Trace metals assessment in water, sediment, mussel and seagrass species--validation of the use of Posidonia oceanica as a metal biomonitor

The accumulation of trace metals (Cd, Co, Cr, Hg, Ni and Pb) was measured in water, sediment, the mussel Mytilus galloprovincialis and the seagrass Posidonia oceanica. Samples were collected in three locations of the north-western Mediterranean (Canari, Livorno and Porto-Torres) which present different levels and sources of human impact. Analyses in the different compartments (water, sediment, M. galloprovincialis and P. oceanica) have allowed to identify Canari as the most Cd, Co, Cr and Ni contaminated site; Livorno as the most Hg contaminated and Porto-Torres as the most Pb contaminated. Furthermore, for the first time, metal concentrations found in P. oceanica have been compared with those found in the water column, in the sediment and in the recognized metal bio-indicator species M. galloprovincialis and the results obtained have led to the same conclusions. Thus, this study allows to validate the use of P. oceanica as metal biomonitor of coastal waters.     

Evaluation of the variegated scallop Chlamys varia as a biomonitor of temporal trends of Cd, Cu, and Zn in the field

This study assesses the potential of the scallop Chlamys varia as a biomonitor of metal contamination in the field. Cd, Cu, and Zn concentrations were determined in the soft tissues and organs of individuals from the French Atlantic coast sampled over a 1 year period and covering a wide range of size. All metals were selectively distributed among the different body compartments considered, and their concentrations were influenced by the size of the specimens or the sampling-season. The present work shows the importance of considering the body compartment, the sampling period and the size in studies aiming at using this scallop as a biomonitor species. Among tissues, the digestive gland and kidneys exhibited the highest metal concentrations whatever the season or the size. The digestive gland contained 65 and 48% of the whole Cd and Cu body burdens, respectively, and kidneys accounted for 85% of the Zn load. Those tissues are therefore particularly recommended for use in biomonitoring programs.     

The amphipod Hyalella azteca as a biomonitor in field deployment studies for metal mining

Specimens of the amphipod Hyalella azteca were deployed, in June-July 2003, along metal contamination gradients in two rivers affected by metal mining in the Abitibi - James Bay region, northwestern Québec. The amphipods were placed along with natural food items in small, acrylic cages and left in six riverine sites for 17 days. Twelve metals (As, Cu, La, Mn, Ni, Sb, Se, Tl, U, V, Zn, and CrO₄²⁻ modelled by WHAM VI) in transplanted H. azteca varied along metal contamination gradients in a consistent manner, i.e., as a function of metal exposure. Bioaccumulation of As, Cr, La, Ni, Sb, Se, Tl, U and V, as defined by a field BCF, was significantly correlated with their chronic toxicity potential towards the amphipod. We conclude that H. azteca may be a useful field biomonitor for metal mining. In addition, our results suggest that such biomonitoring programs should include less studied elements such as Se in mining effluents.     

Bioaccumulation behaviour of transplants of the lichen Flavoparmelia caperata in relation to total deposition at a polluted location in Portugal

This experiment compares the short and long time element accumulation behaviour of transplants of Flavoparmelia caperata lichen thalli and total deposition in an atmospheric polluted area. It was found that lichens exposed for a short time behaved differently from lichens in cumulative exposition suggesting the presence of acclimatization behaviour. The lichen transplant elemental content does not unequivocally represent the average or cumulative environmental availability of the exposure period. Reflection characteristics depend on the element and the lichen physiological conditions. Good correlations between lichen elemental contents and total deposition were obtained when a physiological lichen parameter was introduced in a mathematical model, suggesting that metabolically mediated accumulation is important.     

Atmospheric quality and distribution of heavy metals in Argentina employing Tillandsia capillaris as a biomonitor

