Heavy metal analysis in fish‐kill cases in rivers in Guipuzcoa (Spain)∗

Some fish‐kills in Basque rivers were studied by gill tissue analysis: Samples were wet digested and the solution was analyzed by atomic absorption spectroscopy. In three cases, the cause was linked to the effluents of an aluminium anodizing factory, cyanide caused one kill and copper wastes were related with another. Three cases were attributed to natural reasons and one of the kills was of unknown origin.     

Geochemical forms of trace metals in mangrove sediments—Red Sea (Egypt)

Seven sediment samples from mangrove sediments of the Red Sea were taken in order to evaluate the possible contamination of the sediments by trace metals (iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), lead (Pb) and cadmium (Cd)). Sequential extraction techniques were performed to study the different geochemical forms of these metals. X-ray diffraction analysis has been performed to correlate the mineralogical composition with the geochemical forms of the studied elements. The results of Fe and Mn contents indicate that they are in large part from lithogenous origin. The elevated concentrations are associated with the residual form ranged from 70 to 93% for Fe and 46 to 70% for Mn. The percentage of Zn, Cu, Cd and Pb in the non-residual form was much greater than that of the residual fractions. This reflects the high mobility and bioavailability of these metals in mangrove sediments of the Red Sea. X-ray diffraction analysis revealed the presence of silicate components including quartz, feldspars and clay minerals in some locality. Non-silicate components recorded in the study area as calcite as well as, Mg-calcite. Quantitatively both components i.e. silicate and carbonate varied according to their source material.     

Speciation of particulate trace metals in sediments of Anarbe reservoir∗

Total concentration and chemical forms of heavy metals in samples of sediment from a drinking water reservoir have been analysed. The result of total metal contest shows Fe and Mn concentration increase along the reservoir, from 4.4% in Fe and 0.07% in Mn in the end part to 6.4% Fe and 0.22% Mn at the dam. However, a decrease in organic matter along the reservoir is observed. In order to test the accuracy of the digestion methods used, a standard reference material was also analysed.

Trace metal concentrations, with exception of Cadmium, Pb and Mn, found in fraction 5 are higher than those observed in the others extractions, Fe, Ni, Zn, Cr and Cu content in non‐residual fraction is found mainly in moderately reducible fraction, but the percentage of this fraction in each metal is very different.     

Seasonal AVS–SEM relationship in sediments and potential bioavailability of metals in industrialized estuary, southeastern Brazil

In anoxic sediments, as those found in estuaries, the mobility of metals can be controlled by the formation of stable sulfide complexes. The potential bioavailability of a metal can then be predicted on the basis of the acid volatile sulfide (AVS) and simultaneously extracted metals (SEM) criterion. Distributions of AVS and SEM (Hg, Cu, Pb, Cd, Zn, and Ni) along the sediment profiles were determined seasonally for three rivers that constitute the Santos-Cubat?o estuarine system (SE Brazil), which is located in one of the most industrialized areas of Latin America. AVS and SEM concentrations varied significantly, from 0.04 to 31.9 μmol g⁻¹ and 0.086–6.659 μmol g⁻¹, respectively. The highest AVS levels in sediments were detected in the winter, whereas high SEM values predominated in the summer. Considering SEM–AVS molar differences as a parameter to evaluate potential bioavailability, sediments nearest to the industrial area represent higher risk to biota, especially during the summer. It is due to relatively low AVS values and not necessarily high concentrations of metals.     

Cadmium,zinc, copper and Metallothionein in human tissues (liver and kidney)∗

It was proved by in vitro and animal experiments, that the toxicokinetics (resorption, distribution, deposition and excretion) and, in connection with this, also the toxicity of the metals Cadmium (Cd), Copper (Cu) and Zinc (Zn) is closely associated to the low molecular weight protein Metallothionein (Mt). There is a considerable lack of information on the Mt concentration in human tissues and its correlation to Cd, Cu and Zn. Therefore the concentrations of Cd, Cu, Zn and Mt were determined quantitatively in liver and kidney samples of 184 deceased. The dependence of these concentrations from each other and from further parameters, i.e. age, sex, drinking and smoking habits, or diseases of the organs, is studied. Scalar values (concentrations, age) were compared by Spearman rank correlations. The influence of non‐scalar factors (i.e. sex, diseases etc.) was proved by comparison of the geometric means of the Cd, Cu, Zn and Mt concentrations in the tissues of the corresponding subgroups. The manner of influence of the main factors will be discussed.     

