Bert Morrens

Concept of the Flemish human biomonitoring programme

Since 2002 a human biomonitoring network has been established in Flanders (Belgium) as part of a programme on environmental health surveillance. The human biomonitoring network should support environmental health policy by identifying priorities for further action. The first cycle of the programme (2002-2006) confirmed the hypotheses that living in areas with different environmental pressure is reflected in different loads of environmental chemicals in the residents. In the second cycle of the programme (2007-2011) the number of environmental chemicals for which human biomonitoring data were obtained was expanded substantially. The goal of the Flemish programme is to use and translate the scientific results into policy actions. Its further orientation in the second cycle to human biomonitoring in hot spots and sensitive age groups or susceptible persons with underlying complications (e.g. persons with diabetes) are linked to these goals. Interaction with stakeholders is embedded in the programme emphasizing transparency of the choices that are made and direct communication. The Flemish human biomonitoring programme is organized centrally with major involvement of research partners from different disciplines which allows engrafting environmental health research on the programme. One of the major focuses is the question whether combinations of pollutants in the general population are associated with biological effects. The objective of this paper is to review and discuss the options that were taken in the human biomonitoring programme in order to achieve its goals.

Biomarkers of human exposure to personal care products: Results from the Flemish Environment and Health Study (FLEHS 2007–2011)

Personal care products (PCPs), such as soaps, perfumes, cosmetics, lotions, etc., contain a variety of chemicals that have been described as potentially hormone disrupting chemicals. Therefore, it is important to assess the internal exposure of these chemicals in humans. Within the 2nd Flemish Environment and Health Study (FLEHS II, 2007-2011), the human exposure to three classes of pollutants that are present in a wide variety of PCPs--i.e. polycyclic musks (galaxolide, HHCB and tonalide, AHTN in blood), parabens (urinary para-hydroxybenzoic acid, HBA) and triclosan (urinary TCS)--was assessed in 210 Flemish adolescents (14-15 years) and in 204 adults (20-40 years) randomly selected from the general population according to a stratified two stage clustered study design. The aim of this study was to define average levels of exposure in the general Flemish population and to identify determinants of exposure. Average levels (GM (95% CI)) in the Flemish adolescents were 0.717 (0.682-0.753) μg/L for blood HHCB; 0.118 (0.108-0.128) μg/L for blood AHTN; 1022 (723-1436) μg/L for urinary HBA and 2.19 (1.64-2.92) μg/L for urinary TCS. In the adults, levels of HBA were on average 634 (471-970) μg/L. Inter-individual variability was small for HHCB and AHTN, intermediate for HBA, and large for TCS. All biomarkers were positively associated with the use of PCPs. Additionally, levels of HHCB and AHTN increased with higher educational level of the adolescents. Both in adults and adolescents, urinary HBA levels were negatively correlated with BMI. We define here Flemish exposure values for biomarkers of PCPs, which can serve as baseline exposure levels to identify exposure trends in future biomonitoring campaigns.

Determinants of bisphenol A and phthalate metabolites in urine of Flemish adolescents

As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and different phthalate metabolites were analyzed, for the first time, in the urine of 210 adolescents in Flanders, Belgium. All chemicals had a detection frequency above 90%. For all compounds, except the sum of DEHP, highest levels were detected during spring. Average values for the Flemish adolescents were in an agreement with concentrations found in different international studies, all confirming the ubiquity of BPA and phthalate exposure. There was a significant correlation between BPA and the different phthalate metabolites (r between 0.26 and 0.39; p<0.01). Shared sources of exposure to BPA and phthalates, such as food packaging, were suggested to be responsible for this positive correlation. Different determinants of exposure were evaluated in relation to the urinary concentrations of these chemicals. For BPA, a significant association was observed with household income class, smoking and exposure to environmental tobacco smoke. For phthalates, the following significant associations were observed: age (MBzP), educational level of the adolescent (MBzP), equivalent household income (MnBP), use of personal care products (MnBP and MBzP), wall paper in house (MnBP and MBzP) and use of local vegetables (MnBP and MBzP).

