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Among the heavy metals (HMs) whose concentrations in natural environments have risen considerably in the last era, chromium (Cr) is one of the most toxic. Because of the risks it poses to human and environmental health, it is of great importance to screen the variation in Cr contamination in the atmosphere and decrease the pollution. This study aimed to determine the proper tree species that can be used to monitor and reduce Cr contamination. For this aim, studies were conducted on Tilia tomentosa, Robinia pseudoacacia, Cedrus atlantica, Pseudotsuga menziesii, and Fraxinus excelsior species growing in Düzce, which is among the 5 most contaminated European towns according to the World Air Pollution report. Samples taken from these trees were examined, and changes in Cr concentration depending on species, organs, compass direction, and age range in the last 60 years were evaluated. Results indicated higher Cr pollution in recent years, consistent with higher traffic density, but that there was no consistent effect of compass direction. It was also determined that the tree species most appropriate for screening the variation in Cr contamination in the airborne were Tilia tomentosa, and the most appropriate species for decreasing pollution were Robinia pseudoacacia and Cedrus atlantica.

Heavy metals (HMs) are natural components of the Earth's crust that might originate from natural and anthropogenic sources. In excess quantities, the presence of these metals is harmful for both environment and human health. Taking this into account, various investigators examined bioaccumulator species in order to reduce environmental toxicity, among these Baccharis trimera. Therefore, the present study aimed to determine the capacity of B. trimera to bioaccumulate HMs and assess consequent cytogenotoxicity following exposure. B. trimera vegetative parts were collected from two groups (1) control, in which plants were cultivated in soil exposed to distilled water, and (2) exposed, in which plants were cultivated in soil exposed to HMs including manganese (Mn), iron (Fe), lead (Pb), copper (Cu), cobalt (Co), zinc (Zn), and chromium (Cr). HMs were quantified in cultivation soil and extracts (aqueous and ethanolic) as well as infusion of B. trimera vegetative parts. Root lengths and cytogenotoxic effects were determined using Allium cepa test. Results demonstrated that all HMs studied were absorbed and bioaccumulated by B. trimera. Root lengths were decreased when exposed to ethanolic extract of B. trimera cultivated in soil exposed to HMs solution, which was the extract that exhibited the highest cytogenotoxicity values. Thus, data demonstrated that B. trimera might serve as a bioaccumulator for the reduction of environmental toxicity associated with the presence of certain HMs. [ABSTRACT FROM AUTHOR]

This study investigates how strontium (Sr) ions act on meristematic root tip cells of lentil (Lens culinaris) with changing parameters (time and concentration). Plant seeds were exposed to both a standard solution of Sr for different lengths of time (1/4, 1/2, 1, 2, 4, 8, 12, 16, 20 and 24 hours) at a fixed concentration of 1.0 molL-1 (M) and Sr ions at various concentrations (0.05, 0.1, 0.25, 0.5 and 1.0 M) for a certain length of time (12 hours). The seeds treated with Sr were made to sprout and microscopic examination focused on the root tips. The aim of microscopic examination was to clarify chromosomal abnormalities of cell division. Microscopic examination showed that various abnormalities occurred in cells of the seedlings, abnormalities such as chromosome adherence, chromosome breakings, bridge chromosomes, chromosome dispersion, chromosome shrinking, fish bones and ring chromosomes. Those abnormalities were detected several times for each treatment depending on the different periods and concentrations. Adsorption and absorption of Sr inside lentil seeds were detected by the spectroscopic method. Removed and excess amounts of Sr ions were found by spectroscopic determination. Statistical evaluation of the results was used in order to reveal the differences and similarities. The results showed that while there is a positive correlation with the concentration parameter, there is a negative correlation with the time parameter. Over 90% of Sr was removed from the solution during 12-hour exposure. Lentil seeds can be accepted as good bioaccumulators of Sr ions only for an exposure period shorter than 12 hours at an Sr concentration of 1 M.