The atmospheric quality and distribution of heavy metals were evaluated throughout a wide region of Argentina. In addition, the biomonitor performance of Tillandsia capillaris Ruiz & Pav. f. capillaris was studied in relation to the accumulation of heavy metals and to its physiologic response to air pollutants. A sampling area of 50,000 km2 was selected in the central region of the Argentine Republic. This area was subdivided into grids of 25 x 25 km. Pools of T. capillaris, where present, were collected at each intersection point. From each pool three sub-samples were analyzed independently. Furthermore, five replicates were collected at 20% of the points in order to analyze the variability within the site. The content of Co, Cu, Fe, Ni, Mn, Pb and Zn was determined by Atomic Absorption Spectrometry. Chemical-physiological parameters were also determined to detect symptoms of foliar damage. Chlorophylls, phaeophytins, hydroperoxy conjugated dienes, malondialdehyde and sulfur were quantified in T. capillaris. Some of these parameters were used to calculate a foliar damage index. Data sets were evaluated by one-way ANOVA, correlation analysis, principal component analysis and mapping. Geographical distribution patterns were obtained for the different metals reflecting the contribution of natural and anthropogenic emission sources. According to our results it can be inferred that Fe, Mn and Co probably originated in the soil. For Pb, the highest values were found in the mountainous area, which can be attributed to the presence of Pb in the granitic rocks. Ni showed mainly an anthropogenic origin, with higher values found in places next to industrial centers. For Zn the highest values were in areas of agricultural development. The same was observed for Cu, whose presence could be related to the employment of pesticides. The foliar damage index distribution map showed that the central and southeastern zones were the ones where the major damage in the bioindicator was found. The central zone coincides with the city of Córdoba whereas the southeastern area is strictly agricultural, so the high values found there could be related to the use of pesticides.     

Willow ptarmigan (Lagopus lagopus) as a biomonitor of environmental metal levels in Norway

The purpose of this study was to examine the potential of a native wild bird, Lagopus lagopus, as a monitor of environmental metal levels, in particular with respect to the influence of atmospheric deposition of metals from long-range transport. Specimens of willow ptarmigan were collected from ten different locations in Norway. The concentrations of cadmium, zinc and copper were determined in kidneys of birds from all sites. Mean cadmium levels in adult ptarmigan kidney ranged from 6.6 to 48.5 microg g(-1) (wet weight), with individual concentrations up to 71.0 microg g(-1). These are among the highest cadmium levels reported in wild birds. The kidneys of adult birds contained 3-10 times higher cadmium levels than kidneys from juvenile birds in the same collection area, and most of the high cadmium levels probably reflect natural exposure, rather than atmospheric pollution. Concentrations of elements in kidney tissues were highly correlated with each other.     

Biomonitoring using the lichen Hypogymnia physodes and bark samples near Zlatna, Romania immediately following closure of a copper ore-processing plant

Lichen transplants were established along a 40km transect centred on a large mine waste dump close to Zlatna town centre, two weeks after closure of a major industrial source, to compare spatial patterns of element concentrations in lichen and bark samples. After 3 months of exposure, spatial patterns of 4 element concentrations (Pb, Cu, Zn and Fe) in transplants confirmed deposition due to a point source 'Zlatna influence'. Cu and Pb reached concentrations 8 and 4 times, respectively, higher than samples transplanted in the 'background' site, and over 200 (Cu) and 2000 (Pb) times higher relative to 'background' bark. Ten out of 15 elements analysed reached highest concentrations in bark. Spatial patterns confirmed long-term pollution for 6 elements (Pb, S, Fe, Cu, Zn and Ba). The study provides a model baseline to monitor recovery following closure of major industrial sources and highlights the importance of considering biogeochemical processes when interpreting metal concentrations.     

Use of the aquatic lichen Dermatocarpon luridum as bioindicator of copper pollution: accumulation and cellular distribution tests

Laboratory experiments were conducted to investigate the potential use of the aquatic lichen Dermatocarpon luridum as bioindicator of copper pollution. Lichen thalli were exposed to 0.00, 0.25, 0.50, 0.75 and 1.00 mM copper in synthetic freshwater to solve the problems of metal bioavailability. The mineral composition of this media was prepared so that it corresponded to the ion composition of natural waters in D. luridum ecosystems. Sequential elution procedures using NiCl2 or Na2-EDTA (20 mM) were used to determine the distribution of metals at different cellular sites. The copper concentration extracted from thalli was correlated with pollution intensity, the greater correlation being with the Na2-EDTA extractant. The malondialdehyde concentration in thalli can be used as indicator of copper pollution; however, similar membrane degradation was observed for 0.25 and 0.50 mM copper and for 0.75 and 1.00 mM copper.     

