Serum PFAS levels measured in the general population of Kinshasa, Democratic Republic of Congo, in 2022-2023.

Per- and polyfluoroalkyl substances (PFAS) are synthetic compounds widely used for their remarkable chemical properties, but they are raising growing health concerns. While biomonitoring data exist for North America, Europe, and the Asia-Pacific region, evidence from Sub-Saharan Africa was scarce. The objective of the present study is to measure PFAS contamination in volunteers recruited in Kinshasa, capital of the Democratic Republic of Congo. We assessed serum PFAS concentrations in 136 adults (63.2% men and 36.8% women, median age: 33.5 years) recruited in 2022 and 2023 in Kinshasa, Democratic Republic of Congo. Fourteen PFAS were measured using liquid chromatography-mass spectrometry (Agilent 1290 Infinity II LC/Agilent 6495 LC/TQ MS). Only five compounds were quantified in more than 10% of samples: perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), linear perfluorooctane sulfonate (linPFOS), and total PFOS (totPFOS). Median serum levels were 0.166 ng/mL (PFNA), 0.270 ng/mL (PFHxS), 0.384 ng/mL (PFOA), 0.675 ng/mL (linPFOS), and 1.70 ng/mL (totPFOS). Compared with international data, PFAS levels in our population were among the lowest reported in the past decade. Only 0.7% of participants exceeded the German HBM-I value for PFOA while no volunteer exceeded this threshold for linPFOS. These HBM-I values are concentrations below which no health effect are. These findings suggest relatively low health risks related to PFAS in Kinshasa compared to Western and Asian countries. In the DRC context, where risk associated to other pollutants such as triclosan, lead or DDT metabolites is higher, resources may be better directed toward these more pressing threats.