The amounts of certain heavy metals in waterfowl fluctuate depending on a number of factors. The use of feathers in heavy metal contamination studies is gaining popularity for several reasons, including the lack of need for deep freezing for sample preservation, the fact that it is a non-destructive, non-invasive method that does not require killing an individual, and the ability to predict lead and cadmium concentrations in internal tissues. A total of 22 publications from eight Asian countries including Pakistan, China, Hong Kong, India, Iran, South Korea, Indonesia, and Japan were identified and analysed in this study. The highest number of study sites were found from Pakistan (n = 12), followed by China (n = 9), Hong Kong, South Korea, and India (n = 7) each. A total of 10 heavy metals, viz cadmium, chromium, lead, copper, nickel, zinc, iron, mercury, selenium, and arsenic, have been identified for the review. Mercury (0.17–79.66 ppm) has been studied in all 44 species, whereas selenium (0.98–4.88 ppm) has only been studied in five species. Mercury (8.6 ppm) contamination is highest in Painted Stork from India. Cadmium, lead, copper, and arsenic contamination was detected in the highest concentrations in Cattle Egret and Indian Pond Heron. The highest contamination of cadmium (41.1 ppm), lead (296 ppm), and arsenic (20 ppm) were found in Cattle Egret from Pakistan. Chromium, nickel, and zinc contamination was highest in waders such as Marsh Sandpiper (114.7 ppm), Little Ringed Plover (114.8 ppm), and Little Stint (328.4 ppm), respectively from India. Black-tailed Gull from South Korea had the highest contamination of Iron (4055.55 ppm) and selenium (7.55 ppm). Feather analysis is not an alternative of internal tissue analysis. It should be considered as an initial warning of the hazardous effects of the heavy metals in the waterbirds. [ABSTRACT FROM AUTHOR]

Soil pollution by heavy metals from industrial and anthropogenic activities is prevalent and a serious threat to ecosystems and humans. To immobilize heavy metal toxicity using trees is an effective and low-cost method for soil remediation. The present study was aimed to assess the most suitable bioindicator of trace elements including copper (Cu), cadmium (Cd), and lead (Pb) among Morus alba and Eucalyptus camaldulensis plant species at seven different sites in Faisalabad, an industrial city of Pakistan during the summer and winter seasons. Samples from the leaf, bark, deposited dust, and soil of both subjected species was collected for the assessment of metals accumulation. The recorded data showed that the trend of heavy metal concentration in soil, deposited dust, bark, and the leaf of both species was Pb > Cu > Cd. Generally, the maximum concentration of Cd, Cu, and Pb was recorded at the building material processing area during both seasons in both subjected species. Moreover, the highest concentration of Cd and Pb was recorded in leaf samples, while the highest concentration of Cu was recorded in dust samples. These results suggesting the idea that tree leaves can be used as a good indicator of Cd, and Pb concentration. In the case of Cu, a highly significant correlation (P < 0.05) was found between Cu concentration in deposited dust and leaves of both species during both growing seasons, indicating that the main source of Cu accumulation is atmospheric dust. Moreover, the summer season was more sensitive for the exposure of Cd, Cu, and Pb while, M. alba was proved as a good bioindicator and bioaccumulator for all recorded heavy metals during both seasons. According to the obtained results, M. alba trees are more likely to capture Cd, Cu, and Pb from the air, so planting these trees in industrial areas with such atmosphere pollutants would be beneficial. [ABSTRACT FROM AUTHOR]

Household, industrial, office and various other human activities produce waste. Based on the type, waste consists of liquid, solid, gas and B3. Each waste management needs to be carried out sustainable so that it will not damage the environment and human health. This paper aims to find out the effectiveness of plants in aquatic waste management. The method used in this research is literature study in the form of research articles that have been published in related fields. The data found will be analyzed descriptively qualitatively and determine the type of plant that is effective in aquatic waste management and the way plants in degrade hazardous substances that are in the waste. The results of the literature study show that some plants have a special mechanism in reducing hazardous substances contained in waste both actively and passively. [ABSTRACT FROM AUTHOR]

Fluoride (F) is considered one of the most phytotoxic pollutants, even when present in low concentrations. When dispersed in the air, F can be transported to about 100 km from the polluting source, reaching plants, animals and humans and causing serious damage. Nevertheless, studies are still scarce on the effect of fluoride in Cerrado species integrating morphological, anatomical and physiological responses. Therefore, this study aimed to investigate the effect of simulated rainfall containing potassium fluoride (KF) on Hancornia speciosa leaves and roots, to determine its bioaccumulator potential. Young plants at approximately 45 days of emergence were treated daily with simulated KF rain at four concentrations (0, 4, 8 and 12 mg L−1), and four replicates. The experiment was carried out for 40 days, in completely randomized design. After KF exposure, visual, morphological and chlorophyll a fluorescence analyses were performed, alongside fluoride accumulation assessments in roots and shoots. Hancornia speciosa did not present any visual, anatomical and physiological symptoms in response to fluoride; however, it showed an accumulation of phenolic compounds in mesophyll root and leaf cells in all treatments. Physiological characteristic preservation and fluoride accumulation in roots and leaves allow us to suggest that Hancornia speciosa displays tolerance potential at the investigated doses. [ABSTRACT FROM AUTHOR]

