Out of sight but not out of mind: harmful effects of derelict traps in selected U.S. coastal waters.

There is a paucity of data in the published literature on the ecological and economic impacts of derelict fishing traps (DFTs) in coastal ecosystems. We synthesized results from seven NOAA-funded trap fisheries studies around the United States and determined that DFT-caused losses to habitat and harvestable annual catch are pervasive, persistent, and largely preventable. Based on this synthesis, we identified key gaps to fill in order to better manage and prevent DFTs. We conclude with suggestions for developing a U.S. DFT management strategy including: (1) targeting studies to estimate mortality of fishery stocks, (2) assessing the economic impacts of DFTs on fisheries, (3) collaborating with the fishing industry to develop solutions to ghost fishing, and (4) examining the regional context and challenges resulting in DFTs to find effective policy solutions to manage, reduce, and prevent gear loss.

Determination and comparison of nitrated-polycyclic aromatic hydrocarbons measured in air and diesel particulate reference materials.

The National Institute of Standards and Technology has issued numerous environmental matrix standard reference materials (SRMs) for the measurement of polycyclic aromatic hydrocarbons; however, only one SRM (diesel particulate material) was issued with certified and reference values for four nitrated-polycyclic aromatic hydrocarbons (nitro-PAH). The objective of this study was to develop an improved analytical procedure to quantify 28 mononitro- and dinitro-PAHs, including numerous isomers, in air and diesel particulate SRMs. Two air particulate matrix SRMs, SRM 1649a Urban Dust and SRM 1648 Urban Particulate Matter, and fine particulate matter, collected from Baltimore MD for use as an "interim reference material" for the determination of organic contaminants, have been characterized for nitro-PAHs. Concentrations of nitro-PAHs in all three air particulate materials were at the ng/g level with the highest nitro-PAH concentration being 2-nitrofluoranthene (range between 246 and 340 ng/g). For the three diesel particulate-related SRMs, SRM 1650a Diesel Particulate Matter, SRM 1975 Diesel Particulate Extract, and SRM 2975 Diesel Particulate Matter (Industrial Fortlift), concentrations of nitro-PAHs were in the microg/g range, with 1-nitropyrene as the dominant nitro-PAH (range between 18 and 40 microg/g). Distinct nitro-PAH isomer patterns were present between the air and diesel particulate materials. These results will provide isomer identification and reference concentrations for a large number of nitro-PAHs in the existing diesel and air particulate SRMs. Published by Elsevier Science Ltd.

Determination of nitrated polycyclic aromatic hydrocarbons in diesel particulate-related standard reference materials by using gas chromatography/mass spectrometry with negative ion chemical ionization.

Gas chromatography/mass spectrometry (GC/MS) with negative ion chemical ionization (NICI) detection was utilized for quantitative determination of nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) in diesel particulate-related standard reference materials (SRMs). Prior to GC/MS analysis, isolation of the nitro-PAHs from the complex diesel particulate extract was accomplished using solid phase extraction (SPE) and normal-phase liquid chromatographic (LC) fractionation using an amino/cyano stationary phase. Concentrations of eight to ten mononitro-PAHs and three dinitropyrenes were determined in three diesel particulate-related SRMs: SRM 1650a Diesel Particulate Matter, SRM 1975 Diesel Particulate Extract, and SRM 2975 Diesel Particulate Matter (Industrial Forklift). The results from GC/MS NICI using two different columns (5% phenyl methylpolysiloxane and 50% phenyl methylpolysiloxane) were compared to each other and to results from two other laboratories for selected nitro-PAHs. 1-Nitropyrene was the most abundant nitro-PAHs in each of the diesel particulate SRMs (19.8+/-1.1 micro g g(-1) particle in SRM 1650a and 33.1+/-0.6 micro g g(-1) particle in SRM 2975). Three dinitropyrene isomers were measured in SRM 1975 at 0.5-1.4 micro g g(-1) extract and in SRM 2975 at 1-3 micro g g(-1) particle.

Atmospheric concentrations and fluxes of organic compounds in the northern San Francisco Estuary.

