Monitoring of the mediterranean sea pollution (med pol) and data quality assurance

The concerted effort to monitor contaminants and to assess pollution in the Mediterranean Sea was agreed upon by the riverine States with a Programme named MED POL, part of the Barcelona Convention signed up in 1975. For near 25 years, this Programme has been the cornerstone of the Mediterranean Action Plan and has been instrumental to develop the capabilities of the countries to measure and assess marine pollution. Through cooperation with the IAEA Marine Environment Laboratory, in Monaco, which has acted as analytical and training centre for MED POL, hundreds of analysts of the Mediterranean region were trained, equipment was installed and assisted, and analytical techniques to measure pesticides, petroleum hydrocarbons, PCBs, heavy metals, organometallic compounds, and radionuclides in marine samples were tested and adopted. Throughout the years a Quality Assurance programme, which included frequent intercomparison exercises and production of marine reference materials, has also been implemented to improve the comparability of the data. Today, near two thirds of the Mediterranean States implement national marine monitoring programmes to assess water quality and contaminant concentrations. Results of the MED POL programme were embodied in the adoption by the Mediterranean countries of anti‐pollution measures (e.g., emission standards and/or water quality criteria related with mercury, cadmium, radioactive substances, bathing waters, shellfish waters). Trends in marine pollution are shown with data on mussels from the North west Mediterranean and show a reduction of pollutant discharges from land based sources in this area. However, basin wide integrated management of the Mediterranean Sea still requires regional coordinated efforts and increased analytical accuracy in pollution monitoring. The Analytical Quality Assurance has, therefore, a core role in the collaborative assessment of the contamination of the Mediterranean Sea.     

Detection of DNA damage in haemocytes of Mytilus galloprovincialis in the coastal ecosystems of Kastela and Trogir bays, Croatia

Coastal waters are burdened with different contaminants of anthropogenic origin due to intensive urbanisation and economical development. Bays, semi-enclosed areas with limited water renewal ability, are particularly endangered by contaminant inputs. Kastela Bay (Dalmatia, Eastern Adriatic) has earlier been identified as an area loaded with diffuse sources of pollution, including genotoxic agents. However, there is lack of data on the effects of these contaminants on the local marine fauna. The aim of this study was to assess genotoxic impacts in Kastela Bay and the neighbouring Trogir Bay using the micronucleus test and Comet assay with mussel (Mytilus galloprovincialis) haemocytes. Native and caged mussels were included in the studies. Our results confirmed that mussels in Kastela and Trogir Bays are affected by genotoxic contaminants. In addition to mussels from the most known polluted site (Vranjic), there was evidence for genotoxic effects in mussels collected at other locations. The response in the micronucleus test and the Comet assay differed somewhat between sites, the latter apparently being more sensitive, but the two methods complement each other and it is therefore desirable to use them both in monitoring the impacts of genotoxic pollution in coastal waters.     

Metallothioneins (MTs) and delta-aminolevulinic acid dehydratase (ALAd) as biomarkers of metal pollution in great tits (Parus major) along a pollution gradient

Biomonitoring allows an integrated evaluation of different aspects of exposure, accumulation and effects to environmental pollution, simultaneously accounting for the natural variety between individuals in an ecosystem. In this study, the effects of increased metal accumulation were evaluated at the biochemical level in terms of two biomarker responses in the great tit (Parus major), a small insectivorous songbird, along an established metal pollution gradient. Metal concentrations in internal tissues (liver and kidney) and blood indicated that lead and cadmium were the most important metals in the pollution gradient under study. At the biochemical level, induction of metal binding protein metallothionein (MT) in liver and kidney reflected cadmium concentrations in these tissues (R(2)=0.42 and R(2)=0.94 respectively, n=19), although in kidney, MT induction was not sufficient to complex all cadmium present. Secondly, the activity of the enzyme delta-aminolevulinic acid dehydratase (ALAd) in blood decreased exponentially in response to increased lead accumulation (R(2)=0.70, n=18) and represents therefore a specific effect marker for lead exposure. In the highest polluted area, an ALAd inhibition of 85% was reported. Since a higher metal exposure resulted in an increased metal accumulation and subsequent biomarker responses in a dose-dependent way, this study indicates the applicability of ALAd and MT levels in great tits for biomonitoring responses to heavy metal pollution.     