Quantifying plant pigments and live diatoms in aphotic sediments of Scandinavian coastal waters confirms a major route in the pelagic–benthic coupling

The fate of pelagic diatoms in marine coastal aphotic sediments was investigated from sediment profiles in western Scandinavian waters. We used three independent methods to estimate pigment pools in the sediment: (1) fluorometry, (2) high-performance liquid chromatography and (3) pigments estimated from germinable diatom cells, using the dilution extinction method. A strong positive relationship with an intercept close to zero was observed between fucoxanthin, a marker of diatoms, and chlorophyll a. The fucoxanthin/chl a ratio was on average 1.05, which was similar to monocultures of dominating diatom taxa, indicating that sedimentary chl a was to a large extent of diatom origin. Chl a and fucoxanthin correlated significantly and positively with, and where within the same order of magnitude as, corresponding substances predicted from live diatom cell numbers obtained with the dilution extinction method. This indicates that a major part of surficial sediment chl a was bound in live cells of pelagic diatoms. There was a consistent change in viable cells with sediment depth and with timing of dominating taxa, with the non-spore-forming Skeletonema costatum dominating in the surface sediment in March and May, while the spore forming Chaetoceros spp. dominated deep in the sediment and during periods outside of the spring bloom (February and August). This indicates that chl a is bound in several different cell pools with different degradation rates, depending on diatom taxonomy. Thus, diatoms originating predominantly from the spring bloom may provide an important direct link in the pelagic–benthic coupling in this area.     

Accumulation, contamination, and seasonal variability of trace metals in the coastal zone – patterns in a seagrass meadow from the Mediterranean

Amongst a plethora of threats to seagrass ecosystems, contamination with heavy metals may well be one of the most significant. We therefore set out to track contamination levels with Cu, Zn, Pb and Cd in the principal autotrophic compartments and sediments of a meadow of Posidonia oceanica in the Gulf of Naples, Mediterranean Sea. With respect to metal levels, leaves and their associated epibiota are certainly not a homogenous compartment, as might perhaps be inferred from the common use of the term “leaf–epiphyte complex” in the literature. Save for Cu, all metal species analysed showed appreciable differences in concentration between seagrass leaves and epibiota. These results give strength to our argument that in ecotoxicological work leaves and epibiota should not be treated as a single unit. Although absolute differences in trace-metal levels among sampling periods varied somewhat with the specific component analysed (i.e. macrophyte organs, epibiota, sediment), an overall trend of markedly higher heavy-metal levels during the winter season is a striking one. Whilst annual cycles in growth dynamics of the seagrasses explain a significant fraction of the temporal variance, seasonality in productivity is a doubtful explanation for similar patterns in non-living sedimentary components; consideration of additional variables therefore seems sensible. As variables with consistent explanatory powers we suggest: (1) seasonal cycles in storm frequency and amplitude which remobilise metals bound in the sediments of the sea floor, and (2) increased precipitation during the cold season which may significantly increase marine metal levels through elevated weathering of rocks and elevated fluvial inputs of anthropogenic contaminant loads. Whereas Cd and Pb concentrations in seagrass leaves from the Gulf of Naples fall within the range for coastal areas subjected to low levels of heavy-metal pollution, Cu and Zn reach levels typical of highly contaminated regions, such as the waters bordering major coastal cities. Any direct comparisons of the pollution status of seagrass beds between different geographic areas are, however, likely to be confounded by the indiscriminate application of the “leaf–epiphyte complex”: the magnitude of the confounding effect depends on the ratio of epibiota/leave biomass, time of sampling, and metal species analysed. Received: 15 May 1997 / Accepted: 2 February 1998     

Sustainable coastal communities in the age of coastal storms: Reconceptualising coastal planning as ‘new’ naval architecture

Hurricanes devastated the Gulf coast of the USA in 2005. Hurricane Katrina, in particular, highlighted the compelling need to build more sustainable and hazard-resilient communities. Much can be learned from recovery efforts to rebuild the Gulf coast. Personal observations and interviews with planners, academics and others involved in recovery efforts inform this analysis, which focuses on New Orleans. A conceptual framework is developed and principles and operational imperatives outlined to guide action for building sustainable, hazard-resilient communities. Such communities will remain elusive unless ‘business as usual’ is confronted by a transformational process of developmental planning. Sustainable, hazard-resilient coastal communities are founded upon robust ‘critical infrastructure’ that is secured by planning and decision-making processes that enable coastal communities to build ‘layers of resilience’ to overcome ‘waves of adversity’. Planners need to take on a redefined role—as ‘new naval architects’—to design and build communities that are ‘sea-worthy’ in this age of coastal storms.

