Evaluation of toxicity and sex-related variation of PCB levels in Mediterranean striped dolphins affected by an epizootic

Individual PCB congener concentrations, including non-ortho chloro substituted, were determined in 30 striped dolphins (Stenella coeruleoalba) affected by the 1990–1992 Mediterranean epizootic to investigate their toxic potential. PCB congener concentrations in these dolphins were among the highest ever found in comparable studies on marine mammals. Concentrations in males and females were significantly different because of pollutant transfer to offspring by females. Thus, PCB concentrations and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalents (TEO) in males were approximately double those in females. Non-ortho, mono-ortho and di-ortho coplanar congeners accounted for approximately one third of the overall toxicity assessed through toxic equivalent factors (TEFs), as defined by Ahlborg et al. (1994). Di-ortho congener 170 and non- ortho congener 126 were the major contributors to TEQ (33% and 30% respectively).     

Variations in polychlorinated biphenyl congener composition in eggs of Mediterranean water birds in relation to their position in the food chain

The concentrations of the principal PCB congeners and the SigmaPCB were determined in eggs of eight species of water birds collected in two areas of the Mediterranean region. The results for SigmaPCB levels indicate statistically significant differences between the species; in the Po delta the higher values are for those species which feed mainly on fish. Differences exist between the congeners and their percentages when compared with the total residue. Tetrachlorobiphenyls constitute a larger proportion of the SigmaPCB in Avocet and Black-winged Stilt, two species whose diet consists mainly of invertebrates. The main component in all the species is 22'44'55' and its presence varies between 11.4% in Avocet and 21.2% in Audouin's Gull. It is suggested that there is a link between the uptake of PCBs and the position of the species in the food chain.     

An integrated ecotoxicological approach to assess the effects of pollutants released by unexploded chemical ordnance dumped in the southern Adriatic (Mediterranean Sea)

In order to gain preliminary knowledge about the threat to marine ecosystems due to leakage of chemical warfare agents (CWAs) and other pollutants from rusting bombshells on the seabed, a case study was conducted in a dumping area in the southern Adriatic Sea (depth 200–300 m). Following electroacoustic and magnetometric surveys of the CWA dumping area, an integrated ecotoxicological approach was used. This approach was based on analysis of CWA residues and their metabolites, including arsenic, in sediment and organisms, as well as multimarker methodology including the Health Assessment Index, histological lesion analysis and enzyme assays. Two sentinel species were selected, the blackbelly rosefish [Helicolenus dactylopterus (Delaroche, 1809)] and the European conger (Conger conger L., 1758). Sediment analysis revealed the presence of CWA degradation products, including 1-4-thioxane and 1-4-dithiane. Tissues of fish from the CWA dumping site showed higher levels of arsenic than those from the reference site. Neither CWAs nor their metabolites were detected in fish tissues. Arsenic levels recorded in blackbelly rosefish were well above those reported for other fish species from the southern Adriatic, much higher than the FDA limit for food (2.6 mg kg⁻¹) and close to the LD₅₀ calculated for mammals (20 mg kg⁻¹ body weight). The presence of pollutants in the CWA dumping site was also confirmed by pathological lesions in both species and EROD activity, two to three times higher than in fish from the reference site (16.45±8.08 and 8.05±5.87 pmol min⁻¹ mg protein⁻¹ in blackbelly rosefish and 269±24.92 and 78.71 pmol min⁻¹ mg protein⁻¹ in European conger, respectively). Cholinesterase activity seemed unaffected in muscle of both species, whereas in brain they were one-third of those recorded in fish from the reference site (14.22±10.05 and 72.87 nmol min⁻¹ mg protein⁻¹, respectively). This suggests that acetylcholinesterase is sensitive to CWAs. In conclusion, the agreement of all the chemical and biological parameters investigated suggests that the integrated ecotoxicological approach used is appropriate to reveal the presence and biological effects of CWAs in the marine ecosystem. Physical and Chemical Impacts on Marine Organisms, a Bilateral Seminar in Italy–Japan held in November 2004.     

