Exposure of children to brominated flame retardants and heavy metals in Morocco: Urine and blood levels in association with global cytosine and adenine methylation

Kaoutar Chbihi; Aziza Menouni; Emilie Hardy; Matteo Creta; Nathalie Grova; An Van Nieuwenhuyse; Lode Godderis; Samir El Jaafari; Radu-Corneliu Duca

doi:10.1016/j.envint.2023.108409

Exposure of children to brominated flame retardants and heavy metals in Morocco: Urine and blood levels in association with global cytosine and adenine methylation

Environ Int. 2024 Jan:183:108409. doi: 10.1016/j.envint.2023.108409. Epub 2023 Dec 26.

Authors

Kaoutar Chbihi¹, Aziza Menouni², Emilie Hardy³, Matteo Creta⁴, Nathalie Grova⁵, An Van Nieuwenhuyse⁶, Lode Godderis⁷, Samir El Jaafari⁸, Radu-Corneliu Duca⁹

Affiliations

¹ Cluster of Competences on Health & Environment, Moulay Ismail University, Meknes 50000, Morocco; Center for Environment & Health, Department of Public Health and Primary Care, Faculty of Medicine, Katholieke Universiteit of Leuven, Leuven 3000, Belgium; Unit of Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Dudelange L-3555, Luxembourg. Electronic address: k.chbihi@edu.umi.ac.ma.
² Cluster of Competences on Health & Environment, Moulay Ismail University, Meknes 50000, Morocco; Center for Environment & Health, Department of Public Health and Primary Care, Faculty of Medicine, Katholieke Universiteit of Leuven, Leuven 3000, Belgium.
³ Unit of Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Dudelange L-3555, Luxembourg.
⁴ Center for Environment & Health, Department of Public Health and Primary Care, Faculty of Medicine, Katholieke Universiteit of Leuven, Leuven 3000, Belgium; Unit of Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Dudelange L-3555, Luxembourg.
⁵ Immune Endocrine Epigenetics Research Group, Department of Infection and Immunity-Luxembourg Institute of Health, Esch-Sur-Alzette L-4354, Luxembourg; UMR Inserm 1256 nGERE, Nutrition-Génétique et exposition aux risques environnementaux, Institute of Medical Research (Pôle BMS) - University of Lorraine, B.P. 184, Nancy 54511, France.
⁶ Center for Environment & Health, Department of Public Health and Primary Care, Faculty of Medicine, Katholieke Universiteit of Leuven, Leuven 3000, Belgium; Department of Health Protection, Laboratoire National de Santé (LNS), Dudelange L-3555, Luxembourg.
⁷ Center for Environment & Health, Department of Public Health and Primary Care, Faculty of Medicine, Katholieke Universiteit of Leuven, Leuven 3000, Belgium; IDEWE, External Service for Prevention and Protection at Work, Heverlee 3001, Belgium.
⁸ Cluster of Competences on Health & Environment, Moulay Ismail University, Meknes 50000, Morocco.
⁹ Center for Environment & Health, Department of Public Health and Primary Care, Faculty of Medicine, Katholieke Universiteit of Leuven, Leuven 3000, Belgium; Unit of Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Dudelange L-3555, Luxembourg. Electronic address: radu.duca@lns.etat.lu.

PMID: 38185044
DOI: 10.1016/j.envint.2023.108409

Abstract

Persistent pollutants, namely brominated flame retardants (BFRs) and heavy metals, are compounds that are added to a wide range of products and materials for preventing ignition, increasing the functionality of materials or improving their performance, e.g. electric conductivity. The exposure of children might consequently be inferred, through indoor dust and hand-to-mouth or toy-chewing behaviors. The current study is aimed at assessing the exposure of Moroccan children to BFRs and heavy metal elements, and evaluating their associations with global DNA methylation. First, parents responded to a questionnaire pertaining to children's lifestyle, then blood and urine samples were collected from (n = 93) children aged between 5 and 11 years for biomonitoring and DNA methylation analysis. BFRs were detected in 54.84% of samples with a median concentration of 0.01 nmol/mL (range: 0.004-0.051 nmol/mL) while metal elements were detected in more than 90% of samples. BFRs showed no variations with global DNA methylation, unlike metal elements, which revealed significant associations with global DNA methylation markers, namely 5-mC, 5-hmC and N⁶-mA levels. Moroccan children may be exposed to flame retardants and heavy metals through several routes. Further research is required to assess the exposure and the health impacts of environmental pollutants and ultimately protect the Moroccan population by the prevention of adverse health effects.

Keywords: Children; DNA methylation; Flame retardants; Heavy metals; Human biomonitoring; Morocco.

MeSH terms

Adenine / analysis
Air Pollution, Indoor* / analysis
Child
Child, Preschool
Dust / analysis
Environmental Exposure / analysis
Environmental Monitoring
Environmental Pollutants* / analysis
Flame Retardants* / analysis
Halogenated Diphenyl Ethers / analysis
Humans
Hydrocarbons, Brominated* / analysis
Metals, Heavy* / analysis
Morocco

Substances

Flame Retardants
Halogenated Diphenyl Ethers
Environmental Pollutants
Dust
Metals, Heavy
Adenine
Hydrocarbons, Brominated