Assessment of the effectiveness of a novel BioFilm-Membrane BioReactor oil-polluted wastewater treatment technology by applying biomarkers in the mussel Mytilus galloprovincialis

Petrochemical industries and oil refineries are sources of hazardous chemicals into the aquatic environments, and often a leading cause of reduced oxygen availability, thus resulting in adverse effects in biota. This study is an expansion of our previous work on the assessment of the BioFilm-Membrane Bioreactor (BF-MBR) to mitigate the impact of oil-polluted wastewater on marine environments. Specifically, this study evaluated the reduction of selected chemical constituents (hydrocarbons and trace metals) and toxicity related to hypoxia and DNA damage to mussels Mytilus galloprovincialis, before and after treatment of oil-polluted wastewater with the BF-MBR. The application of a multidisciplinary approach provided evidence of the efficiency of BF-MBR to significantly reducing the pollutants load from oily contaminated seawaters. As result, the health status of mussels was preserved by a hypoxic condition due to oily pollutants, as evidenced by the modulation in the gene expression of HIF-1α and PHD and changes in the level of hypotaurine and taurine. Moreover, ameliorative effects in the energy metabolism were also found in mussel gills showing increased levels of glycogen, glucose and ATP, as well as a mitigated genotoxicity was revealed by the Micronucleus and Comet assays. Overall, findings from this study support the use of the BF-MBR as a promising treatment biotechnology to avoid or limiting the compromise of marine environments from oil pollution.

Assessing the Effect of Contaminated and Restored Marine Sediments in Different Experimental Mesocosms Using an Integrated Approach and Mytilus galloprovincialis as a Model

The research presented here was conducted to ascertain the effectiveness of recovery technologies in remediating a compromised marine environment. The multidisciplinary approach aims to integrate traditional chemical-physical analysis and to assess the biological parameters of Mytilus galloprovincialis within different experimental mesocosms (W, G, and B). In particular, this system was designed to reproduce sediment resuspension in a marine environment, which is thought to be one cause of contaminant release. The study combined morphological and ultrastructural observations with DNA damage assessment and mRNA expression of those genes involved in cellular stress responses. The tissues of mussels maintained in the polluted mesocosm showed a higher accumulation of Pb and Hg than in those maintained in restored mesocosm. This observation correlates well with mRNA expression of MT10 and data on DNA damage. The outcome of the biological evaluation consolidates the chemical characterization and supports the concept that the remediation method should be evaluated at an early stage, both to analytically determine the reduction of toxic components and to assess its ultimate impact on the biological system.

Drawing the baseline of trace element levels in the vulnerable Mediterranean osprey Pandion haliaetus: variations by breeding location, habitats, and egg components

Due to its peculiarity to accumulate environmental contaminants, the osprey Pandion haliaetus is a sentinel species for the biomonitoring of contaminants in aquatic ecosystems. Despite this, no information on trace element concentration exists for the Mediterranean area, where relict and vulnerable osprey populations exist. We evaluated the geographical patterns of heavy metals and selenium in osprey eggs from three different populations of the Mediterranean basin (Balearic Islands, Corsica, and Tuscany), to identify any possible contaminant sources. Pattern of metal concentration followed the order: Fe > Zn > Cu > Se > Hg > Pb > Cd. Differences in contaminant concentrations between habitats and among egg components were found. Egg content and inner membrane showed higher mercury levels (1.06 ± 0.89 and 0.67 ± 0.62 mg/kg dw, respectively) than those recorded in the eggshell. Mercury concentration was ca. two times higher in marine than in wetland samples, and even higher (3.6 times) when referred to the eggshell. Cu, Fe, Zn, and Se had higher concentration in the inner membrane. We stress how the choice of the biological material can have significant implications for the correct evaluation of contamination. Our study represents a first regional scale survey for the vulnerable Mediterranean osprey populations and provides baseline data for their long-term biomonitoring.

Trace elements levels in muscle and liver of a rarely investigated large pelagic fish: The Mediterranean spearfish Tetrapturus belone (Rafinesque, 1810)

We determined levels of mercury, cadmium, lead and selenium in muscle and liver of 29 specimens of a large pelagic fish rarely investigated, the Mediterranean spearfish Tetrapturus belone (Raf., 1810). The following element concentration ranking (mean ± S.D.; espressed in mg/kg dry weight) was recorded in muscle: Hg (3.401 ± 1.908) > Se (1.727 ± 0.232) > Pb (0.532 ± 0.322) > Cd (0.019 ± 0.015), and Se (6.577 ± 1.789) > Cd (5.815 ± 3.038) > Hg (2.698 ± 2.214) > Pb (0.661 ± 1.334) in liver. Levels of Hg, Se and Cd were compared to those reported for other Istiophoridae from oceanic areas and for other large predators of Mediterranean Sea, like swordfish and tuna. Organotropism of trace elements and their relation to size was discussed. Ecophysiological considerations regarding the Se-Hg relationship as well as Se-Cd indicate a possible detoxification mechanism. The implications for human consumption are briefly discussed.

