The Hudson River, NY, USA is contaminated for over 300 km with polychlorinated biphenyls (PCBs) released from two General Electric (GE) capacitor plants. We collected adult and juvenile mallards (Anas platyrhynchos) from four different areas of the river; an area upstream of the GE plants (n = 38), two areas directly downstream of the GE plants (n = 41, n = 38), and an area more than 100 km downstream in the freshwater tidal river (n = 20). Collections occurred during July and August (2008) when ducks were flightless to ensure ducks were “resident” and exposures were local. Fat and muscle tissue were analyzed for PCBs. PCBs were detected in all samples, and mallards below the GE plant sites on the Hudson River had orders of magnitude higher concentrations of PCBs than those above the plants. Juvenile mallards from areas directly downstream of the GE plant sites tended to have higher PCB concentrations in fat than adults. The patterns of PCB congeners and homolog groups varied across the study areas, with areas directly downstream of the GE plants dominated by tetra-chloro biphenyls whereas samples from upstream and the freshwater tidal river tended towards higher chlorinated congeners. Congener patterns between male and female and juvenile and adult mallards were generally similar within study areas, with the exception of one area downstream of the GE plants where adult birds exhibited different patterns than juveniles. Evidence of PCBs from the GE plant sites was detected in the tidal Hudson River, more than 100 km downstream of the plant sites. More than 90% of the ducks collected in areas downstream of the GE plants but above the tidally influenced river exceed the USFDA tolerance level for PCBs in poultry, which should be a concern for consumers of waterfowl taken in proximity to the upper Hudson River.

PCBs (as Aroclor concentrations) have been extensively examined in fish along the Hudson River, but other xenobiotic chemicals in fish have had limited assessment. This study determined concentrations and congener distributions of polybrominated diphenyl ethers (PBDEs), polybrominated and polychlorinated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs and PCDD/Fs), and polychlorinated biphenyls (PCBs) in smallmouth bass and striped bass taken from a 385km reach of the Hudson River. Concentrations of PBDEs and PCBs in smallmouth bass, and PCBs in striped bass, were positively related to human uses of the compounds in the basin. Generally low levels of PCDD/Fs were found. One striped bass, however, contained elevated 2,3,7,8-TCDD, indicating exposure to a known source in the adjacent Newark Bay-Passaic River basin. PBDDs were generally below detection. PBDFs were present in four of 18 smallmouth bass, but were not detected in striped bass. Dioxin-like PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples.

Polychlorinated biphenyls (PCBs) were measured in the air and water over the Hudson River Estuary during six intensive field campaigns from December 1999 to April 2001. Over-water gas-phase PCB concentrations averaged 1100 pg/m3 and varied with temperature. Dissolved-phase PCB concentrations averaged 1100 pg/L and displayed no seasonal trend. Uncertainty analysis of the results suggests that PCBs with 5 or fewer chlorines exhibited net volatilization. The direction of net air/water exchange could not be determined for PCBs with 6 or more chlorines. Instantaneous net fluxes of PCBs ranged from +0.2 to +630 ng m-2 d-1. Annual fluxes of [summation operator]PCBs were predicted from modeled gas-phase concentrations, measured dissolved-phase concentrations, daily surface water temperatures and wind speeds. The net volatilization flux was +62 μg m-2 yr-1, corresponding to an annual loss of +28 kg/yr of PCBs from the Hudson River Estuary for the year of 2000. Investigation of the air-water exchange of PCBs in the Hudson River Estuary suggests that PCBs with 5 or fewer chlorines undergo net volatilization.

The use of “chemical fingerprinting” or “profiling” has been suggested as a means to identify habitat use by young-of-the-year (YOY) bluefish (Pomatomus saltatrix). In this study, seasonal and interannual trends were examined over a 3-year period of 31 polychlorinated biphenyl (PCB) congeners and 23 chlorinated pesticides in 176 YOY bluefish collected in the Hudson River Estuary, New York State. Principal component analysis identified distinct and coherent clustering of bluefish according to sampling year. Seasonally, PCB patterns were similar among weight classes, regardless of date of capture. Throughout the study period, there was a consistent seasonal shift toward the heavier chlorinated homologs as size increased even though different congeners contributed to the overall PCB profile in Year 3. Unlike PCBs, there was no consistent pesticide accumulation pattern, which varied seasonally and interannually. The results show the first generalized interannual accumulation profiles of organochlorines during the rapid growth stage of age-0 bluefish. As knowledge of temporal changes in different ecosystems improves, this will improve an understanding on how exposure to chemicals in different ecosystems can affect the long-term health of bluefish.

Aquatic environments are sinks for anthropogenic contamination, whether chemical or solid pollutants. Microfibers shed from clothing and other textiles contribute to this problem. These can be plastic or non-plastic origin. Our aim was to investigate the presence and distribution of both types of anthropogenic microfibers along the length of the Hudson River, USA. Surface grab samples were collected and filtered through a 0.45μm filter paper. Abundance of fibers was determined after subtraction of potential contamination. 233 microfibers were recorded in 142 samples, averaging 0.98microfibersL−1. Subsequent micro-FTIR showed half of the fibers were plastic while the other half were non-plastic, but of anthropogenic origin. There was no relationship between fiber abundance, wastewater treatment plant location or population density. Extrapolating from this data, and using available hydrographic data, 34.4% of the Hudson River's watershed drainage area contributes an average 300 million anthropogenic microfibers into the Atlantic Ocean per day.

Microplastics are a major environmental issue of concern. Since 2016, Hudson River Park has collaborated with Brooklyn College to survey microplastics within Park waters between Chambers and 59th Streets in Manhattan. It was hypothesized that microplastic concentration is influenced by proximity to combined sewer overflow (CSO) points, precipitation, and tides. Samples were collected at channel and near-shore locations at downtown and midtown sites. Microplastics were analyzed following NOAA methods via stereo microscope. Concentrations in 2018 were higher than in 2016, 2017 and 2019 ((ANOVA F (1,70) = 5.2, p < 0.03*; post hoc Tukey test p < 0.009*)), and near-shore sites tended to exhibit higher concentrations than channel sites (ANOVA and post-hoc Tukey: p < 0.03*). Microfibers were not fully accounted for and fragments were highly prevalent in all samples (~70%). Additional data will improve the understanding of the presence of microplastics in the Lower Hudson and elucidate the effects of wet weather on plastic concentrations.

Synthetic musks are used in many consumer products for their pleasant odor and their binding affinity for fabrics. In the early 1990s, polycyclic musks were reported to occur in air, water, sediment, wildlife, and humans from many European countries. Concentrations of polycyclic musks, particularly 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-[γ]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene (AHTN), have been reported to increase over time in the environment. In this study, concentrations of musks in water, sediment, fish, and mussel were determined from three locations along the upper Hudson River. HHCB and AHTN were detected in water (n = 5; 3.95-25.8 and 5.09-22.8 ng/L, respectively), sediment (n = 3; 72.8-388 and 113-544 ng/g, dry weight), fish (n = 30; <1-125 and <1-32.8 ng/g, lipid weight), and zebra mussel (n = 4; 10.3-19.3 and 42.2-65.9 ng/g, lipid weight) samples. Bioaccumulation factors of HHCB calculated for white perch, catfish, smallmouth bass, and largemouth bass were in the range of 18 to 371, when the concentrations in fish were expressed on a wet weight basis; the factors were in the range of 261 to 12,900, when the concentrations in fish were expressed on a lipid weight basis.