Indicators Of Metal Pollution Research Articles

Analysis of two coastal pelagic fish species (Sardinella aurita and Scomber colias) for early detection of the impact of anthropogenic metals released into the marine environment

In this study, the concentrations of several metals (Al, Cd,Cr, Cu, Fe, Pb, Zn) were analyzed in two species of fish (S. aurita and S. colias) in different years, including the period of the COVID-19 pandemic. The highest values of metals such as Al were found in the years 2019 8.661±0.434 mg/kg in S. colias and 6.487±1.485 mg/kg in S. aurita, and the year with the lowest concentration was 2020; 7.5±0.146 mg/kg in S. colias and 4.405±0.823 mg/kg in S. aurita, this pattern of concentrations occurs similarly for the other metals studied. Significant differences were found in the concentrations of these metals in both types of fish over the years. In general, metal concentrations were higher in 2019 and lower in 2020, coinciding with the period of reduced human activity during the pandemic. During the COVID-19 pandemic, reduced human activity led to a decrease in metal pollution in the marine environment, which had a positive impact on fish. However, it was noted that these effects may be temporary and may reverse when normal economic activities resume. These two fish species are sensitive indicators of metal pollution in the marine environment and it is important to take measures to reduce the release of contaminating metals into the environment. The need to adopt sustainable tourism practices and stricter environmental regulations to protect marine ecosystems is also mentioned.

Assessing the deposition of heavy metals in edaphotopes and synantrophy vegetation under the conditions of technological pollution of the city

The object of this study is a regional center with a developed industry and a significant traffic load. The study provides an assessment of the impact of the urbanization process on the conditions of development of urban edaphotopes and their role in the functioning of urban ecosystems. It was determined that the geochemistry of the soils of urban ecosystems is significantly different from natural landscapes, which is due to the symbiosis of natural and anthropogenic factors. The content of mobile forms of heavy metals in the soil of 14 localities of different functional zones within the city was investigated. A comparative assessment of the spatial heterogeneity of the content of heavy metals in the vegetative organs (root, shoot) of the diagnostic species Polygonum aviculare L. was performed. Based on the sources of emission of heavy metals and the formed geochemical anomalies, a direct dependence was established on their accumulation by the vegetative organs of Polygonum aviculare L. According to the calculated biological absorption coefficient (BAC), high bioavailability for the accumulation of man-made toxicants Cu, Zn, Pb, Cd by the phytomass of Polygonum aviculare L. was proven. It was determined that the content of heavy metals in different parts of the test object is due to their physiological ability to accumulate these toxicants in the root and above ground mass. Active translocation of toxicants from the soil to the roots is characteristic of localities with intense influence of man-made factors, for which the value of the bioavailability coefficient varies within 0.6>BAC<0.85. Correlation coefficients between the content of heavy metals in the atmosphere, soil, and vegetative organs of the plant were determined. The research allows us to evaluate the prospects for using Polygonum aviculare L. as a cumulative indicator of metal pollution in urban technogenic ecosystems and their high phytoremediation value under conditions of environmental pollution with heavy metals

A biomonitoring study of Diadema setosum: metal bioaccumulation and current status in Iskenderun Bay, eastern Mediterranean

Concentrations of aluminum, chromium, cobalt, nickel, cadmium, lead, manganese, iron and zinc were determined in sea urchin species, Diadema setosum from Iskenderun Bay in December 2022. The level of metals was determined by Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Concentrations of the heavy metals in the examined sea urchins ranged as follows: Al 0.07-7.17 µg g-1; Cr 0.07–0.8 µg g-1; Co 0.01–0.2 µg g-1; Ni 0.2–2.9 µg g-1; Cd 0.0–0.02 µg g-1; Pb 0.4-3.5 µg g-1; Mn 0.03–0.4 µg g-1; Fe 1.2-57.2 µg g-1; Zn 0.28–2.7 µg g-1, respectively. The highest accumulation of Fe and Pb metals was determined in the tissues of the sea urchin. The present study suggests that D. setosum could be a potential biological indicator of metal pollution in the İskenderun Bay. Furthermore, soft tissues generally had lower levels overall. For this reason, the data show that D. setosum is a very good heavy metal collector and therefore may be used successfully to monitor heavy metal levels in Iskenderun Bay.

