Costs and benefits of urban erosion and sediment control: The North Carolina experience

The EPA’s new nonpoint source pollution control requirements will soon institutionalize urban erosion and sediment pollution control practices nationwide. The public and private sector costs and social benefits associated with North Carolina’s program (one of the strongest programs in the country in terms of implementation authority, staffing levels, and comprehensiveness of coverage) are examined to provide general policy guidance on questions relating to the likely burden the new best management practices will have on the development industry, the likely costs and benefits of such a program, and the feasibility of running a program on a cost recovery basis. We found that urban erosion and sediment control requirements were not particularly burdensome to the development industry (adding about 4% on average to development costs). Public-sector program costs ranged between $2.4 and $4.8 million in fiscal year 1989. Our contingent valuation survey suggests that urban households in North Carolina are willing to pay somewhere between $7.1 and $14.2 million a year to maintain current levels of sediment pollution control. Our benefit-cost analysis suggests that the overall ratio is likely to be positive, although a definitive figure is elusive. Lastly, we found that several North Carolina localities have cost recovery fee systems that are at least partially self-financing. This article is based on research by the authors for the North Carolina Department of Environment, Health and Natural Resources (DEHNR). The views are those of the research team and do not necessarily reflect the position of DEHNR.     

Arsenic release from pyrite ash waste over an active hydrogeological system and its effects on water quality

Environmental Science and Pollution Research - Arsenic is a potentially toxic element of concern for environmental compartments, and it is a frequent pollutant in many abandoned industrial sites....     

Water quality assessment using remote sensing techniques: Medrano Creek, Argentina

Two spectral bands of the visible spectrum [0.45-0.52 microm (Blue), 0.52-0.60 microm (Green)] of satellite images obtained by LANDSAT 7 ETM+ have been used in this study to follow the contaminated waters of Medrano Creek when it flows into Río de la Plata River. The former is one of the five fresh watercourses going through the Metropolitan Area of Buenos Aires, Argentina, where 13 million people live. Previous studies have shown that the water quality of Rio de la Plata at the outlet of Medrano Creek has decreased more than 50% as a source of water for human consumption. The non-treated effluents of the textile industry probably affect the water quality. We have developed a model that predicts the water quality index (WQI) of surface waters in the study area and uses linear regression analysis. The model has been validated using a data set of 12 physicochemical parameters obtained during the last 3 years. The potentiality of using satellite images was confirmed by the results: (a) to trace the organic contamination (associated with dyes) in freshwater systems and (b) as tools for decision making in the management of water resources.     

Physicochemical and ecotoxicological based assessment of bottom sediments from the Luján River basin, Buenos Aires, Argentina

The physicochemical analysis of bottom sediments of the Lujan River was done on samples from 14 sites situated along its course and covered grain size and organic matter, total N and P, sulfides, heavy metals, organochlorine, and pyrethroid pesticides. In addition, acute 10-day whole-sediment laboratory toxicity tests were carried with each sample, using the native amphipod Hyalella curvispina as test organism. In order to correlate both types of results, data were assessed by multivariate analysis, including principal component analysis (PCA). The physicochemical profile of samples resulted similar along the river course, though several anomalous data were registered in the middle course of the river, mainly in samples taken downstream a large industrial complex; with a few exceptions in upper basin sites characterized by the dominance of agricultural activities, the pesticides concentration were consistently below the analytical detection limits. Almost 50 % of the samples induced adverse effects on the amphipod when testing sublethal and lethal end points. The toxicity of the samples in terms of survival rate was extremely high in two sites, in particular in samples taken downstream the Pilar industrial complex. The integration of a selection of physicochemical and toxicological parameters of the sediments by PCA allowed discriminating areas of the river basin according the type and intensity of their particular pollution condition.     