Carbonic anhydrase integrated into a multimarker approach for the detection of the stress status induced by pollution exposure in Mytilus galloprovincialis: A field case study

The work was addressed to study the sensitivity of the enzyme carbonic anhydrase (CA) to chemical pollution in the hepatopancreas of the bioindicator organism Mytilus galloprovincialis in the context of a multimarker approach in view of ecotoxicological biomonitoring and assessment application. The study was carried out by means of a transplanting experiment in the field, using caged organisms from an initial population exposed in the field in two areas of interest: Augusta-Melilli-Priolo, an heavy polluted industrial site (eastern Sicily, Italy), and Brucoli (eastern Sicily, Italy) an area not affected by any contamination and selected as a reference site. Mussels in Augusta presented a significant increase in the digestive gland CA activity and gene expression compared to the animals caged in the control site of Brucoli. The CA response in animals from the polluted site was paralleled by proliferation/increase in the size of lysosomes, as assessed by Lysosensor green charged cells, induction of metallothionein, up-regulation of hif-α (hypoxia-inducible factor), metabolic changes associated with protein metabolism, and changes in the condition factor. Biological responses data were integrated with information about sediment chemical analysis and metal residue concentration in animal soft tissues. In conclusion, obtained results highlighted the induction of CAs in the hepatopancreas of Mytilus galloprovincialis following to pollution exposure, and demonstrated its suitability to be integrated into a multimarker approach for the detection and characterization of the stress status induced by pollution exposure in this bioindicator organism.

Organotropism of persistent organic pollutants and heavy metals in the Greenland shark Somniosus microcephalus in NE Greenland

The Greenland shark Somniosus microcephalus is an opportunistic feeder, a top predator, and a very long-lived species. The brain, liver, red and white muscle, gonads, fat, skin, pancreas, and spleen of Greenland sharks from NE Greenland fjords were analysed for PCBs, PCDDs/DFs, PBDEs; DDT isomers; HCH isomers; dieldrin; endrin; HCB; Cd, Hg, Pb, and Se. PCBs (2.01-103 ng/g wet wt) and PBDEs (7.9-3050 pg/g wet wt) were detected in most of the samples. PCDDs/DFs showed high values when detected. DDTs, HCB and HCHs were only detected in some tissues. The ΣTEQ was 5.76 pg/g in muscle. Cadmium mainly accumulated in the pancreas and liver (19.6 and 10.7 mg/kg dry wt, respectively); mercury in red muscle (4.10-6.91 mg/kg dry wt); selenium in the pancreas (3.57 mg/kg dry wt) and spleen (1.95 mg/kg dry wt); lead in the skin (0.358 mg/kgd ry wt). The selenium-mercury ratio in the liver was also evaluated.

Effects of sublethal, environmentally relevant concentrations of hexavalent chromium in the gills of Mytilus galloprovincialis

Hexavalent chromium Cr(VI) is an important contaminant released from both domestic and industrial effluents, and represents the predominant chemical form of the metal in aquatic ecosystems. In the marine bivalve Mytilus galloprovincialis exposure to non-toxic, environmentally relevant concentrations of Cr(VI) was shown to modulate functional parameters and gene expression in both the digestive gland and hemocytes. In this work, the effects of exposure to Cr(VI) (0.1-1-10 μg L(-1) animal(-1) for 96 h) in mussel gills were investigated. Gill morphology and immunolocalization of GSH-transferase (GST), of components involved in cholinergic (AChE and ChAT), adrenergic (TH) and serotoninergic (5-HT(3) receptor) systems, regulating gill motility, were evaluated. Total glutathione content, activities of GSH-related enzymes (glutathione reductase - GSR, GST), of catalase, and of key glycolytic enzymes (phosphofructokinase - PFK and pyruvate kinase - PK) were determined. Moreover, mRNA expression of selected Mytilus genes (GST-π, metallothionein isoforms MT10 and MT20, HSP70 and 5-HT receptor) was assessed by RT-q-PCR. Cr(VI) exposure induced progressive changes in gill morphology and in immunoreactivity to components involved in neurotransmission that were particularly evident at the highest concentration tested, and associated with large metal accumulation. Cr(VI) increased the activities of GST and GSR, and total glutathione content to a different extent at different metal concentrations, this suggesting Cr(VI) detoxication/reduction at the site of metal entry. Cr(VI) exposure also increased the activity of glycolytic enzymes, indicating modulation of carbohydrate metabolism. Significant changes in transcription of different genes were observed. In particular, the mRNA level for the 5-HTR was increased, whereas both decreases and increases were observed for GST-π, MT10, MT20 and HSP70 mRNAs, showing sex- and concentration-related differences. The results demonstrate that Cr(VI) significantly affected functional and molecular parameters in mussel gills, and indicate that this tissue represents the major target of exposure to environmentally relevant concentrations of the metal.

