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Gunnar G. Lauenstein 《Marine pollution bulletin》1995,30(12):826-833
Organic contaminant concentrations in mussels and oysters were compared between archived samples of a Mussel Watch Program of the 1970s and samples collected more recently by the National Oceanic and Atmospheric Admnistration's National Status and Trends Program. Archived samples were analysed using current analytical techniques. Chlorinated pesticides and PAHs (polyaromatic hydrocarbons) displayed significant decreases between the 1970s and the 1990s. Polychlorinated biphenyls (PCBs) and butyltins were found in higher concentrations in 1986 than in the 1970s samples. Concentrations for both have decreased since 1986. The original 1970s analytical results were also compared with current analytical results from archived samples. Results were comparable for DDE and were generally comparable for the greater than three-ring PAHs. Results were also comparable for PCBs, even though the early methods quantified Arochlor 1254 and the more recent method quantifies PCBs by congener. 相似文献
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Abstract: Landslide research at the British Geological Survey (BGS) is carried out through a number of activities, including surveying, database development and real-time monitoring of landslides. Landslide mapping across the UK has been carried out since BGS started geological mapping in 1835. Today, BGS geologists use a combination of remote sensing and ground-based investigations to survey landslides. The development of waterproof tablet computers (BGS·SIGMAmobile), with inbuilt GPS and GIS for field data capture provides an accurate and rapid mapping methodology for field surveys. Regional and national mapping of landslides is carried out in conjunction with site-specific monitoring, using terrestrial LiDAR and differential GPS technologies, which BGS has successfully developed for this application. In addition to surface monitoring, BGS is currently developing geophysical ground-imaging systems for landslide monitoring, which provide real-time information on subsurface changes prior to failure events. BGS’s mapping and monitoring activities directly feed into the BGS National Landslide Database, the most extensive source of information on landslides in Great Britain. It currently holds over 14?000 records of landslide events. By combining BGS’s corporate datasets with expert knowledge, BGS has developed a landslide hazard assessment tool, GeoSure, which provides information on the relative landslide hazard susceptibility at national scale. 相似文献
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Cadmium (Cd) concentrations in the coastal United States were assessed using the National Status and Trends (NS&T) Mussel Watch dataset, which is based on the analysis of sediments and bivalves collected from 280 sites since 1986. Using the 1997 sediment data, Pearson correlation (r = 0.44, p < 0.0001) suggested that Cd distributions in sediment can, be to some extent, explained by the proximity of sites to population centers. The 2003 tissue data indicated that “high” Cd concentrations (greater than 5.6 μg/g dry weights [dw] for mussel and 5.4 μg/g dw for oysters) were related to salinity along the East and Gulf coasts. Along the West coast, however, these “high” sites appeared to be related to upwelling phenomenon. Additionally, sedimentary diagenesis was found to be the most likely explanation of why sediment and mollusk Cd content were not well correlated. 相似文献
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The September 11, 2001 attack on the World Trade Center (WTC) resulted in a massive plume of dust and smoke that blanketed lower Manhattan and part of the Hudson-Raritan Estuary (HRE). The NOAA National Status and Trends Mussel Watch Program has long-term monitoring sites in the area and thus had an opportunity to assess the effect of the WTC attack on PAH and PCB contamination of the surrounding estuary. Seven additional sites were added in the Upper HRE to attain higher sampling resolution for comparison with regularly sampled Mussel Watch Project HRE sites. Elevated background levels of PCBs and PAHs in mussel tissue and sediments were high enough before the WTC attack that concentrations were not measurably changed by WTC derived contaminant input. 相似文献
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The attack on the World Trade Center (WTC) resulted in the destruction of buildings, and the release of tons of dust and debris into the environment. As part of the effort to characterize the environmental impact of the WTC collapse, Mussel Watch Program trace element measurements from the Hudson–Raritan Estuary (HRE) were assessed for the years before (1986–2001) and after (2001–2005) the attack. Trace element measurements in the HRE were significantly higher than Mussel Watch measurements taken elsewhere in the Nation. Post-attack trace element measurements were not significantly different from pre-attack measurements. The impacts of WTC collapse may have been obscured by high ambient levels of trace elements in the HRE. 相似文献
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Coastal contamination in the 1940s was assessed based on analysis of canned blue mussels presumably collected from Birch Harbor, Maine, USA. Analytical results on legacy organic contaminants were compared to long-term National Oceanic and Atmospheric Administration (NOAA) Mussel Watch (MW) monitoring data to estimate the degree of coastal contamination before World War II (WWII) when many synthetic organic compounds were first introduced into the environment. While dieldrin and chlordane were not detected in the canned mussels, dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexanes (HCHs) were present at lower concentrations relative to the more recent MW data. Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were detected, and the later were significantly higher in canned mussels relative to the MW data (p < 0.05). Furthermore, moving average analysis applied to the MW data depicted three-phased temporal trend patterns (increase-decrease-steady state) for virtually all contaminants indicating an overall increased coastal contamination in post WWII era. 相似文献
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Trends in chemical concentrations in mussels and oysters collected along the US coast: update to 2003 总被引：2，自引：0，他引：2
With data from the annual analyses of mussels and oysters collected in 1986-1993 from sites located throughout the coastal United States [O'Connor, T.P., 1996. Trends in chemical concentrations in mussels and oysters collected along the US coast from 1986 to 1993. Mar. Environ. Res. 41, 183-200] showed decreasing trends, on a national scale, for chemicals whose use has been banned or has greatly decreased and that concentrations of most other chemicals were neither increasing nor decreasing. With data through 2003 those conclusions still apply. National median concentrations of synthetic organic chemicals and cadmium continue to decrease. The added data show that concentrations of lindane and high molecular weight PAHs are also decreasing on a national scale. For metals other than cadmium and zinc (in mussels), the added data reveal trends at more sites than in 1993 but no additional national trends. However, the longer time series has revealed several local and regional trends. 相似文献
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