Trace metals in blood and urine of newborn/mother pairs, adolescents and adults of the Flemish population (2007-2011)

The Flemish Centre for Environment and Health started with human biomonitoring in 2002 (FLEHS I: 2002-2006). The main goal of the second human biomonitoring cycle (FLEHS II: 2007-2011), was to determine mean values for a large number of pollutants in a representative sample of the general Flemish population. Values for Cd and Pb were updated, and a group of previously undetermined metals and metalloids (As, Mn, Cu and Tl) were included in some of the age groups. In this human biomonitoring program, three different age groups of the general Flemish population were monitored: 255 newborns and their mothers, 210 adolescents aged 14-15, and 204 adults between 20 and 40 years old. Trace elements were determined in cord blood and maternal blood of the mothers, in blood and urine of adolescents and in urine of adults. Determinants of life-style and personal factors were taken into account. The levels of trace elements in cord blood and maternal blood were for most elements at the lower end of the range found in literature. For Pb, As and Tl, a strong correlation (respectively r=0.43, 0.55 and 0.33; p<0.05) was found between levels in cord blood (respectively 8.6, 0.54 and 0.017 μg/L) and maternal blood (11.1, 0.64 and 0.028 μg/L), indicating that they are transported via the placenta from mother to fetus. The levels found in the adolescents and adults were compared with results from international biomonitoring studies, and were found to be in the same ranges. With the exception of Pb, all trace elements increased with increasing age group population. Finally, the results also showed that the levels of Cd and Pb in blood for this campaign (e.g. for Pb 8.6 and 14.8 μg/L in neonates and adolescents respectively) were lower compared to the first campaign (e.g. for Pb 14.7 and 21.7 μg/L in neonates and adolescents respectively), indicating a decrease over time. However, differences in sampling strategies might partially explain this observed trend.

Chapter 2F:The Flemish Environment and Health Study (FLEHS) – Second Survey (2007–2011): Establishing Reference Values for Biomarkers of Exposure in the Flemish Population

The second Flemish human biomonitoring survey (2007–2011) generated information on the distribution of biomarker values for a large number of environmental pollutants in a representative sample of the Flemish population. The study was implemented by the Flemish Centre of Expertise for Environment and Health, which was funded and steered by the Flemish government. From May 2008 to July 2009, 255 newborns and their mothers, 210 adolescents (14–15 years old) and 204 adults (20–40 years old) were recruited as a representative sample of the Flemish population. In all age groups, invitation letters, information brochures, letter of informed consent and self-administered questionnaires were distributed. The collected samples consisted of cord blood from the newborns, blood from the mothers, the adolescents and the adults, urine from the adolescents and the adults, and hair from the mothers. In addition to historical compounds (i.e. heavy metals, persistent chlorinated compounds, 1-hydroxy pyrene and t,t-muconic acid), new emerging pollutants were analyzed for the first time in individual samples from the Flemish population. Perfluorinated compounds and polycyclic musk compounds could be detected in all analyzed blood samples. Levels of brominated flame retardants were under the limit of quantification in most individual blood samples. Bisphenol A, metabolites of phthalates and para-hydroxybenzoic acid, a metabolite of parabens, could be detected in 90% or more of the urine samples. For metabolites of organophosphate pesticides, the highest detection frequency was observed for DMTP, detected in 90–95% of the individual urine samples. In addition, 2,5-DCP, a metabolite of para-dichlorobenzene, could be detected in over 80% of the individual urine samples. Margins of safety (MOS) were calculated by dividing the P90 obtained in FLEHSII by the available health based biomonitoring equivalants (BEs). MOS below 10 were found for toxicologically relevant arsenic, cadmium, lead, MeHg, HCB and phthalates.

Social distribution of internal exposure to environmental pollution in Flemish adolescents.

BACKGROUND Environmental justice research suggests that inequalities in the distribution of environmental exposure to chemical pollution systematically disadvantage the lower social strata of society. The effects of these inequalities on the human exposure to pollution are however to a large extend unknown. The purpose of this study is to assess social gradients in human biomonitoring results of a representative sample of Flemish adolescents. METHODS We investigate the associations between individual socioeconomic status (SES), measured by parental educational attainments, and internal body concentration of seven chemical compounds in biological samples of 1642 adolescents aged 14-15 in Flanders (Belgium): PCBs, HCB, DDE, lead, cadmium, benzene and PAHs. Social gradients in average and high exposure to these biomarkers were examined with geometric means and odds ratios (with 95% confidence intervals), using multiple regression models, controlling for covariates and confounders. RESULTS Depending on the (type of) pollutant, adolescents with a lower SES either have higher or lower internal concentrations. Chlorinated compounds (PCBs and pesticides HCB and DDE) are positively associated with SES (higher exposures for higher SES), while heavy metals (lead and cadmium) are negatively associated (higher exposures for lower SES). For metabolites of organic compounds (benzene and PAHs) we find no association with SES. Socially constructed factors, such as dietary and lifestyle habits, play an important role in these relations. CONCLUSIONS Our study suggests that the association between individual SES and the internal body concentration of exposure to environmental pollutants in Flemish adolescents is more complex than can be assumed on the basis of the environmental justice hypothesis.