Trace metals in the western Mediterranean Sea∗

Data on Cd, Pb and Cu concentrations in seawater referring to five years of field studies on the western Mediterranean Sea are reported in order to present a space and time integrated situation on the levels of these metals. Surface total metal concentrations present rather homogeneous distributions between the different areas considered, including the Tyrrhenian Sea. The metal concentrations in three areas affected by natural and industrial wastes are also discussed. The vertical distribution of the dissolved Cd, Pb and Cu in the Alboran Sea seems to be rather homogeneous, both vertically and among the stations chosen between the Strait of Gibraltar and the Island of Alboran.     

Accumulation and transfer of Hg, As, Se, and other metals in the sediment-vegetation-crab-human food chain in the coastal zone of the northern Brazilian state of Pará (Amazonia)

The high consumption of crabs (Ucides cordatus) stimulated interest in the present study on the northern coast of Brazil, which encompasses a preserved area of mangrove forest. The objective was to describe and quantify the transfer of metals from the muddy sediments to the leaves of the Rhizophora mangle, and thence the crabs and humans. The samples were collected along two transects, while samples of hair were obtained from local habitants. The pH, interstitial salinity, Eh (mV) were measured, the granulometry and mineralogical and multi-element chemical analyses were run, and the organic material determined. The sediments are silty-clayey, composed of quartz, kaolinite, iron oxides, and illite, as well as smaller portions of smectite, pyrite, halite, and high levels of SiO₂ (56.5 %), Al₂O₃ (18.5 %), and Fe₂O₃ (7 %). The elements Zn, Sr, As, and Zr are concentrated in the leaves, while the bioaccumulation of Zn, Se, Sr, and As was recorded in the crabs, of which, Se is the most concentrated in the tissue of the muscles and the hepatopancreas. The concentrations of nutrient and toxic elements were similar in all age groups (hair samples), with only Hg presenting an increasing concentration between infants and adults. The highest rates of transfer were recorded for the elements Zn and Se in the crabs and Hg in leaves and hair. The accumulation of metals in the leaves and crabs reflects the chemical composition of the sediments and low rates of sediment-vegetation-crab transfer, with the exception of Hg, which accumulated in the hair.     

Speciation of heavy metals in suspended particulates in urban air†

An anayltical procedure based on a sequential extraction scheme is applied to samples of suspended particulates from an urban area of Barcelona. This area presents high levels of air pollution owing to automotive emissions and industrial activity.

The procedure allows the partitioning of particulate trace metals into four fractions: soluble and exchangeable, bound to carbonates and iron‐manganese oxides, bound to organic matter and residual. In this work, the chemical associations of Fe, Pb, Cu, Mn, Cr and Cd have been investigated.

In the analysed samples, only the cadmium is predominantly in the first fraction whereas the other metals are largely associated to carbonates and Fe‐Mn oxides.     

Source and Distribution of Heavy Metals in Food†

Diet is the major route of exposure to contaminants, therefore food monitoring programs are essential to estimate the degree of human risk. We present a study undertaken in Austria dealing with the total uptake of mercury, cadmium, arsenic and lead. The dates were calculated from diet as well as from commercial food. Higher contaminated foodstuffs are registered and a comparison was made between body burden of babies and adults on the basis of bodyweight. It was pointed out, that cooked or washed food ready to eat has a lower burden of lead and cadmium than non prepared food due to household processing, which may decontaminate food to some extent’ Arsenic content was not reduced, because it is bound chemically and not primarily deposited on the surface of food such as in the case of lead. It was mentioned that the type of compound plays an important role in the assessment of action of those elements on humans.

Their biological activity is not necessarily related to their concentration in food. As in the case of selenium and chromium one has to take into consideration that there is a narrow range between benefit and harm, toxicity, and minor supply.

