Polybrominated diphenyl ethers (PBDEs) are a group of organobromine compounds that are used as flame retardants in many commonly used products. Their presence has been confirmed in various environmental matrices. Their usage in numerous consumer products has lent credence to their ability to retard flammable gas formation, hence their ubiquitous nature in the environment. PBDEs have been described as endocrine disrupting chemicals because of their interference with the endocrine system function in fish and other terrestrial animals. In spite of the progress in research over the years on PBDEs, full understanding of the environmental behaviour and fate of this contaminant is still elusive. In this review, sources by which PBDEs enter the environment have been evaluated in conjunction with their levels, as well as their toxicity, and the transformation and transport of PBDEs in various environmental compartments. This provides a better understanding of the behaviour of these emerging environmental contaminants within the environment. While acknowledging the numerous studies that have been conducted on the environmental contamination by PBDEs, emerging issues and data gaps have been identified.

This study determined concentration levels of polybrominated diphenyl ethers (PBDEs) in sediment samples collected from Jukskei River in South Africa. Final extracts, after concentration and dilution to 200 μL were analyzed by injecting 1 μL in the GC-ECD and GC-MS. Results obtained showed good recoveries (73%-114%, with RSD < 17%). The concentrations of ∑PBDEs in sediment for the seven sampling sites ranged from 0.92 to 6.76 ng g(-1) dry weight and total PBDEs with a total BDE sum of 23.85 ng g(-1) dry weights. Concentrations of PBDEs obtained in the present study are significantly lower than the values reported from developed countries.

Brominated flame retardants (BFRs) are considered to be environmental pollutants due to their toxicity, persistence and ubiquity in the environment. Little information is known about the presence of brominated flame retardants in South Africa's water systems. Therefore, this study examined and compared different extraction methods (liquid-liquid (LL) vs. solid phase (SP) for water, Soxhlet extraction (SE) vs. ultrasonic for sediment) for extraction efficiencies in the determination of polybrominated diphenyl ethers (PBDEs) and polybrominated biphenyls (PBBs) in water and sediment from Jukskei River. Clean-up of sample extracts was performed using disposable Pasteur pipettes containing neutral, acidified and basic silica gel. Final extracts, after concentration and dilution to 200 μL were analyzed by injecting 1 μL in the GC-ECD and GC-MS. Results obtained showed good recoveries for most of the tested analytes in water; for LLE, values ranged between 80.5 ± 10.22% and 126.6 ± 1.94%; SPE, 70.41 ± 2.01%-124.78 ± 3.78% (n = 3) and for sediment (73-114%, with an RSD <17%) using SE. The ultrasonic extraction method gave less than 50% recovery for most of the congeners. The concentrations of the BFRs in water samples were less than the detection limit while the concentrations in sediment ranged from 1.95 to 36.61 ng g(-1) dry weight for Σ(11) BFRs. Dichloromethane and n-hexane : acetone (2 : 1, v/v) gave optimum value of recovery for water and sediment respectively.

Background: The selection of soil fraction is an important influencing factor to accurately determine human exposure risk to toxic chemicals in the environment. The present study evaluated the concentrations of prevalent polybrominated diphenyl ethers (PBDEs) in different size fractions of soil from a landfill site and the factors that influence their distribution in the soils. Method: Samples were fractionated into size fractions; between 150-250 and 45-150 μm (after initial sieving through a 250 μm sieve) and, thereafter, PBDEs were extracted using a mixture of toluene-dichloromethane and subsequently cleaned with a multilayer silica gel/Pesticarb/sodium sulphate column and analysed using GC-MS. Results: The sum of seven PBDE congeners (BDE-28,-47,-100,-99,-154,-153 and-183) ranged from 7.08 to 10.8 ng g −1 with a total median of 7.32 ng g −1 , and from 7.00 to 8.77 ng g −1 with a total median of 7.21 ng g −1 , corresponding to size fractions 150-250 μm and 45-150 μm, respectively. BDE-183 was predominant in both soil fractions. A significant correlation was observed between ∑ 7 PBDEs concentrations and total organic carbon (TOC), particularly for particle size 150-250 μm (r 2 = 0.829, p < 0.05). Conclusion: The study revealed that PBDE concentrations did not automatically increase with decreasing particle size, and as such, PBDE-treated consumer goods and consequent abrasions of flame retardant-containing materials could be likely sources. The study also clarified that selecting soil fractions arbitrarily for exposure risk assessment may lead to inconclusive results. The study results, therefore, have important inferences for estimating flame retardant chemical exposure.