Contaminant flows in urban residential water systems

A contaminant balance for urban residential water systems has been performed for 12 pollutants. The characteristics of the residential site were based on Ellenbrook, a suburb of Perth, Australia. The sources of contaminants were identified and characterised using published literature values. A water balance was used to estimated flow data, and these results were used in conjunction with the contaminant source characteristics to calculate contaminant loads. The contaminants examined were total nitrogen, ammonia, total phosphorus, copper, zinc, lead, cadmium, suspended solids, dissolved solids, chemical oxygen demand, polycyclic aromatic hydrocarbons and oil and grease. Diagrams of contaminant flows through the water, wastewater and stormwater systems are presented. By identifying the sources of contaminants, the diagrams are a useful reference when considering the fate of contaminants in alternative urban water system configurations or how to better handle or reduce these contaminants.     

Models to minimize monitoring

Attempts to monitor changes in the mean concentration of pollutants in estuaries are hampered by the inherent and large seasonal variance induced by the annual pattern of river run-off. Simple models can predict this dilution effect leaving a much smaller variance against which to test for pollution events or gradual changes. An efficient method based on control charts may then be used to test for significant departures from historical performances so enabling a relatively rapid response to be made to undesirable changes. Cumulative sum techniques may also be used to test for inconsistencies between model and calibration data leading to better prediction and therefore more sensitive control of estuarine pollution. These techniques are illustrated using salinity and dissolved cadmium data for the Severn Estuary.     

Spatial and temporal trends and effects of contaminants in the Canadian Arctic marine ecosystem: a review

Recent studies have added substantially to our knowledge of spatial and temporal trends of persistent organic pollutants and heavy metals in the Canadian Arctic marine ecosystem. This paper reviews the current state of knowledge of contaminants in marine biota in the Canadian Arctic and where possible, discusses biological effects. The geographic coverage of information on contaminants such as persistent organochlorines (OCs) (PCBs, DDT- and chlordane-related compounds, hexachlorocyclohexanes, toxaphene) and heavy metals (mercury, selenium, cadmium, lead) in tissues of marine mammal and sea birds is relatively complete. All major beluga, ringed seal and polar bear stocks along with several major sea bird colonies have been sampled and analysed for OC and heavy metal contaminants. Studies on contaminants in walrus are limited to Foxe Basin and northern Québec stocks, while migratory harp seals have only been studied recently at one location. Contaminant measurements in bearded seal, harbour seal, bowhead whale and killer whale tissues from the Canadian Arctic are very limited or non-existent. Many of the temporal trend data for contaminants in Canadian Arctic biota are confounded by changes in analytical methodology, as well as by variability due to age/size, or to dietary and population shifts. Despite this, studies of OCs in ringed seal blubber at Holman Island and in sea birds at Prince Leopold Island in Lancaster Sound show declining concentrations of PCBs and DDT-related compounds from the 1970s to 1980s then a levelling off during the 1980s and early 1990s. For other OCs, such as chlordane, HCH and toxaphene, limited data for the 1980s to early 1990s suggests few significant declines in concentrations in marine mammals or sea birds. Temporal trend studies of heavy metals in ringed seals and beluga found higher mean concentrations of mercury in more recent (1993/1994) samples than in earlier collections (1981–1984 in eastern Arctic, 1972–1973 in western Arctic) for both species. Rates of accumulation of mercury are also higher in present day animals than 10–20 years ago. Cadmium concentrations in the same animals (eastern Arctic only) showed no change over a 10-year period. No temporal trend data are available for metals in sea birds or polar bears. There have been major advances in knowledge of specific biomarkers in Canadian Arctic biota over the past few years. The species with the most significant risk of exposure to PCBs and OC pesticides may be the polar bear which, based on comparison with EROD activity in other marine mammals (beluga, ringed seal), appears to have elevated CYP1A-mediated activity. The MFO enzyme data for polar bear, beluga and seals suggest that even the relatively low levels of contaminants present in Arctic animals may not be without biological effects, especially during years of poor feeding.     