Selective destabilization of tumor cells with pulsed electric and magnetic sequences: a preliminary report

BACKGROUND

Various studies in vitro suggest that low electric and magnetic fields may modify cancer cell growth and recent studies in vivo have revealed anti-tumoral effects. After screening different tumor cell lines, we identified specific sequences of localized magnetic and electric fields (MESQ) that reduce cancer cell survival in vitro. This finding led us to design an experiment to determine the actual efficacy of above sequences in selectively destabilizing tumor cells and their effect on healthy cells.

MATERIALS AND METHODS

We exposed the MCF7 cancer cell line and normal fibroblasts to MESQ for 1, 2, 3 and 6 hours, evaluating cell survival and induction of apoptosis.

RESULTS

Exposure to MESQ reduced MCF7 survival, inducing apoptosis in a timedependent way, whereas fibroblasts were completely unaffected.

CONCLUSION

These results have promising implications for the treatment of cancer and warrant further research.

Sometimes sperm whales (Physeter macrocephalus) cannot find their way back to the high seas: a multidisciplinary study on a mass stranding

Background

Mass strandings of sperm whales (Physeter macrocephalus) remain peculiar and rather unexplained events, which rarely occur in the Mediterranean Sea. Solar cycles and related changes in the geomagnetic field, variations in water temperature and weather conditions, coast geographical features and human activities have been proposed as possible causes. In December 2009, a pod of seven male sperm whales stranded along the Adriatic coast of Southern Italy. This is the sixth instance from 1555 in this basin.

Methodology/Principal Findings

Complete necropsies were performed on three whales whose bodies were in good condition, carrying out on sampled tissues histopathology, virology, bacteriology, parasitology, and screening of veins looking for gas emboli. Furthermore, samples for age determination, genetic studies, gastric content evaluation, stable isotopes and toxicology were taken from all the seven specimens.

The animals were part of the same group and determined by genetic and photo-identification to be part of the Mediterranean population. Causes of death did not include biological agents, or the “gas and fat embolic syndrome”, associated with direct sonar exposure. Environmental pollutant tissue concentrations were relatively high, in particular organochlorinated xenobiotics. Gastric content and morphologic tissue examinations showed a prolonged starvation, which likely caused, at its turn, the mobilization of lipophilic contaminants from the adipose tissue. Chemical compounds subsequently entered the blood circulation and may have impaired immune and nervous functions.

Conclusions/Significance

A multi-factorial cause underlying this sperm whales' mass stranding is proposed herein based upon the results of postmortem investigations as well as of the detailed analyses of the geographical and historical background. The seven sperm whales took the same “wrong way” into the Adriatic Sea, a potentially dangerous trap for Mediterranean sperm whales. Seismic surveys should be also regarded as potential co-factors, even if no evidence of direct impact has been detected.

Mercury, lead and copper in feathers and excreta of small passerine species in relation to foraging guilds and age of feathers

In the present study excreta and feathers of five species of adult passerine birds from Montepulciano wetland (Siena, Italy) were assayed for trace elements between January and August 2006. Lead concentrations varied from 16.31 to 26.50 mg/kg and were found strictly related to the age of feathers. Copper levels were found to be high mainly in insectivorous birds (9.68 mg/kg) and were probably influenced by local use of copper-based agricultural fungicides. Mercury accumulation in feathers varied between species from 0.08 to 0.73 mg/kg. The role offeeding habits on trace elements levels in feathers and excreta is discussed.

