Hanny Willems

First steps toward harmonized human biomonitoring in Europe: demonstration project to perform human biomonitoring on a European scale.

Background For Europe as a whole, data on internal exposure to environmental chemicals do not yet exist. Characterization of the internal individual chemical environment is expected to enhance understanding of the environmental threats to health. Objectives We developed and applied a harmonized protocol to collect comparable human biomonitoring data all over Europe. Methods In 17 European countries, we measured mercury in hair and cotinine, phthalate metabolites, and cadmium in urine of 1,844 children (5–11 years of age) and their mothers. Specimens were collected over a 5-month period in 2011–2012. We obtained information on personal characteristics, environment, and lifestyle. We used the resulting database to compare concentrations of exposure biomarkers within Europe, to identify determinants of exposure, and to compare exposure biomarkers with health-based guidelines. Results Biomarker concentrations showed a wide variability in the European population. However, levels in children and mothers were highly correlated. Most biomarker concentrations were below the health-based guidance values. Conclusions We have taken the first steps to assess personal chemical exposures in Europe as a whole. Key success factors were the harmonized protocol development, intensive training and capacity building for field work, chemical analysis and communication, as well as stringent quality control programs for chemical and data analysis. Our project demonstrates the feasibility of a Europe-wide human biomonitoring framework to support the decision-making process of environmental measures to protect public health. Citation Den Hond E, Govarts E, Willems H, Smolders R, Casteleyn L, Kolossa-Gehring M, Schwedler G, Seiwert M, Fiddicke U, Castaño A, Esteban M, Angerer J, Koch HM, Schindler BK, Sepai O, Exley K, Bloemen L, Horvat M, Knudsen LE, Joas A, Joas R, Biot P, Aerts D, Koppen G, Katsonouri A, Hadjipanayis A, Krskova A, Maly M, Mørck TA, Rudnai P, Kozepesy S, Mulcahy M, Mannion R, Gutleb AC, Fischer ME, Ligocka D, Jakubowski M, Reis MF, Namorado S, Gurzau AE, Lupsa IR, Halzlova K, Jajcaj M, Mazej D, Snoj Tratnik J, López A, Lopez E, Berglund M, Larsson K, Lehmann A, Crettaz P, Schoeters G. 2015. First steps toward harmonized human biomonitoring in Europe: demonstration project to perform human biomonitoring on a European scale. Environ Health Perspect 123:255–263; http://dx.doi.org/10.1289/ehp.1408616

Phthalates in Belgian cow’s milk and the role of feed and other contamination pathways at farm level

This study investigated the occurrence of dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), benzylbutyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), dicyclohexyl phthalate (DCHP) and di-n-octyl phthalate (DnOP) in raw cows milk and feed from Belgian farms in order to determine their most relevant contamination pathways in milk. Measurable levels of DMP, DEP, DnBP, DCHP and DnOP were found in various feed samples, although they were not observed in milk. A plausible explanation for this is that they are rapidly metabolised in cows. DEHP and in a smaller degree also DiBP and BBP levels in milk seemed to vary across seasons and farms. DiBP and BBP levels were lower in summer than in winter milk, which was in contrast with what was observed for DEHP. This is possibly due to another feed composition during summer and winter. Comparing BBP and DEHP concentrations in manually with those in mechanically obtained milk revealed that, besides environmental contamination via feed ingestion, contact materials used during the mechanical milking process is another important contamination pathway. Concentrations observed in this study confirm the decreasing trend of DEHP in European cows milk owing to the substitution of DEHP by other plasticisers.

Interpreting biomarker data from the COPHES/DEMOCOPHES twin projects: Using external exposure data to understand biomarker differences among countries

In 2011 and 2012, the COPHES/DEMOCOPHES twin projects performed the first ever harmonized human biomonitoring survey in 17 European countries. In more than 1800 mother-child pairs, individual lifestyle data were collected and cadmium, cotinine and certain phthalate metabolites were measured in urine. Total mercury was determined in hair samples. While the main goal of the COPHES/DEMOCOPHES twin projects was to develop and test harmonized protocols and procedures, the goal of the current paper is to investigate whether the observed differences in biomarker values among the countries implementing DEMOCOPHES can be interpreted using information from external databases on environmental quality and lifestyle. In general, 13 countries having implemented DEMOCOPHES provided high-quality data from external sources that were relevant for interpretation purposes. However, some data were not available for reporting or were not in line with predefined specifications. Therefore, only part of the external information could be included in the statistical analyses. Nonetheless, there was a highly significant correlation between national levels of fish consumption and mercury in hair, the strength of antismoking legislation was significantly related to urinary cotinine levels, and we were able to show indications that also urinary cadmium levels were associated with environmental quality and food quality. These results again show the potential of biomonitoring data to provide added value for (the evaluation of) evidence-informed policy making.