Cholinesterases activities and lipid peroxidation levels in muscle from shelf and slope dwelling fish from the NW Mediterranean: its potential use in pollution monitoring

We selected muscle tissue from nine commercial fish species, seven teleosts and two elasmobranchs, frequently caught in the NW Mediterranean trawling grounds in two different habitats (the continental shelf at 53 m and the slope at 660 m) for cholinesterases (ChEs) characterisation and activities determination, as well as the measure of lipid peroxidation (LP) levels. Acethyl- (AChE), butyryl- (BChE) and propionyl- (PrChE) cholinesterase were chosen as exposure markers of neurotoxic chemicals/molecules and LP as an effect marker of oxidative damage. The use of diagnose inhibitors: eserine sulphate, iso-OMPA and BW284c51 confirmed the measurement of true ChEs as well as the presence of pseudocholinesterases. The present study has evidenced the existence of interspecies differences, especially between teleosts and elasmobranchs but not in relation to depth. Moreover, the good correlation observed between all ChEs in most of the studied fish, supports the use of AChE as neurotoxic marker in field pollution monitoring. The non-metric multidimensional scaling analysis identified the commercial species hake Merluccius merluccius, among teleosts, and the shark, Galeus melastomus, as more adequate sentinel species in commercial fishing grounds. AChE activity showed a relationship with the fish trophic level, while all ChEs revealed a relationship with the feeding habits (benthic, suprabenthic, pelagic) and the stomach fullness. BChE activity and LP levels were the only markers to show a relationship with their swimming capacity.     

Lead poisoning combined with cadmium in sheep and horses in the vicinity of non-ferrous metal smelters

The diagnosis of lead poisoning combined with cadmium in sheep and horses living on farmland in the vicinity of non-ferrous metal smelters in Baiyin of Gansu province in China was based on laboratory findings as well as clinical signs. The concentrations of lead, cadmium, copper and zinc in soils, water, forages, feed and blood, hair and tissues of affected sheep and horses were determined in the surroundings of the smelters in Baiyin and controls. Haematological values were also measured. The concentrations of these elements in soils, forages, water and feed were significantly higher than those in the control area (P<0.01). The contents of lead and cadmium were 9.3 and 690 times in forages, respectively, 10 and 35.6 times in feed. The concentrations of lead and cadmium in blood, hair and tissues of the affected sheep and horses were significantly higher than reference values and control animals (P<0.01). The occurrence of anaemia in affected animals belonged to a hypochromic and microcytic pattern. Lead and cadmium intake levels, estimated according to the ingestion rates of forages, illustrates that the apported lead and cadmium through the ingestion of vegetation growing in the closest sites to the smelters were approximately 6.0 mg Pb/kg body wt./day and 1.1 mg Cd/kg body wt./day in horses, 21.4 mg Pb/kg body wt./day and 4.0 mg Cd/kg body wt./day in sheep, surpassing the fatal dosages for horses of 1.7 mg Pb/kg body wt./day and for sheep of 4.4 mg Pb/kg body wt./day and 1.0 mg Cd/kg body wt./day. It is, therefore, suggested that the disease of sheep and horses in this region is caused by lead poisoning combined with cadmium, mainly due to environment heavy metal pollution by industrial activity. Meanwhile, as such levels of contamination in animal food and grain pose a significant potential risk to human health, these results have formed the basis for subsequent research on levels of metal contamination in human tissues from affected populations. Thus, it can be seen that knowledge of lead and cadmium concentrations in livestock in this region is important for assessing the effects of pollutants on domestic animals themselves and contaminant intakes by humans.     

Trace element and Sigma DDT concentrations in horticultural soils from the Tasman, Waikato and Auckland regions of New Zealand

The long-term routine use of agrichemicals can result in elevated levels of trace elements and persistent organic pollutants in soils. Trace element concentrations and SigmaDDT levels were measured in soil (0-7.5 cm) samples collected from horticultural and grazing properties in 3 regions of New Zealand (Auckland, Tasman and Waikato). Elevated levels of arsenic (<2 to 58 mg kg(-1)), cadmium (<0.1 to 1.5 mg kg(-1)), copper (5 to 523 mg kg(-1)), lead (5 to 243 mg kg(-1)) and SigmaDDT (<0.03 to 34.5 mg kg(-1)) were detected in soils from all 3 regions. With the exception of cadmium and zinc, significantly higher levels of contaminants were generally detected in horticultural soils than in grazing soils. Our results have implications for the on-going use of agrichemicals as concentrations of cadmium, copper, tin and zinc in some samples exceeded ecotoxicity based soil criteria. The p,p'-DDE:DDT ratios indicate that the degradation of DDT in NZ horticultural soils may be inhibited by the co-contamination with trace elements.     

