Haematological status of wintering great tits (Parus major) along a metal pollution gradient

In the long-term biomonitoring of wild populations inhabiting polluted areas, the use of non-destructive biomarkers as markers of condition is very important. We examined the possible effects of metal pollution on the haematological status of adult great tits (Parus major) along a well-established pollution gradient near a non-ferrous smelter in Belgium. We measured blood and feather metal concentrations and assessed the haematological status (amount of red blood cells, haemoglobin concentration, haematocrit, mean corpuscular volume and mean corpuscular haemoglobin) of adult great tits during winter at four study sites. Metal concentrations in blood and feathers indicated that cadmium and lead were the most important metals in the pollution gradient under study. Measurements of haematological parameters revealed that haemoglobin concentration, haematocrit, mean corpuscular volume and mean corpuscular haemoglobin were lower in great tits from the more polluted sites. These parameters were significantly negatively correlated with blood lead concentration. The amount of red blood cells, however, did not significantly differ among study sites. Our results indicate that the haematological status of great tits is negatively affected by metal pollution and may therefore be used as a successful biomarker for monitoring the negative impact of metal exposure in the wild.     

Accumulation and effects of metals in caged carp and resident roach along a metal pollution gradient

Metal accumulation and effects on plasma Ca(2+), alanine transaminase (ALT) and fish condition factor were examined in caged carp (Cyprinus carpio) and resident roach (Rutilus rutilus) at four locations along the Grote Nete River system (Belgium). Cadmium and zinc accumulation were found in carp and roach, with highest concentrations at the most contaminated site (dissolved Cd: 1.82 microg/l, Zn: 967 microg/l). On the tissue level, highest cadmium concentrations were measured in kidneys of carp and roach, followed by gills, intestine and liver, while low concentrations were observed in carcass and muscle. For zinc, a similar pattern was observed (intestine>kidney>gills>liver>carcass>muscle). Comparison between species showed higher cadmium concentrations in feral roach, while zinc levels were lower, owing to the high zinc concentrations in control carp. Furthermore, comparison of metal concentrations between two sampling periods (2005 and 2000-2001) revealed a drastic decrease in cadmium concentration in gills, liver and muscle of roach, similar to the reduction in waterborne cadmium concentrations, while differences for zinc were much less pronounced. In addition to metal accumulation, increased metallothionein concentrations (approximately 2x) were found in carp and roach, while no metal-related effects were found on ALT, Ca(2+)or condition factor. However, negative effects on fish community structure, as assessed by the index of biotic integrity (IBI), were found along the pollution gradient and indicated long-term adverse effects of metal pollution.     

Heavy metal accumulation in the periwinkle Littorina littorea, along a pollution gradient in the Scheldt estuary

Inductively coupled plasma atomic emission spectrophotometry (ICP-AES) was used to determine heavy metal concentrations in the shells and soft tissues of the periwinkle Littorina littorea, collected at seven sites along the Scheldt estuary. Several metals accumulate in the animals soft body parts, and are related to the seawards decreasing pollution gradient. No clear correlation with a previously detected shell size patterning could be established.     

Diversity and structure of Chironomidae (Diptera) communities along a gradient of heavy metal contamination in a subarctic watercourse

Community structure of chironomid larvae was investigated along a gradient of heavy metal pollution in the subarctic lakes of the Pasvik watercourse, bordering Northern Norway and Russia. Sixty taxa were present in the four investigated lakes. Species richness was lower in Lake Kuetsjarvi, nearest the main source of pollution, relative to the more distant lakes, and Simpson's diversity index was similarly highest in the less polluted site with higher maximum depth. The number of orthoclad chironomid species was considerably higher at the least contaminated sites, whereas the relative abundance of Orthocladiinae was highest at the most polluted site. Chironomid density increased with increasing distance from the main source of heavy metal pollution, especially in the subfamilies Tanypodinae and Chironominae, and total chironomid biomass was significantly higher at the least polluted site. Canonical correspondence analysis revealed spatial patterns consistent with species-specific tolerance to the heavy metal concentrations. Protanypus morio, Monodiamesa bathyphila, Chironomus spp., Polypedilum scalaenum gr. and Sergentia coracina seemed to be tolerant to heavy metal contamination, occurring most commonly at the most polluted sites. In contrast, Heterotrissocladius subpilosus, Psectrocladius semicirculatus/sp., Chironomus anthracinus, Pagastiella orophila, Cladotanytarsus iucundus, and Tanytarsus spp. appeared to be more sensitive taxa, being common at the least polluted sites, but rare or absent at the two sites close to the pollution sources. Densities of Procladius (Holotanypus) spp., Tanytarsus spp. and Chironomus anthracinus were negatively correlated with heavy metal concentrations and these taxa appeared to be the best indicators of heavy metal contamination.     