Health effects in the Flemish population in relation to low levels of mercury exposure: From organ to transcriptome level

Due to possible health risks, quantification of mercury accumulation in humans was included in the Flemish biomonitoring programmes FLEHS I (2002-2006) and FLEHS II (2007-2011). The general objective of FLEHS I was to assess regional exposure levels in order to link possible differences in these internal exposure levels to different types of local environmental pressure. Therefore, Hg and MMHg (methylmercury) were only measured in pooled blood samples per region and per age class. In FLEHS II, mercury concentrations were measured in hair of each participant. About 200 adolescents and 250 mothers (reference group) and two times 200 adolescents (2 hotspots) were screened. The main objectives of the FLEHS II study were: (1) to determine reference levels of mercury in hair for Flanders; (2) to assess relations between mercury exposure and possible sources like fish consumption; (3) to assess dose-effect relations between mercury exposure and health effect markers. The results showed that mercury concentrations in the Flemish population were rather low compared to other studies. Mercury levels in the Flemish populations were strongly related to the age of the participants and consumption of fish. Significant negative associations were observed between mercury in hair and asthma, having received breast feeding as a newborn, age at menarche in girls, allergy for animals and free testosterone levels. Significant correlations were also observed between mercury in hair and genes JAK2, ARID4A, Hist1HA4L (boys) and HLAdrb5, PIAS2, MANN1B1, GIT and ABCA1 (girls).

Natural scientific complexity from a social scientific perspective: environment and health research and policymaking in Flanders (Belgium)

This paper discusses the relevance of a complexity approach to environment and health research. The approach is characterised by modesty, respect and transparency with regard to complexity of real world problems, and openness to a diversity of knowledge and opinion. The approach criticises the traditional interpretation of objectivity and emphasises the inter-subjectivist nature of science. The Centre of Expertise for Environment and Health (CEH), working directly for the Flemish government, is a good example of the relevance of the approach in environment and health research. It also exemplifies the need for a social science contribution. Moreover, it illustrates the complicatedness of such an endeavour in practice. The approach will not make work easier in all respects, but it will enhance the quality by respecting the complexity of real world problems.

The added value of a surveillance human biomonitoring program: The case of FLEHS in Flanders (Belgium)

Since 2002, the Flemish Government decided to carry out the Flemish Environment and Health Survey (FLEHS), an extended human biomonitoring (HBM) program, which is integrated in the environmental health policy. Through the FLEHS studies, a vast amount of data such as biomarkers of exposure and effect, exposure-effect associations, time trends and geographical differences, became available to the Flemish policy makers. In order to facilitate the policy interpretation, a phased action-plan was developed collaboratively by FLEHS researchers and policy makers. In this article we look back on more than 15 years of investments of the Flemish government in HBM and reflect on how this large scaled and challenging HBM-initiative contributed to shaping the environmental health policy in Flanders. We used the FLEHS I (2002-2006) and II (2007-2011) results on persistent organic pollutants (POPs) and the resulting policy actions as an example to illustrate the added value of HBM for policy making. Policy measures for POPs, including source-related regulation (e.g. further optimization and tightening of existing Flemish legislation on open fires), investment in monitoring networks and communication and awareness campaigns, are presented and the added value for environmental health policy is discussed. We also reflect on how HBM can support science and innovation in the environmental monitoring context. Finally, we describe what society can gain from HBM in terms of opportunities for (1) feeding the political and societal debate, (2) stimulating community involvement and (3) empowering participants and citizens. All together, the gained insights and phased action plan showed that next to compliance with high scientific standards, results of the Flemish human biomonitoring campaign could be translated in targeted policy actions even for chemicals that have since long been regulated.

Human biomonitoring from an environmental justice perspective: supporting study participation of women of Turkish and Moroccan descent

BackgroundEnvironmental justice research shows how socially disadvantaged groups are more exposed and more vulnerable to environmental pollution. At the same time, these groups are less represented and, thus, less visible in biomedical studies. This socioeconomic participation bias is a form of environmental injustice within research practice itself.MethodsWe designed, implemented and evaluated a targeted recruitment strategy to enhance the participation of socially disadvantaged pregnant women in a human biomonitoring study in Belgium. We focused on women of Turkish and Moroccan descent and developed a setup using personal buddies that enabled information transfer about study conditions in the pre-parturition period as well as support and follow-up with questionnaires in the post-parturition period.ResultsWe identified four barriers to the participation of women with a vulnerable social and ethnic background which were related to psychosocial and situational factors. Lack of trust in researchers and no perceived study benefits were important personal barriers; the complex study design and difficult self-administered questionnaires were equally significant barriers.ConclusionBy investing in direct, person-to-person contact with trusted buddies and supported by practical advice about cultural and linguistic sensitivity, it was possible to increase study participation of socially disadvantaged people. Above all, this required openness and flexibility in the mind-set of researchers so that study design and procedures could be better grounded in the experiences and circumstances of underprivileged groups.