Biomonitoring of total mercury in urine: method validation and sample stability

Biomonitoring of mercury (Hg) in urine can provide valuable information on environmental exposure to inorganic and elemental Hg. However, this requires a method with a sufficiently low detection limit, and in addition, sample stability during storage needs to be addressed. We adapted a method described in the literature to obtain lower detection limits by decreasing dilution and optimizing the amount of reagents used, while also investigating matrix effects, within- and between measurement variability, and accuracy. We tested Hg stability in urine under different storage conditions and using different stabilizers suggested in the literature. A five-fold dilution of the urine sample with addition of optimized amounts of BrCl gave the best results regarding detection limits, which could be further improved by using a gold amalgamation preconcentration step (Autrap). Application of the method in a biomonitoring study allowed detection of Hg in 95% of the samples without Au trap, and resulted in mercury levels that were comparable to similar populations and influenced by expected variables (age, dental amalgam). Regardless of the sample storage conditions of urine samples in polypropylene bottles, Hg decreased during the first days of storage, then slowly regained or exceeded the originally measured concentration. From these experiments, it appears that storage of the samples frozen at -20°C for several weeks prior to analysis, without the addition of additives is the preferred method.

Assessment of Macrophyte Plant Distribution and PAH Contamination in Selected Aquatic Habitats from an Industrialized City; Kocaeli, Turkey

The macrophyte plant distribution in some aquatic habitats and their availability for monitoring the PAH contamination were investigated in Kocaeli Province of Turkey. Alisma plantago-aquatica L. was collected to evaluate polyaromatic hydrocarbon (PAH) contamination in four aquatic habitats located nearby or distant to the industrial facilities and populated city center. Concentrations of eight PAH congeners were measured in A. plantagoaquatica leaves using gas chromatography. PAH sources were estimated using the following ratios, Fluoranthene / (Fluoranthene + Pyrene), Benzo(a)anthracene / (Benzo(a) anthracene + Chrysene) and Anthracene / (Anthracene + Phenanthrene) and were found to be pyrogenic-sourced in all stations. Since the ratios of congeners indicate the pyrogenic contamination, atmospheric deposition can be considered as the main pathway for PAH transportation. The highest ΣPAH concentration (798 μg kg

Cell-based in vitro models in environmental toxicology: a review

An analysis of biological effects induced by environmental toxins and exposure-related evaluation of potential risks for health and environment represent central tasks in classical biomonitoring. While epidemiological data and population surveys are clearly the methodological frontline of this scientific field, cellbased in vitro assays provide information on toxin-affected cellular pathways and mechanisms, and are important sources for the identification of relevant biomarkers. This review provides an overview on currently available in vitro methods based on cultured cells, as well as some limitations and considerations that are of specific interest in the context of environmental toxicology. Today, a large number of different endpoints can be determined to pinpoint basal and specific toxicological cellular effects. Technological progress and increasingly refined protocols are extending the possibilities of cell-based in vitro assays in environmental toxicology and promoting their increasingly important role in biomonitoring.

Research Article. Perfluoroalkylated substances in human urine: results of a biomonitoring pilot study

Perfluoroalkylated substances (PFASs) are a class of synthetic chemicals used in a wide range of processes and products due to their unique physicalchemical properties. Through intake of PFASs via food or several consumer products, humans can be exposed. Long-chain PFASs have been associated with adverse effects in laboratory animals, and there is also evidence for adverse health effects in humans. Although investigations of human exposure are mainly conducted in blood samples, some studies have shown that especially short-chain PFASs can be detected in human urine. In the present study, a sensitive analytical method was adapted for the measurement of 12 PFASs in human urine samples by HPLC-MS/MS. For verifying this method, concentrations in 11 male and female participants aged 25-46 years were analysed. In the study population, ranges of urinary PFASs concentrations were n.d.- 8.5 ng/l for perfluoropentanoic acid, <LOQ-3.0 ng/l for perfluorohexanoic acid, n.d.-1.8 ng/l for perfluorohexane sulphonate, n.d.-0.99 ng/l for perfluoroheptanoic acid, 0.79-5.1 ng/l for perfluorooctanoic acid, <LOQ-4.9 ng/l for perfluorooctane suphonate, and <LOQ-0.57 ng/l for perfluorononanoic acid. For the other investigated PFASs, no urinary exposure could be identified in any of the samples. The present study shows that several shortchain PFASs are detectable in human urine.

Atmospheric pollution in Kosovo is associated with increased DNA damage in the human population

In order to assess DNA damage associated with exposure to environmental pollution in two polluted sites and one control site in Kosovo, whole blood samples were collected from volunteers in two polluted areas (Kastriot/ Obiliq - lignite-based power plants and lignite mines - and Drenas/Gllogovc - Ferronikeli smelting plant) as well as from Peja, representing an unpolluted area. White blood cells were isolated, and DNA damage was analyzed by the alkaline comet assay. Significantly higher levels of DNA damage (strand breaks) were found in white blood cells from subjects living in the polluted areas compared with residents of the unpolluted city, indicating a potential threat to human health.