Assessment of metal trace elements in the echinoderm Paracentrotus lividus from the North-Eastern coast of Algeria

The echinoderm sea urchin Paracentrotus lividus Lamarck, 1816 (Echinodermata, Echinoidea) is a good species to be used in environmental and toxicology research, in particular as a heavy metal bio-indicator. Our study’s objective is to evaluate the amounts of Zn, Pb, Fe, and Cu in sea urchin specimens collected from the coast of Skikda (Northeast Algeria) in order to validate the fact that sea urchins are good indicators of metal pollution and can be used effectively for environmental biomonitoring. To realize our objectives, three sampling sites were chosen based on suspected forms and sources of contamination. The main physicochemical parameters of the seawater were measured to determine their quality. 15 specimens of urchins in each station were obtained from exposed rocky surfaces and transported to the laboratory. Before dissection, the biometric parameters and the total wet weight were determined. The soft organs (gut and gonads) of individuals were separated and utilized to evaluate the levels of heavy metals. The condition index and metal indices were also determined. Our study confirmed that P. lividus may be considered a valuable bioindicator of heavy metal contamination in marine ecosystems. The results show that the amounts of heavy metals differed significantly between stations. Samples taken from the Larbi Ben M’hidi station showed greater amounts of Pb, Zn, and Cu. These amounts are above the recommended limits for fish and aquatic animals. Also, the heavy metals found in sea urchins vary depending on the physicochemical parameters, trace metals in the seawater, and the individual biometric parameters. These higher concentrations of metals in seawater and in P. lividus individuals at the Larbi Ben M’hidi station are largely caused by the construction of a massive oil industry complex and terminal with several refineries and petrochemical units near this station, as well as by a considerable amount of domestic wastewater. Finally, to avoid this metallic pollution risk, it is necessary that permanent controls be imposed as soon as possible. Urban and industrial wastes must be treated before being released, in the hope of reducing future metal concentrations.

Biomonitoring of heavy metals using Contracaecum quadripapillatum (Nematoda) in comparison to its fish host, Lates niloticus, from the Nile River, Egypt

Recently, fish parasites have been used as a biomonitoring tool to indicate the health status of ecosystems. Therefore, this research aimed to evaluate the potential capacity of Contracaecum quadripapillatum larvae as accumulation indicators for metal pollution and compare metal concentrations in host tissues of non-infected and infected fish: Lates niloticus from the Nile River. Accumulations of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in larval nematodes and tissues of the liver, kidney, and muscles of both infected and non-infected fish were determined. All metal concentrations exhibit a significantly higher increase in larval nematodes than the muscles of infected fish and vice versa except Cd in the kidney. On the other hand, only Cd, Mn, Pb, and Zn concentrations were significantly higher in the parasite than in the host liver. Therefore, bioaccumulation factors were most obvious and effective in the muscles of infected fish than in the liver and kidney. Contracaecum larvae accumulate Cd and Pb more than other metals. The infrapopulation size of C. quadripapillatum correlated with metal concentrations in different host tissues, especially the kidney, while the correlations between metal levels in the tissues of both parasite and fish organs exhibit different patterns in each organ. The current work revealed that C. quadripapillatum larvae represent environmental monitors for metal pollution in the freshwater ecosystem.

The Potential Role of Soil Bacteria as an Indicator of Heavy Metal Pollution in Southern, Iraq

The present study was performed to spotlight the potential role of soil bacteria in the Al-Rumaila oil field as a bioindicator of heavy metals pollution. For this purpose, nine soil samples were collected from different sites, with 20cm depth, to assess the pollution status depending on the total and available concentrations of heavy metals. The result indicates pollution of the studied soils with the following metals: Cd, Cu, Fe, Zn, and Pb. The mean of total concentration for all studied metals was higher than the allowed maximum limit based on the international limit:(3.394, 3.994, 39.993, 8844.979,150.372, and 103.347 µg/g), respectively. While measuring the total Metal concentration is important in determining the degree of pollution in the environment; it cannot be depended to determine their impact on the living organisms. In the present study the means of available concentration of studied metals were as follows: 0.015, 0.787, 0.021, 0.515, and4.304 µg/g. respectively, which were lower than their total concentration. Different types of bacterial genera (Serratia marcescens, Sphingomonas paucimobilis, Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus lentus) were isolated from the same soil. And broadcasts through the results their presence in all studied soils. Therefore, the isolated bacteria play a significant role as an indicator of metal pollution in the soil, which was proved through the result of the Minimum inhibitor concentration (MIC), which indicated a high tolerance ability towered these metals.

Does environmental metal pollution affect bird morphometry? A case study on the tree sparrow Passer montanus