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In this study, we were interested in evaluating the impact of a mixture of two neonicotinoid insecticides and their effects on a bioaccumulative organism and bioindicator of environmental pollution, the snail Helix aspersa. This is a subchronic toxicity study (21-day). Insecticide toxicity is determined in the snail Helix aspersa by a laboratory biotest on animals exposed to increasing concentrations of insecticide mixture (70 µg/g, 180 µg/g, 340 µg/g diet). Our results show physiological disturbances in the weight and shell diameter of the treated snails, while metabolic changes indicate a disturbance in protein levels and a decrease in carbohydrate levels (dependent dose) in the hepatopancreas and kidney. Our results also show the existence of an induction of catalase activity constituting one of the cellular defence mechanisms against the presence of insecticides in two target organs. [ABSTRACT FROM AUTHOR]

The motorized vehicle activities could result air pollution. One of the pollutan emitted from fuel process is lead which might be reduced by using Bogenvil plants (Bougainvillea spectabilis Wild). Bogenvil were planted in a 1 x 1,5 meter square sized green house where there is a particular hole to flow exhaust fume of motorized vehicle for an hour in each 3, 6, 9 and 12 day after the first exposure. The result shows that Bogenvil leaves have ability to absorb Pb metal emitted from vehicle in response to the exposure time. The highest accumulation of Pb in the leave is 0,469 mg/Kg with exposure time of 12 days. For this reason, the Bogenvil plant can be used as bio- accumulator of timbale metal in the air.

Environmental pollution of aquatic ecosystems leads to an interference in several fundamental biochemical and physiological functions. In this study the interference of Cd and Pb pollutions on the physiological growth and subsequently on the age determination was investigated. The hermit crab, Coenobita scaevola (C.s) was selected as a bioaccumulator in this study. The direct and indirect age determination methods were carried out using annual band counts and carapace length, respectively. The results showed that, there was very low correlation (R2 < 0.5) between direct and indirect age determination. Wavelet Neural Network (WNN) was applied to take into account the environmental effects such as the accumulation of Cd and Pb elements in the C.s’ tissues. It was observed that WNN successfully enhanced the growth rate model and estimated the C.s’ age (R2 > 0.95). In addition, it was concluded that the environmental pollution had interaction with the growth physiology such as weight and length. [ABSTRACT FROM AUTHOR]

Until recently, there have been only few published reports concerning the use of mangrove macroalgae as biomonitors to assess the estuarine metal contamination. Therefore, the present study was an effort to investigate the biomonitoring of metal contamination using mangrove macroalgae in the tropical Miri estuary of Sarawak, Malaysia. The metal concentrations (Cu, Fe, Mn, and Zn) were determined in the surface sediments, estuarine water, and six dominant macroalgae species that epiphytically grow on mangrove pneumatophores. The results showed that the scheme of metal occurrences in estuarine surface water and sediments was Fe > Mn > Zn > Cu and Fe > Zn > Mn > Cu, respectively. Among the studied metals in algal tissues, irrespective of macroalgal species, the concentration of Fe was found to be the highest. Significant positive correlations were found between Cu and Zn in all macroalgal species (except Caloglossa ogasawaraensis and Dictyota sp.), indicating the common origin of those elements. Concentrations of each of the studied metal in algal tissues varied among macroalgal species, probably because of the differences of structure, age, and growth of thallus among macroalgal species. To our knowledge, this is the first comprehensive report describing the biomonitoring of metal contamination using macroalgae from Malaysian mangrove systems. [ABSTRACT FROM AUTHOR]