Biomonitoring and assessing total mercury concentrations and pools in forested areas

This article focusses on the bio-monitoring of total Hg (THg), sulfur (TS) and carbon (TC) concentrations and pool sizes in forest vegetation and soil layers within the context of a maritime-to-inland transect study in southwestern New Brunswick. This transect stretches from the Grand Manan Island in the Bay of Fundy to the mainland coast (Little Lepreau to New River Beach) and 100 km northward to Fredericton. Along the Bay, frequent summer fogs are thought to have led to increased THg concentrations in forest vegetation and soils such that island THg > coast THg > inland THg concentrations. Transect sampling was done in two phases: (i) a general vegetation and soil survey, and (ii) focusing on specific soil layers (forest floor, top portion of the mineral soils), and select moss and mushrooms species. By way of multiple regression, it was found that soil, moss and mushroom THg and TS were strongly related to one another, with THg decreasing from the island to the inland locations. The accumulated Hg pool within the mineral soil, however, far exceeded (i) the estimated THg pools of the forest biomass (trees, moss and mushrooms) and the forest floor, and (ii) the literature-reported and case-study inferred net input/output rates for annual atmospheric Hg deposition and sequestration, Hg volatilization, and Hg leaching. Partitioning the total soil Hg pool into geogenically and atmospherically derived portions suggested that mineral soils in temperate to boreal forest regions have accumulated and retained atmospherically derived Hg over thousand years and more. These results are summarized in terms of further guiding forest THg monitoring and modelling efforts in terms of specific vegetation and soil sampling targets.

Differences in basal DNA damage in blood cells from men and women

We have recently shown that inhabitants of two polluted areas in Kosovo display more DNA damage (strand breaks in blood cell DNA) than do residents of a cleaner area. Here, we present additional analyses of these data and discuss additional data sets from Kosovo. Based on our data as well as the available data from other authors, age and sex-related differences in DNA damage or in susceptibility to DNA-damaging agents in the environment should be carefully considered when designing biomonitoring studies and when carrying out statistical analysis of the data.

Evaluation of Genotoxic Effects of Asbestos on Occupationally Exposed Workers in Brazil

Genotoxic effects of occupational workers exposed to asbestos can be evaluated using different biomarkers as oxidative stress enzymes in conjuction with comet assay. This study assessed changes to oxidative stress enzymatic parameters and genotoxic damage in workers occupationally exposed and non-exposed to chrysotile asbestos, who attended the outpatient Clinic of the Center for Worker Health Studies and Human Ecology (CESTEH/ENSP/FIOCRUZ) in Brazil. Chest radiography and spirometry were performed to assess clinical progression of symptoms. The traditional visual score comet assay in peripheral whole blood cells was used to assess DNA damage, and oxidative stress was evaluated by measuring catalase (CAT) and glutathione S-transferase (GST) activities. Respiratory alterations were observed in 53% of workers exposed, as determined by pulmonary function and bronchodilation, and 6 workers were diagnosed with asbestosis. The comet assay was statistically significantly higher in the exposed group and individuals with asbestosis compared to the non-exposed group and individuals without asbestosis, respectively. Linear regression analysis showed that 28,4% and 50,5% of comet assay results were increased by exposure to asbestos and developed asbestosis. The results of CAT and GST were not difference between the groups. These results supports the association of genotoxic damage and the onset of asbestosis by chrysotile asbestos exposure in workers of this study.

Human Biomonitoring – An overview on biomarkers and their application in Occupational and Environmental Health

Human biomonitoring (HBM) is a scientificallydeveloped approach for assessing human exposures to natural and synthetic compounds from environment, occupation, and lifestyle. It relies on the measurement of particular substances or biological breakdown products, known as metabolites, in human tissues and/or fluids, and also includes the study of their effects and the possible influence of individual susceptibility as response modulators. HBM is a growing area of knowledge used for exposure and risk assessment in environmental and occupational health, and its importance has been increasing as a result of advancements in the ability to measure greater numbers of chemicals in the human body and tissues. In order to achieve this purpose, HBM focuses on the use of biomarkers as measurable indicators of early changes in biological systems. However, because data interpretation requires caution, it is strongly recommended that the interpretation of HBM results be combined with air monitoring data or pharmacokinetic modelling in order to better understand exposure sources and the metabolism of chemicals.

PAH and PCB Levels in Malva sylvestris L. Specimens Collected from Kocaeli, Turkey

In this study, polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyl (PCB) contaminations in the leaf, stem and root tissues of common mallow (