Ann Colles

The extensive production and use of per- and polyfluoroalkyl substances (PFAS) over recent decades have resulted in their pervasive distribution in environmental compartments worldwide. PFAS concentrations in soil and biota near fluorochemical manufacturing facilities tend to be typically higher near hotspots, which suggests that the consumption of home-produced foods near such hotspots most likely results in higher human exposure. One prominent European hotspot is located near the 3M fluorochemical production facility in Zwijndrecht (Belgium), where the relative contributions of different exposure pathways remain insufficiently characterised. This study therefore aimed to assess the PFAS concentrations and compositional profiles in serum, dwellings and gardens of teenagers residing near this hotspot. Serum samples from teenagers, along with multiple environmental matrices (i.e., soil, compost, vegetables/fruits/nuts, chicken eggs, rainwater and indoor house dust) were analysed for 21 selected PFAS. Additionally, potential determinants of PFAS occurrence and distribution across matrices were investigated using detailed questionnaire data. We found perfluorooctane sulfonic acid (PFOS) to be the predominant compound in both soil and serum, while perfluorobutanoic acid (PFBA) was most dominant in rainwater, compost, house dust and pods. Perfluorobutane sulfonic acid (PFBS) was most abundant in fruits and chicken eggs, while perfluorododecanoic acid (PFDoDA) was predominant in rooting vegetables and nuts. N-methylperfluorooctane sulfonamidoacetic acid (MePFOSAA) was the dominant compound in fruiting, stem, and leafy vegetables. These results indicate differences in accumulation pathways among the different media and/or differences in affinities of different PFAS in the matrices. Additionally, several environmental and behavioural factors were identified as determinants for PFAS in soil, compost, tree fruits, fruiting vegetables, chicken eggs and house dust, providing insight into potential drivers of exposure variability. The most important factors were related to the soil characteristics, the composting of grass and weeds, the chicken feed (i.e., bread, commercial feed), the type and frequency of ventilation and the frequency of cleaning.

Background/Objectives: Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants that accumulate in humans through everyday exposure pathways, raising concern about long-term metabolic health effects in exposed populations. This study aimed to characterize PFAS-associated serum metabolic alterations in a Flemish population residing within a 3 km radius of a PFAS production facility using untargeted metabolomics and lipidomics. Methods: A cohort of 82 adults was stratified into high-exposure (n = 41, median total PFAS = 162.0 ng/mL) and low-exposure (n = 41, median total PFAS = 7.2 ng/mL) groups. Serum metabolic profiling was performed using four liquid chromatography–high-resolution mass spectrometry (LC-HRMS)-based platforms. Univariate and multivariate statistics were conducted to identify metabolites that were differentially expressed between both exposure groups. Results: The analysis revealed 38 altered metabolites. Overall, high PFAS exposure was characterized by upregulation of phosphatidylglycerols (PG), phosphatidylinositols, phosphatidylethanolamines (PE), and triacylglycerols (TG) and downregulation of sphingomyelins, with differential regulation of ceramides, hexosylceramides (HexCer), and phosphatidylcholines. Glycerophospholipid metabolism as well as sphingolipid metabolism pathways were identified as perturbed. Seven lipids and one amino acid showed weak-to-strong correlations (|r|= 0.23–0.61) with PFAS levels. A panel of five metabolites was selected to explore whether they collectively form a potential metabolic signature associated with PFAS exposure. This panel, including L-aspartic acid, PG 18:0_18:2, HexCer (d18:1/14:0), PE 16:0_18:3, and TG 16:0_20:5_22:6, showed moderate discrimination between residents with high and low PFAS levels (area under the curve, AUC = 0.753). Conclusions: This study identifies coordinated lipid metabolic changes associated with PFAS exposure and highlights a small, exploratory metabolite panel that may provide complementary insight into the biological effects of PFAS.

Contrary to the initial hypothesis, Flemish adolescents who reported consuming organic food at least 7.5 times per week did not exhibit reduced internal exposure to the tested recently used pesticides. After adjustment for gender, age, country of origin, socioeconomic status, body mass index, consumption of high-fat foods and foods linked to organic food consumption, and concerning organochlorine derivatives and lead, additional adjustment for the duration of breastfeeding expressed in weeks, they displayed slightly elevated internal exposure to organochlorine derivatives, lead, methyl arsenate, and toxic relevant arsenic. A comparison was also made between the correlation of internal exposure to pollutants with the frequency of organic food consumption on one hand and the total consumption of equivalent products from all sources on the other. Regarding potatoes, vegetables, and fruits, no clear trends were observed. Regarding eggs, there was a trend towards higher internal exposures with organic food consumption, significant for trans-nonachlor, PCB118, and 2,4-dichlorophenoxyacetic acid, and marginally significant for glyphosate. For dairy, there was a trend towards higher internal exposures with organic food consumption, significant for perfluorononanoic acid and marginally significant for PCB153. Regarding nuts and seeds, the higher internal exposure to dichlorophenoxyacetic acid and the lower exposure to 3-phenoxybenzoic acid were marginally significant, while there was also a trend towards higher internal exposure to other pollutants with organic food consumption, significant for PCB118, PCB153, and sum PCBs, and marginally significant for trans-nonachlor. Concerning breakfast cereals and muesli, no clear trends were observed.

