Microplastic abundance in gull nests in relation to urbanization.

Human activity and urbanization are having profound effects on natural landscapes and ecosystems. The presence and persistence of human-made materials such as microplastics can have major impacts on the health of organisms in both marine and terrestrial environments. We quantified microplastics in herring gull (Larus argentatus) and great black-backed gull (Larus marinus) nests at three colonies in the northeast United States that varied in their degree of urbanization: Jamaica Bay (JB) in New York City, Youngs Island (YI) on Long Island, New York, and Tuckernuck Island (TN) in Massachusetts. Nests in urban colonies contained a higher proportion of microplastics than those in the more remote colony. Our results link urbanization with microplastic accumulation in coastal environments and suggest that assessing microplastics in seabird nests could provide a means of evaluating microplastics encountered by seabirds and other coastal marine animals.

Determination of steroid estrogens in wastewater by immunoaffinity extraction coupled with HPLC-electrospray-MS.

A new method, based on immunoaffinity extraction coupled with liquid chromatography/electrospray mass spectrometry (LC/ESI-MS) is described for the determination of the steroid estrogens beta-estradiol (E2), estrone (E1), and alpha-ethynylestradiol (E2) in wastewater. The use of highly selective immunosorbents in sample preparation prior to analysis allows the removal of interfering sample matrix compounds present in the wastewater extracts that would otherwise cause severe ionization suppression of the estrogens during the electrospray process. In addition, immunoextraction removes much of the isobaric noise from the selected ion monitoring chromatograms, increasing the signal-to-noise ratios for analytes, and contributing to the low detection limits (0.18 and 0.07 ng/L for E2 and E1, respectively) achieved by the current method. The method was applied to analysis of estrogens in two wastewater effluents. Recoveries of E2 and E1 were excellent (>90%), while the nonimmunogen (but structurally related) analyte EE2 was not retained (recovery <2%) from effluent extracts by the immunosorbent. This illustrates the extreme selectivity of the immunoextraction purification step. Precision of the method was high, with relative standard deviations below 5%. Concentrations of E2 in wastewater varied from 0.77 to 6.4 ng/L, while concentrations of E1 were greater (1.6-18 ng/L).

Distribution and fate of neutral alkylphenol ethoxylate metabolites in a sewage-impacted urban estuary.

The distribution and fate of neutral metabolites of the alkylphenol ethoxylate (APEO) surfactants in an urbanized estuarine environment were examined utilizing a recently developed, highly sensitive LC-MS method. Results indicated that short ethoxyl-chain APEOs and alkylphenols (APs) were present in surficial sediments throughout the estuary at concentrations roughly correlated to the organic carbon content of the sediment and that the APEO mixture was dominated by nonylphenol ethoxylate (NPEOs) metabolites (0.05-30 microg/g), with lesser amounts of octylphenol ethoxylate metabolites (OPEOs)(<0.005-0.09 microg/ g) and halogenated nonylphenols (<0.001-0.03 microg/g). NPEO metabolites in surface water (0.22-1.05 microg/L) were also present at higher concentrations than OPEO metabolites (0.007-0.040 microg/L). APEO metabolite concentrations in both sediment and water showed a strong correlation with conventional sewage tracers, affirming a wastewater source of these contaminants. APEO distributions in surface waters within the estuary could be explained by a combination of post-discharge degradation and mixing with a seawater end-member enriched in OPEO metabolites. Measured in situ Koc values of APEO metabolites were comparable to previously reported values derived from field experiments but higher than Kow and Koc values derived from laboratory experiments. Results from the present work indicate that the fate of APEO metabolites entering the estuarine environment through discharge of wastewater is directed primarily by scavenging onto particles and subsequent burial in sediments, degradation during residence in the water column, and transport out of the estuary through advective and dispersive processes.

Analysis of alkylphenol ethoxylate metabolites in the aquatic environment using liquid chromatography-electrospray mass spectrometry.

A quantitative method is described for the analysis of the metabolites of alkylphenol ethoxylate (APEO) surfactants in estuarine water and sediment samples using reversed-phase high-performance liquid chromatography with electrospray mass spectrometry detection. Nonyl- and octylphenols, nonyl- and octylphenol mono-, di-, and triethoxylates, halogenated nonylphenols, and nonylphenol ethoxycarboxylates were concentrated from water samples using a C18 solid-phase extraction procedure. A novel, continuous-flow, high-temperature, sonicated extraction system was developed to isolate APEO metabolites from sediment samples. Quantitative LC-MS was performed in the negative ion mode for nonylphenols, octylphenols, and halogenated nonylphenols and in the positive ion mode for nonyl- and octylphenol ethoxylates using selected ion monitoring with isotopically labeled surrogate standards. Recoveries for sediment and water analyses ranged between 78 and 94%, and detection limits for APEO metabolites were between 1 and 20 pg injected on column. This is a significant improvement over previously reported methods. Suppression of analyte response was encountered in the presence of matrix components in sediment samples, but this effect was eliminated by careful selection of surrogate and internal standards. Individual APEO metabolite concentrations of 1-320 ng/L and 5-2000 ng/g are reported for water and sediment samples, respectively, from Jamaica Bay, NY.