Effect of the delta-aminolevulinic acid dehydratase gene polymorphism on renal and neurobehavioral function in workers exposed to lead in China

Effects of delta-aminolevulinic acid dehydratase (ALAD) polymorphisms on the renal and neurobehavioral functions were investigated in Chinese workers from a storage battery plant exposed to inorganic lead. Blood and urine were collected from each worker to determine the ALAD genotypes, blood lead levels (PbB), urinary β2-MG and urinary NAG activity. The World Health Organization Neurobehavioral Core Test Battery (WHO-NCTB) was used. Of the 135 lead workers tested for ALAD genotype, 126 were ALAD1-1, 9 were ALAD1-2 but none were ALAD2-2. The gene frequencies of ALADl-1 and ALADl-2 were 93.33% and 6.67%, respectively. The workers with ALAD1-2 genotype had significantly higher concentrations of PbB (62.52 µg/dl vs. 41.02 µg/dl), urinary NAG (22.01 U/gCr vs. 13.49 U/gCr), urinary β2-MG (194.98 μg/gCr vs. 112.88 μg/gCr), and digit span backward (DSB) score (6.67 vs. 5.33) than those of ALAD1-1 genotype. Urinary NAG of ALAD1-2 genotype carriers was significantly higher than that of ALAD1-1 genotype under the same blood lead level (b_i 0.75 vs. b_i 0.29). Interaction between PbB and ALAD genotypes has a significant influence on NAG (P = 0.02) and β₂-MG (P = 0.01). It is postulated that the workers with the ALAD2 allele appear to be more susceptible to the effects of lead on renal injury, whereas neurobehavioral functions in ALAD1 homozygote tend to be more vulnerable.     

Lead concentration and delta-aminolevulinic acid dehydratase activity in the blood of the general population of Tarragona Province, Spain.

Blood samples were collected from 488 people living in an industrial and an agricultural area of Tarragona Province, Spain. The samples were subjected to blood lead analyses by atomic absorption spectrophotometry. Although in the industrial area men had higher blood lead levels than women, this difference was not statistically significant. Blood lead concentrations were related to a range of factors such as age, smoking and drinking habits. Both smoking and drinking habits were associated with a dose-dependent increase in blood lead levels, especially in men. On the other hand, delta-aminolevulinic acid dehydratase (ALA-D, EC 4.2.1.24) activity was determined in blood from 186 people of Tarragona Province. The results obtained were within the normal limit values (NLV) as defined by the WHO. The present data concerning Tarragona Province show that in relation to environmental health there is not a serious problem from lead contamination.     

Interspecific comparison of cadmium and zinc contamination in the organs of four fish species along a polymetallic pollution gradient (Lot River, France)

