish registries. Complete follow-up data were available on 428 out of 430 of participants (99·5 %). At baseline, the median urinary iodine concentration was 55 µg/l in Randers and 160 µg/l in Skagen residents. Participants were long-term residents with 72·8 and 92·7 % residing for more than 25 years in Randers and Skagen, respectively. Cox regression showed that living in Skagen compared with Randers was associated with a lower hazard ratio (HR) of death in both age- and sex-adjusted analyses (HR 0·60, 95 % CI 0·41, 0·87, P = 0·006), but also after adjustment for age, sex, number of drugs, Charlson co-morbidity index, smoking, alcohol and income (HR 0·60, 95 % CI 0·41, 0·87, P = 0·008). Residing in iodine-replete Skagen was associated with increased longevity. This indicates that long-term residency in an iodine-replete environment may be associated with increased longevity compared with residency in an iodine-deficient environment.

Serum and urinary concentrations of arsenic, beryllium, cadmium and lead after an aerobic training period of six months in aerobic athletes and sedentary people.

AIM: The aim of the present study was to evaluate the possible effect of a period of 6 months of aerobic physical training on serum and urinary concentrations of arsenic (As), beryllium (Be), cadmium (Cd) and lead (Pb), potentially toxic minerals. METHODS: Twenty-four well-trained, long distance runners (AG), were recruited at the start of their training period. They had been performing training regularly for the previous 2 years, recording an average volume of 120 km per week of rigorous aerobic exercise aimed at high-level competitions (1500 and 5000 m race modalities). Twenty-six untrained, sedentary participants constituted the control group (CG). All participants had been living in the same geographic area for at least 2 years before the start of the survey. Serum and urine samples were obtained from each participant at the beginning and at the end of the 6 months of the training program. The values of each mineral were determined by inductively coupled plasma mass spectrometry (ICP-MS). Additionally, the daily intake of each mineral was evaluated at both moments in time. RESULTS: The daily concentrations of trace elements in the diet were similar at the start and the end of the training period without differences between groups. In serum, significant differences between groups were observed in As, Cd and Pb (p < 0.05). Attending to time effects, a significant difference was obtained in Pb (p < 0.05). In urine, significant differences between groups were obtained in all minerals (p < 0.05). According to training period, significant differences were observed in As, Be and Pb (p < 0.05). Finally, the group x time interaction revealed significant differences in As and Be (p < 0.05). CONCLUSIONS: Aerobic training may constitute a possibly effective method for increasing the elimination of Cd and Pb potentially toxic minerals from the body, especially among highly trained individuals.

Cigarette Smoking during Pregnancy: Effects on Antioxidant Enzymes, Metallothionein and Trace Elements in Mother-Newborn Pairs.

The effect of maternal smoking as a source of exposure to toxic metals Cd and Pb on superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity, metallothionein (MT), Cd, Pb, Cu, Fe, Mn, Se and Zn concentrations were assessed in maternal and umbilical cord blood and placenta in 74 healthy mother-newborn pairs after term delivery. Sparse discriminant analysis (SDA) was used to identify elements with the strongest impact on the SOD, GPx and MT in the measured compartments, which was then quantified by multiple regression analysis. SOD activity was lower in maternal and cord plasma, and higher in the placenta of smokers compared to non-smokers, whereas GPx activity and MT concentration did not differ between the groups. Although active smoking during pregnancy contributed to higher maternal Cd and Pb concentrations, its contribution to the variability of SOD, GPx or MT after control for other elements identified by SDA was not significant. However, an impaired balance in the antioxidant defence observed in the conditions of relatively low-to-moderate exposure levels to Cd and Pb could contribute to an increased susceptibility of offspring to oxidative stress and risk of disease development later in life. Further study on a larger number of subjects will help to better understand complex interactions between exposure to toxic elements and oxidative stress related to maternal cigarette smoking.

[Bovine trace mineral concentrations in different sample media with emphasis on fecal analysis]. / Konzentration von Spurenelementen beim Rind in verschiedenen Probenmedien unter besonderer Berücksichtigung von Kotproben.