Cadmium, lead, and mercury levels in feathers of small passerine birds: noninvasive sampling strategy

Bird feathers have been widely used as a nondestructive biological material for monitoring heavy metals. Sources of metals taken up by feathers include diet (metals are incorporated during feather formation), preening, and direct contact with metals in water, air, dust, and plants. In the literature, data regarding the origin of trace elements in feathers are not univocal. Only in the vast literature concerning mercury (as methyl mercury) has endogenous origin been determined. In the present study, we investigate cadmium, lead, and mercury levels in feathers of prey of Falco eleonorae in relation to the ecological characteristics (molt, habitat, and contamination by soil) of the different species. Cluster analysis identified two main groups of species. Differences and correlations within and between groups identified by cluster analysis were then checked by nonparametric statistical analysis. The results showed that mercury levels had a pattern significantly different from those of cadmium and lead, which in turn showed a significant positive correlation, suggesting different origins. Nests of F. eleonorae proved to be a good source for feathers of small trans-Saharan passerines collected by a noninvasive method. They provided abundant feathers of the various species in a relatively small area--in this case, the falcon colony on the Isle of San Pietro, Sardinia, Italy.

Heavy metals in flamingos (Phoenicopterus ruber) from Italian wetlands: the problem of ingestion of lead shot

Waterbirds are exposed to many contaminants, including lead from ingestion of shot and fishing sinkers. Lead poisoning had never been reported in flamingos wintering in Italian wetlands. Our investigation stems from a case of four flamingos found dead in Tuscany in 2002 with numerous lead shot in their gizzards. We therefore considered other specimens found dead in different Italian wetlands. Many lead shot found in gizzards and lead tissue concentrations confirmed the hypothesis of lead poisoning in two of the seven specimens analysed: concentrations in liver, kidney, and bone were 361.3, 265.09, and 43.31mug/g d.w., respectively. Lead organotropism was typical of acute poisoning. Cadmium and mercury were also determined, and found to be in line with what little data are available on this species in the literature. Although Italy recently endorsed the African-Eurasian Waterbird Agreement (AEWA) prohibiting use of lead shot for hunting in wetlands, our results reveal a first case of lead shot poisoning in flamingos wintering in Italian wetlands. This evidence sounds a further warning of the problem of spent lead shot in countries where hunting in wetlands is not strictly regulated.

Application of a suite of biomarkers in Posidonia oceanica (L.) delile to assess the ecotoxicological impact on the coastal environment

The main aim of this study was to develop and validate a suite of sensitive responses (biomarkers) for monitoring conservation status and ecotoxicological impact in Posidonia oceanica meadows. Analytical methods were developed for NADPH cytochrome c reductase, ethoxycoumarin-o-deethylase (ECOD), guaiacol peroxidase (GPOX) and superoxide dismutase (SOD) assays. A preliminary proteomic approach using 2-D electrophoresis was also proposed as a biomarker. These techniques were initially tested on samples of posidonia exposed experimentally to various contaminants. Once validated, this approach was applied to posidonia in a field study. Samples of the seagrass were collected at four sites with potentially different environmental impact along the northern Tyrrhenian coast. The results showed that reductase activity was significantly induced in the various sampling areas with respect to the reference site. GPOX and SOD showed a similar trend; the highest activities were found in samples collected off a chlor-alkali plant and near a river estuary. Analysis of trace elements, polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds (OCs) in posidonia leaves showed differences between sites. A significant correlation was found between Hg concentrations and GPOX activity and between Cr, Al and As concentrations and reductase activity. The results validated these biomarkers in posidonia for the assessment of ecotoxicological impact on the coastal ecosystem.

Fine structure of the midgut and Malpighian papillae in Campodea (Monocampa) quilisi Silvestri, 1932 (Hexapoda, Diplura) with special reference to the metal composition and physiological significance of midgut intracellular electron-dense granules

The fine structure of the midgut and the Malpighian papillae in Campodea (Monocampa) quilisi Silvestri, 1932 (Hexapoda, Diplura) specimens was described. We observed the presence of electron-dense granules (EDGs) in the midgut epithelial cells, similar in genesis, structure and aspect to the type A spherocrystals described in the midgut epithelium of Collembola and Diplopoda. Energy-dispersive X-ray microanalysis was used to detect the chemical composition of the granules and to relate it to the concentrations of some potential toxic heavy metals (Pb, Cu, Zn) in soil and litter. Chemical composition of the granules seems strongly influenced by the presence and bioavailability of heavy metals in the external environment. Specimens from a contaminated abandoned mining and smelting area (Colline Metallifere, southern Tuscany) were able to accumulate Fe, Mn, Zn, Pb and Cu in their midgut EDGs. In addition, we observed that C. (M.) quilisi was able to excrete the metal-containing granules into the external medium by the moulting of the intestinal epithelium. This confirms that the process of ionic retention of midgut cells is particularly significant in animals lacking Malpighian tubules.