Early puberty has been found to be associated with adverse health outcomes such as metabolic and cardiovascular diseases and hormone-dependent cancers. The decrease in age at menarche observed during the past decades has been linked to an increased exposure to endocrine-disrupting compounds (EDCs). Evidence for the association between PFAS and phthalate exposure and menarche onset, however, is inconsistent. We studied the association between PFAS and phthalate/DINCH exposure and age at menarche using data of 514 teenagers (12 to 18 years) from four aligned studies of the Human Biomonitoring for Europe initiative (HBM4EU): Riksmaten Adolescents 2016–2017 (Sweden), PCB cohort (follow-up; Slovakia), GerES V-sub (Germany), and FLEHS IV (Belgium). PFAS concentrations were measured in blood, and phthalate/DINCH concentrations in urine. We assessed the role of each individual pollutant within the context of the others, by using different multi-pollutant approaches, adjusting for age, age- and sex-standardized body mass index z-score and household educational level. Exposure to di(2-ethylhexyl) phthalate (DEHP), especially mono(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), was associated with an earlier age at menarche, with estimates per interquartile fold change in 5OH-MEHP ranging from −0.34 to −0.12 years in the different models. Findings from this study indicated associations between age at menarche and some specific EDCs at concentrations detected in the general European population, but due to the study design (menarche onset preceded the chemical measurements), caution is needed in the interpretation of causality.

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants of public health concern. Multiple biological mechanisms have been hypothesized to contribute to PAHs-associated adverse health effects. Little is known about the impact of PAHs on endocrine stress and inflammation in adolescence. We examined 393 Flemish adolescents (14–15 years) cross-sectionally, measured urinary concentrations of hydroxylated naphthalene, fluorene, phenanthrene and pyrene metabolites, and calculated the sum of all measured metabolites. We determined hair cortisol concentration (HCC) as endocrine stress biomarker, leucocyte counts and neutrophil–lymphocyte ratio (NLR) in peripheral blood as inflammatory biomarkers, and urinary 8-oxo-7,8-dihydro-2’-deoxyguanosine (8-oxodG) concentration as oxidative stress biomarker. Exposure–response associations were analyzed by multiple regression, adjusted for a priori selected covariates. A doubling of 1-hydroxypyrene concentration was associated with a factor of 1.13 (95% CI: 1.03, 1.24) increase in HCC and a factor of 1.07 (95% CI: 1.02, 1.13) increase in 8-oxodG. Doublings of 2- and 3-hydroxyphenanthrene concentrations were associated with a factor of 1.08 (95% CI: 1.02, 1.14) and 1.06 (95% CI: 1.00, 1.12) increase in 8-oxodG, respectively. Doubling of 2-hydroxyphenanthrene and of the sum of 2- and 3-hydroxyfluorene was associated with, respectively, a factor of 1.08 (95% CI: 1.02, 1.14) and 1.06 (95% CI: 1.01, 1.13) increase in NLR. Our results indicate the glucocorticoid pathway as a potential target for PAH exposure in adolescents and suggest oxidative stress, endocrine stress, and inflammation in adolescence as underlying mechanisms and early markers for PAH-related adverse health effects.

Human biomonitoring (HBM) monitors levels of environmental pollutants in human samples, which often is a topic of concern for residents near industrially contaminated sites (ICSs). Around an ICS area in Menen (Belgium), including a (former) municipal waste incinerator and a metal recovery plant, increasing environmental concentrations of dioxins and polychlorinated biphenyls (PCBs) were observed, causing growing concern among residents and authorities. The local community succeeded in convincing the responsible authorities to investigate the problem and offer research funding. Persistent organic pollutants (POPs) were measured in two consecutive HBM studies (2002–2006 and 2010–2011), in the context of the Flemish Environment and Health Study (FLEHS), as well as in soil and locally produced food. Meanwhile, local authorities discouraged consumption of locally produced food in a delineated area of higher exposure risk. Ultimately, HBM and environmental data enabled tailored dietary recommendations. This article demonstrates the usefulness of HBM in documenting the body burdens of residents near the ICS, identifying exposure routes, evaluating remediating actions and providing information for tailored policy strategies aiding to further exposure reduction. It also highlights the role of the local stakeholders as an example of community-based participatory research and how such an approach can create societal support for research and policy.

Communicating individual human biomonitoring results to study participants has been the subject of debate for some time. This debate is dominated by ethical considerations from a researchers’ perspective on whether or not to communicate, thereby overlooking more practice-based questions from a participants’ perspective on what and how to communicate. We conducted a small scale follow-up study based on eleven face-to-face interviews with mothers participating in the third cycle of the Flemish Environment and Health Study (FLEHS III 2012–2015) to investigate how they experienced and interpreted individual biomonitoring results. Key findings indicate that respondents were generally satisfied with participating in the biomonitoring study, but the report-back process especially lacked contextualized information and interactive communication options to better comprehend and cope with personal results. These findings also argue in favor of a more tailored approach in which report-back methods, formats and content are diversified according to the type of results and the preferences of participants. A reflexive research practice with active engagement in follow-up research is crucial to improve participants’ understanding and use of personal biomonitoring results.