Halomethoxybenzenes (HMBs) are a group of compounds with natural and anthropogenic origins. Here weextend a 2002e2015 survey of bromoanisoles (BAs) in the air and precipitation at Rå€o on the Swedish westcoast and Pallas in Subarctic Finland. New BAs data are reported for 2018 and 2019 and chlorinated HMBsare included for these and some previous years: drosophilin
A methyl ether (DAME: 1,2,4,5-tetrachloro-3,6-dimethoxybenzene), tetrachloroveratrole (TeCV: 1,2,3,4-tetrachloro-5,6-dimethoxybenzene), and penta-chloroanisole (PeCA). The order of abundance of HMBs at Rå€o was SBAs > DAME > TeCV > PeCA, whereasat Pallas the order of abundance was DAME > SBAs > TeCA > PeCA. The lower abundance of BAs at Pallasreflects its inland location, away from direct marine influence.
Clausius-Clapeyron (CC) plots of log partialpressure (Pair)/Pa versus 1/T suggested distant transport at both sites for PeCA and local exchange for DAMEand TeCV. BAs were dominated by distant transport at Pallas and by both local and distant sources at Rå€o.Relationships between air and precipitation concentrations were examined by scavenging ratios, SR ¼ (ngm3)precip/(ng m3)air.
SRs were higher at Pallas than Rå€o due to greater Henry's law partitioning of gaseouscompounds into precipitation at colder temperatures. DAME is produced by terrestrial fungi. We screened19 fungal species from Swedish forests and found seven of them contained 0.01e3.8 mg DAME per kg freshweight.
We suggest that the volatilization of DAME from fungi and forest litter containing fungal myceliamay contribute to atmospheric levels at both sites.
2023. Vol. 13, p. 100209-100209, article id 100209