The impact of cadmium (Cd) and zinc (Zn) discharges related to an old zinc ore treatment facility in the Lot River (France) was investigated in four fish species (the chub: Leusciscus cephalus, the roach: Rutilus rutilus, the perch: Perca fluviatilis and the bream: Abramis brama). The organisms were sampled in four stations along the polymetallic contamination gradient. Cd and Zn analysis were carried out in five organs (gills, posterior intestine, liver, kidneys and skeletal muscle) in order to highlight the potential pathways of uptake, storage and elimination of metals. The results indicate a very strong Cd contamination in fish collected downstream from the metal source. The kidneys have the highest cadmium concentrations, but the gills and the intestine, as exchange organs, present the largest variations between the stations in close relation with the contamination gradient. Cd concentrations measured in the liver vary only slightly among the sampling stations. Unlike the trends observed for Cd, Zn levels in fish populations are strongly regulated and do not follow ambient Zn concentrations. The concentrations measured vary also according to fish species, for both Cd and Zn. This study shows that the trophic habits can explain the interspecific differences in Cd bioaccumulation. Zn levels observed for each species in non-contaminated populations also help to understand metal bioaccumulation patterns in polluted sites, suggesting that the determinism of interspecific differences is constitutive.     

Use of Polytrichum formosum (moss) as a passive biomonitor for heavy metal pollution (cadmium, copper, lead and zinc)

After sampling over regular intervals from 1985 to 1987 the heavy metals Cd, Cu, Pb and Zn were quantitatively determined by atomic emission spectrometry/inductively coupled plasma in above-ground parts of the moss Polytrichum formosum (Hedw.). All metals present a typical summer-winter oscillation (seasonal variation), which is much greater than the "inter-stand" variation of Polytrichum formosum within the forest ecosystem under investigation. To obtain comparable results on a regional or global scale it is suggested to collect all samples of Polytrichum formosum for biomonitoring purposes in the last week of September.     

Introduction of cAMP and establishment of neutral lipids alterations as pollution biomarkers using the mussel Mytilus galloprovincialis. Correlation with a battery of biomarkers

The results of the present study suggest that the signaling molecule cAMP could constitute a reliable biomarker of pollution monitoring. Increased levels of cAMP were observed in tissues of mussels Mytilus galloprovincialis exposed to PAHs, 2,4-dichlorophenoxyacetic acid and lindane for 15 days. cAMP levels were higher in mantle/gonad complex, in relation to other tissues studied (digestive gland and gills). In support of our suggestion, cAMP was significantly correlated with established biomarkers, such as lysosomal membrane stability, AChE activity and metallothionein content. In addition, our results support the establishment of morphometrical alterations of neutral lipids as biomarker of organic pollution, since high accumulation of neutral lipids in the digestive gland of mussels exposed to organic pollutants in relation to non-exposed mussels was noted. In addition, correlation analysis between cellular and biochemical biomarkers showed that the volume density of neutral lipids negatively correlated with both lysosomal membrane stability and AChE activity. Regarding micronucleus test, our results do not support its use as a biomarker of organic pollution, since no statistical differences were found between control and exposed mussels. On the other hand, significant correlations were observed among the battery of biomarkers, such as lysosomal membrane stability, AChE activity and metallothionein content after the mussels' exposure to the specific organic compounds, thus supporting the important role of these biomarkers as reliable indicators of organic pollution. In conclusion, our results support cAMP and morphometrical alterations of neutral lipids as biomarkers of environmental pollution.     

Monitoring metal and metalloid bioaccumulation in Hydropsyche (Trichoptera, Hydropsychidae) to evaluate metal pollution in a mining river. Whole body versus tissue content

Whole body metal concentration is easier to analyse than concentration in tissues, but is often not an accurate measure of the potential toxicity of the metal. We tested if whole body metal and metalloid concentrations in the caddisfly Hydropsyche (Trichoptera, Hydropsychidae), common in a mine-polluted river (Guadiamar River, SW Spain), were a useful measure to extrapolate environmental degradation. Our results confirmed that metal and metalloid accumulation by Hydropsyche strongly correlated with metal and metalloid concentration both in the water and the sediment, and also correlated with macroinvertebrate community parameters such as total richness and abundance, as well as the richness of some taxonomic groups (EPT and OCH). Seven elements were analysed, Zn, Cu, Pb, As, Cd, Tl and Sb; only As did not show significant correlations. In addition, after leaving live organisms in clean water for 24 or 48 h, we found that 24 h were sufficient to clean the gut content and that between 33% and 75% of the whole body metal content were concentrated in this organ. Although concentration in tissues also discriminated between control and affected stations, we found better results with whole body concentrations when evaluating environmental quality.     

