Occurrence and Distribution of Per- and Polyfluoroalkyl Substances from Multi-Industry Sources to Water, Sediments and Plants along Nairobi River Basin, Kenya

Flora Chirikona; Natalia Quinete; Jesleen Gonzalez; Gershom Mutua; Selly Kimosop; Francis Orata

doi:10.3390/ijerph19158980

Occurrence and Distribution of Per- and Polyfluoroalkyl Substances from Multi-Industry Sources to Water, Sediments and Plants along Nairobi River Basin, Kenya

Int J Environ Res Public Health. 2022 Jul 23;19(15):8980. doi: 10.3390/ijerph19158980.

Authors

Flora Chirikona¹, Natalia Quinete², Jesleen Gonzalez², Gershom Mutua¹, Selly Kimosop¹, Francis Orata¹

Affiliations

¹ Department of Pure and Applied Chemistry, School of Natural Sciences, Masinde Muliro University of Science and Technology, P.O. Box 190, Kakamega 50100, Kenya.
² Department of Chemistry & Biochemistry, Freshwater Resources Division, Institute of Environment, Biscayne Bay Campus North Miami, Florida International University, 3000 NE 151st Street, North Miami, FL 33181, USA.

Abstract

Per- and polyfluoroalkyl substances (PFAS) are ever-present pollutants in the environment. They are persistent and bio-accumulative with deleterious health effects on biota. This study assesses the levels of PFAS in environmental matrices along the Nairobi River, Kenya. An aggregate of 30 PFAS were determined in water, while 28 PFAS were detected in sediments and plants using solid phase extraction then liquid chromatography-mass spectrometric techniques. In water, higher levels of perfluoroundecanoic acids of up to 39.2 ng L^-1 were observed. Sediment and plant samples obtained in the midstream and downstream contained higher levels of perfluorooctanoic acid of up to 39.62 and 29.33 ng g^-1, respectively. Comparably, levels of long-chain PFAS were higher in water and sediments than in plants. Sediment/water log distribution of selected PFAS ranged between 2.5 (perfluoroundecanoic acid) and 4.9 (perfluorooctane sulfonate). The level of perfluorooctane sulfonate (1.83 ng L^-1) in water is above the acceptable level in surface water posing high human health and ecological risks. The observed PFAS concentrations and distribution were attributed mainly to multi-industries located along the river, among other sources. The knowledge of PFAS occurrence and distribution in Nairobi River, Kenya, provides important information to local regulatory agencies for PFAS pollution control.

Keywords: Amaranthus viridis; Nairobi River; PFAS; distribution coefficient; sediments; surface water.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Alkanesulfonic Acids* / analysis
Environmental Monitoring
Fluorocarbons* / analysis
Humans
Kenya
Water / analysis
Water Pollutants, Chemical* / analysis

Substances

Alkanesulfonic Acids
Fluorocarbons
Water Pollutants, Chemical
Water

Grants and funding

This research was co-funded by International Foundation for Science (IFS) and Organization for Prohibition of Chemical Weapons (OPCW) grant Name 12-W-6512-1.