Occurrence and Distribution of Polychlorinated Naphthalenes in Consumer Products and Landfill Matrices: A First Assessment in South Africa

Abstract

Polychlorinated Naphthalenes (PCNs) are persistence organic pollutants (POPs) which have been used extensively and continue to be a source of environmental and human health issues in spite of the international ban on their production. This work represents the first report of PCNs in consumer goods, landfill leachate, and sediment samples in South Africa. In this study, a total of 24 consumer goods belonging to eight categories were analyzed along with landfill leachates and sediments from the Hatherly and Goudkoppies landfills, Gauteng Province, South Africa, for some selected PCN congeners by gas chromatography mass spectrometry (GC-MS) analysis. Quality assurance procedures and principal component analysis (PCA) were employed to ensure analytical reliability and evaluate similarities among sample matrices and PCN homologue groups. Concentrations of the ΣPCN varied from 16.07-177.69 ng/g in consumer products, from 37.40-66.72 ng/L in landfill leachates and from 39.02-106.83 ng/g in sediments. Increased levels of PCN were found in some electrical and polymer-containing consumer products but no statistically significant relationship between chlorine contents and ΣPCN concentrations. PCA showed matrix-dependent variations in the distribution of congeners, suggesting different partitioning behaviour for consumer products, landfill leachates, and sediments. The detected concentrations indicate that consumer products may serve as important secondary sources of PCNs in landfill environments, contributing to their environmental persistence and potential ecological exposure. These findings provide important baseline information for determining the distribution and presence of PCNs in South Africa, which underscores the need for continuous environmental monitoring, better waste management practices, development of a national PCN inventory as well as risk assessments that will aid in the implementation of the Stockholm Convention.