Wild boar hair (Sus scrofa) as a non-invasive indicator of mercury pollution

This paper investigates the usefulness of wild boar (Sus scrofa) hair as a non-invasive indicator of mercury pollution. Samples were collected in two hunting seasons (1998/1999 and 1999/2000) by hunters from four differently polluted regions of Poland. Mercury content was determined by AAS methods. Different washing procedures were compared. De-ionised water was found to be suitable for the removal of exogenous mercury sources in hair analysis. Metal distribution along hair was analysed. It was found that problems arising from differences in distribution of metal along a single hair strand as well as differences in the hair colour can be eliminated through the careful homogenisation of the samples before analysis. The influences of physiological, ecological and environmental factors that might significantly affect the obtained results (age, gender, season, location of habitat and diet of the sampled animals) were estimated and taken into account. The present study revealed that female hair contained a higher amount of mercury than male hair. Moreover the highest mercury content was found in young individuals between 1 and 2 years of age. A positive correlation of the present results with environmental data taken from the State Offices showed an influence of environmental pollution on the mercury level in wild boar hair.     

Antioxidant enzymes in brackishwater oyster, Saccostrea cucullata as potential biomarkers of polyaromatic hydrocarbon pollution in Hooghly Estuary (India): seasonality and its consequences.

Use of antioxidant enzymes as biomarkers often becomes a complicated process at application level because they show considerable seasonal fluctuation due to both natural and biological factors. In this study, we studied the consequences of seasonal variation of antioxidant enzymes [catalase (EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1), glutathione peroxidase (GPX, EC 1.11.1.9) and microsomal NADPH-DT diaphorase (EC 1.6.99.2)] in the digestive gland of wild brackishwatcr oysters, Saccostrea cucullata for biomonitoring against polyaromatic hydrocarbon (PAH) contamination in Hooghly Estuary, north-eastern coast of India. As a general trend, maximum antioxidant enzyme activities were detected in pre-monsoon period or summer (March-June) followed by a gradual decrease during monsoon (July-October) with a minimum in post-monsoon period or winter (November-February) and this pattern was similar to tissue concentrations of PAHs also. The physiological fluctuations of the antioxidant defense systems were inversely-related to the lipid peroxidation indicating an enhanced susceptibility of oyster tissues to oxidative stress during post-monsoon or winter period. However, the oysters from polluted populations exhibited consistent very high PAHs load in their tissues as well as significant increases in the activities of antioxidant enzymes than in non-polluted populations in all three seasons. The results indicated that the antioxidant enzymes, catalase, SOD and microsomal NADPH-DT diaphorase in digestive gland of S. cucullata could be useful biomarkers of PAHs contamination. It also emphasized that seasonal variation of potential biomarkers like such enzymes should be incorporated into interpretation of biomonitoring studies by the use of appropriate controls and identical treatment in analysis of polluted and non-polluted samples.     

Assessment of metal pollution in Onsan Bay, Korea using Asian periwinkle Littorina brevicula as a biomonitor.

Cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) concentrations in the marine gastropod, Littorina brevicula Philippi, were determined to assess the metal pollution in Onsan Bay, Korea. Samples of L. brevicula employed as a biomonitor and seawater were collected from 12 to 20 stations of Onsan Bay in November 1997, respectively. Dissolved metal concentrations in surface seawater were highest at the station near Onsan Non-ferrous Industrial Complex: 1.15 micrograms l-1 for Cd, 2.49 micrograms l-1 for Pb, 3.75 micrograms l-1 for Cu and 23.98 micrograms l-1 for Zn. These values were 1-2 orders higher than those shown at outer regions of the Bay. Metal concentrations in the soft body of periwinkles were highly variable at different sampling locations: 0.48-27.11 micrograms g-1 for Cd, 1.41-24.91 micrograms g-1 for Pb, 57-664 micrograms g-1 for Cu and 83-246 micrograms g-1 for Zn. The values from stations near the industrial complex were higher than those expected from relationships between body sizes and metal body burdens in periwinkles collected from the whole Korean coast. Spatial distribution of metal concentrations in the periwinkle and seawater indicated that Onsan industrial complex near the Bay is the input source of these metals. Especially, Cd and Pb concentrations in the periwinkle and seawater were distinctly decreased with distance from the Onsan industrial complex. Non-essential metals such as Cd and Pb in the periwinkle showed a strong correlation with dissolved metal concentrations in seawater. Conversely, essential Cu and Zn in the periwinkle were hardly explained by those in seawater, except at the most contaminated sites.     

