Intraday and interday variations of 69 volatile organic compounds (BVOCs and AVOCs) and their source profiles at a semi-urban site

Serpil Yenisoy-Karakaş; Melike Dörter; Mustafa Odabasi

doi:10.1016/j.scitotenv.2020.138028

Intraday and interday variations of 69 volatile organic compounds (BVOCs and AVOCs) and their source profiles at a semi-urban site

Sci Total Environ. 2020 Jun 25:723:138028. doi: 10.1016/j.scitotenv.2020.138028. Epub 2020 Mar 19.

Authors

Serpil Yenisoy-Karakaş¹, Melike Dörter², Mustafa Odabasi³

Affiliations

¹ Department of Chemistry, Bolu Abant Izzet Baysal University, 14030 Bolu, Turkey. Electronic address: yenisoykarakas_s@ibu.edu.tr.
² Department of Chemistry, Bolu Abant Izzet Baysal University, 14030 Bolu, Turkey.
³ Department of Environmental Engineering, Dokuz Eylül University, Izmir, Turkey.

PMID: 32229382
DOI: 10.1016/j.scitotenv.2020.138028

Abstract

To study the intraday and interday patterns and possible sources of volatile organic compounds (VOCs), 6-h active sampling was performed in April, May, June, July, and August 2017 and in January 2018 in a semi-urban site in Bolu, Turkey. Totally 69 VOCs having biogenic (BVOCs, i.e., isoprene, monoterpenes and oxygenated VOCs) and anthropogenic origins (AVOCs) were examined. Fifty-four of sixty-nine analyzed VOCs could be detected. Decanal followed by benzaldehyde, benzene, phenol, and toluene were detected as the leading anthropogenic VOCs whereas alpha-pinene and hexanal were the dominant biogenic VOCs. There was a decrease in concentrations of most of the VOCs in January and April when light intensity and temperature were relatively low. Atmospheric levels of total biogenic VOCs exceeded that of anthropogenic VOCs in all months except for January and April. Dependence of biogenic VOC emissions on the light intensity, temperature and the increase in leaves were considered to be effective in their higher levels in summer and daytime periods. The daytime anthropogenic VOCs concentrations were higher than the nighttime anthropogenic VOCs probably due to intense vehicle traffic during working hours and/or increased volatilization from their sources at elevated temperatures. The VOCs that significantly and negatively correlated with ozone were evaluated as effective BVOCs in the ozone formation while the maximum incremental reactivity (MIR) method gave the contribution of AVOCs. Positive Matrix Factorization (PMF) was applied for the source apportionment. G score graphs and G score pollution roses were also used to identify possible sources of investigated VOCs. Solvent evaporation, gasoline-powered vehicle emissions, fossil fuel (residential heating), biogenic (hornbeam, grass, oak, beech) emissions, diesel/domestic activities and forested city atmosphere were identified as the possible VOC sources in the study area.

Keywords: 6-hourly variations; Anthropogenic VOCs; Biogenic VOCs; Positive matrix factorization; Source apportionment.