Delineation of Pb contamination pathways in two Pectinidae: The variegated scallop Chlamys varia and the king scallop Pecten maximus

Bioaccumulation of Pb was determined in Chlamys varia and Pecten maximus exposed to ²¹⁰Pb via seawater, food and sediment. Both scallops readily concentrated dissolved Pb with whole-body 7-d concentration factors of 250 ± 40 and 170 ± 70, respectively. In both species, more than 70% of Pb taken up from seawater was strongly retained within tissues (biological half-life > 1.5 month) whereas Pb ingested with phytoplankton was poorly assimilated (< 20%). As P. maximus lives buried in the sediment, this exposure pathway was assessed and showed low bioaccumulation efficiency for sediment-bound Pb (transfer factor < 0.015). Despite the poor transfer efficiency of Pb from food and sediment, the use of a global bioaccumulation model indicated that the particulate pathway (food and/or sediment) constituted the major bioaccumulation route of Pb in both scallops. Whatever the exposure pathway, the digestive gland and kidneys always played a major role in Pb accumulation. In scallop tissues, Pb was predominantly associated with the insoluble subcellular fraction, suggesting a low bioavailability of Pb for scallop consumers.     

The Human Health Effect Programme in Greenland, a review

The burden of persistent organic pollutants (POPs) in Arctic peoples has been monitored for some years. In 1997, the Alta Declaration extended the mandate of the Arctic Assessment and Monitoring Programme (AMAP) to cover assessment of the combined effects of environmental stressors. The AMAP Phase I assessment report (Assessment report: Arctic pollution issues. Arctic monitoring and assessment programme (AMAP), Oslo Norway, xii+859 pp. Vol xii + 859 pp. Oslo, Norway, 1998) gave an overview of the classical toxicology of contaminants. Only recently a programme for measuring the potential biological effects of these contaminants has been established: The AMAP Human Health Effect Monitoring Programme. Body burden data alone are not enough to assess the health risks associated with exposure to environmental contaminants in Arctic peoples. Furthermore, laboratory studies of the effects of single chemicals or chemical mixtures in laboratory animals and cell cultures cannot fully elucidate the human health risks. Integration of epidemiological health research and effect-biomarker studies on humans from exposed populations in the Arctic is needed in order to obtain information about the real health risks resulting from exposure to the accumulated mixtures of contaminants in the Arctic. The present text aims to give a short account of background literature on known and suspected effects of environmental chemicals on endocrine regulated processes with special emphasis on Arctic conditions. Following the evaluation of existing knowledge, a survey of the recently started Human Health Effect Biomarker Programme in Greenland is given.     

Cadmium and zinc accumulation in soybean: A threat to food safety?

A greenhouse study was conducted to quantify cadmium and zinc accumulated by soybean (Glycine max (L.) Merr.) when the metals were supplied separately and together. The highest dose of cadmium (100 mg/kg) reduced plant height and dry weight (down to 40% and 34% of control, respectively); the highest dose of zinc (2000 mg/kg) reduced plant height to 55% of control and dry weight to 70% of control. With both metals present, the plants were approximately the same size as those treated with cadmium only. The concentration of cadmium in the roots was unaffected by zinc. In other tissues, the effect of zinc on the accumulation of cadmium depended on the doses provided. At low doses, the addition of zinc reduced the concentration of cadmium in aboveground tissues to 40-50% of that found in plants exposed to cadmium only. However, when applied in high doses, the presence of zinc in cadmium-contaminated soils increased the uptake and accumulation of cadmium in aboveground tissues by up to 42%. In contrast, at high doses, the presence of cadmium in zinc-contaminated soil resulted in approximately 35% lower concentrations of zinc in all tissues. At a lower dose, cadmium had no effect on concentration of zinc in the plant tissues. The effects of high doses of one metal on the uptake of the other metal can be partially explained by the effects of one metal on the bioavailability of the other metal. In soils to which only one metal was added, bioavailable cadmium was 70-80% of the total cadmium, and bioavailable zinc was 50-70% of the total zinc. When both metals were added to the soil, 80-100% of the cadmium and 46-60% of the zinc were bioavailable. Concentrations of both metals were highest in root tissues (10-fold higher for cadmium, and up to 2-fold higher for zinc). Although relatively little cadmium was translocated to pods and seeds, the seeds of all plants (including those from control and zinc-treated plants) had concentrations of cadmium 3-4 times above the limit of 0.2 mg/kg set by the Codex Alimentarius Commission. This was surprising given that cadmium in the soil was only 1 mg/kg well below the maximum allowable amount for agricultural soil. While it is possible that more cadmium was accumulated by plants in this study than that which might occur under agricultural field conditions, these results reinforce the need to monitor concentrations of toxic metals in food crops.     