Effects of site-specific climatic conditions on the radial growth of the lichen biomonitor <Emphasis Type="Italic">Xanthoria parietina</Emphasis>

The protocols commonly applied in surveys with lichens as biomonitors of airborne trace elements require analyses of samples derived from thalli or parts of thalli grown in the last year before sampling, under the postulation that samples of the same size are of the same age. Unfortunately, the influence of ecological site-specific factors on lichen growth is still largely ignored, so that samples of the same size collected in environmentally and climatically diverse sites might actually differ in age. This work aims at quantifying the influence of climatic conditions on the radial growth rates (RaGRs) of Xanthoria parietina, one of the most popular lichen biomonitors. RaGR was monitored in seven populations distributed along an altitudinal transect of 30 km in the Classical Karst (NE Italy), from 20 to 500 m above sea level. For c. 17 months, lobe growth was measured seasonally with a digital calliper, and site-specific climatic variables were monitored by means of thermo-hygrometric sensors and implemented by meteorological data. Finally, the lobe growth of X. parietina was modelled as a function of 18 environmental variables. Results revealed that thalli of relatively dry sites had significantly lower seasonal RaGR with respect to moister ones. Considering that cumulative precipitations were equally distributed along the transect, it was concluded that RaGR of X. parietina is affected negatively by high air temperatures and positively by high relative humidity. The importance of RaGR variation in lichen bioaccumulation studies is critically discussed.     

An Air Quality Study in the Vicinity of Lewiston,Idaho, and Clarkston,Washington

This report summarizes data and conclusions from a one-year, interstate air quality study conducted in 1962 in the vicinity of Lewiston, Idaho, and Clarkston, Wash.^{1, 6, 7} The sampling and analyses techniques were selected to permit differentiation between possible sources and types of air pollutants.     

Exposure to polychlorinated biphenyls in residents near a chemical factory in Italy: the food chain as main source of contamination

High levels of PCBs were recently found in soil, food and some farmers living close to a chemical factory which until the 1980s had produced polychlorinated biphenyls (PCBs) in Brescia, North Italy. We performed a survey on a random sample of subjects aged 20-79 years living in various areas of the town with different levels of soil pollution to investigate factors associated with increased levels of PCB in serum (24 congeners were tested). Total PCB values were closely related to age (Spearman r=0.68; p<0.0001). The 166 consumers of locally produced food had higher PCB levels than non-consumers (median=1143 versus 719; 95th centile=9301 versus 2635ng/g lipid) with the highest levels among consumers of food produced in the most contaminated area close to the factory (median=2551; 95th centile=33464ng/g lipid). A dose-effect relationship between consumption of food produced in this area and PCB blood levels was observed (Spearman r=0.52, p=0.0014). Consumers of only plant food produced in this area had higher levels of PCB than non-consumers (median=1100; 95th centile=10,800ng/g lipid). Three subjects who had worked at the factory in the past showed high PCB levels. Distribution of PCB congeners did not differ between consumers of locally produced food and non-consumers, apart from PCB 209 which was found at high levels in former factory workers and was more common among consumers of food produced in the polluted area. In conclusion, we found high serum PCB levels in humans living in a highly polluted area in an industrialized town in Italy, due mainly to consumption of food produced in polluted areas.     

Historical and current atmospheric deposition to the epilithic lichen Xanthoparmelia in Maricopa County,Arizona

Spatial patterns of atmospheric deposition of trace elements to an epilithic lichen were assessed using a spatial grid of 28 field sites in 1998 throughout Maricopa County, Arizona, USA. In addition, samples of Xanthoparmelia spp. from Arizona State University lichen herbarium material (1975-1976) was utilized for a limited number of sites in order to explore temporal trends. The lichen material was cleaned, wet digested and analyzed by ICP-MS for a suite of elemental concentrations [antimony (Sb), cadmium (Cd), cerium (Ce), chromium (Cr), cobalt (Co), copper (Cu), dysprosium (Dy), europium (Eu), gadolinium (Gd), gold (Au), holmium (Ho), lead (Pb), lutetium (Lu), neodymium (Nd), nickel (Ni), palladium (Pd), platinum (Pt), praseodymium (Pr), samarium (Sm), scandium (Sc), silver (Ag), terbium (Tb), thulium (Tm), tin (Sn), uranium (U), ytterbium (Yb), yttrium (Y), and zinc (Zn)]. Cluster analysis and principal component analysis suggest three major factors, which, depending on regional aerosol fractionation, explain most of the variation in elemental signatures: (1) a group of widely distributed rare earth elements (2) a highly homogenous Co, Cr, Ni, and Sc component representing the influence of mafic rocks, and (3) anthropogenic emissions. Elemental concentrations in Maricopa County lichens were generally comparable to those reported for relatively unpolluted areas. Only highly urbanized regions, such as the greater Phoenix Metropolitan Area and the NW corner of the county, exhibited elevated concentrations for Zn, Cu, Pb, and Cd. Lead levels in lichens have fallen over the last 30 years by 71%, while Zn concentrations for some regions have increased by as much as 245%. From the spatial pattern of elemental deposition for Cd, Cu, Ni, Pr, Pb, and Cu, we infer that agriculture, mining, industrial activities, and traffic probably are the major air pollutant sources in Maricopa County.     