Seasonal changes in the sensitivity of river microalgae to atrazine and isoproturon along a contamination gradient

A study was undertaken to investigate the environmental impact of herbicides on natural communities of freshwater periphyton and phytoplankton in the river Ozanne and in related nearby water reservoirs, including both pristine and pesticide- (atrazine and isoproturon) contaminated stations. The microalgal toxicity of both herbicides was investigated by short-term studies, using the in vivo fluorescence pattern to perform dose-effect experiments. The taxonomic composition of the communities sampled was assessed by microscopy and by HPLC pigment analysis. The EC50 (periphyton) or EC125 (phytoplankton) values, calculated using in vivo fluorescence endpoints, increased with the herbicide concentration found in the water. In contrast, the structure of the algal communities (periphyton) inhabiting the contaminated stations seemed to be permanently affected when compared to the reference community. A 'memory effect' could be detected, both in herbicide sensitivity and in the structure of periphytic communities that persisted even when peak contaminations had disappeared. This study shows that the response of algal communities is likely to reflect past selection pressures, and suggests that the function and structure of a community could both be modified by the persistent or repeated presence of microcontaminants in natural environments. We could use short-term ecotoxicological tests on freshwater microalgae to assess the effects of past temporary contaminations by agricultural pesticides, and combining this with diversity indices could make it possible to assess the ecotoxicological risk of herbicide contamination even when a complete chemical analysis of the contamination is not feasible.     

Bryophytes as indicators of trace metals pollution in the River Brenta (NE Italy)

The performance of aquatic bryophytes for detecting metal pollution was tested along the River Brenta, in NE Italy. Nine sampling sites were selected, three of them along short tributaries with no anthropic influence upstream, the others along the main bed of the river. Two sites were deliberately placed downstream from a previously known pollution focus. The multivariate analysis (classification and ordination) of the matrix of 10 metals and 38 samples revealed: (i) a good discrimination between 'clean' and potentially polluted sites; (ii) two contamination syndromes, one by As and, to a lesser degree, Pb, and the other by Cr, due to agricultural and industrial activities, respectively; and (iii) the previously known pollution focus was clearly detected. The magnitude of contamination was estimated by means of a comparison between local backgrounds and concentrations of metals measured. The distance of aquatic bryophytes from the center of the river was negatively correlated with metal concentrations, which suggests that this factor should be taken into account in the implementation of sampling protocols.     

Biodiversity of epiphytic lichens and heavy metal contents of Flavoparmelia caperata thalli as indicators of temporal variations of air pollution in the town of Montecatini Terme (central Italy)

The results of a biomonitoring survey carried out in the town of Montecatini Terme (central Italy) in the period 1993-2000 using the biodiversity of epiphytic lichens and the accumulation of heavy metals in thalli of Flavoparmelia caperata as indicators of air pollution are reported. From 1993 to 2000, the mean ILD value for the whole study area increased from 18+/-18 to 42+/-22, the lowest ILD value increased from 0 to 11 and the highest ILD value increased from 67 to 84. A 'lichen desert' was found only in 1993 and stations classified as 'natural' were lacking only in 1993 and 1996. Concentrations of all heavy metals decreased from 1993 to 1999. It is concluded that vehicular traffic is the main source of atmospheric pollution in the study area. The most likely changes that may have caused lichen communities to improve and heavy metals to drop is conversion of heating systems to methane (abatement of SO2) and the use of unleaded gasoline (reduction of Pb). The present results showed that despite their slow growth rate, lichens respond rapidly to decreasing concentrations of air pollutants, allowing annual changes to be detected.     