Investigation of the significance of heavy metal contents of blackbird feathers

The lead, cadmium and zinc in untreated blackbird (Turdus merula L.) feathers is predominantly of exogenous origin. The endogenous concentration is of minor importance. The degree of surface metal pollution depends on exposure time. The exogenous fraction of heavy metals cannot be completely removed by washing procedures. The difference between washed and unwashed feathers is demonstrated by SEM micrographs.     

A proper choice of route significantly reduces air pollution exposure--a study on bicycle and bus trips in urban streets

A proper selection of route through the urban area may significantly reduce the air pollution exposure. This is the main conclusion from the presented study. Air pollution exposure is determined for two selected cohorts along the route going from home to working place, and back from working place to home. Exposure is determined with a street pollution model for three scenarios: bicycling along the shortest possible route, bicycling along the low exposure route along less trafficked streets, and finally taking the shortest trip using public transport. Furthermore, calculations are performed for the cases the trip takes place inside as well as outside the traffic rush hours. The results show that the accumulated air pollution exposure for the low exposure route is between 10% and 30% lower for the primary pollutants (NO(x) and CO). However, the difference is insignificant and in some cases even negative for the secondary pollutants (NO(2) and PM(10)/PM(2.5)). Considering only the contribution from traffic in the travelled streets, the accumulated air pollution exposure is between 54% and 67% lower for the low exposure route. The bus is generally following highly trafficked streets, and the accumulated exposure along the bus route is therefore between 79% and 115% higher than the high exposure bicycle route (the short bicycle route). Travelling outside the rush hour time periods reduces the accumulated exposure between 10% and 30% for the primary pollutants, and between 5% and 20% for the secondary pollutants. The study indicates that a web based route planner for selecting the low exposure route through the city might be a good service for the public. In addition the public may be advised to travel outside rush hour time periods.     

Inhibition of cadmium-induced hypertension in rats

In a low cadmium environment, adding 10 parts per million (ppm) of cadmium to the drinking water of rats for 3 to 18 months induced increases in systolic pressure averaging 12 to 18 mm Hg. The pressor effect of the cadmium was inhibited by adding 3.6 ppm of selenium or 200 ppm of zinc to the drinking water or by dissolving the cadmium in hard water rather than deionized water. A second experiment with 2.5 ppm of cadmium and smaller amounts of selenium and zinc was confirmatory.Exposure to 10 ppm of cadmium increased renal, hepatic, and cardiac cadmium many fold from barely detectable control levels; however, the increases were much less when the cadmium was dissolved in hard water. Cadmium exposure also increased tissue zinc by 30 to 60%. The addition of selenium to cadmium further increased cardiac cadmium, but the addition of zinc to cadmium had no further effect on tissue cadmium. Tissue selenium concentrations were suggestively bot not significantly higher following selenium exposure. Cadmium alone, or combined with selenium or zinc, increased renal copper; while the combination of cadmium and selenium increased hepatic copper.     

