Perfluorinated Compounds Distribution and Source Identification in Sediments of Lake Victoria Gulf Basin

Abstract

IWW Rheinisch-westfälisches Institut für Wasser, Mülheim an der Ruhr, GermanyPerfluorooctanoic acid and perfluorooctane sulfonate were determined in the sediments from Winam Gulf, which is in the Kenyan side of Lake Victoria and in its source rivers. The sources of perfluorinated compounds within the Gulf of Lake Victoria have been identified and their levels determined for the first time, in this study, using SPE and HPLC-MS-MS analytical methodology. Variability in the concentrations of perfluorooctanoic acid and perfluorooctane sulfonate ranged from 1.4-99.1 and <1-57.5 ng/g in river sediments, respectively, which was higher than concentrations obtained from lake sediments (range perfluorooctanoic acid <1-24.1 ng/g and perfluorooctane sulfonate <1-4.0 ng/g). The results obtained suggested generalized point sources such as domestic and industrial waste indicated by significant correlation and regression of r 2 = 0.857. Sampling sites within and near sewage and water treatment facilities gave the highest concentrations of both analytes, and were observed to be the main source of perfluorinated compounds pollution. The lowest limit of quantification was 1 ng/g for both analytes and limits of detection were 0.1 and 0.2 ng/g for perfluorooctanoic acid and perfluorooctane sulfonate, respectively. Typical values for recovery obtained were higher than 78% from spiked amounts ranging from 1 to 150 ng. Quantifying perfluoro alkylated compounds in sediments have provided insights into their source, distribution, and mobility in the Lake Victoria Basin.

Occurrences and toxicological risk assessment of eight heavy metals in agricultural soils from Kenya, Eastern Africa

“…In the Lake Victoria, high concentrations of heavy metals including Zn and Cd have been reported (Orata et al 2011). In the Kenyan coast, pollution of heavy metals has been reported from sediments in Makupa and Port-Reitz Creek systems, with high levels of Cu and Pb associated to municipal dumping and industrial activities in the area (Muohi et al 2003).…”

Risks posed by per‐ and polyfluoroalkyl substances (PFAS) on the African continent, emphasizing aquatic ecosystems

“…The PFOS concentrations in sediments from the Diep and Eerste rivers in South Africa (Mudumbi et al, 2014) and in several rivers in the Lake Victoria Basin in Kenya (Orata et al, 2011) exceeded the EQS values for sediment to protect pelagic species (Casado‐Martinez et al, 2021). The concentrations in sediments of the Diep and Eerste rivers also exceeded the threshold value set to protect benthic organisms (INERIS, 2018).…”

Distribution of perfluoroalkyl substances (PFASs) in water, sediment, and fish tissue, and the potential human health risks due to fish consumption in Lake Hawassa, Ethiopia

“…Most studies on PFASs in the environment are conducted in the Northern hemisphere including North America, Europe, and Asia (Furdui et al, 2007;Martin et al, 2003;Sinclair et al, 2006;Taniyasu et al, 2003), whereas less is done on the PFASs distribution in African aquatic ecosystems and the subsequent potential human exposure in these countries (Mudumbi et al, 2014;Orata et al, 2009;Ssebugere et al, 2020). In addition to that, most investigation of PFASs, in aquatic biota and the abiotic environment in Africa, have been done in South Africa (Fagbayigbo et al, 2018;Fauconier et al, 2019;Groffen et al, 2018;Mudumbi et al, 2014;Verhaert et al, 2017), Kenya (Orata et al, 2009;Orata et al, 2011), and Tanzania (Groffen et al, 2021a), whereas only one study has been done in Ethiopia (at Lake Tana) (Ahrens et al, 2016).…”