Use of a lux-marked rhizobacterium as a biosensor to assess changes in rhizosphere C flow due to pollutant stress

The flow of carbon from plant roots into soil supports a range of microbial processes and is therefore critical to ecosystem function and health. Pollution-induced stress, which influences rhizosphere C flow is of considerable potential importance, and therefore needs to be evaluated. This paper reports on a method, based on reporter gene technology, for quantifying pollutant effects on rhizosphere C flow. The method uses the lux-marked rhizobacterium Pseudomonas fluorescens, where bioluminescence output of this biosensor is directly correlated with the metabolic activity and reports on C flow in root exudate. Plantago lanceolata was treated with paraquat (representing a model pollutant stress) in a simple microcosm system. The lux-biosensor response correlated closely with C concentrations in the exudate and demonstrated that the pollutant stress increased the C flow from the plantago roots, 24 h after application of the herbicide. The lux-reporter system therefore potentially offers a technique for use in assessing the impact of pollutant stress on rhizosphere C flow through the soil microbial biomass.     

Comparison between the accumulation capacity of four lichen species transplanted to a urban site

The capacity to accumulate trace elements from the atmosphere of the lichens Hypogymnia physodes, Parmelia sulcata, Pseudevernia furfuracea and Usnea gr. hirta transplanted to an urban site of N Italy was compared. Twenty-nine elements (Al, As, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hg, I, K, La, Mg, Mn, Ni, Pb, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Zn) were analyzed by Instrumental Neutron Activation Analysis (INAA) and Electro-Thermal Atomic Absorption Spectroscopy (ET-AAS). The ratio between the concentrations of each element in exposed samples to that of control samples (exposed-to-control ratio and EC ratio) was used to investigate the accumulation rates of lichen thalli. The results showed that in general elements did not exhibit well defined trends, but rather showed fluctuations, and indicated that H. physodes, P. furfuracea and U. gr. hirta have a similar accumulation capacity, while that of P. sulcata is lower.     

Feasibility of phosphate fertilizer to immobilize cadmium in a field

To reduce effectively cadmium (Cd) phytoextractability by phosphate fertilizer in Cd contaminated soil, fused and superphosphate (FSP) was applied at the rate of 0, 33.5 (recommendation level), 167.5, and 335 kg P ha⁻¹ for radish (Raphanus sativa L.). Unlike from what we expected, soil Cd extractability and Cd concentration in radish increased with increasing FSP application in the field. To determine the effect of FSP on Cd immobilization, FSP was mixed with the selected soil at the rate of 0, 200, 400, 800, and 1600 mg P kg⁻¹ and then incubated for 8 weeks. As observed in the field study, NH₄OAc extractable Cd concentration increased slightly with FSP addition up to 400 mg P kg⁻¹ and thereafter dramatically decreased upon increasing its application rate. Soil pH and negative charge were decreased at low level of FSP application up to 400 mg P kg⁻¹, but thereafter continually increased with increasing application level. This could be indirect evidence that net soil negative charge was increased by the specific adsorption of phosphate at the high rate of FSP application over 400 mg P kg⁻¹. The labile Cd fraction (water soluble and exchangeable + acidic fraction) increased with increasing FSP application by 400 mg P kg⁻¹ and thereafter gradually decreased with corresponding increase in unlabile fraction (oxidizable and residual fraction). Based on these results, FSP might be applied with a very high rate over 800 mg P kg⁻¹ to decrease Cd extractability in the selected field. However, this level is equivalent to 1440 kg P ha⁻¹, which is about 43 times higher than the recommendation levels for radish production and resulted in a significant increase in water soluble P concentration creating a new environmental problem. Therefore, the feasibility of FSP to reduce Cd extractability in the field is very low.     