Assessment of toxicological status of a SW Mediterranean segment population of striped dolphin (Stenella coeruleoalba) using skin biopsy

Various studies have revealed high concentrations of contaminants such as organochlorines (OCs) and heavy metals in Mediterranean cetaceans. A geographical trend of contamination (PCBs and DDTs) has been found for striped dolphin (Stenella coeruleoalba). In this study we used a non-lethal approach (skin biopsy) to investigate bioaccumulation of OCs, including polychlorobiphenyls (PCBs), DDTs, polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), trace elements (Hg, Cd, Pb) and CYP1A activity (BPMO) in nine striped dolphins sampled in the Aeolian area (Sicily - Italy) in summer 2002. The arithmetic mean value of BPMO activity in this group was 43.46 AUF/g tissue/h. This value is approximately 3 times and 5 times lower, respectively, than the value found in the Ionian and in the Ligurian groups. Skin biopsies of striped dolphins emerged as a suitable material for assessing the toxicological status of the various Mediterranean groups.

Posidonia oceanica as a biomonitor of trace elements in the Gulf of Naples: temporal trends by lepidochronology

Levels of Hg, Cd, Pb, Cu, Zn, Fe, and Mn were assessed by using Posidonia oceanica as a bioindicator in the Gulf of Naples (southern Italy). Lepidochronology, which enables retroactive dating of scales and rhizomes of this seagrass, was combined with atomic spectrometry to assess temporal trends of trace elements in dated scales and rhizomes over a 10-year period. Lepidochronology occasionally has been used to monitor Hg in dated scales, but never has been used to determine concentrations of other trace elements in dated rhizomes. Data were compared between various structural parts of seagrass and between sampling sites. Concentrations of some elements found in dated scales or rhizomes showed a similar trend in most of the sites; increasing for Hg and Cu and decreasing for Pb, Fe, and Zn. Contaminant levels indicated by seagrass meadows varied from metal to metal. Concentrations of Hg, Cd, and Pb fell within the ranges measured in other areas considered to have low levels of heavy metal pollution, whereas Cu, Mn, and Zn had higher concentrations only in some years. However, on the basis of other studies, none of the sampling sites are considered to have high contamination levels.

The effects of heavy metal contamination on the soil arthropod community of a shooting range

Soils in clay pigeon shooting ranges can be seriously contaminated by heavy metals. The pellets contained in ammunition are composed of Pb, Sb, Ni, Zn, Mn and Cu. The total concentrations of these metals in soils, and the effects of their increasing levels on the arthropod community were investigated at seven sampling sites in a clay pigeon shooting range and compared with two controls. Research revealed that the spatial distribution of Pb and Sb contamination in the shot-fall area was strongly correlated with the flight path of the pellets. Ordination obtained through Redundance Analysis showed that Collembola, Protura and Diplura were positively correlated with major detected contaminants (Pb, Sb), while Symphyla showed a negative correlation with these pollutants. Determination of the soluble lead fraction in soil, and of its bioaccumulation in the saprophagous Armadillidium sordidum (Isopoda) and the predator Ocypus olens (Coleoptera), showed that a significant portion of metallic Pb from spent pellets is bioavailable in the soil and can be bioaccumulated by edaphic organisms, entering the soil trophic network, but without biomagnification.

Review: porphyrins as biomarkers for hazard assessment of bird populations: destructive and non-destructive use

In this review the biochemical, metabolic and toxicological significance of porphyrins in birds is examined, and their use as biomarkers of exposure to xenobiotics and heavy metals is explored. Laboratory studies pinpointing the main classes of compounds that alter porphyrin profiles are described, as well as those which defined the resulting porphyrin profiles and target organs. Field studies in which the biomarker was validated on natural populations of several species of birds are then reviewed. We finally illustrate their potential as a nondestructive biomarker suitable for situations in which destructive sampling of natural populations must be avoided, suggesting the implementation of this approach.

Multi-trial biomarker approach in Meganyctiphanes norvegica: a potential early indicator of health status of the Mediterranean "whale sanctuary."

The aim of this study was to propose a suite of biomarkers (BPMO activity, NADPH-cytocrome c reductase, NADH-ferricyanide reductase. esterases, porphyrins, vitellogenin and zona radiata proteins) and residue levels (organochlorines, PAHs and heavy metals) in the zooplanktonic euphausiid Meganyctiphanes norvegica as a potential multi-disciplinary diagnostic tool for assessment of the health status of the Mediterranean "whale sanctuary". Very little difference in BPMO was detected between sites, with values ranging from 0.75 to 2.68 U.A.F./mg prot/h. On the other hand larger differences between sites were found for reductase activities. Esterases (AChE), porphyrins (Copro-, Uro-, Proto-porphyrins) vitellogenin and zona radiata proteins were also detectable in this zooplanctonic species. Hg showed mean levels of 0.141 ppm d.w., Cd 0.119 ppm d.w. and Pb 0.496 ppm d.w. Total PAHs ranged from 860.7 to 5,037.9 ng/g d.w., carcinogenic PAHs from 40.3 to 141.7 ng/g d.w., HCB from 3.5 to 11.6 ng/g d.w., DDTs from 45.3 to 163.2 ng/g d.w. and the PCBs from 84.6 to 210.2 ng/g d.w.