Microbial secondary metabolites in school buildings inspected for moisture damage in Finland, The Netherlands and Spain

Secondary metabolites produced by fungi and bacteria are among the potential agents that contribute to adverse health effects observed in occupants of buildings affected by moisture damage, dampness and associated microbial growth. However, few attempts have been made to assess the occurrence of these compounds in relation to moisture damage and dampness in buildings. This study conducted in the context of the HITEA project (Health Effects of Indoor Pollutants: Integrating microbial, toxicological and epidemiological approaches) aimed at providing systematic information on the prevalence of microbial secondary metabolites in a large number of school buildings in three European countries, considering both buildings with and without moisture damage and/or dampness observations. In order to address the multitude and diversity of secondary metabolites a large number of more than 180 analytes was targeted in settled dust and surface swab samples using liquid chromatography/mass spectrometry (LC/MS) based methodology. While 42%, 58% and 44% of all samples collected in Spanish, Dutch and Finnish schools, respectively, were positive for at least one of the metabolites analyzed, frequency of detection for the individual microbial secondary metabolites - with the exceptions of emodin, certain enniatins and physcion - was low, typically in the range of and below 10% of positive samples. In total, 30 different fungal and bacterial secondary metabolites were found in the samples. Some differences in the metabolite profiles were observed between countries and between index and reference school buildings. A major finding in this study was that settled dust derived from moisture damaged, damp schools contained larger numbers of microbial secondary metabolites at higher levels compared to respective dust samples from schools not affected by moisture damage and dampness. This observation was true for schools in each of the three countries, but became statistically significant only when combining schools from all countries and thus increasing the sample number in the statistical analyses.     

Ecosystem classification for EU habitat distribution assessment in sandy coastal environments: An application in central Italy

Many recent developments in coastal science have gone against the demands of European Union legislation. Coastal dune systems which cover small areas of the earth can host a high level of biodiversity. However, human pressure on coastal zones around the world has increased dramatically in the last 50 years. In addition to direct habitat loss, the rapid extinction of many species that are unique to these systems can be attributed to landscape deterioration through the lack of appropriate management. In this paper, we propose to use of an ecosystem classification technique that integrates potential natural vegetation distribution as a reference framework for coastal dune EU Habitats (92/43) distribution analysis and assessment. As an example, the present study analyses the EU Habitats distribution within a hierarchical ecosystem classification of the coastal dune systems of central Italy. In total, 24 land elements belonging to 8 land units, 5 land facets, 2 land systems and 2 land regions were identified for the coastal dunes of central Italy, based on diagnostic land attributes. In central Italy, coastal dune environments including all the beach area, mobile dunes and all the fixed-dune land elements contain or could potentially hold at least one EU habitat of interest. Almost all dune slack transitions present the potentiality for the spontaneous development of EU woodlands of interest. The precise information concerning these ecosystems distribution and ecological relationships that this method produces, makes it very effective in Natura 2000 European network assessment. This hierarchical ecosystem classification method facilitates the identification of areas to be surveyed and eventually bound, under the implementation of EU Habitat directive (92/43) including areas with highly disturbed coastal dune ecosystems.     

Decontamination trends in the aquacultured fish gilthead seabream (Sparus aurata) after feeding long-term a PCDD/F spiked feed

Aquacultured fish gilthead seabream (Sparusaurata), previously exposed to low levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) trough the diet for a 13 months period, were fed on a clean feed for another 22 months. Gilthead seabream is a protandrous hermaphrodite species and this “decontamination” period coincided with the stages of sex differentiation, maturity and reproduction of the fish. PCDD/F levels in the fish tissues (i.e. muscle, liver, perivisceral fat and gonads), expressed in pg WHO-TEQ g⁻¹ fresh weight, showed a general decreasing trend during the “decontamination” period. However, this general trend varied among tissues and was also dependent on sex and lipid contents. Toxicological effects affecting fish behaviour and hepatic marker responses were also evaluated. The results pointed out that exposure to PCDD/Fs did not have an impact on fish development and reproduction, since the proportion of sexes found after the sex reversal process was within the normal range described for this species. In addition, long-term exposure to low PCDD/F levels did not significantly affect the response of most of the biochemical markers considered. On the contrary, some of them (e.g. EROD activity) showed variations in their responses during the sex differentiation process and onwards. Finally, the hepatic AhR mRNA levels increased during dioxin exposure but they returned to values typical for non-exposed fish after the “decontamination” period.     

