Background contamination of perfluoralkyl substances in a Belgian general population
Introduction
Perfluoroalkyl substances (PFASs) are man-made chemicals that have been widely used since the mid-20th century in many industrial applications as well as in everyday life consumer products, due to their unique oil and water repellant properties as well as their high thermal and chemical stabilities. They have been employed among others as surfactants in cleaning agents or in firefighting foams, as surface protectors in carpet, textiles, upholstery, food packaging, and non-stick cookware (ATSDR, 2018; Kissa, 2001; Lindstrom et al., 2011). They have also been useful in the automotive and aerospace industries, in building construction, in personal care products, etc (OECD, 2006; Wang et al., 2013). Due to their persistence, their ubiquity in the environment and their health concerns, a phase out has been initiated from 2000 by some American industries (Renner, 2008), and subsequent restrictions were implemented mainly in United States (US EPA, 2015) followed few years later by the European countries (Schröter-Kermani et al., 2013). The impact of these production and use reductions on the human exposure was confirmed by the decreasing temporal trend of the serum levels from worldwide general populations reported from 2000 to 2010 for some PFASs, mainly perfluorooctane sulfonate (PFOS) and to a lesser extend perfluorooctanoic acid (PFOA), (Berg et al., 2014; Glynn et al., 2012; Kato et al., 2011; Schoeters et al., 2017; Schröter-Kermani et al., 2013; Toms et al., 2014; Yeung et al., 2013). Nevertheless in some countries (i.e. China) where PFASs are still used and produced (Li et al., 2017; Xie et al., 2013), higher PFAS serum levels would be expected compared to other populations which might be associated with several health effects such like a decline renal function, hepatotoxicity or hypertension (Bao et al., 2017; Nian et al., 2019; Wang et al., 2019).
There are different reasons why actual human biomonitoring focused on PFAS contamination is needed so far. Firstly, decrease of PFOS exposure related to the implementation of last regulations still deserves to be confirmed (i.e. inclusion of PFOS in the Annex B of the Stockholm Convention, inclusion of PFOA and other perfluorinated carboxylic acids on the candidate list of substances of very high concern within the European REACH program). Secondly, for other PFAS than PFOS and PFOA, the temporal trends of serum levels seemed to vary according to the perfluorinated chemicals, the time and the country where the study took place. For instance, upward trends have been reported for perfluorononanoic acid (PFNA), perfluorohexanesulfonate (PFHxS) and perfluorobutanesulfonate (PFBS) in Sweden between 1996 and 2010 (Glynn et al., 2012) or in United States between 1999 and 2008 (Kato et al., 2011), while no clear trend was observed for PFNA in Germany during the two last decades (Schröter-Kermani et al., 2013). Then, human contamination data concerning short chain PFAS such as PFBS, a recently used as an alternative of restricted PFASs (Wang et al., 2013) are still lacking. And finally, other fluorinated substances like fluorotelomers or functionalized perfluoropolyethers demonstrated to be potential precursor of PFOS and/or PFOA are until today not regulated (Wang et al., 2013).
In addition, if food intake and especially seafood product consumption was considered for a long time as the main contributor to the human exposure (Haug et al., 2011; Vestergren and Cousins, 2009), other food items and other routes of exposure have been demonstrated to substantially contribute to the total exposure (Bartolomé et al., 2017; Berg et al., 2014; de la Torre et al., 2019; D’Hollander et al., 2015; Fraser et al., 2012,2013; Klenow et al., 2013; Shoeib et al., 2011). For instance, the contribution of fruits to the total dietary intake could vary from 20 to 93 % depending on the PFAS considered, the country where the assessment was carried out, or the population targeted (adults or children) (D’Hollander et al., 2015). Inhalation or ingestion of house dust were estimated to represent from 1 to 13 % of the dietary exposure of PFAS, these percentages could even increase up to 50 % for toddlers (de la Torre et al., 2019; Shoeib et al., 2011). Definitely, the contributions of these currently known exposure routes have not been yet fully determined, would be country or region dependent, and would likely not account for the totality of the human exposure suggesting that other sources have not yet been clearly identified (Ericson et al., 2008; Ingelido et al., 2010; Jain, 2014; Kärrman et al., 2009; Kato et al., 2011). Thus further studies are needed to better characterize the current sources of exposure to PFASs and their contribution to the global exposure.