The use of biomarkers to assess the impact of pollution in coastal environments of the Iberian Peninsula: a practical approach

Within the frame of the 2nd Iberian Congress of Environmental Contamination and Toxicology (University of the Basque Country, Leioa, June 1998) a workshop was held about the use of biomarkers in marine pollution monitoring. Among others, the following biomarkers received special attention: metallothionein induction, acetylcholinesterase inhibition, cytochrome P450 system induction, imposex, lysosomal enlargement and lysosomal membrane destabilisation, and peroxisome proliferation. These biomarkers can be used to evaluate exposure to and effect of different contaminants (metals, organic xenobiotics and organometallic compounds) and they can be measured using different methodological approaches (biochemistry, cytochemistry, immunochemical methods based on the use of biotechnology). Before the application of a set of biomarkers in pollution monitoring programmes, well-defined protocols of Quality Assurance have to be established to allow adequate comparison of results. It is also necessary to include analysis of standard reference materials and to obtain detailed knowledge of basal values and seasonal variations of the biomarkers in various species, as well as to integrate the information obtained with the different biomarkers. Marine bivalve molluscs such as mussels are appropriate sentinel species for most of the biomarkers proposed except for the induction of the cytochrome P450 system, which should be measured in fish, and the degree of imposex, which is a biomarker of exposure to TBT specifically measured in certain gastropod molluscs. As a result of the workshop, a battery of biomarkers of contaminant exposure and effects are proposed that could be incorporated into programmes monitoring the quality of the coastal environment in the Iberian Peninsula. These measures would be undertaken in conjunction with chemical measures of contaminant burdens in selected sentinel species.     

Runoff of particle bound pollutants from urban impervious surfaces studied by analysis of sediments from stormwater traps

Runoff sediments from 68 small stormwater traps around the harbor of urban Bergen, Norway, were sampled and the concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), heavy metals, and total organic carbon (TOC) were determined in addition to grain size. Our study provides empirical data from a large area in the interface between the urban and marine environment, studying the active transport of pollutants from land-based sources. The results of the analyses clearly demonstrate the importance of the urban environment representing a variety of contamination sources, and that stormwater runoff is an important dispersion mechanism of toxic pollutants. The concentrations of different pollutants in urban runoff sediments show that there are several active pollution sources supplying the sewage systems with PCBs, PAHs and heavy metals such as lead (Pb), zinc (Zn) and cadmium (Cd). The concentration of PCB7 in the urban runoff sediments ranged between < 0.0004 and 0.704 mg/kg. For PAH16, the concentration range was < 0.2-80 mg/kg, whereas the concentration ranges of Pb, Zn and Cd were 9-675, 51.3-4670 and 0.02-11.1 mg/kg respectively. Grain size distribution in 21 selected samples varied from a median particle diameter of 13 to 646 microm. However, several samples had very fine-grained particles even up to the 90 percentile of the samples, making them available for stormwater dispersion in suspended form. The sampling approach proposed in this paper will provide environmental authorities with a useful tool to examine ongoing urban contamination of harbors and similar recipients.     

Organochlorine pesticides sequestered in the aquatic macrophyte Schoenoplectus californicus (C.A. Meyer) Soják from a shallow lake in Argentina

This study was conducted in Los Padres Lake from Argentina in order to assess the ability of Schoenoplectus californicus to bioconcentrate organochlorine pesticides (OCPs). Bulrush tissues, superficial and near root sediments were collected from the input and the output creek areas. OCP analyses were carried out by GC-ECD. Samples from the input creek area showed the higher OCP levels as a result of contaminants washed down from upstream agricultural fields. Bulrush roots accumulated the highest concentrations of pollutants (30.2-45.7ngg(-1) dry weight). DDTs and chlordanes predominated in sediments and roots besides endosulfan sulfate. The sediments constitute the main source for these OCPs partitioning to bulrush. Stems mainly exposed to water column accumulated preferentially the less hydrophobic pesticides, such as HCHs and endosulfans. We have confirmed the important role of S. californicus in the contaminant removal from sediments. Therefore, this macrophyte can be used as a tool for field studies of OCP pollution monitoring and remediation.     

An investigation of trace element losses during lyophilization of marine biological samples

Trace element losses during lyophilization of selected macroalgae and marine flesh tissues were investigated. No significant losses (p > 0.1) of arsenic, cadmium, copper, iron, mercury, manganese, nickel, lead, selenium, tin and zinc were found. Significant losses of chromium (3–15%) occurred from several specimens. An all-glass freeze drying apparatus is also illustrated.