Therefore we conclude, that due to interactions of elements, their different biological activity and due to the difference of compounds present in food, we have to relativate the terms toxicity and essentiality. Then we can get a more profound insight into the problems of trace elements in food.     

Chromosome damage in individuals exposed to heavy metals†

Testing the mutagenic activity of environmental pollutants has become an important area of modern environmental science and prophylactic medicine. The most suitable method for short‐term mutagenicity testing on man, at present, are chromosome studies on somatic cells of exposed individuals. Mutation types analyzed by such studies are of high practical relevance as indicator system of genetic damage induced in man under in vivo conditions. A rather large series of such studies has been dedicated to the action of heavy metals on individuals contacted with these metals under therapeutic, ecological or occupational conditions or by intoxication. Lead, cadmium, chromium, nickel, mercury, zinc and other metals as well as their compounds have been under study. Analyses of that kind, of course, are hampered by difficulties with the distinct estimation of the actual load as well as unclear conditions of exposition, e.g. simultaneous exposition to different metals.

Results obtained till now arouse some suspicion of a direct or indirect mutagenic activity in man by certain chromium and platinum compounds, arsenic, mercury, and combinations of lead with other heavy metals (cadmium, zinc, arsenic, antimony, etc.). Life style, above all smoking habits, well may act comutagenic. In most cases, however, mutagenic activity of metals and metal compounds apparently is clearly superposed by their toxic activity. In specific cases, chromosome studies also may contribute to discover sources of ecological exposition and to monitor occupational load by heavy metals.     

Heavy metal characteristics in Ko?ani Field plant system (Republic of Macedonia)

Heavy metal contamination of soils is widespread and induces a long-term risk to ecosystem health. This research focuses on the heavy metal contamination, transfer values and risk assessment in the Ko?ani Field plant system (Republic of Macedonia). To identify the heavy metal concentrations in Ko?ani crops (rice and maize), the geochemical analysis was performed by inductive coupled plasma mass spectrometer and thereupon the transfer factor (TF) and estimated daily intake amount values were calculated. The highest As, Cd, Mo, Pb and Zn values were determined in the rice samples grown in the paddy fields near the Zletovska River. The highest Pb and Mo concentrations measured in the maize samples were from the maize fields near the Zletovska River and Ciflik city. High TF values for Mo, Zn, Cd and Cu revealed a strong accumulation of Mo, Zn and Cd by rice and Mo and Zn by maize crops. The results of the estimated daily intake showed that the regular consumption of rice and maize crops containing the highest Cd, Mo, Pb and Zn concentrations could pose a serious threat to human health, because the daily intake of Cd, Mo, Pb and Zn for crops grown in the fields around the Zletovska River exceeded the recommended provisional tolerable daily intake values. Taking into account the results, the area around Zletovska River is considered as the most anthropogenically impacted part of Ko?ani Field.     

Organic carbon and environmental quality of riverine and off-shore sediments from the Gulf of Cádiz,Spain

Here we show that heavy metal geoaccumulation is apparent in the Tinto and Odiel estuary and, at a lower magnitude, in off-shore sediments. Values above probable effects level (PEL) are recorded for As, Cu, Hg, Pb and Zn in the Tinto and Odiel estuary, for As and Hg in the associated off-shore sediments and for As in the Guadiana River. Significant correlations were found between total organic carbon (TOC) and Cr, Cu, Ni and Zn in the Tinto and Odiel estuary, and Cr, Cu, Ni, Pb, Hg and As in the Guadiana River. PCA analysis differentiated the three studied locations.     

Trace metals in “ Posidonia oceanica ” seagrass from south-eastern Sicily

Heavy-metal concentrations were measured in sediments and tissues of Posidonia oceanica seagrass from south-eastern Sicily (Italy) in order to assess the degree of metal pollution in the coastal area. Seagrasses and sediments were collected at four sites along the south-eastern coast of Sicily. Flame atomic absorption spectrophotometry (FAAS) was used to measure concentrations of Cu, Zn, Cd and Pb. Standard statistical analyses were used to assess significant differences among the levels of the elements measured in different tissues and sediment and spatial distribution. The greatest values of potentially toxic metal concentrations were observed at the station near the industrial sites of Augusta and Priolo. Comparisons with the concentrations of the same metals in other sites of north and western Sicily and with data from surveys in other areas of the Mediterranean Sea are shown.     