Tilia spp. (lime trees) as ornamental trees have a privileged place in the European mythology and traditions and this is a reason of their constant presence in the urban landscape. Lime trees are in general very resistant to biotic and abiotic stress, although some sanitary problems may occur (e.g. aphids and other related organisms). Tilia spp. are considered a good bioindicator and accumulator of heavy metals. Seasonal accumulations of Pb, Ni, Cr, Mn, Cu and Fe in leaves of Tilia spp. in urban and periurban green areas of Western Romania, under different traffic conditions, were analyzed using atomic absorption spectrophotometry. The results confirmed the direct correlation between the traffic intensity and the accumulation of Pb in leaves. By mitigating the effects of air pollution, especially in terms of heavy metals, Tilia spp. should be further promoted as urban trees. [ABSTRACT FROM AUTHOR]

The study area located in the western part of the Eastern Pontides, NE Turkey, represents the eastern part of the metallogenic province of the Black Sea region. The soil, water, and some mosses from the area contain heavy metal pollution from the mines and tailings of the abandoned and partially active massive sulfide deposits and their host rocks. The surface/subsurface/underground ore bodies generally cause the acidification of groundwater and the enrichment of heavy and toxic trace metals (Cu, Zn, Cd, Fe, As, and Pb) in the water, soil, and mosses. The mosses are Rhabdoweisia crispata, Pohlia nutans, and Pohlia elongata. R. crispata is a newly reported plant in Turkey, and the abovementioned moss species are observed especially where the toxic element contents of the water and soil are enriched. The mosses are sensitive to the trace metals and thus accumulate metal ions, predominantly Fe, Al, and Mn, which are apparent in the interaction between the water and roots. R. crispata is a better accumulator of trace metals and some major elements than the other mosses. R. crispata is therefore suitable for use in the recovery of polluted soil and water affected by acid mine wastewater from active and/or abandoned mining sites in the NE of Turkey. [ABSTRACT FROM AUTHOR]

The possibility of using freshwater Ulva (Chlorophyta) as a bioaccumulator of metals (Co, Cr, Cu, Mn and Zn) in lake and river water was examined weekly in the summer of 2010 in three types of samples: the water, the sediment and the thalli of Ulva. Samples of freshwater Ulva were collected from two aqueous ecosystems lie 250 km away from the basin of the Baltic Sea and 53 km from each other. A flow lake located in the centre of the big city was the first water reservoir (ten sites) and second, the suburban river (six sites). The mean metal concentrations in the Ulva tissue from the river and the lake decreased in the following order: Mn > Zn > Cr > Cu > Co and Mn > Cr > Zn > Cu > Co, respectively. Moreover, a negative and statistically significant correlation between Mn concentrations in the Ulva thalli and the river water was observed. Additionally, numerous correlations were noted between the different concentrations of metals within the Ulva thalli, in the water and in the sediment. The great concentrations of Mn and Zn and the smallest of Co were found in thalli of Ulva, irrespective of the type of the ecosystem from which samples of algal thalli originated. Freshwater Ulva populations examined in this study were clearly characterized a dozen or so times by the higher Mn and Cr accumulation than taxa from that genera coming from sea ecosystems. The calculated bioconcentration factor confirm the high potential for freshwater Ulva to be a bioaccumulator of trace metals in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: We analyzed the ability of freshwater taxa of the genus Ulva (Ulvaceae, Chlorophyta) to serve as bioindicators of metal in lakes and rivers. Changes in heavy metal (Ni, Cd and Pb) and alkaline earth metal (Ca and Mg) concentrations in freshwater Ulva thalli were investigated during the period from June to August 2010. The study was conducted in two ecosystems in Western Poland, the Malta lake (10 sites) and the Nielba river (six sites). Three components were collected for each sample, including water, sediment and Ulva thalli. The average concentrations of metals in the water sample and in the macroalgae decreased in the following order: Ca>Mg>Ni>Pb>Cd. The sediment revealed a slightly altered order: Ca>Mg>Pb>Ni>Cd. Ca and Mg were found at the highest concentrations in thalli due to the presence of carbonate on its surface. Among the examined heavy metals in thalli, Ni was in the highest concentration, and Cd found in the lowest concentration. There were statistically significant correlations between the levels of metals in macroalgae, water and sediment. Freshwater populations of Ulva exhibited a greater efficiency to bioaccumulate nickel as compared to species derived from marine ecosystems. [Copyright &y& Elsevier]

