Perfluoroalkyl substances (PFAS) are a group of persistent grease and water-repellent chemicals widely used in consumer products such as food packaging, clothing, and furniture. We are all exposed to PFAS through contaminated food and water as well as dust from treated materials. PFAS are transferred across the placenta and into breast milk, thereby causing peak exposures in infancy. Research has shown that PFAS may damage the immune system with early infancy seemingly being the most decisive time of exposure. A well-functioning immune system is essential for human life, and even minor damages can have major effects on the immune system’s ability to fight off infectious pathogens that we are continuously exposed to. In low-income countries with poor living conditions and inadequate access to clean water, food and health care, the consequences of reduced immune function may be particular severe.
Purpose
We have previously showed that increasing serum-PFAS concentrations were associated with increased risk of morbidity and decreased measles-specific antibody concentrations after vaccination among Guinean infants. In addition, we saw that PFAS exposure was associated with decreased measles-specific antibody concentrations before vaccination, indicating that PFAS affects either the transfer of maternal antibodies from mother to child or the rate at which the antibodies decline after birth. However, we did not measure PFAS concentrations among the mothers, which made it difficult to interpret these findings. Regulators have called for more PFAS studies having infectious disease and vaccine response endpoints, studies examining different types of PFAS and studies conducted on different populations. Thus, the aim of the proposed project is to investigate the effect of pre- and postnatal PFAS exposure on morbidity as well as measles antibody concentrations before and after vaccinations among West African infants and their mothers.
Method
This observational study is based on blood samples and background information from infants in Burkina Faso and Guinea-Bissau. Half the children were vaccinated against measles at inclusion (4-7 months), and all children were vaccinated at nine months. Blood samples were collected at inclusion, nine, and 15-24 months, and from their mothers at inclusion. The mothers were interviewed about infant morbidity. Measles antibodies was measured in all blood samples. We have previously analyzed serum from 200 Guinea-Bissau infants for PFAS, and we will further analyze serum from 200-250 Burkina Faso infants and their mothers for PFAS.
Project period
1/7 2021 – 31/12 2023
First results are expected to be out in 2024
Collaboration and funding
The project is funded by the Danish Health Foundation (Helsefonden)