The PFAS exposure of the general population has been well documented since 2000′s but only a few dozen recent data on blood concentration in Europe, produced after 2010, are up to now available. In Belgium, Flanders (Northern part of Belgium) was one of the European pioneers by developing and implementing HBM programs since 2002. Indeed the Flemish Environment and Health Studies (FLESH) have covered 3 distinct time periods from 2002 and 2015, and have included more than 5800 participants (Reynders et al., 2017; Schoeters et al., 2017). Among the fifty hazardous chemicals included, PFASs were measured in different population categories in the 2 last campaigns (2007–2011 and 2012–2015) thus producing recent trends for these persistent organic pollutants in the Northern half of Belgium. The opposite situation is occurring in Wallonia (Southern part of Belgium) where the Walloon policy-makers are only beginning to invest in HBM to assess environment health and support policy actions. Nevertheless, few small-scale HBM studies were already locally carried out in Wallonia (Hoet et al., 2013; Koppen et al., 2019; Pirard et al., 2012, 2014,2018) but none were so far focused on PFASs.
Thus, the aims of the present study were to assess the background PFAS contamination in the general Walloon population, and to explore the contribution of food consumption and lifestyle habits as well as some demographic characteristics on the current PFAS exposure in Wallonia. For these purposes, serum samples collected during a previous study from 242 people older than 18 years old and living in the Province of Liege (Pirard et al., 2018) were analyzed for 8 perfluorinated carboxylic acids and 3 perfluorinated alkyl sulfonates, including short- and long-chain PFASs. The answers to the questionnaire related to food habits, life styles and home environment were also included in statistical models to identify some predictors of PFAS exposure.
Section snippets
Study participants
In 2015, 252 participants aged from 18 to 76 years and living in the Province of Liege were recruited through the Provincial High Schools and Provincial offices, to obtain a non-occupationally exposed population homogeneously distributed between gender, age classes (18–29, 30–39, 40–49, 50–59, >60 years), and the rural or urban character of their residence place. They signed an informed consent, provided a blood sample in clot activator tubes (without gel), and answered a questionnaire about
Levels of exposure
Among the PFASs monitored in the serum of our participants, PFBS, PFPeA, PFHxA, and PFDoA were never detected in any of the 242 samples. Although these compounds have usually been rarely positively measured in the general population (Cariou et al., 2015; Ericson et al., 2007; Kato et al., 2011; Lee et al., 2017; Long et al., 2015; Schröter-Kermani et al., 2013), the human exposure to PFBS, PFPeA and PFHxA was expected because these shorter-chain are used to replace long-chain PFASs as
Conclusion
The human background contamination of PFASs was measured for the first time in Wallonia (Southern part of Belgium) by determining the levels of 11 PFASs in 242 serum samples collected in 2015 from individuals living within the Province of Liege. For all participants, at least 4 PFASs were detected simultaneously, with levels close to those recently reported in other European or North American countries, but substantially lower than levels measured in the North of Belgium. However, only half of
Ethical approval
This protocol was approved by the Hospital Faculty Ethics Committee of the University of Liege (B707201422894).
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
This study was financially supported by the Walloon Region as part of the grant 18/16857.
References (77)
- et al.
Human biomonitoring assessment values: approaches and data requirements
Int. J. Hyg. Environ. Health
(2011) - et al.
New HBM values for emerging substances, inventory of reference and HBM values in force, and working principles of the german human biomonitoring commission
Int. J. Hyg. Environ. Health
(2017) - et al.
Gender-specific associations between serum isomers of perfluoroalkyl substances and blood pressure among chinese: isomers of C8 health project in China
Sci. Total Environ.
(2017) - et al.
Perfluorinated alkyl substances in spanish adults: geographical distribution and determinants of exposure
Sci. Total Environ.
(2017) - et al.
Maternal serum concentrations of per- and polyfluoroalkyl substances and their predictors in years with reduced production and use
Environ. Int.
(2014) - et al.
Perfluoroalkyl acid (PFAA) levels and profiles in breast milk, maternal and cord serum of french women and their newborns
Environ. Int.
(2015) - et al.