Morphological characteristics are the leading indicators of the health status of birds. To explore the effects of heavy metals on bird morphometry in natural populations, tree sparrows (Passer montanus) were studied in a polluted site [Baiyin (BY)] and a relatively unpolluted site [Liujiaxia (LJX)]. This study aimed to examine whether morphological variables, the fluctuating asymmetry (FA) of the wing, tarsus, and toe length, were associated with heavy metals (Cu, Zn, Pb, and Cd) and Ca levels in different tissues and feces of adults and nestlings. Results showed that adults collected from BY contained relatively higher heavy metal concentrations and lower Ca concentrations in different tissues than those from LJX. Smaller body sizes and higher FA levels of adults and nestlings were found in BY than in LJX. Although higher heavy metal concentrations in some tissues were associated with smaller morphological characteristics of adults, the effects were not obvious in nestlings. The most correlated heavy metal with as many characteristics was heavy metal in primary feather in both sites, and the most affected characteristic was body mass in BY. The FA values of adults and nestlings in BY were positively affected by heavy metal concentrations in different tissues and feces. The growth rate of wing and tarsus length of nestlings in BY were negatively affected by the FA values of wing and tarsus length, respectively. Taken together, environmental metal pollution might affect the morphological characteristics of tree sparrows. These findings suggest that the morphological characteristics of tree sparrows, especially FA, can be used as indicators of metal pollution, underscoring the importance of measuring morphological characteristics in avian ecotoxicology field studies.

Toxicity and accumulation of lead and cadmium in the land snail, Archachatina papyracea, in a tropical Alfisol from Southwestern Nigeria.

Snails are an important link in the transfer of contaminants, especially metals in the food chain. Yet, few studies have examined the toxicity and accumulation of metals in snails in the tropics. This study assessed the toxicity and accumulation of two non-essential metals (cadmium and lead) to the tropical snail Archachatina papyracea. Specimens of the snail A. papyracea were exposed in a loamy soil collected from Ile-Ife, Nigeria and spiked with varying concentrations of Cd and Pb over 28days. Survival and weight change of snails were monitored weekly, while tissue accumulation was assessed at the end of the 28-day period. Survival was a more sensitive endpoint than the weight change of snails. The Cd median lethal concentration (LC50) value was 93 ± 4.4mg/kg, while the median effect concentration (EC50) for snail weight change was 131 ± 41mg/kg. For Pb, LC50 value was 1121 ± 457mg/kg, while the EC50 value for weight change was higher at 4541 ± 1180mg/kg. Therefore, Cd was a factor of about 10 to 30 × more toxic than Pb, consistent with findings on the relative toxicity of Cd and Pb to other soil organisms, including earthworms, springtails, and mites. Although not included initially as an endpoint, egg production in the snails decreased with increasing Cd and Pb concentrations in the substrate. Metal analysis of the foot and visceral mass of surviving snails showed progressive accumulation of Cd and Pb as concentration increased, showing the tendency to use body residue of A. papyracea as an indicator of metal pollution. It further suggests the role of this snail species in above-ground metal transfer in the food chain and highlights the potential danger for human consumption.

Late Glacial and Holocene environmental variability, Lago Trasimeno, Italy

Lago Trasimeno (central Italy), 10 km wide and < 6m deep, fills a basin of tectonic origin, and is one of Europe's few endorheic lakes. We report on a multidisciplinary stratigraphic study based on seismic reflection profiles and two sediment cores, aimed at providing information on the vegetational, lithological, and climate history of this area. Trace elements, palynology, macrofossils, organic carbon, and C isotopes, coupled with AMS C-14 dating, describe environmental changes from Late-Glacial to present. The base of the cores records a Late-Glacial steppic vegetation (Poaceae, Artemisia, Amaranthaceae), with dry and cold conditions and a high charcoal/pollen ratio. An ensuing shift to a warmer and moister climate is shown by the rise of Pinus and Quercus, and shallow water aquatics such as Nitella. Early Holocene warming, indicated by Quercus, Oleaceae, Corylus, and Betula, is followed by a hiatus suggesting one or more severe drought events between 9000 and 3000 yr BP. Late Holocene presence of Alnus and Fagus indicates increased moisture, probably in winter, which would have increased lake level. Heavy metal pollution indicators (Pb, Cu, Zn) in the upper portion of the cores imply industrialization. Due to its location, to intensive and uninterrupted anthropogenic impacts since proto historical times, and to its shallow depths, Lago Trasimeno provides an important observation point for climate and environmental changes in the central Mediterranean region during and before Holocene times.

The Danubian cryptic invader Theodoxus fluviatilis (Gastropoda: Neritidae) in the River Rhine: a potential indicator for metal pollution?

Metal pollution poses a major threat to aquatic systems especially in anthropogenic influenced areas, in as much as metals are persistent in the environment. The freshwater snail Theodoxus fluviatilis has often been used as an indicator species for the ecological status in river monitoring. In the River Rhine, the native Northern-European form of T. fluviatilis is nowadays extinct, whilst the Danubian form is spreading along the river. The aim of our study was to investigate if the cryptic invader is affected by metal exposure present in the River Rhine and to discuss its potential as an indicator for metal pollution. Several environmental abiotic (14 water environmental variables plus five common metal concentrations in water and biofilm) and biotic parameters (biofilm mass) were measured across 23 sites along the River Rhine. Five population and six histopathological parameters were evaluated on snails collected at all 23 sites. Aqueous chromium concentration was positively correlated to the damage of male reproductive organs of T. fluviatilis, and higher ammonium concentration was correlated to a decrease in snail size and an increase in the proportion of juveniles. None of the analysed snail parameters was negatively correlated to concentrations of other metals measured, like copper and zinc. Therefore, based on the parameters evaluated, our results indicate that the Danubian form of T. fluviatilis is only restrictedly suitable as an indicator for metal pollution in the River Rhine system. Further field and laboratory investigations including other stressors are necessary to evaluate the indicator potential of the cryptic invader holistically.