Metal associations in anoxic sediments and changes following upland disposal†

The ecological effects of heavy metals in contaminated sediments are more determined by the chemical form and reactivity than by the level of accumulation. Dredging of anoxic sediments and disposal on land is attended by changes of redox conditions. Under oxidizing conditions some controlling solid compounds may change gradually thus changing the solubility of certain metals.

Chemical extraction experiments for estimating characteristic association forms of heavy metals in anoxic sediments were carried out, both under presence and absence of air during the analytical procedure. Drying of the sediment decreases the proportion of the sulfidic metal fractions to a stronger degree, and oxidized Cd and Zn are found in the most available, exchangeable fraction.

With respect to long‐term effects acidification of poorly buffered sludges after disposal on land is probably the most important factor affecting metal associations and mobility. For many metal examples a linear relationship has been found between decreasing pH values and increasing dissolved metal concentrations. To quantify these relationships and for better comparison of samples a simple test procedure is proposed which is based on pH differences before and after addition of acid.     

Metal speciation in sediments of polluted and non‐polluted lakes

A five‐step extraction procedure for metal speciation studies (copper, lead, nickel, manganese and zinc) was applied to the analysis of lake sediments characterised by different environmental features. A different partition of metals into the several metal forms was observed. Both the metal fraction sorbed or co‐precipitated on hydrous Mn‐oxides (especially lead and zinc) and that bound to organic matter (especially copper) are high in some samples. A prevalently anthropogenic origin of these metals may be hypothesised on the basis of existing knowledge of the equilibrium and change phenomena occurring among water, particulate and sediments. Conversely, the non‐solubilised forms of metals are abundant in the sediments of lakes that are certainly not polluted. The concentration of manganese is very high in the sediments of Antarctic lakes; sequential extractions show its lithogenic origin. In conclusion, a knowledge of the different types of metal associations in sediments and their percentage can facilitate understanding of both natural and anthropogenic metal enrichment of aquatic systems.     

Mercury distribution in the sediments of Ambarlı Port Area,Sea of Marmara (Turkey)

The purpose of this study is to investigate historical and current mercury (Hg) contamination in the surface and core sediments of the Ambarl? Port area. Textural parameters, total organic carbon (TOC), ²¹⁰Pb and total Hg (THg) contents were measured. Mercury contamination of the sediments was assessed on the basis of the enrichment factor (EF), anthropogenic factor (AF), index of geoaccumulation (Igeo) and corresponding sediment quality guidelines. Most surface sediment samples were also non-toxic with mercury concentrations below the effects range-low (ERL) value, but mercury levels at five stations were between ERL and effects range-median (ERM) values, where occasional adverse effects concerning risk analysis are expected. The EF and Igeo analysis showed that there was no significant mercury enrichment and contamination in the core sediment before the 1650s, but values increased from then onwards to 2009 (being especially accelerated in line with port activities from 1989), disclosing a serious ecotoxicological risk to sediment-inhabited marine organisms.     

Interactions between metals accumulated in the narrow-clawed crayfish Astacus leptodactylus (Eschscholtz, 1823) in Dikilitaş Lake,Turkey

The accumulations of Al, Cd, Cr, Cu, Fe, Ni, Pb and Zn in the exoskeleton, gills, hepatopancreas and abdominal muscles of crayfish Astacus leptodactylus (Eschscholtz, 1823) were determined. The strongest correlation observed was between Cr and Ni in the gills (r?=?0.904); moderate to strong correlations between Al, Cr, Fe, Ni and Cu were also observed in gill tissue. Disregarding the gills, the strongest correlation was found between Cu and Zn in the hepatopancreas (r?=?0.808); the correlation between these two metals might have been a result of metallothionein activity. The accumulation of Pb was found to correlate with that of Cd in the exoskeleton, Cd and Zn in the gills, Zn and Cu in the hepatopancreas and Cu in the abdominal muscle. None of these correlations were present in lakewater and sediment samples, suggesting that the crayfish metabolism may be responsible for the co-accumulation of metal–metal pairs. As all correlations in non-gill tissues are observed between divalent metals, a shared transporter such as divalent metal transporter 1 might be involved in the accumulation of these metals.