Potential use of multixenobiotic defense mechanism (MXDM) in Dreissena polymorpha as a biomarker for the monitoring of freshwater pollution

Multixenobiotic defense mechanism (MXDM) has been recently described in marine mussels as potential biomarker for the monitoring of water pollution by organic compounds. In this paper, the measurement of MXDM activity was achieved in a freshwater bivalve. Dreissena polymorpha. Two methods were tested and compared. The first one (MXDM associated ATPase activity) is an indirect method based on the evaluation of the inorganic phosphate production during MXDM activity. The second one (MXDM efflux activity) consists in the measurement of a dye (Rhodamine B) efflux from gill cells in living organisms. Both methods were optimized and evaluated for in situ studies. The results showed a significant induction (4.5 fold) of the MXDM efflux activity after the implantation of organisms for 21 days in a high polluted site. This preliminary study suggests a potential use of the MXDM efflux activity in Dreissena polymorpha as a biomarker for the monitoring of freshwater pollution by organic compounds.     

Binding of Cu(II) to algae in a metal buffer

The interactions of Cu(II) with algal surfaces and exudates were studied in metal-NTA buffers by a combination of several analytical techniques. Suspensions of living algae in the presence of NTA were titrated at constant pH with Cu(II). The various Cu species were determined as follows: a copper ion selective electrode was used reliably in the pCu range 9–12; differential pulse polarography was used to measure separately Cu(II)-NTA complexes and labile Cu(II) species and to evaluate the complexation of copper by ligands in solution; copper bound to the algal surfaces was extracted by acid treatment and measured by AAS. Thus, we determined both the binding of Cu to the algal surfaces and to exudates excreted by the algae. The results were interpreted in terms of conditional equilibrium constants valid at a given pH; the conditional constants, both for the binding to the surfaces and with the exudates increase in the pH range 5.0–6.5. Simple equilibrium models using the experimentally determined binding capacities and equilibrium constants were able to simulate the results and to evaluate the speciation of copper. Under the experimental conditions used, the binding of Cu(II) to algal exudates has a more significant effect on copper speciation than the binding to the algal surfaces. These extracellular ligands may play an important role in decreasing the concentration of free copper ion and thus mitigating the potential toxic effects in organisms.     

Indoor air pollution in a Mexican indigenous community: evaluation of risk reduction program using biomarkers of exposure and effect

Indoor air pollution can be an important risk factor for human health, considering that people spend more than 60% of their time indoors. Fifty percent of the world population and approximately 90% of the rural population in developing countries are using biomass as energy source. Latin America represents 12% of the global consumption of biomass; in Mexico, 27 million people use wood as an energy source. Therefore, in this study we evaluated a 3-stage risk reduction program. The stages were: 1) removal of indoor soot adhered to roofs and internal walls; 2) paving the dirt floors; and 3) introduction of a new wood stove with a metal chimney that expels smoke outdoors. The complete intervention program was applied. In 20 healthy subject residents from an indigenous community in San Luis Potosí, Mexico, we measured blood carboxyhemoglobin (% COHb), DNA damage (comet assay) in nucleated blood cells, and urinary 1-OHP levels before and after the program. Before intervention individuals had a geometric mean COHb level of 4.93% and 53% of the population presented levels above 2.5% considered a safe level. However, in all the studied individuals the levels of COHb were reduced to below 2.5% (mean level 1.0%) one month after the intervention. Moreover, when compared, DNA damage in people exposed before the intervention was higher (5.8+/-1.3 of Tail Moment) than when the program was introduced (2.8+/-0.9 of Tail Moment) (P>0.05) and a same trend was observed with urinary 1-OHP levels; 6.71+/-3.58 micromol/mol creatinine was the concentration before intervention; whereas, 4.80+/-3.29 micromol/mol creatinine was the one after the program. The results suggest that the intervention program offers an acceptable risk reduction to those families that use biomass for food cooking.