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561.
Biomagnification factors (fish to Osprey eggs from Willamette River,Oregon, U.S.A.) for PCDDs,PCDFs, PCBs and OC pesticides 总被引:3,自引:0,他引:3
Henny CJ Kaiser JL Grove RA Bentley VR Elliott JE 《Environmental monitoring and assessment》2003,84(3):275-315
A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g-1 wet weight (ww), PCBs 0.69 g g-1, 2,3,7,8-TCDD 2.3 ng kg-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed. 相似文献
562.
Soils derived from dredged material were collected, together with earthworms from nine confined disposal facilities located in the Great Lakes Region. These samples were analyzed for 18 elements, 11 organochlorine pesticides, PCBs, and 24 polycyclic aromatic hydrocarbons. The concentrations detected in earthworms were evaluated in terms of their potential hazard to wildlife, which for the sake of the evaluation were assumed to prey entirely either on earthworms or on other soil invertebrates having similar concentrations. The soil concentrations (dry wt.) of the contaminants of greatest concern were <1.9 to 32 ppm Cd, <0.053 to 0.94 ppm Hg, 4.6 to 550 ppm Pb, and <0.1 to 1.0 ppm PCBs. The concentrations in earthworms (dry wt., ingested soil included) were as high as 91 ppm Cd, 1.6 ppm Hg, 200 ppm Pb, and 1.8 ppm PCBs. Based on laboratory toxicity studies of relatively sensitive species, and on concentration factors calculated from the earthworm and soil data, we estimated that lethal or serious sublethal effects on wildlife might be expected at concentrations of 10 ppm Cd, 3 ppm Hg, 670 ppm Pb, and 1.7 ppm PCBs in alkaline surface soils derived from dredged material. Concentrations of polycyclic aromatic hydrocarbons in earthworms were well below those in soil. 相似文献
563.
An expert system, PASSSFA, has been developed to help select the most appropriate variables for monitoring the effects of extensive land use activities, particularly forestry, on streams. PASSSFA was initially developed for headwater streams in the northwestern U.S. and Alaska, but the consistency of the underlying principles make it much more broadly applicable. The selection process is based on the designated beneficial uses of concern, the type of management activity, accessibility during high flows, frequency of sampling, and the costs for equipment, data collection, and sample analysis. A total of thirty potential monitoring variables are considered, and these were selected because of their sensitivity to land management activities and their effects on key designated uses. Problems in developing PASSSFA and the use of expert systems are discussed. 相似文献
564.
Charles S. ReVelle Justin C. Williams John J. Boland 《Environmental Modeling and Assessment》2002,7(2):71-80
Five classes of zero–one programming models for discrete facility location problems are compared to counterpart models for the selection of conservation reserves. The basic problem of siting facilities to cover demand for services is analogous to the problem of selecting reserves to support species diversity. The classes of models include the set covering and maximal covering models, as well as models for backup and redundant coverage. Issues of reliability and uncertainty are addressed by chance constrained covering models and maximal expected covering models. Exact and heuristic solution approaches are discussed. Multi-objective and economic issues are considered. 相似文献
565.
Bridget N. Bero Margrit C. Von Braun Charles R. Knowles John E. Hammel 《Environmental monitoring and assessment》1993,27(1):17-33
The recognition of the hazards to young children of low-level lead intoxication and the widespread distribution of lead in
the urban environment have resulted in massive federal, state, and local lead awareness and abatement programs. Two of the
most significant exposure routes of lead to young children are the soils and dusts found within the child's home. Most state
and federal lead abatement programs deal with lead-based paint contamination but often do not address the issue of soft-surface
contamination, such as that of carpets, furniture, and draperies. Carpets can be a reservoir of contaminated soils and dusts;
currently, there exists no standard method to test carpeted surfaces for lead contamination.
This paper describes a study that uses X-ray fluorescence (XRF) to test carpeted surfaces for lead contamination. XRF technology
is the standard technology used in lead-based paint testing and is known to be an accurate technique to test for lead in soils.
This study uses a controlled laboratory atmosphere to evaluate this technology; the objectives are to determine: (1) a lower
limit of detection for the instrument; and (2) whether soil loading levels can be differentiated by XRF using trace elements
also present in the soil. Results indicate that XRF can easily differentiate soil loading levels (g soil/m2 carpet). The lower limit of detection of soil lead concentration on the carpet is a function of both soil lead concentration
and soil loading; therefore, lead loading (mg Pb/m2) is a better indicator of detection limit than soil lead concentration. Lead loading detection levels from 108–258 mg Pb/m2 were obtained, as compared to a level of 10 000 mg/m2 (1 mg/cm2) for lead on painted surfaces as required by theLead-Based Paint Poisoning Prevention Act.
XRF technology has the potential to be a fast, inexpensive screening technique for the evaluation of lead contamination on
carpeted surfaces. 相似文献
566.
The NOAA National Status and Trends (NS&T) Program has been monitoring chemical contamination in fish livers, and surface sediments since 1984 and in molluscan tissue and sediments since 1986. Data from fine-grained sediment at 175 sites are used to describe the spatial distribution of contamination throughout the coastal and estuarine United States. Highest levels are generally found in, and considered representative of, urban areas. It should be noted, however, that these levels are not as high as have been found near discharge pipes or in isolated industrial areas through other monitoring efforts. Dramatic biological responses, such as liver tumors in fish or apparently toxic contaminant levels in sediment, are found infrequently. Subtle biological changes, especially those that affect reproductive ability, are being sought. Data from three annual collections of mollusks have been used to identify early signals of temporal trends in contamination at NS&T sites. 相似文献
567.
Charles A. Menzie Jerome J. Cura William F. Skinner 《Environmental monitoring and assessment》1982,2(3):301-308
A realistic approach to thermal impact assessment is presented which employs a two-dimensional thermal plume model, a large data base for river flow and temperature, and accounts for nonuniform spatial distribution of habitats and seasonal differences in fish behavior. The end result portrays real effects of the thermal impact rather than an artificially constructed worst-case scenario. 相似文献
568.
569.