Assumption and elimination of trace elements in Adélie penguins from Antarctica: a preliminary study

The concentration and distribution of some trace elements were determined in stomach contents, excreta and feathers of Adélie penguins (Pygoscelis adeliae) breeding at Edmonson Point (Terra Nova Bay-Antarctica). In these materials obtained by non-destructive methods, concentrations of mercury, cadmium and lead measured were used to establish natural levels of these metals in the penguins' diet. An intake-excretion hypothesis was formulated.

In vitro study of methylmercury in blood of bottlenose dolphins (Tursiops truncatus)

The biochemical behavior of methylmercury (MeHg) in dolphin blood was investigated in vitro. MeHg distribution between plasma and erythrocytes and its release from erythrocytes into plasma or medium without SH group was determined. At the subcellular level its distribution among different thiol-containing molecules was also investigated in erythrocytes and plasma. When blood was treated with 0.1 mM MeHg, about 98.1% was found in red cells and 1.9% in plasma; only 0.6% of MeHg present in the cellular compartment was bound to membranes. Hemoglobin (Hb) and albumin, principal proteins containing SH groups (PSH), and glutathione (GSH) appeared to be the main targets of MeHg in dolphin blood. Gel filtration of stroma-free hemolysate of treated red blood cells (RBCs) revealed that MeHg was almost equally present in high (52.5%) and low (47.5%) molecular weight fractions, whereas in plasma it only eluted with proteins (high molecular weight fractions). Hemoglobin was identified as the main intracellular protein binding MeHg. The exchange reaction of MeHg between GSH and dolphin hemoglobin was also evaluated and the equilibrium constants calculated.

Porphyrin levels in excreta of sea birds of the Chilean coasts as nondestructive biomarker of exposure to environmental pollutants

In this preliminary study on sea birds we propose the use of porphyrins in excreta as a biomarker of exposure to contaminants. Samples of excreta were obtained from colonies of brown pelicans (Pelecanus occidentalis thagus), neotropic cormorants (Phalacrocorax olivaceus), and kelp gulls (Larus dominicanus) in three areas of the south coast of Chile with different human impact (Tubul, Talcahuano, and Valdivia). They were analyzed for porphyrin content (copro-, uro-, and protoporphyrins and total porphyrins) by a rapid fluorimetric method and by HPLC. The main outcomes of the study were: (a) kelp gulls and neotropic cormorants living in areas with high human impact showed a clear capacity to accumulate and eliminate porphyrins in the excreta; (b) species-related accumulation capacities are likely, as shown by the different levels found in different species living in the same area; (c) the porphyrin profile obtained by fluorimetry and HPLC showed a higher percentage of protoporphyrin than the other porphyrins; (d) although the fluorimetric method of Grandchamp is semiquantitative, it was found to be sensitive enough to detect differences in samples from field studies. The positive results of this preliminary study make it possible to propose this nondestructive method for a variety of field applications.

Trace elements in striped dolphins (Stenella coeruleoalba) from the western Mediterranean

Tissues obtained from Stenella coeruleoalba stranded along the Spanish and Italian Mediterranean coasts from 1987 to 1994 were analysed for cadmium (Cd), copper (Cu), mercury (Hg), selenium (Se) and zinc (Zn). The age, length and weight of the dolphins were recorded. Hg levels were also assayed in skin biopsies from dolphins of the same species in the waters off northeastern Spain and in the Tyrrhenian and Ligurian Seas. Levels of all elements differed in muscle of stranded dolphins from the two areas. Hg was higher in tissues from animals stranded on the Italian coasts and in skin biopsies obtained in the Tyrrhenian and Ligurian Seas, than in the respective Spanish samples. This is probably related to Hg pollution from the natural weathering of cinnabar ores in central Italy. Se and Cd levels had similar accumulation patterns to those of Hg. Accumulation of Hg and Se is explained by the existence of a detoxification pathway involving both elements, however the reason for the similar Cd trend is unclear. Geographical differences in the accumulation pattern of these elements may reflect the existence of two different populations of Stenella coeruleoalba in the western Mediterranean.