A semi-probabilistic modelling approach for the estimation of dietary exposure to phthalates in the Belgian adult population

In this study, a semi-probabilistic modelling approach was applied for the estimation of the long-term human dietary exposure to phthalates--one of worlds most used families of plasticisers. Four phthalate compounds were considered: diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), benzylbutyl phthalate (BBP) and di(2-ethylhexyl) phthalate (DEHP). Intake estimates were calculated for the Belgian adult population and several subgroups of this population for two considered scenarios using an extended version of the EN-forc model. The highest intake rates were found for DEHP, followed by DnBP, BBP and DEP. In the Belgian adult population, men and young adults generally had the highest dietary phthalate intake estimates. Nevertheless, predicted dietary intake rates for all four investigated phthalates were far below the corresponding tolerable daily intake (TDI) values (i.e. P99 intake values were 6.4% of the TDI at most), which is reassuring because adults are also exposed to phthalates via other contamination pathways (e.g. dust ingestion and inhalation). The food groups contributing most to the dietary exposure were grains and grain-based products for DEP, milk and dairy products for DnBP, meat and meat products or grains and grain-based products (depending on the scenario) for BBP and meat and meat products for DEHP. Comparison of the predicted intake results based on modelled phthalate concentrations in food products with intake estimates from other surveys (mostly based on measured concentrations) showed that the extended version of the EN-forc model is a suitable semi-probabilistic tool for the estimation and evaluation of the long-term dietary intake of phthalates in humans.

Lung deposited dose of UFP and PM for cyclists and car passengers in Belgium

Commuter cyclists experience short episodes of high exposure to traffic born air pollution that have potential adverse health effects. We have compared respiratory parameters and exposure to Ultrafine Particles, PM2.5 and PM10 for persons who cycled and drove identical trajectories in three Belgian locations in a pair-wise design. Differences in lung deposited doses are large and consistent across locations. Physical activity significantly increases exposure of cyclists to traffic exhaust. Additional analyses of physiological parameters reveal changes in exhaled NO, serum BDNF and % blood neutrophile cells, but we hypothesize that these effects do not offset the overall health benefits of cycling.

Phthalates in cow milk: possible contamination pathways at farm level

Phthalates are organic lipophilic compounds which are mainly used as plasticizer in plastic polymers. Human exposure occurs mainly via food intake and can cause a wide range of negative health effects. Phthalates are not only present in food because of environmental contamination, but also as a result of migration from contact materials. This study investigated phthalates in cow milk in order to determine the contamination pathways at farm level. The levels of eight phthalates were determined in raw milk samples collected during summer and winter at five farms located in ‘The Kempen’ (Belgium). Both manually obtained milk samples as milk samples milked by machine were collected. Analysis was performed by gas chromatography-mass spectrometry. The analysis of the milk samples milked by machine revealed a difference in average total phthalate level between the summer and the winter sampling period (572 versus 379 µg/kg fat). While the total phthalate levels of the different farms during winter were nearly of similar magnitude (291-587 µg/kg fat), a wide range could be observed during summer (95-1550 µg/kg fat). Comparing milk samples within a farm, lower total phthalate levels were found in the milk samples milked by hand than those by machine (100 versus 179 µg/kg fat). Di(2-ethylhexyl) phthalate which is the most commonly used plasticizer worldwide, was the most dominating one (79 % of the total concentration in milk from the central collecting tank). The results indicate that the contamination pathways for phthalates in cow milk vary across seasons. An explanation therefore is that the feed composition is different during summer than during winter. In summer, cows are grazing in the fields where an extra phthalate contamination can occur via soil ingestion. Comparing the milk samples milked by hand with those by machine reveals that the milking equipment is another important contamination pathway.The International Society for Environmental Epidemiology (ISEE) is an international organization with almost 1000 members from more than 60 countries. The annual international conference brings together many members and non-members and provides an excellent forum for the discussion of problems and benefits related to the environment and human health. Specific themes for the 23rd Annual Conference include: Sustainable transport and health: Impact of transport on health and approaches to reduce health impacts, Impact of climate change: from water scarcity to Saharan dust episodes, Early exposure - later life: in utero and early life exposures and effects in later life, New methods and technologies.Background and Aims: Phthalates are used in many industrial and consumer products. High-molecular-weight phthalates are primarily used as plasticizers to soften PVC products, while low-molecular-weight phthalates are widely used as solvents to hold colour and scent in products. Phthalates have been detected in food and also measured in humans. This study investigated phthalates in food products on the Belgian market in order to explore possible contamination pathways. Methods: 650 Representative samples of widely consumed foods were purchased in Belgian shops. The levels of eight phthalates were determined and product specific properties were stored in a database. This database was used to explore the contamination pathways by identifying relations between sample properties (e.g. fat content, pH and packaging) and measured phthalate concentrations. Results: The results of the measurement campaign show a wide variety of phthalate concentrations in the food samples. Concentrations are higher in high-fat food products like butter, oil and cheese compared to low-fat food products, like vegetables and juices. Higher phthalate concentrations were also detected in some cardboard packed food, probably due to migration from inks and glues. Aluminium inner package seems to be a good barrier for migration. A wide range of phthalate levels in bread was found and further research is necessary. Conclusions: A wide variety in phthalate concentration was found. The fat content of the food product, the composition of the food as well as the composition and properties of the packaging material have been identified as possible contamination causing conditions. In a next phase of this study, we will use these data to quantify the dietary intake of phthalates for the Belgian population.