Polybrominated diphenyl ethers in car dust in Nigeria: Concentrations and implications for non-dietary human exposure

• Car dust samples from Nigeria were tested for the presence of common PBDEs.
• Target analytes comprise 7 PBDE congeners.
• Presence of target analytes was confirmed in car dust samples.
• Human exposure estimates were determined and found lower than in other regions.
• First set of data to be generated on concentrations and daily intake estimates of PBDEs in car dust in Nigeria.

In the present study, the levels of polybrominated diphenyl ethers in car dust samples collected from 12 randomly selected cars in Nigeria were measured, and the daily intake via dust ingestion were estimated for four categories of individuals. PBDEs were extracted and analyzed using ultra-sonication extraction and gas chromatography electron impact ionization mass spectrometry (GC-EIMS), respectively. The concentrations of ∑7PBDEs ranged from 159 to 736 ng g− 1 dry weight. BDE-209 was found to be the most prevalent congener with a total of 2130 ng g− 1, contributing up to 47% of the total congener values (4554 ng g− 1) and the other congeners contributed 53%. The mean and median concentrations of detected congeners ranged from 65 to 137 and 14 to 127 ng g− 1 dry weight, respectively. BDE-47 was detected in all the dust samples at a detection frequency of 100%, and this was followed by BDE-209 with 92%. The daily intake (DI) was estimated using concentrations corresponding to 5th percentile, median, and 95th percentile. The estimated DI was highest for professional drivers at 0.12 ng kg− 1 bw day− 1 and this was followed by toddlers (0–3 years) at 0.09 ng kg− 1 bw day− 1 while DI estimate of 0.01 ng kg− 1 bw day− 1 was determined for children (4–18 years) and adults (> 19 years). PBDEs daily intake rates from car dust estimated in the present study are way below the USEPA reference dose (RfD) for oral exposure to PBDEs 47, 99, 153, and 209 of 100, 100, 200, and 7000 ng kg bw day− 1