Abstract: The tunicate Pyura chilensis (Molina, 1782); Phylum Chordata; Subphylum Urochordata; Class Ascidiacea, common local name “piure” or sea squirt; a filter-feeder (plankton and suspended particles) sessile species; may play an important role in monitoring domoic acid (DA) the principal toxic component of Amnesic Shellfish Poisoning (ASP). Significant DA concentrations have been determined in tunicate samples, collected during a recent ASP outbreak in Bahía Inglesa, an important scallop (Argopecten purpuratus) farming area. Several infaunal species were tested for the presence of DA, in addition to the usual scallop monitoring programme. DA was found at sub-toxic levels in filtering bivalves such as mussels (Mytilus chilensis), large mussels (Aulacomya ater) and clams (Protothaca thaca) (6.4, 5.4 and 4.7μgDA/g tissue respectively). Of particular interest was the observation of significant accumulations of toxic Pseudo-nitzschia sp. diatoms in the internal siphon and atrium spaces of the tunicate. Toxin distribution within major tunicate organs was heterogeneous with 8.7–15.5μgDA/g in edible tissues, 14.9–17.9μgDA/g in the fecal material and 13.6–32.7μgDA/g in the gut content. DA was determined by HPLC–UV and confirmed by diode-array detection and LC–MS/MS analysis. This is the first report of the presence of DA in a tunicate that is regularly consumed by coastal populations. These results confirm the need to include these organisms in sanitation programs for marine toxins. [Copyright &y& Elsevier]

Sustainability of cities should largely be based on the ecological capital represented by vegetation, which constitutes an alternative for the study of environmental pollution. In order to determine the capacity of sulfur accumulation in tree species, samples of leaf material were taken from 225 trees located in the city of Chihuahua taking into consideration commercial and land uses, mixed and heavy industry and low and middle class residential areas. At the species level, quantities of sulfur exceeded optimal levels for their development. Using General Linear Analysis interactions between species, site and season were tested for sulfur content in each tree, determining a significant interaction between season and site factors (P<0.0235). These results provide data for urban environmental policies and the need for finding species that determine environmental quality. [ABSTRACT FROM AUTHOR]

Abstract: In the light of using biomaterial as pollutants sorbents for the environmental biomonitoring, we report here the results of the absorption of polycyclic aromatic hydrocarbons (PAHs) by pine bark. Quantitative analysis of 19 different polycyclic aromatic compounds was performed, after Soxhlet extraction in dichloromethane, by means GC–MS technique. Pinus was chosen due to its wide distribution in the Mediterranean area. The passive absorption of PAH by pine bark in the metropolitan areas allowed us to evaluate the air quality of Palermo. The obtained results showed a very high range of PAHs concentrations, from 33μg/kg (bark dry weight), as ΣPAHs, at the control site to 1015μg/kg along a road with high traffic flow. [Copyright &y& Elsevier]

Abstract: Monthly variations of total glutathione, glutathione-S-transferases, glutathione peroxidase, glutathione reductase, glyoxalase I, glyoxalase II, and catalase were studied in Lophopus crystallinus, a freshwater bryozoan, collected from Lake Piediluco. Specimens were sampled during the vegetative period from November to April for two different cycles: cycle I from 1996 to 1997 and cycle II from 1999 to 2000. Simultaneously, analyses of heavy metal content such as lead, cadmium, chromium, nickel, copper, iron, and zinc were determined in the samples of L. crystallinus. Specimens of cycle II displayed highest chromium and iron accumulation and elevated levels of biochemical parameters. Total glutathione content, catalase, and glutathione peroxidase activities, were related with the highest metal concentrations in L. crystallinus from Lake Piediluco. [Copyright &y& Elsevier]

The leaves of Pelargonium zonale have been chosen because this plant is widespread in both the Mediterranean metropolitan and peripheral areas. The paper describes the analytical method, and the results concerning the determination of PAHs in Pelargonium leaves collected in the Palermo area, and their possible origins. The GC-MS method was applied, since identification of all the different compounds with spectra libraries is possible. Samples were analyzed for 22 PAHs. The reported analytical method is complete within 2 hours, and more convenient than that of other researches. Total PAH concentrations in leaves varied between 24–357 μg/kg d.w. The relative abundance of the analyzed PAHs can be used to elucidate the sources. PAH concentrations were positively correlated to those of particulate measured by traditional methods. The results clearly indicate that the chosen PAH levels in Pelargonium leaves offer the possibility to assess the quality of air in determined geographical areas. The city of Palermo is prone to a rather high level of atmospheric pollution, in particular in the zones with heavy traffic. Industrial activity is widespread in the area, but not an important source of the pollutants studied here. [ABSTRACT FROM AUTHOR]