Polybrominated diphenyl ethers and perfluorinated alkyl substances in blood serum of New Zealand adults, 2011–2013
Chemosphere
(2018) - et al.
First assessment of population exposure to perfluorinated compounds in Flanders, Belgium
Chemosphere
(2012) - et al.
Occurrence of perfluorinated alkylated substances in cereals, salt, sweets and fruit items collected in four european countries
Chemosphere
(2015) - et al.
PFOS levels in the blood and liver of a small insectivorous songbird near a fluorochemical plant
Environ. Int.
(2007)
Current exposure of italian women of reproductive age to PFOS and PFOA: a human biomonitoring study
Chemosphere
Occurrence and human exposure assessment of perfluorinated substances in house dust from three european countries
Sci. Total Environ.
Association between organohalogenated pollutants in cord blood and thyroid function in newborns and mothers from belgian population
Environ. Pollut.
Perfluorinated chemicals in blood of residents in Catalonia (Spain) in relation to age and gender: a pilot study
Environ. Int.
Polyfluorinated compounds in dust from homes, offices, and vehicles as predictors of concentrations in office workers’ serum
Environ. Int.
Perfluorinated chemicals in blood serum of inhabitants in Central Poland in relation to gender and age
Sci. Total Environ.
Perfluoroalkylated acids in the eggs of great tits (Parus major) near a Fluorochemical Plant in Flanders, Belgium
Environ. Poll.
Characterisation of human exposure pathways to perfluorinated compounds — comparing exposure estimates with biomarkers of exposure
Environ. Int.
Evaluation of biochemical effects related to perfluorooctane sulfonic acid exposure in organohalogen-contaminated great tit (Parus major) and blue tit (Parus Caeruleus) nestlings
Chemosphere
Perfluorooctanesulfonate and perfluorooctanoic acid exposures of the italian general population
Chemosphere
Contribution of diet and other factors to the levels of selected polyfluorinated compounds: data from NHANES 2003–2008
Int. J. Hyg. Environ. Health
Perfluoroalkyl acids in serum of korean children: occurrences, related sources, and associated health outcomes
Sci. Total Environ.
Relationship between dietary exposure and serum perfluorochemical (PFC) levels—a case study
Environ. Int.
Mothers and children are related, even in exposure to chemicals present in common consumer products
Environ. Res.
Serum concentrations of per- and poly-fluoroalkyl substances and factors associated with exposure in the general adult population in South Korea
Int. J. Hyg. Environ. Health
Isomers of perfluorooctanesulfonate (PFOS) in cord serum and birth outcomes in China: guangzhou birth cohort study
Environ. Int.
Blood serum concentrations of perfluorinated compounds in men from greenlandic inuit and european populations
Chemosphere
Food intake and serum persistent organic pollutants in the greenlandic pregnant women: the ACCEPT sub-study
Sci. Total Environ.
The effect of ongoing blood loss on human serum concentrations of perfluorinated acids
Chemosphere
Pilot study on the perfluorooctanesulfonate and perfluorooctanoate exposure of the german general population
Int. J. Hyg. Environ. Health
Liver function biomarkers disorder is associated with exposure to perfluoroalkyl acids in adults: isomers of C8 health project in China
Environ. Res.
Urinary levels of bisphenol a, triclosan and 4-Nonylphenol in a general belgian population
Environ. Int.
Hair mercury and urinary cadmium levels in belgian children and their mothers within the framework of the COPHES/DEMOCOPHES projects
Sci. Total Environ.
The current environmental levels of endocrine disruptors (Mercury, cadmium, organochlorine pesticides and PCBs) in a belgian adult population and their predictors of exposure
Int. J. Hyg. Environ. Health
The added value of a surveillance human biomonitoring program: the case of FLEHS in Flanders (Belgium)
Int. J. Hyg. Environ. Health
Food risk assessment for perfluoroalkyl acids and brominated flame retardants in the french population: results from the second french total diet study
Sci. Total Environ.
Elevated levels of PFOS and PFHxS in firefighters exposed to aqueous film forming foam (AFFF)
Environ. Int.
Three cycles of human biomonitoring in flanders − time trends observed in the flemish environment and health study
Int. J. Hyg. Environ. Health
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