OBJECTIVE: The objective of this study was to evaluate the suitability of feces as sample material for the evaluation of trace mineral supply in cattle. Fecal trace element concentrations of iron, copper, zinc, selenium, manganese and molybdenum were compared with those in feed. Furthermore, fecal trace element-concentrations were compared with those in various additional sample media (serum, plasma, whole blood, urine and hair). MATERIALS AND METHODS: Samples (feces, blood, urine, hair) from up to 10 cows in the close-up (3-0 weeks a. p.) and high-yielding (6-20 weeks p. p.) group each were collected during 73 farm visits on 63 dairy farms. Pooled samples of each lactation group were formed and the concentrations of trace elements were determined with ICP-OES or ICP-MS. Furthermore, TMR was analyzed. Additionally, feces from cattle in cow-calf herds during grazing and housing period were evaluated. RESULTS: Nutritional trace mineral requirements were exceeded by the majority of feeds. Trace mineral concentrations were 2- to 3-fold higher in feces than in feed. In this study, the strongest significant correlation existed between feed and fecal concentrations for all elements. Seasonal variations were detected for iron, copper and manganese. Furthermore, iron concentration differed depending on lactation stage. CONCLUSION AND CLINICAL RELEVANCE: Feed intake of the trace minerals analyzed is most optimally reflected by the fecal concentration in comparison to other substrates. Fecal analysis of these minerals may therefore be employed as an alternative to feed analysis with regards to the evaluation of nutritional trace mineral supply. Analyzing fecal trace mineral concentrations possesses practical significance wherever feed or TMR cannot be analyzed. In particular, this concerns grazing animals, heifers, mother cows and cattle in barns without TMR. Assessment of the complete metabolic status only on the basis of fecal contents is insufficient. However, subnormal fecal copper-, zinc- and manganese concentrations may be suggestive of an inadequate metabolic situation and represent an indication for further diagnostics.

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.

Predictors of urinary and blood Metal(loid) concentrations among pregnant women in Northern Puerto Rico.

Given the potential adverse health effects related to toxic trace metal exposure and insufficient or excessive levels of essential trace metals in pregnant women and their fetuses, the present study characterizes biomarkers of metal and metalloid exposure at repeated time points during pregnancy among women in Puerto Rico. We recruited 1040 pregnant women from prenatal clinics and collected urine, blood, and questionnaire data on demographics, product use, food consumption, and water usage at up to three visits. All samples were analyzed for 16 metal(loid)s: arsenic (As), barium (Ba), beryllium (Be), cadmium (Cd), cobalt (Co), chromium (Cr), cesium (Cs), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), titanium (Ti), uranium (U), vanadium (V), and zinc (Zn). Urine samples were additionally analyzed for molybdenum (Mo), platinum (Pt), antimony (Sb), tin (Sn), and tungsten (W). Mean concentrations of most metal(loid)s were higher among participants compared to the general US female population. We found weak to moderate correlations for inter-matrix comparisons, and moderate to strong correlations between several metal(loid)s measured within each biological matrix. Blood concentrations of Cu, Zn, Mn, Hg, and Pb were shown to reflect reliable biomarkers of exposure. For other metals, repeated samples are recommended for exposure assessment in epidemiology studies. Predictors of metal(loid) biomarkers included fish and rice consumption (urinary As), fish and canned food (blood Hg), drinking public water (blood Pb), smoking (blood Cd), and iron/folic acid supplement use (urinary Cs, Mo, and Sb). Characterization of metal(loid) biomarker variation over time and between matrices, and identification of important exposure sources, may inform future epidemiology studies and exposure reduction strategies.

Sex-Specific Differences in Cognitive Abilities Associated with Childhood Cadmium and Manganese Exposures in School-Age Children: a Prospective Cohort Study.

To examine sex-specific associations of neonatal and childhood exposure to eight trace elements with cognitive abilities of school-age children. The association between exposure and effects was assessed among 296 school-age children from a population-based birth cohort study, who had manganese (Mn), cadmium (Cd), and lead (Pb) exposure measured in cord blood and chromium (Cr), manganese, cobalt (Co), copper (Cu), arsenic (As), selenium (Se), cadmium, and lead exposure quantified in spot urine. Cognitive abilities were assessed using the Wechsler Intelligence Scale for Children-Chinese Revised (WISC-CR). Generalized linear models were performed to analyze associations of intelligence quotient (IQ) with trace element concentrations in cord blood and urinary trace element levels. General linear models were used to evaluate association between exposure fluctuation and children's IQ. Urinary Cd concentrations were negatively associated with full-scale IQ (ß = - 3.469, 95% confidence interval (CI) - 6.291, - 0.647; p = 0.016) and performance IQ (ß = - 4.012, 95% CI - 7.088, - 0.936; p = 0.011) in girls; however, neonatal Cd exposure expressed as Cd concentrations in cord blood was in inverse associations with verbal IQ (ß = - 2.590, 95% CI - 4.570, - 0.609; p = 0.010) only in boys. Positive association between urinary Mn concentrations and performance IQ (ß = 1.305, 95% CI 0.035, 2.575; p = 0.044) of children was observed, especially in girls. In addition, inverse association of urinary Cu concentrations with verbal IQ (ß = - 2.200, 95% CI - 4.360, - 0.039; p = 0.046) was only found in boys. Childhood Cd exposure may adversely affect cognitive abilities, while Mn exposure may beneficially modify cognitive abilities of school-age children, particularly in girls.