Chlorinated hydrocarbons in the tissues of South Polar Skuas (Catharacta maccormicki) and Adélie Penguins (Pygoscelis adeliea) from Ross Sea, Antarctica

High rates of egg infertility and embryo death in a colony of South Polar Skuas breeding in the Antarctic were similar to those in polluted North Atlantic populations of the Great Skua. Such loss could not be linked to factors such as organochlorine pollutants, as levels of DDE and PCBs in the contents of skua eggs from the population were only a small fraction of those in polluted skua populations from the Northern Hemisphere. Average eggshell thickness for skuas nesting on Ross Island has shown no significant change since the introduction of DDT. Concentrations of DDE and PCBs in South Polar Skuas were 13 and 22 times higher, respectively, than those in the eggs of sympatric Adélie Penguins, and this probably reflects the greater exposure of skuas to pollution when they migrate north of the Antarctic Convergence in winter. Residues in liver tissue showed a similar trend, and a higher rate of mixed function oxidase induction in skua liver compared to that of penguins is consistent with the trends seen in pollutant levels. The same PCB congener predominated in both skua and penguin samples. Comparisons with historical residue data suggest that global levels of DDT residues are declining.

Multiresponse biomarker evaluation of interactions between methylmercury and Arochlor 1260 in quail

The single and combined effects of methylmercury and Arochlor 1260 were investigated in experimental quail treated chronically with the two compounds at low and high doses. A series of metabolic and biochemical biomarkers were evaluated together with mercury and PCB accumulation to pinpoint the effects of treatment with one or both chemicals. Methylmercury alone was associated with a decrease in serum cholesterol. Less PCBs were accumulated in tissues when Arochlor 1260 was combined with methylmercury than when the former was administered alone. Liver monooxygenase (MFO) activity was depressed 50% more in the presence of methylmercury than with Arochlor 1260 alone. Single or combined treatment with high doses of the two compounds resulted in similar degrees of DNA damage. This approach was found to provide a good picture of the interaction between environmental contaminants.

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 γ-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 23'44'5 (IUPAC number 118) and the hexachlorobiphenyl 22'344'55' (PCB-153); in birds 22'44'55' (PCB-180) prevailed.

Porphyrins as biomarkers of methylmercury and PCB exposure in experimental quail

Chemicals such as heavy metals and polyhalogenated hydrocarbons have a high capacity to interfere with the enzymatic processes responsible for haem biosynthesis. These compounds can produce accumulation in tissues and organs and increased elimination of porphyrins in excreta (Andrew et al, 1990). The development of fast and easy analytical methods and the wide variety of biological media in which porphyrins can be detected have suggested their use as biomarkers of environmental pollution (Akins et al, 1993; De Matteis and Lim 1994). The analysis of porphyrins in the excreta is of special interest because it enables nondestructive monitoring of wild animals in the assessment of threatened or endangered species (Fossi et al, 1994). Methylmercury and PCBs are ubiquitous global pollutants and there is evidence they accumulate in terminal consumers, particularly those belonging to marine trophic chain (Renzoni et al, 1986; Yamashita et al, 1993). There have been some reports on methylmercury-induced (e.g. Woods et al, 1991; Bowers et al, 1992; Miller and Woods 1993) and PCB-induced porphyria (e.g. Vos and Pennings, 1971; Miranda et al, 1987; Elliot et al, 1990; Miranda et al, 1992) but little data on their combined effect. In order to investigate the quality of porphyrins as biomarkers we performed an experiment in which Japanese quail were fed a diet containing methylmercury and polychlorobyphenyls (PCBs as Arochlor 1260) individually or combined in different ratios. The present study aims to provide preliminary data on liver and fecal levels of porphyrins in response to methylmercury and PCB administration, and on whether the indicator is sensitive to synergism or antagonism between the two compounds, administered simultaneously.

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.

Blood esterase inhibition in birds as an index of organophosphorus contamination: field and laboratory studies

: With the aim of developing a nondestructive biomarker (serum 'B' esterases) for monitoring bird populations exposed to azamethiphos S((6-chloro-2-oxooxazolo(4,5-b)pyridin-3(2H)-yl)methyl) 0,0-dimethyl phosphorothioate (9Cl), parallel laboratory and field studies were performed. In japanese quail (Coturnix coturnix japonica) treated with azamethiphos at 10 mg kg(-1), serum butyrylcholinesterase (BChE) and carboxylesterase (CE) activities were inhibited by 88% and 35%, respectively, after 24 h. A gradual recovery was observed after 48 and 72 h. With a higher dose (50 mg kg(-1)), the birds died, or were killed 3 h after dosing. Serum BChE and brain acetylcholinesterase (AChE), in birds that were sampled at 3 h, were inhibited by 98% and 92%, respectively. Hepatic microsomal and serum CEs were also inhibited. There was a statistically significant correlation (r=0.9808, p<0.001) between the activities of serum BChE and brain AChE. Swallows (Hirundo rustica) nesting in a stable treated with azamethiphos showed a drastic reduction in BChE (56%) and CE (36%) 24 h after treatment of the stable.

