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Rumbold DG Bruner MC Mihalik MB Marti EA 《Environmental pollution (Barking, Essex : 1987)》1997,96(1):99-105
Tetrachlorodibenzo-p-dioxin (TCDD), tetrachlorodibenzofuran (TCDF) and selected metal concentrations were measured in eggs and nestlings of anhingas (Anhinga anhinga) and white ibises (Eudocimus albus) collected from a colony next to a municipal solid-waste (MSW) combustor and ash landfill. Most of the measured residues, including TCDD, TCDF, arsenic, beryllium, cadmium and nickel, remained at pre-operational levels during the first five years of facility operation. Selenium (in anhingas) and mercury (in both anhingas and ibises) occurred at their lowest concentrations in samples collected during the fifth year of facility operation (Year-5). Alternatively, concentrations of lead in ibis nestlings were highest in Year-1 and Year-5 compared to Year-0. The MSW combustor could neither be ruled out nor confirmed as the source of this lead. 相似文献
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We began monitoring concentrations of both total mercury (THg) and methylmercury (MeHg) in surface water at Stormwater Treatment
Area-2 (STA) on July 20, 2000. This 2602 hectare STA was constructed with three independent marshes to remove phosphorus from
agricultural runoff and reduce eutrophication in the northern Everglades. However, there was concern that in doing so, STA-2
might inadvertently worsen the existing mercury problem in the Everglades. Accordingly, operating permits stipulated that
flow-through operation of these treatment cells could not begin until concentrations of THg and MeHg in the interior marsh
were not significantly greater than corresponding concentrations in the supply canal. Cells 2 and 3 quickly met the start-up
criteria in the fall of 2000. In contrast, Cell 1 exhibited anomalously high MeHg concentrations in the fall of 2000 and 2001,
and the summer of 2002. During the last such event, water-column concentrations in Cell 1 reached 32 ng THg/L and an unprecedented
20 ng MeHg/L. Tissue Hg in resident fishes reached levels as high as 430 ng/g in mosquitofish, Gambusia holbrooki, 930 ng/g in sunfish, Lepomis spp., and 2000 ng/g in largemouth bass, Micropterus salmoides. Guided by results from the monitoring program, flow rate and water depth were managed as a means to alter sulfur biogeochemistry
and, thereby, reduce in situ mercury methylation. This adaptive management strategy likely played a role in the decline in water-column concentrations
of THg and MeHg in Cell 1 by late 2002 and the subsequent declines in tissue Hg levels in resident fishes. Cell 1 finally
met formal start-up criteria on November 26, 2002. 相似文献
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During the 1999 nesting season, eggs and nestlings of anhingas (Anhinga anhinga) and white ibises (Eudocimus albus) were collected from a colony located on the site of a municipal solid-waste (MSW) combustor and analyzed for residues of chemicals potentially released from this facility. Concentrations of most residues, including tetrachlorodibenzo-p-dioxin (TCDD). tetrachlorodibenzofuran (TCDF), arsenic, beryllium, cadmium and lead, were at levels comparable to those found during a similar survey done in 1989, prior to facility start-up. Nickel residues were detected only sporadically in anhingas and in eggs from ibises, and decreased significantly in concentration in ibis nestlings in 1999 compared to 1989. While concentrations of mercury in anhinga nestlings and in eggs of both species were comparable to 1989 levels, its concentration was significantly greater in ibis nestlings in 1999. However, levels of mercury in the ibises remained relatively low when compared to birds from other areas of Florida and did not appear to represent a health threat. While lead did not increase in 1999, its concentration in ibis nestlings remained a concern. The most notable temporal trend observed in birds at this site was a general monotonic decrease in levels of selenium residues during the 10-year monitoring period. 相似文献
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