Atmospheric Seasonal Trends and Environmental Fate of Alkylphenols in the Lower Hudson River Estuary

Abstract

The atmospheric occurrence of nonylphenols and tert-octylphenol has been assessed at three sites in the lower Hudson River Estuary (LHRE). The samples (n = 186) were taken from June to December of 1998. Gas-phase nonylphenol (NP) concentrations at a coastal site (Sandy Hook) ranged from below the detection limit (DL) to 56.3 ng m-3, while concentrations at a suburban site (New Brunswick) ranged from 0.13 to 81 ng m-3. Gas-phase concentrations of tert-octylphenol (tOP) ranged from <DL to 1.0 ng m-3 at Sandy Hook and from 0.01 to 2.5 ng m-3 at New Brunswick. NPs and tOP exhibited seasonal dependence with higher gas-phase concentrations during summer than during fall and early winter. Temperature explained 40−62% of the variability in the log (gas phase) NP and tOP concentrations. Assessment of the influence of local wind direction on atmospheric NP concentrations provided evidence for the predominance of local sources rather than long-range transport. Based on simultaneous water and over-water gas-phase samples and subsequent estimation of air−water exchange fluxes, volatilization and advection to the Atlantic Ocean accounted for 40 and 26% of the removal of NPs from the water column of the LHRE, respectively. The estimated half-life of NPs in the water column of the LHRE was 9 days.