Interspecies differences in mixed function oxidase activity in birds: Relationship between feeding habits, detoxication activities and organochlorine accumulation

The relationship between feeding habits and interspecies differences in the detoxication ability of the mixed function oxidase (MFO) system was investigated in birds. The role of MFO (particularly aldrin epoxidase activity) in the detoxication/bioaccumulation of organochlorines was also investigated. Euriphagic (yellow-legged herring gull (Larus cachinnans), black-headed gull (Larus ridibundus), jackdaw (Corvus monedula), magpie (Pica pica) and stenophagic (cormorant (Phalacrocorax carbo), coot (Fulica atra) and sparrow (Passer italiae)) species were collected in northern and central Italy. The following liver microsomal monooxygenase activities were measured: aldrin epoxidase, ethoxyresorufin dealkylation (EROD), benzyloxyresorufin dealkylation (BROD) and pentoxyresorufin dealkylation (PROD). NADPH-and NADH-cytochrome c reductase (NAD(P)H-CYT-CRED) and NADH-ferricyanide reductase (NADH-FERRIRED) activities were also measured in the liver microsomal fraction. Glutathione concentration (GSH) was measured in the liver cytosolic fraction. As a marker of liver damage gamma-glutamyl transpeptidase (GGTP) activity was assayed in the serum. The residues of organochlorines (HCB, pp'DDTs and PCBs) were determined in muscle samples. Omnivorous species, particularly the yellow-legged herring gull, had the highest aldrin epoxidase activities. In the yellow-legged herring gull the activity was approximately twice as high as in the jackdaw (p < 0.05), black-headed gull (p < 0.05) and coot (p < 0.05). Values five times lower were detected in the specialist fish-eater, the cormorant (p < 0.001). The lowest values of aldrin epoxidase activity were detected in the sparrow. Feeding habits were found to be related to evolutionary interspecies differences in MFO activity. A significant statistical correlation (r = 0.656) was found between the 'omnivore index' and MFO detoxication activity expressed as aldrin epoxidation. Organochlorines, and particularly PCBs, were higher in cormorants and yellow-legged herring gulls from a polluted lagoon than in the other species analysed (black-headed gull p < 0.01; sparrow p < 0.001; jackdaw p < 0.01; coot p < 0.001). Levels of pp'DDE were much higher in the cormorant and sparrow than in the other birds. Knowledge of the different species-specific detoxication abilities was found to be a useful tool for the identification of species potentially at risk in environments with high pollution by chlorinated hydrocarbons, or in general contaminants metabolized by the MFO system.     

Persistent organochlorine residues in fish and water birds from the Biobio river,Chile

Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites, HCH isomers and hexachlorobenzene (HCB) were determined in fish and birds from different locations in the Biobio river basin (central Chile). Samples collected near the mouth of the river contained high concentrations of PCBs, reflecting the massive use of these xenobiotics in the urban and industrial areas of Concepcion and Talcauano. Samples collected in the central part of the basin contained very high concentrations of lindane that coincide with the widespread use of lindane-based pesticides (purified -HCH) in this area. DDT was distributed homogeneously throughout the basin, except at Laguna Icalma, the source of the river in the Andes. Most PCB residues in fish and birds consisted of congeners between penta- and hepta-chlorobiphenyls. In fish, the predominant congeners were the pentachlorobiphenyl 23445 (IUPAC number 118) and the hexachlorobiphenyl 2234455 (PCB-153); in birds 224455 (PCB-180) prevailed.     

