Increasing Trends of Legacy and Emerging Organic Contaminants in a Dated Sediment Core From East-Africa

• DOI: 10.3389/fenvs.2021.805544
• Publication Date: 2022-01-07T05:21:25Z
• Authors: Maja Nipen; Rolf David Vogt; Pernilla Bohlin-N...; Katrine Borgå; Eliezer Brown Mwa...; Anders Røsrud Borgen; Martin Schlabach; Guttorm Christensen; Aviti John Mmochi; Knut Breivik
• Keywords: Polychlorinated biphenyl

Temporal trends of industrial organic contaminants can show how environmental burdens respond to changes in production, regulation, and other anthropogenic factors. Numerous studies have documented such from the Northern Hemisphere, while there is very limited data literature sub-Saharan Africa. We hypothesized that temporal legacy contemporary Africa could greatly differ regions which many these chemicals were initially produced more extensively used. For this purpose, a dated sediment core covering six decades floodplain system urban Dar es Salaam, Tanzania, was analysed. The samples analysed for selected persistent pollutants (POPs) [polychlorinated biphenyls (PCBs) polybrominated biphenyl ethers (PBDEs)] emerging concern (CECs) [alternative brominated flame retardants (aBFRs), chlorinated paraffins (CPs), dechloranes]. All groups showed steep increase concentrations towards uppermost layers reflecting recent years. Concentrations individual compound surface found order CPs >> aBFRs ∼ ∑ 25 PBDEs > dechloranes 32 PCBs. Time compounds differed, with PCBs showing presence sediments since at least early 1960s, some CECs first occurred corresponding last decade. Investigations into potential drivers observed socioeconomic factors related growth population, economy, waste generation contributed increasing PBDEs, aBFRs, CPs, Dechlorane Plus. Further monitoring areas Global South recommended.