The differential modulation of the enzymes of glutathione metabolism. Indication of overlapping effects of toxicity and repair in mouse liver and kidney after dietary treatment with methyl mercury and sodium selenite

The effect of methylmercury (MM) and MM plus sodium selenite (SE) on the activity of various GSH-dependent enzymes was studied in the liver and kidney of mice. Ten groups of mice were fed diets containing graded proportions of MM, alone or with graded quantities of SE. GST, GSH-Px, and GSSG-RED were assayed in the cytosolic fraction of liver and kidney homogenates. After treatment with MM, instead of the expected decrease in enzyme activities, an increase was observed in the kidney and a small decrease in the liver with no dose-response relation in either organ. In protected groups, a general pattern of induction was observed in both organs, but again there was little evidence of dose-response relationships. Detailed analysis of the results suggests that the effects observed were not directly caused by MM or SE but are the resultant of complex interactions presumably related to contemporaneous mechanisms of damage and repair.

Trace elements and chlorinated hydrocarbons in eggs of Pelecanus crispus, a world endangered bird species nesting at Lake Mikri Prespa, North-western Greece

Eggs of the Dalmatian pelican, Pelecanus crispus, collected from 1984 to 1986 at Lake Mikri Prespa, north-western Greece, contained residues of trace elements and PCBs at low concentrations, and of DDE at rather high concentrations. DDE is negatively related to eggshell thickness. Eggshell thickness was reduced by 12-20% in comparison with the pre-1947 (before DDT use) eggshell thickness. However, this decrease did not affect the reproductive success of this species. The main fish species eaten by the Dalmatian pelican at Lake Mikri Prespa were analyzed for pollutants. All the fish contained low concentrations of residues. The contribution of the diet while the birds are on the wintering grounds is unknown. Recommendations for a monitoring programme of pollutants in eggs of the Dalmatian pelican, a world-endangered species, are proposed.

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.

Long term monitoring of pollutants in eggs of Yellow-legged Herring Gull from Capraia island (Tuscan Archipelago)

Chlorinated hydrocarbons (hexachlorobenzene, lindane, pp'DDE, polychlorinated biphenyls) and trace elements (Hg, Se, Cd, Pb) were determined in eggs of Yellow-legged Herring Gull (Larus cachinnans) collected in an island of the Tyrrhenian Sea during the period 1981-1986. PCBs levels vary on the average between 30.4μg g(-1) d.w. in 1981 to 56.1 μg g(-1) d.w. in 1983. The capillary chromatograms revealed the presence of about 30 somers of PCBs without significant variations in the eggs of the same year; more than 50% of the residues is made up only three isomers: the 22'44'55', the 22'344'5' and the 22'344'55'. Average DDE residues were 7-8 times lower than those of PCBs and declined during the period (from 9.2 μg g(-1) d.w. in 1981 to 4.5 μg g(-1) d.w. in 1986). Cadmium and lead are present in low concentrations. The average levels of mercury and selenium are around 2-2.5 μg g(-1) d.w., and a cumulative correlation, on a molar basis, exists between these two elements.

Complementary accumulation of selenium and mercury in fish muscle

The concentrations of total selenium and total mercury in the muscle of striped mullet from four stations in the Northern Tyrrhenian Sea and one in the Black Sea were analyzed. If the sum of the concentrations of mercury and selenium (expressed as nmoles/g) is plotted against the age of the specimens, a single function describes all of the results. The explanation suggested by the authors is that Se-Hg receptors exist and increase with the age of the animal. These receptors may be occupied by mercury in proportion to its concentration in the environment.

Heavy metals in organisms from the northern Tyrrhenian sea

The concentrations of zinc, manganese, copper, cadmium, lead and mercury have been determined in soft tissues of four marine organisms (Mytilus galloprovincialis Lmk., Nephrops norvegicus L., Mullus barbatus L., Engraulis encrasicolus L.) collected seasonally from the winter of 1976 to the spring of 1980 in various areas of the Tyrrhenian Sea (western Mediterranean). In all four species levels of all metals, except mercury in all areas are alike while mercury levels vary and, furthermore, are higher than in specimens from other areas of the Mediterranean and also from other seas. The possible natural origin of the mercury from cinnabar (HgS) ore as well as the suitability of the four species as bioindicators is discussed.