Calculation of the unit emergy value of water in an Italian watershed

Emergy is a thermodynamics-based entity that enables the implementation of a holistic environmental accounting system. It contributes to identify and measure all the inputs (energy and matter) supporting a given system, expressed in a common unit, namely solar emergy joule (sej). The emergy per unit product (called unit emergy value, UEV), is a measure of the environmental cost of a given resource. It is specific of the system/process and gives information on the dynamics, components and functioning of it. This paper presents the emergy evaluation of water resources within the watershed of the river Sieve, located in the Province of Florence (Italy). Along the river, an artificial basin has been created by means of a dam to preserve water quantity and quality, and to protect the Florentine area from dangerous floods and inundations. Different UEVs of water can be identified along the course of the river, especially upstream and downstream of the dam. These values quantify both the environmental and human efforts made to ensure and regulate the presence of water at different points of the river. The UEV of water flowing in the river increases from 1.35 × 10⁵ sej/g upstream, to 5.80 × 10⁵ sej/g downstream of the dam, depending mainly on man-made infrastructure. Along the watershed, three different systems of extraction, purification and distribution of water have been chosen on the basis of their dimension, type and location. UEVs of water distributed and the emergy investment necessary to implement different water management strategies are presented. The value of water purified and distributed decreases from 2.00 × 10⁶ sej/g for the smallest plant in the mountainous area, to 1.72 × 10⁶ sej/g for the largest plant, in the city of Florence, depending on production efficiency.     

A protocol for the evaluation of genotoxicity in bile of carp (Cyprinus carpio) exposed to lake water treated with different disinfectants

A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20 d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO₂) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20 d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C₁₈ silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always showed a genotoxic activity as compared to the control group. The results of this study provide evidence that all three disinfectants cause an increase in bile genotoxicity of chronically exposed fish.     

A combinated approach to investigate the biochemistry and hydrography of a shallow bay in the South Adriatic Sea: the Gulf of Manfredonia (Italy)

The main goal of this study is to understand the hydrological and biochemical set up and processes of a marine coastal area located in the western side of the south Adriatic sea (the gulf of Manfredonia) by the use of both satellite images and in situ investigations A water sampling in the gulf of Manfredonia was performed at 18 fixed stations in June 2003; physico-chemical and biological parameters (temperature, salinity, dissolved oxygen and fluorescence) were measured along the water column and water samples were collected to analyse dissolved nutrients (ammonia, nitrite, nitrate, phosphate and silicate), total nutrients (nitrogen and phosphorus), chlorophyll a and total suspended solids. Surface spatial distributions of field collected data were examined to characterize biochemical and hydrographic conditions of the Gulf of Manfredonia and these results were related with the remote sensing analysis data. Remote sensed data (obtained by Landsat 7 TM and Modis Terra) were processed to obtain maps of chlorophyll a, temperature and optical characteristics of the gulf; these maps were compared to in situ data. From physico-chemical measurements no stratification was observed in the water column except for the south-eastern area. High concentrations of silicate and ammonia were observed in the northern zone of the gulf, while nitrate, phosphate, chlorophyll a and total suspended solids distributions showed higher values in the central coastal zone. These results were confirmed by remote sensing analysis; Modis elaboration showed a distribution with higher concentrations of chlorophyll a near the coast and Landsat images highlighted the extension of the surrounding agricultural areas crossed by the two main rivers which discharge into the gulf. The integration between field data with the remote sensing analysis showed to be a valid support in coastal zone management.     

Satellite-based indices in the analysis of land cover for municipalities in the province of Siena, Italy

Territorial indicators based on the satellite measured reflected or emitted energy can provide valuable information on the spatial evolution of a territory. Information regarding land use, biomass coverage and radiant temperature were obtained from remotely obtained measurements for each municipality in the Province of Siena. Remotely sensed data were combined into different indices to compare characteristics of land cover between territories and create an information base for continued study. A classification was performed on a municipal level and land use classes were grouped together and a general index of use pressure was created. A vegetation index was used to compare biomass densities. A radiant temperature index was calculated using measure thermal infrared emissions. The results of these analyses allowed researchers to examine the intra and inter-municipal spatial heterogeneity within the Province. A comparison between the results of each index was made and the problems related to the use of such indices were examined.