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BACKGROUND: The aim of this study is to examine the effects of age, sex, and race on the excretion and concentrations of albumin, gamma-glutamyl transpeptidase (gamma-GT), N-acetyl-beta-d-glucosaminidase (NAG), alpha(1)-microglobulin (alpha1M), and creatinine in children. STUDY DESIGN: Secondary analysis of a clinical trial, The New England Children's Amalgam Trial, which examined effects of amalgam dental fillings. SETTING & PARTICIPANTS: 534 children aged 6 to 10 years at baseline were recruited from Boston, MA, and rural Maine. PREDICTORS: Age, sex, and race. OUTCOMES & MEASUREMENTS: Urine samples were collected annually for 5 years and analyzed for creatinine, albumin, gamma-GT, NAG, and alpha1M concentrations. Repeated-measures analysis of covariance was used to model effects of age, sex, and race on these values, as well as calculated excretion rates. RESULTS: All measures of creatinine and gamma-GT increased significantly with age. Albumin and gamma-GT concentration and excretion (milligrams per gram of creatinine or units per gram creatinine) were significantly greater for girls compared with boys. alpha1M concentration and creatinine excretion were greater for boys compared with girls. Creatinine concentration was significantly greater for blacks than for whites and Hispanics. Creatinine excretion and all gamma-GT levels were significantly greater for blacks and Hispanics compared with non-Hispanic whites. LIMITATIONS: The study population, recruited for a clinical trial, was of lower socioeconomic status than the general population. The high limit of detection for alpha1M resulted in a majority of samples less than the detection limit. CONCLUSIONS: We recommend considering age, sex, and race in the interpretation of urinary markers. It also is recommended that epidemiological studies and clinical trials account for age, sex, and race in statistical models comparing urinary markers of kidney damage.Copyright © 2007 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

The permanent teeth of 516 7- and 8-year-old Swedish children from a low-fluoride area were examined for developmental enamel defects. Special attention was paid to demarcated opacities in permanent first molars and permanent incisors (MIH). The examination was done in their schools, using a portable light, a mirror, and a probe. The modified DDE index of 1992 was used for recording the enamel defects, supplemented with a further classification into severe, moderate, and mild defects. Demarcated opacities in permanent first molars were present in 18.4% of the children. The mean number of hypomineralized teeth of the affected children was 3.2 (standard deviation, 1.8), of which 2.4 were first molars. Of the children 6.5% had severe defects, 5% had moderate defects, whereas 7% had only mildly hypomineralized teeth. In conclusion, hypomineralized first molars appeared to be common and require considerable treatment in the Swedish child population. [ABSTRACT FROM AUTHOR]

Dentistry usually is 'wet work' with risk of damage to the skin barrier, and the hands may be exposed to skin irritants and contact-sensitizing substances used in dental materials or gloves. Airway irritants may also be present. This study assessed the consequences of work-related skin and airway symptoms among dentists in terms of contact with health authorities, sick leave, or changes in the professional career. A questionnaire on these factors was answered by more than 3000 Swedish dentists. Only 6% of the respondents had consulted a physician, although 22% had noted work-related skin symptoms. In 2% the skin symptoms had caused sick leave, and about 2% had reported their skin symptoms as an occupational disease. Two per cent had consulted a physician owing to work-related airway symptoms, which is a minor part of the 13% who had experienced such symptoms when in contact with dental materials. Twenty-five dentists (<1%) had been on sick leave because of work-related airway symptoms. Only 1 dentists reported change of activities or occupation owing to work-related skin or airway symptoms, and in most cases these symptoms only contributed to their decision. In summary, whereas sick leave in dentists because of musculoskeletal problems may be common, the present study shows that this is not the case for work-related skin or airway symptoms, and such symptoms seldom affect the dentists' professional career. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the influence of chronic toxic encephalopathy (CTE) on Trail Making Test (TMT) performance, with special focus on the discriminative potential of this test. We assessed TMT performance in patients diagnosed with CTE, patients with similar symptoms but no diagnosis, and healthy participants. Inferior performance was seen in CTE, and increasing age had a negative effect on TMT performance only for the CTE group. This effect was most pronounced in TMT-B. However, the ability of the TMT to identify CTE was low, whereas all healthy participants were identified as healthy. Thus, the sensitivity of TMT alone was low, but it succeeded in correctly classifying normal subjects. The pattern of results indicates that normal TMT performance may be seen in individuals with mild to moderate brain syndromes, such as CTE, whereas poor performance should not be expected in healthy individuals. [ABSTRACT FROM AUTHOR]

