Persistence of nonylphenol ethoxylate surfactants and their primary degradation products in sediments from near a municipal outfall in the strait of Georgia, British Columbia, Canada

Marine sediment cores and surface grabs were collected from the Strait of G eorgia, British Columbia, Canada, near the lona municipal outfall and were analyzed for nonylphenol (NP) and its ethoxylate compounds (NPnEOs). We use d normal-phase liquid chromatography with electrospray mass spectrometric d etection to determine concentrations of ethoxylates from n = 1 to n = 19. O ver half the NPnEO inventory in marine sediments resides in ethoxylates of chain length greater than n = 2, suggesting that analyses limited to short- chain ethoxylates (n = 2) are under-reporting total NPnEO by a factor of 2. The NPnEO vertical profiles and oligomer distributions in dated sediment c ores suggest that little degradation occurs once these compounds enter the sediments: the half-life for these compounds is estimated to be greater tha n 60 yr. The lack of change in NPnEO oligomer distribution with age suggest s that degradation by chain shortening does not occur significantly. A roug h inventory shows that over 30 t of NPnEO resides in Fraser River Delta sed iments near the lona municipal outfall and that the entire Strait of Georgi a sediments contain over 170 t of NPnEO.