Occurrence and Distribution of Polybrominated Diphenyl Ethers in Water from Nairobi River Basin, Kenya, East Africa

Abstract

Polybrominated diphenyl ethers are linked to adverse health effects that includethyroid hormone disruption, neuro-developmental deficit, abnormal pregnancy,and potential carcinogens. This study was aimed at assessing the concentrationsof selected Polybrominated diphenyl ether compounds in water of Nairobi River.Water samples were collected by grab method from nine sites along the river andanalysed for brominated diphenyl ethers using gas chromatography coupled withmass spectrometer. The mean concentration of polybrominated diphenyl ethersresidue in water ranged from <0.0009 to 72.89 ± 6.15 ng/L. The dominantcongeners were 2,2′,4,4′-tetra- bromodiphenyl ether, 2,2′,4,4′,5,5′-hexabromodiphenylether, 2,2′,4,4′,6-penta-bromodiphenyl ether, 2,2′,4,4′,5,5′-hexabromodiphenylether and 2,2′,4,4′,5,6′-hexa-bromodiphenyl. The highest meanconcentration of 2,2′,4,4′-tetra- bromodiphenyl ether was 72.89 ± 6.15 ng/L,2,2′,3,4,4′-penta- bromodiphenyl ether was 14.08±0.68 ng/L, 2,2′,4,4′,6-pentabromodiphenylether was 43.67±1.47 ng/L, 2,2′,4,4′,5,5′-hexa-bromodiphenylether was 24.78±2.49 ng/L, and 2,2′,3,4,4′,5′,6-hepta-bromodiphenyl ether was11.75±0.97 ng/L. Consequently, as these compounds are known to bioaccumulatein fatty tissues, continued use of the river water poses a health risk toanimals and humans due to contamination across the food chain.