Objective: The aim was to study whether functional impairment of the pituitary, thyroid, testes, and adrenal glands of humans occupationally exposed to mercury (Hg) vapour can be shown as a result of accumulation of Hg in these glands.Methods: Basal concentrations of thyrotrophin (TSH), prolactin, free thyroxine (free T4), free 3,5,3'-triiodothyronine (free T3), antibodies against thyroperoxidase, and testosterone in serum, as well as cortisol in morning urine were measured in 41 chloralkali workers exposed (10 years on average) to Hg vapour, and in 41 age matched occupationally unexposed referents. The chloralkali workers had a mean urinary Hg concentration (U-Hg) of 15 nmol/mmol (27 micrograms/g) creatinine, and a mean blood Hg concentration (B-Hg) of 46 nmol/l. For the reference group U-Hg and B-Hg were 1.9 nmol/mmol (3.3 micrograms/g) creatinine and 17 nmol/l respectively.Results: The serum free T4 concentration and the ratio free T4/free T3 were slightly, but significantly, higher in the subgroups with the highest exposure, and the serum free T3 was inversely associated with cumulative Hg exposure. This indicates a possible inhibitory effect of mercury on 5'-deiodinases, which are responsible for the conversion of T4 to the active hormone T3. Serum total testosterone, but not free testosterone, was positively correlated with cumulative Hg exposure. Prolactin, TSH and urinary cortisol concentrations were not significantly associated to exposure.Conclusion: Apart from inhibition of the deiodination of T4 to T3, the endocrine functions studied seem not to be affected by exposure to Hg vapour at the exposure levels of the present study. Growth hormone secretion was not studied. [ABSTRACT FROM AUTHOR]

The elimination of mercury (Hg) in urine was investigated in 12 former chloro-alkali workers exposed to metallic Hg vapour for two to 18 (median five) years. Morning urine samples were taken on several (median 9) occasions after change of employment or retirement. The median follow up time was 28 months. The decrease in concentration of Hg in urine (U-Hg) was well characterised by a one compartment model. Three different regression methods were used; non-linear least squares regression (NLSR), weighted non-linear least squares regression (WNLSR), and linear least squares regression (LLSR) after log transformation of the U-Hg data. The median half life from the WNLSR method was 55 days. There were no large differences in the half life estimates given by the WNLSR or the NLSR methods, but for five subjects the LLSR method gave poor fits. There was a non-significant tendency towards longer half lives with higher initial U-Hg. About three years after the cessation of occupational exposure a mobilisation test with 2,3-dimercaptopropane-1-sulphonate (DMPS) was performed on seven subjects. Excretion of Hg, copper (Cu), and zinc (Zn) in urine was estimated before and after the ingestion of 300 mg of DMPS. Treatment with DMPS increased 24 hour urinary excretion by a factor of 7.6 for Hg, 12 for Cu, and 1.5 for Zn. The relative increase in U-Hg was not significantly higher than that obtained in a previous study of an occupationally unexposed group. A major proportion (62%) of Hg excreted during 24 hours after DMPS appeared in the first six hours. [ABSTRACT FROM AUTHOR]

Exposure of the staffs to static magnetic fields of NMR-units, was investigated at two departments for chemical analysis (static field strength of the systems 11.7 and 4.7 Tesla) and two for clinical imaging (0.5 and 0.02 Tesla). The exposure time was estimated by personal interviews. The magnetic flux density was highly dependent on distance to the magnet, and the magnetic fields in normal work with the NMR-units were, during most working time, lower than 1 milliTesla (mT), which is far below the whole-body limit recommended by the American Conference of Governmental and Industrial Hygienists (60 mT), the British National Radiation Protection Board (200 mT), or the International Commission on Non-Ionizing Radiation Protection (200 mT). During short periods, when changing samples or assisting anxious patients, the fields may be strong (100–150 mT). The recommended ceiling values (2–5 Tesla) are, however, not exceeded. [ABSTRACT FROM PUBLISHER]