A study was conducted to measure atmospheric concentrations of PAHs and PCBs and estimate their fluxes between air and water in the northern San Francisco Estuary. Ambient air samples were collected once every 12 days at a single sampling site in Concord, CA, from June to November 2000, using a modified high-volume air-sampling device equipped with glass fiber filters and polyurethane foam. Concentrations of total PAHs and PCBs ranged from 5.7 to 56 and 0.17 to 0.32 ng/m3, respectively. PAHs and PCBs in the ambient air were predominantly in the vapor phase (83-99%). Gaseous fluxes of PAHs in the estuary showed high seasonal variation, ranging from 110 ng x m(-2) x day(-1) efflux in August to 1,050 ng x m(-2) x day(-1) influx in November. Gaseous PCBs showed consistent net volatilization 12.2-24 ng x m(-1) x day(-1)) for this period. Particle settling contributed estimated net deposition fluxes of 45-960 ng x m(-2) day(-1) for PAHs and 0.39-2.1 ng x m(m(-2) x day(-1) for PCBs. Combining these fluxes, PAHs were either deposited to or lost from the estuary via the atmosphere, depending on the month. In contrast, there consistently was net emission of PCBs from the estuary to the atmosphere.

Seasonal and annual air-water exchange of polychlorinated biphenyls across Baltimore Harbor and the northern Chesapeake Bay.

As part of the Atmospheric Exchange Over Lakes and Oceans Study (AEOLOS), air-water exchange fluxes of polychlorinated biphenyls (PCBs) were determined along a transect in the Baltimore Harbor from the Inner Harbor of Baltimore, MD, to the mainstem of the northern Chesapeake Bay to assess the overall contributions of urban source PCBs through air-water exchange and their impacts on coastal waters. Six sites were sampled during three intensive sampling periods in June 1996, February 1997, and July 1997 and at two sites (urban and rural) every ninth day between March 1997 and March 1998 to measure spatial and temporal variability in the PCB air-water exchange fluxes. During the intensive sampling campaigns, net total PCB (t-PCBs) volatilization fluxes ranged between 5 and 2120 ng m(-2) day(-1), varying on both temporal and spatial scales. Volatilization fluxes were highest in February, driven by high winds and elevated dissolved PCB concentrations. Throughout the annual sampling period, t-PCB volatilization fluxes were similar between urban (130 microg m(-2) yr(-1)) and rural (120 microg m(-2) yr(-1)) sites. Approximately 10% of the dissolved t-PCB inventory in the water column in Baltimore Harbor exchanges with the atmosphere each day. From air-water exchange alone, the estimated residence time of dissolved t-PCBs in the harbor is approximately 10 days (estimated hydraulic residence time of water in the harbor is between 7 and 14 days), indicating that air-water exchange is an efficient removal mechanism of t-PCBs from urban coastal waters. Furthermore, the annual flux of t-PCBs volatilizing from Baltimore Harbor is approximately 12% of the gas-phase t-PCB inventory over the water, and at the northern Chesapeake Bay site, the t-PCB flux is approximately 40% of the gas-phase t-PCB inventory. This suggests that air-water exchange of t-PCBs has the potential to be a significant source of PCBs to the rural atmosphere.

Using extrathermodynamic relationships to model the temperature dependence of Henry's law constants of 209 PCB congeners.

Our previous measurements of the temperature dependencies of Henry's law constants of 26 polychlorinated biphenyls (PCBs) showed a well-defined linear relationship between the enthalpy and the entropy of phase change. Within a homologue group, the Henry's law constants converged to a common value at a specific isoequilibrium temperature. We use this relationship to model the temperature dependencies of the Henry's law constants of the remaining PCB congeners. By using experimentally measured Henry's law constants at 11 degrees C for 61 PCB congeners described in this paper combined with the isoequilibrium temperatures from our previous measurements of Henry's law constants of 26 PCB congeners, we have derived an empirical relationship between the enthalpies and the entropies of phase change for these additional PCB congeners. A systematic variation in the enthalpies and entropies of phase change was found to be partially dependent on the chlorine number and substitution patterns on the biphenyl rings, allowing further estimation of the temperature dependence of Henry's law constants for the remaining 122 PCB congeners. The enthalpies of phase change for all 209 PCB congeners ranged between 10 and 169 kJ mol(-1), where the enthalpies of phase change decreased as the number of ortho chlorine substitutions on the biphenyl rings increased within homologue groups. These data are used to predict the temperature dependence of Henry's law constants for all 209 PCB congeners.