Impact of cypermethrin on stream fish populations under field-use in biotech-soybean production

The impact of biotech-soybean technology on freshwater ecosystems is being evaluated in the Rolling Pampas region, Argentina. The effect of cypermethrin, the main soybean insecticide, on low-order temperate-stream fish populations was investigated for two consecutive crop cycles under field-use conditions in biotech-soybean production. Cypermethrin was unable to induce mortality or behavioral effects on any of the fish species resident in a first-order stream across a crop field (pulsed acute exposure scenario) sprayed according to conventional practices. No spatially or temporally dependent effects were observed on population parameters (size-class structure, abundance, survival, sex and immature/mature ratio, condition factor) of resident or caged Cnesterodon decemmaculatus after spraying or rainfall events, not even one year after, at the beginning of the next crop cycle. Although cypermethrin was "very highly toxic" to C. decemmaculatus in laboratory water (96h-LC(50)=0.43microg/l), its toxicity was reduced in filtered (78%) and unfiltered (92%) stream water. Changes in LC(50) values were mainly correlated with the OC content of each water fraction (r(2)=0.99; p<0.01; n=9), showing that both DOC and TOC contributed proportionally to toxicity reduction. Protective effects of stream water (12-fold reduction LC(50) values) explained the lack of effects on fish populations in the field, despite cypermethrin water concentrations after spraying reached values comparable with the 96h-LC(50). Therefore, cypermethrin under field-use conditions in transgenic-soybean production represents a low risk of acute exposure for fish populations inhabiting low-order temperate-streams rich in TOC. The relationship between LC(50) and TOC could be a convenient way to improve risk estimation based on laboratory toxicity testing.     

Fluoranthene, but not benzo[a]pyrene, interacts with hypoxia resulting in pericardial effusion and lordosis in developing zebrafish

Previous research has documented several PAHs that interact synergistically, causing severe teratogenicity in developing fish embryos. The coexposure of CYP1A inhibitors (e.g. FL or ANF) with AHR agonists (e.g. BaP or BNF) results in a synergistic increase in toxicity. As with chemical CYP1A inhibitors, it has also been shown that CYP1A morpholinos exacerbate BNF-induced embryotoxicity. We hypothesized that a hypoxia-induced reduction in CYP1A activity in BNF or BaP-exposed zebrafish embryos would similarly enhance pericardial effusion and other developmental abnormalities. BaP, BNF, ANF, and FL exposures, both individually and as BaP+FL or BNF+ANF combinations, were performed under hypoxia and normoxia. CYP1A activity in the BaP+hypoxia and BNF+hypoxia embryos was reduced by approximately 60% relative to normoxia embryos. Although CYP1A activity was significantly reduced, we did not observe any increase in pericardial effusion in either group. An unexpected yet particularly interesting result of these experiments was the observed interaction of both FL and ANF with hypoxia. Relatively high, yet environmentally relevant concentrations of FL (100-500 microg L(-1)) interact with moderate hypoxia (7.3% DO) through an unknown mechanism, resulting in pericardial effusion and severe lordosis. Additionally, ANF exposures (100 microg L(-1)) which are not normally teratogenic caused dramatic pericardial effusion, but not lordosis, when embryos were coexposed to hypoxia. These results suggest that reduced CYP1A activity may not exclusively underlie observed developmental toxicity, and that hypoxia may exacerbate the developmental toxicity of some PAH mixtures.     

Analysis of chlorothalonil and degradation products in soil and water by GC/MS and LC/MS

We present a method using gas chromatography (GC) and liquid chromatography (LC) coupled to a mass selective detector to measure concentrations of the fungicide chlorothalonil and several of its metabolites in soil and water. The methods employed solid-phase extraction using a hydrophobic polymeric phase for the isolation of analytes. In lake water, average analyte recoveries ranged from 70% to 110%, with exception of pentachloronitrobenzene that gave low recoveries (23%). The method detection limits were determined to be in the range of 1 and 0.1microg l(-1) for the LC and GC methods, respectively. In soil samples, recoveries ranged from 80% to 95% for 4-hydroxy-2,5,6-trichloroisophthalonitrile (metabolite II) and 1,3-dicarbamoyl-2,4,5,6-tetrachlorobenzene (metabolite III). Limits of detection (LOD) were 0.05 and 0.02microg g(-1), respectively. Chlorothalonil and other metabolites were analyzed by GC giving recoveries ranging from 54% to 130% with LOD of 0.001-0.005microg g(-1).