Abstract Background Residential wood combustion is now recognized as a major particle source in many developed countries, and the number of studies investigating the negative health effects associated with wood smoke exposure is currently increasing. The combustion appliances in use today provide highly variable combustion conditions resulting in large variations in the physicochemical characteristics of the emitted particles. These differences in physicochemical properties are likely to influence the biological effects induced by the wood smoke particles. Outline The focus of this review is to discuss the present knowledge on physicochemical properties of wood smoke particles from different combustion conditions in relation to wood smoke-induced health effects. In addition, the human wood smoke exposure in developed countries is explored in order to identify the particle characteristics that are relevant for experimental studies of wood smoke-induced health effects. Finally, recent experimental studies regarding wood smoke exposure are discussed with respect to the applied combustion conditions and particle properties. Conclusion Overall, the reviewed literature regarding the physicochemical properties of wood smoke particles provides a relatively clear picture of how these properties vary with the combustion conditions, whereas particle emissions from specific classes of combustion appliances are less well characterised. The major gaps in knowledge concern; (i) characterisation of the atmospheric transformations of wood smoke particles, (ii) characterisation of the physicochemical properties of wood smoke particles in ambient and indoor environments, and (iii) identification of the physicochemical properties that influence the biological effects of wood smoke particles.

Abstract Background Particulate air pollution is associated with increased risk of cardiovascular events although the involved mechanisms are poorly understood. The objective of the present study was to investigate the effects of controlled exposure to ambient air fine and ultrafine particles on microvascular function and biomarkers related to inflammation, haemostasis and lipid and protein oxidation. Methods Twenty-nine subjects participated in a randomized, two-factor crossover study with or without biking exercise for 180 minutes and with 24 hour exposure to particle rich (number concentrations, NC: 11600 ± 5600 per cm3, mass concentrations: 13.8 ± 7.4 μg/m3 and 10.5 ± 4.8 μg/m3 for PM10-2.5 and PM2.5, respectively) or particle filtered (NC: 555 ± 1053 per cm3) air collected above a busy street. Microvascular function was assessed non-invasively by measuring digital peripheral artery tone following arm ischemia. Biomarkers included haemoglobin, red blood cells, platelet count, coagulation factors, C-reactive protein, fibrinogen, interleukin-6, tumour necrosis factor α, lag time to copper-induced oxidation of plasma lipids and protein oxidation measured as 2-aminoadipic semialdehyde in plasma. Results No statistically significant differences were observed on microvascular function or the biomarkers after exposure to particle rich or particle filtered air. Conclusion This study indicates that exposure to air pollution particles at outdoor concentrations is not associated with detectable systemic inflammation, lipid or protein oxidation, altered haemostasis or microvascular function in young healthy participants.

The European Commission asked EFSA for a risk assessment on small organoarsenic species in food. For monomethylarsonic acid MMA(V), decreased body weight resulting from diarrhoea in rats was identified as the critical endpoint and a BMDL 10 of 18.2 mg MMA(V)/kg body weight (bw) per day (equivalent to 9.7 mg As/kg bw per day) was calculated as a reference point (RP). For dimethylarsinic acid DMA(V), increased incidence in urinary bladder tumours in rats was identified as the critical endpoint. A BMDL 10 of 1.1 mg DMA(V)/kg bw per day (equivalent to 0.6 mg As/kg bw per day) was calculated as an RP. For other small organoarsenic species, the toxicological data are insufficient to identify critical effects and RPs, and they could not be included in the risk assessment. For both MMA(V) and DMA(V), the toxicological database is incomplete and a margin of exposure (MOE) approach was applied for risk characterisation. The highest chronic dietary exposure to DMA(V) was estimated in 'Toddlers', with rice and fish meat as the main contributors across population groups. For MMA(V), the highest chronic dietary exposures were estimated for high consumers of fish meat and processed/preserved fish in 'Infants' and 'Elderly' age class, respectively. For MMA(V), an MOE of ≥ 500 was identified not to raise a health concern. For MMA(V), all MOEs were well above 500 for average and high consumers and thus do not raise a health concern. For DMA(V), an MOE of 10,000 was identified as of low health concern as it is genotoxic and carcinogenic, although the mechanisms of genotoxicity and its role in carcinogenicity of DMA(V) are not fully elucidated. For DMA(V), MOEs were below 10,000 in many cases across dietary surveys and age groups, in particular for some 95th percentile exposures. The Panel considers that this would raise a health concern., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)