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Evidence regarding the role of mercury and aluminum in the pathogenesis of Alzheimer's disease (AD) remains controversial. The aims of our project were to investigate the content of the selected metals in brain tissue samples and the use of a specific mathematical transform to eliminate the disadvantage of a strong positive skew in the original data distribution. In this study, we used atomic absorption spectrophotometry to determine mercury and aluminum concentrations in the hippocampus and associative visual cortex of 29 neuropathologically confirmed AD and 27 age-matched controls. The Box-Cox data transformation was used for statistical evaluation. AD brains had higher mean aluminum concentrations in the hippocampus than controls (0.357 vs. 0.090 μg/g; P = 0.039) after data transformation. Results for mercury were not significant. Original data regarding microelement concentrations are heavily skewed and do not pass the normality test in general. A Box-Cox transformation can eliminate this disadvantage and allow parametric testing.

Male Wistar rats were given 0.5 and 2% lead acetate in drinking water for 2 months, 1% lead acetate for 3 months and sodium acetate equimolar to 2% lead acetate for 3 months. Glucose, total proteins, lactate dehydrogenase (LDH), lysozyme and beta 2-microglobulin (beta 2-m) were measured in 24-h urine every month. Kidney weight and histology were also examined. At the three doses, lead exposure produced a significant elevation of the kidney weight. No significant change in urinary parameters was observed in rats given 0.5% lead acetate. Exposure to 1% lead acetate increased the urinary excretion of beta 2-m only. At the 2% lead acetate dose the elevation of beta 2-m excretion was accompanied by an increased urinary output of glucose, total proteins, lysozyme and LDH. Observations of the kidneys by light microscopy were in agreement with these biochemical findings. The nephrotoxic effect of acetate was excluded by the lack of biochemical or histological effects of sodium acetate on the kidney. It is concluded that a proximal tubular dysfunction is induced in rats chronically exposed to high doses of lead.

Human biomonitoring (HBM) is an effective tool for assessing actual exposure to chemicals that takes into account all routes of intake. Although hair analysis is considered to be an optimal biomarker for assessing mercury exposure, the lack of harmonization as regards sampling and analytical procedures has often limited the comparison of data at national and international level. The European-funded projects COPHES and DEMOCOPHES developed and tested a harmonized European approach to Human Biomonitoring in response to the European Environment and Health Action Plan. Herein we describe the quality assurance program (QAP) for assessing mercury levels in hair samples from more than 1800 mother-child pairs recruited in 17 European countries. To ensure the comparability of the results, standard operating procedures (SOPs) for sampling and for mercury analysis were drafted and distributed to participating laboratories. Training sessions were organized for field workers and four external quality-assessment exercises (ICI/EQUAS), followed by the corresponding web conferences, were organized between March 2011 and February 2012. ICI/EQUAS used native hair samples at two mercury concentration ranges (0.20-0.71 and 0.80-1.63) per exercise. The results revealed relative standard deviations of 7.87-13.55% and 4.04-11.31% for the low and high mercury concentration ranges, respectively. A total of 16 out of 18 participating laboratories the QAP requirements and were allowed to analyze samples from the DEMOCOPHES pilot study. Web conferences after each ICI/EQUAS revealed this to be a new and effective tool for improving analytical performance and increasing capacity building. The procedure developed and tested in COPHES/DEMOCOPHES would be optimal for application on a global scale as regards implementation of the Minamata Convention on Mercury.

The COPHES/DEMOCOPHES twin project was performed in 2011-2012 in 17 European countries to harmonize all steps of the human biomonitoring survey. Urinary cadmium, cotinine, phthalate metabolites, and hair mercury were measured in children (N = 120, 6-11 years) and their mothers of reproductive age, living in urban or rural areas. Cadmium in mothers' and children's urine was detected at a geometric mean (GM) concentration 0.227 and 0.109 μg/L, respectively; 95th percentile (P95) was 0.655 and 0.280 μg/L in mothers and children, respectively. No age-related, education-related, or urban versus rural differences were observed within the frame of each population group. Cadmium urinary level in mothers was about twofold compared with children. Higher levels were obtained in all smoking mothers but not in occasionally smoking or mothers and children exposed to environmental tobacco smoke (ETS). Mercury values in mothers were significantly higher in urban than in rural populations but not in children. GM and P95 for mercury in children's hair were 0.098 and 0.439 μg/g and in mothers' hair were 0.155 and 0.570 μg/g. Concentrations for mercury in the Czech samples were lower than European average. Hair mercury increased significantly with consumption of fish or seafood and with number of amalgam tooth fillings (in children). A positive association was found with family educational level. No influence of age was observed. Urinary cadmium and hair mercury levels were lower than health-based guidelines with one exception. High levels of urinary cotinine were found in the 12 smoking mothers (GM approximately 500 μg/L); lower levels in occasionally smoking mothers, N = 11 (34.5 μg/L). The mean cotinine levels in nonsmoking mothers who reported daily exposure to ETS was 10.7 μg/L. A similar mean value (10.8 μg/L) was obtained in six children who had daily exposure to ETS. In children without exposure to ETS, the mean cotinine level was 1.39 μg/L urine. Cotinine in the urine of children demonstrates limited protection of the Czech children against exposure to ETS.

General population blood concentrations of Pt, Pd and Rh are within or below the single digit ng/L range, much lower than in most previous reports. This is probably due to improved analytical performance, allowing for more reliable information at ultra-trace levels. In general, Mo and Sr agreed with previously reported concentrations. All elements showed geographical and inter-individual variations, but no convincing relationships with self-reported traffic intensity were found. Pt from the antineoplastic drug cis-platinum is retained in the body for years.

Rats were experimentally exposed to the chemical factor, inorganic manganese (Mn), and the physical factor, simulated radiation of mobile phone to detect possible interactions, resulting in changes of brain Mn level or other changes. In acute test, significant increase in brain Mn level was observed in rats exposed to both factors as compared to Mn only. Within subchronic 3-months' test such interaction did not appear, but in vivo observation of exposed rats at the end of the test have demonstrated signficant behavioral changes as compared to unexposed rats.