Influence of a 6-month physical training program on serum and urinary concentrations of trace metals in middle distance elite runners.

BACKGROUND: The aim of this survey was to determine the effects of an aerobic physical training program of six months duration on the serum and urinary concentrations of essential trace elements among middle distance runners and untrained, non-sportsmen participants. METHODS: 24 well-trained, middle-distance (1500 and 5000 m), aerobic male runners (AG) were recruited at the beginning of their training season and 26 untrained males formed the control group (CG). All participants were from the same region of Spain, and all of them had been living in this area for at least two years. Serum and urine of samples of Cobalt (Co), Copper (Cu), Manganese (Mn), Molybdenum (Mo), Selenium (Se), Vanadium (V) and Zinc (Zn) were obtained at the beginning of the training season, and six months later, from all participants. All samples were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: Two-way ANOVA showed significant differences relative to group effect in serum concentrations of Co, Cu, Mn, Mo, Se and Zn. Attending to time effect, there were differences in Mn (p = 0.003) and Zn (p = 0.001). The group x time interaction revealed differences only in the case of Mn (p = 0.04). In urine, significant differences between group were obtained in Co, Cu, Mn, Se and V. Time effect showed changes in Co, Cy, Mo and Se. Finally, the group and time interaction revealed significant differences in urinary Cu (p = 0.001), Mn (p = 0.01) and Se (p = 0.001). CONCLUSIONS: A six-month aerobic training program for well-trained athletes induced modifications in the body values of several minerals, a fact which may reflect adaptive responses to physical exercise. The obtained data could be interesting for physicians or coaches in order to consider specific modifications in sportsmen's diets as well as to determine specific nutritional supplementation strategies.

Does relatively low iodine intake contribute to thyroid cancer? An ecological comparison of epidemiology.

Research on the relationship between iodine intake and thyroid cancer (TC) risk is limited, and the findings are inconclusive. The objective of this study was to provide emerging evidence for the association between iodine intake and TC risk in a Chinese population.An ecological study of epidemiology is used to compare the iodine intake among populations with different TC incidence in Zhoushan, China. Incidence rates of TC were investigated and compared among four counties of the Zhoushan Islands from 2014 to 2018. Iodized salt consumption rate and the level of urinary iodine concentration (UIC) were analyzed for pupils and pregnant women from four counties.During 2014 to 2018, a total of 2495 new cases of TC were diagnosed in Zhoushan Islands. The mean crude incidence rate of TC was 51.29 per 100,000 inhabitants, and the standardized (world population) incidence rate (SIR) was 31.34 per 100,000 population. Incidence rates (SIR and crude incidence rates) were significantly higher in women than in men (χ test, P < .05). Both male and female, the incidence of TC in Daishan County is higher than the other three counties of Zhoushan. Iodized salt consumption rate and median UIC in pupils and pregnant women in Daishan County was significantly lower than the other three counties (χ test and Kruskal-Wallis test, all P < .05). The population with high TC incidence has a lower iodized salt consumption and a lower level of UIC compare with the relative low TC incidence populations.The low consumption of iodized salt with mild iodine deficiency may contribute to explain the exceptionally high incidence of TC in Daishan County. Further subtle designed studies are needed to provide additional insights into the epidemiology and etiology of TC and help identify the safe limit of iodine intake for prevention.

[Rapid determination of 21 elements in urine by inductively coupled plasma mass spectrometry].

Objective: To develop a rapid detection method for 21 elements in urine with inductively coupled plasma mass spectrometry (ICP-MS) . Methods: The urine samples were directly diluted 20 times by 1% HNO(3), and detected by ICP-MS, Indium, Yttrium, and Lutecium were used as on-line internal standard. Fe was analyzed by Dynamic Reaction Cell (DRC) mode, As, Cr, V and Zn were analyzed by collision cell technology (CCT) mode, and Be, Mn, Ni, Cd, Sn, Bi, Pb, Re, Sb, W, Li, Cu, Se, Sr, Mo were analyzed by standard mode. Dynamic band-pass tuning (DBT) was used to eliminate interference for Fe. Results: All the elements have good linearity in their determination range, with the correlation coefficient r>0.999 5. The limits of detection of the 21 elements were in the range of 0.017-11.14 µg/L. The inter-precision (relative standard deviation, RSD) was less than 9.96%, and the intra-precision was less than 13.90% (except As RSD<18.91%) . The spike recovery of all elements fell within 81.1%-116.4%. Conclusion: The method was proved to be simple, fast, and accurate, and met the needs of testing requirements of large amounts of specimens.