Concentration and distribution of PCNs in ambient soil of a municipal solid waste incinerator

Highlight
• Impact of MSWI on PCNs in surrounding soil was studied.
• Analysis suggested that MSWI may be a direct source of PCNs in soils.
• Limited area surrounding MSWI was influenced by emissions.
• Decline of PCNs with increasing distance from the stack was quantified.

The impact of a typical municipal solid waste incinerator (MSWI) on polychlorinated naphthalene (PCN) concentrations in surrounding soil was studied. We collected 6 stack gas samples from the MSWI and 21 soil samples from sampling sites at distances of between 300 and 1700 m from the MSWI stack. Total dl-PCN (dioxin-like PCN) concentrations in the stack gas samples ranged from 6898 and 89,032 pg m− 3, with a mean value of 36,241 pg m− 3. The total dl-PCN concentrations in the soil samples ranged from 30.35 to 280.9 pg g− 1, with a mean value of 87.03 and a median value of 70.32 pg g− 1, while the TEQ values were between 7.7 and 130.2 fg TEQ g− 1, with a mean value of 41.12 fg TEQ g− 1 and a median value of 31.52 fg TEQ g− 1. The PCN homologue patterns and the results of Principal Component Analysis suggested that the MSWI may be a source of PCNs in the soils. A contour map, created using an ordinary Kriging interpolation technique, showed that a limited area (≤ 1000 m radius) surrounding the MSWI was influenced by the emissions from the MSWI. Furthermore, an exponential function equation was proposed to quantify the relationship between TEQs of PCNs and the distance from the stack.