In situ bioassays with Chironomus riparius larvae to biomonitor metal pollution in rivers and to evaluate the efficiency of restoration measures in mine areas

In this study we evaluate the ability of an in situ bioassay with Chironomus riparius larvae, using larval development and growth as endpoints, to biomonitor water quality and to assess the biological recovery of metal contaminated freshwater ecosystems of mine areas that are subject of restoration measures. The bioassay was carried out in streams located near an abandoned goldmine in North Portugal, throughout an environmental rehabilitation of the mine (2002-2004). During this period, a decrease in the inhibition of larval growth in the metal contaminated stream was observed. The bioassay was also performed in streams located near an active tungsten mine in Central Portugal. Larval growth and development were highly inhibited in the stream that receives acid drainage from the tungsten mine and treated water from the AMD treatment station. The results indicate that the bioassay can be used to evaluate the efficiency of environmental restoration measures in mining areas.     

The presence of a river bird, the dipper, in relation to water quality and biotic indices in central Italy

A good water quality bio-indicator should be sensitive to different forms of water degradation in any geographical area, and effectively track water quality changes in time. We investigated whether the presence of a bird, the dipper (Cinclus cinclus), in 47 reaches of 35 streams of central Italy was affected by stream pollution as assessed by the Extended Biotic Index. Data from the literature and interviews with ornithologists furnished information about past dipper presence and water quality in the study streams. In 93.3% of cases dippers occurred in unpolluted reaches. The dipper was absent from 93.7% of polluted or strongly polluted streams. Dippers disappeared from 50% of the study streams for which past information was available. In a few streams dippers disappeared after the quality of water had degraded. Water quality degradation in the study area, especially in the hill streams, is causing dipper areale to contract to higher altitudes. Dipper is a good water quality bio-indicator for Mediterranean streams.     

Pb isotopes as tracers of mining-related Pb in lichens, seaweed and mussels near a former Pb-Zn mine in West Greenland

Identification of mining-related contaminants is important in order to assess the spreading of contaminants from mining as well as for site remediation purposes. This study focuses on lead (Pb) contamination in biota near the abandoned ‘Black Angel Mine’ in West Greenland in the period 1988-2008. Stable Pb isotope ratios and total Pb concentrations were determined in lichens, seaweed and mussels as well as in marine sediments. The results show that natural background Pb (²⁰⁷Pb/²⁰⁶Pb: 0.704-0.767) and Pb originating from the mine ore (²⁰⁷Pb/²⁰⁶Pb: 0.955) have distinct isotopic fingerprints. Total Pb in lichens, seaweed, and mussels was measured at values up to 633, 19 and 1536 mg kg⁻¹ dry weight, respectively, and is shown to be a mixture of natural Pb and ore-Pb. This enables quantification of mining-related Pb and shows that application of Pb isotope data is a valuable tool for monitoring mining pollution.     

The performance of three cultivars of rice grown near to, and distant from, a fertiliser plant

The effects of three cultivars, two water regimes and two rates of applying nitrogen fertilisers were tested when studying the performance of rice (Oryza sativa L.) near to, and distant from, a fertiliser plant emitting atmospherically dispersed pollutants. The atmosphere near the fertiliser plant had average daily peak concentrations of 144 and 210 microg m(-3) of SO(2) and NO(2), respectively. Growth was less near to, than at a distance from, the fertiliser plant. On average it was decreased by water stress while the effects of different amounts of nitrogen fertiliser were variable. Whilst there were a number of interactions involving nitrogen and water treatments, the most consistent were associated with the responses of the three cultivars at the two locations. The three cultivars performed similarly at the unpolluted control site, but there were major differences at the polluted site. These were most clearly exemplified by changes in the proportion of dry matter allocated to yields of grain and straw. At the unpolluted site, grain accounted for about 30% of the combined yields of grain and straw. At the polluted site, grain accounted for 1, 23 and 31% of the combined grain and straw yields of cultivars CO 43 (the most sensitive), TKM 9 and GR 3 (the most tolerant). Grain yields were closely related to numbers of filled grains per plant. At the polluted site, 98% of grains failed to develop in CO 43, whereas in GR 3, the number of panicles, and therefore the potential number of grains, was significantly enhanced.