• First report of Centella asiatica as a possible cadmium phytostabilizer. • Growth and physiological tolerance to increasing concentrations of soil cadmium. • Twenty five folds increase in centelloside content observed. • Low cadmium accumulation in aerial parts as compared to roots. • Hence, leaves can be harvested for pharmaceutical benefit. The present study explores the effect of varying concentrations of soil cadmium (50−200 mg/kg soil) and lead (200−800 mg/kg soil) on glasshouse grown plantlets of Centella asiatica. The plantlets were fairly tolerant to soil cadmium and lower concentrations of lead in terms of biomass accumulation. Application of 200 mg/kg soil cadmium concentration, led to enhanced biomass/two-fold increase in shoot length and a significant accumulation of cadmium in shoots and roots. Specific activities of anti-oxidant enzyme systems such as superoxide dismutase, ascorbate peroxidase, and guaicol peroxidase were also found to be elevated under treated conditions. Interestingly, the ratio of cadmium concentration in roots: soil (bioaccumulation coefficient factor) was more than 1, Centella asiatica could be a potential bioaccumulator of cadmium. Also since translocation of cadmium from roots to shoots was less than 40 %, the leaves, accumulating more than twenty five fold more centellosides (in 200 mg/kg soil cadmium v/s control conditions) could also be potentially exploited for phytochemicals with minimum post-harvest processing. Real time PCR analysis also revealed higher population of centelloside biosynthetic gene transcripts such as squalene synthase, farnesyl pyrophosphate synthase, β amyrin synthase, as compared to control conditions. Plant growth, although tolerant to lower concentrations of soil lead could not effectively accumulate lead in roots, and centelloside contents was also found to be only marginally higher than control. This study reports the possibility of exploiting C. asiatica as potential plant systems that may be cultivated on cadmium contaminated soils to reap phyto-pharmaceutical benefits. [ABSTRACT FROM AUTHOR]

Com o objetivo de estudar a absorção e translocação de Ca, Co, Fe, K e Zn em Aechmea blanchetiana, plantas foram cultivadas in vitro em meios de cultivo contendo concentrações de Zn (0,0; 0,18; 1,8; 18 e 180 mg Zn L-1). Após 16 semanas de cultivo, os sistemas aéreo e radicular foram separados e determinadas à massa seca para massa de matéria seca e para a análise por ativação com nêutrons (AAN). O procedimento consistiu em irradiar amostras e padrões no reator nuclear de pesquisa IEA-R1 por 16 h para análise por espectrometria de raios gama. O controle dos resultados foi avaliado por meio das análises dos materiais de referência certificados, com desvios padrão relativo de 9,1 % e erros inferiores a 12,9 %. Os resultados das determinações dos elementos mostraram que o Zn alterou absorção e translocação de Ca, Co, Fe, K e Zn. A espécie apresentou alta quantidade de Zn nos sistemas aéreo e radicular indicando, possivelmente, ser bioacumuladora desse elemento.

In this study, we review research conducted in the La Spezia district during 1989, 1992, and 1994, using lichens and moss as indicators of air pollution. SO2 pollution was examined by means of anIndex of Atmospheric Purity (IAP) based on the frequency of epiphytic lichen within a sampling grid. Metal deposits were estimated using the lichen Parmelia caperata and the moss Hypnum cupressiforme as bioaccumulators. IAP maps show progressive air quality improvement from 1989 to 1994. This trend correlates to a decrease in SO2 emissions during recent years that is attributed to the use of methanefor residential heating and the closing of a coal-fired power plant.Metal contamination maps show that the most polluted area is now in the southeastern part of the gulf. The pattern of pollution coincideswith the location of the chief pollution sources in the area. From 1989 to 1994, the metal concentrations in lichens decreased, but metaldeposits in the southeastern area were cause for concern. High concentrations of lead in the area are related to emissions from a waste incinerator and a plant that produces lead oxide. Epidemiological investigations reveal that the area population has the highest levels of lead in their blood. The use of bioindicators and bioaccumulators permits long-term and large-scale monitoring of environmental pollutant levels in full agreement with traditional methods. [ABSTRACT FROM AUTHOR]