An assessment of trace metal pollution indicators in soils around oil well clusters

Due to the metallic ion constituents of crude oil, environmental levels of toxic metals are often exacerbated when oil is spilt. Biseni community plays host to numerous oil production companies in Bayelsa state, Nigeria. However, the tendency for this clan to be flooded, particularly owing to its lowland features has continued to negatively impact on the environment. Sometimes, floods are accompanied by spilt residual oil that encroach living areas, thus leading to the contamination of open water bodies, underground water resources, and fish and crop farms. This study surveyed the impact of oil seepages from oil well clusters on the overall soil quality by applying trace metal pollution indicators. Trace metals were analyzed by atomic absorption spectrometry, and concentration ranged from 5893.0-6263.8 mg/kg, 0.03–11.52 mg/kg, 3.15–6.46 mg/kg, 4.46–58.64 mg/kg, 13.61–29.83 mg/kg, 0.23–0.73 mg/kg, 8.32–20.69 mg/kg, and 4.24–9.31 mg/kg for iron, copper, nickel, lead, zinc, cadmium, chromium and cobalt respectively. Concentrations were within target limits stipulated by the Department of Petroleum Resources, Dutch standard limit and World Health Organization. Zinc and chromium showed the strongest correlation (r = 0.92, p < 0.05) in the study area, whilst one-way ANOVA revealed equality (p > 0.05) among the different sampling points. This is evidence that the field area is affected by similar contamination source. Whereas, the micro-pollutant metals depicted significant variability (p < 0.05), probably due to the outlier concentration of iron. Overall, lead was the most contaminating metal, while location BNS2 (0.3m) was the most considerably contaminated area. Enrichment factor revealed the anthropogenic origination of lead. Index of geo-accumulation of lead ranged from moderate to heavy contamination, with lead recording very high contamination factor, and the degree of contamination depicting considerable risk, especially at the top soil. Pollution load index showed most contamination (moderately polluted) at BNS2. Quantification of contamination showed relative contamination for most locations, whereas potential ecological risk index mostly depicted low risk, apart from the exhibition of moderate risk of lead and cadmium at BNS2. Conversely, sum of pollution indices and risk index revealed low contamination and low risk respectively.

Assessing Metal Content in Halophila stipulacea Seagrass as an Indicator of Metal Pollution in the Northern Gulf of Aqaba, Red Sea

Assessing Metal Content in Halophila stipulacea Seagrass as an Indicator of Metal Pollution in the Northern Gulf of Aqaba, Red Sea

Bird Feces as Indicators of Metal Pollution: Pitfalls and Solutions.

Bird feces are commonly used as a proxy for measuring dietary metal exposure levels in wild populations. Our study aims to improve the reliability and repeatability of fecal metal measurements and gives some recommendations for sampling. First, we studied levels of variation in metallic element (arsenic, calcium, cadmium, cobalt, copper, nickel, lead) concentrations: temporal variation within an individual, among siblings in a brood and among-brood/spatial variation. Second, we explored the variation caused by dual composition (urate vs. feces) of bird droppings. Two sets of fresh fecal samples were collected from pied flycatcher (Ficedula hypoleuca) nestlings living in a metal polluted area in summers 2017 (dataset 1) and 2018 (dataset 2). We found a great deal of temporal intra-individual variation in metal levels, suggesting that dietary exposure varied markedly in a short time scale (within a day). A sample from only one nestling per brood did not well describe the brood mean value, and we recommend that at least four siblings should be sampled. Brood level samples give relatively good temporal repeatability for most metals. For all the metals, the levels in the fecal portion were more than double to those in the urate portion. Since the mass proportion of urate in the bird droppings varied a great deal among samples, standardizing sampling, e.g., by collecting only the fecal part, would markedly reduce the variation due to composition. Alternatively, urate portion could be used for biomonitoring of internally circulated bioavailable metal.

Fish as bio indicators to determine the effects of pollution in river by using the micronucleus and alkaline single cell gel electrophoresis assay

ObjectivesThe unpolluted freshwater is an essential ingredient for the healthy life of animals and humans. Aquatic pollution is the most important problem for living organisms. The main source of water pollution is industrial sewages. In the current study bioaccumulation and genotoxic effects of different metals e.g. Pb, Cd, Cr, Cu were determined in various tissues of Puntius sophore (P. sophore). MethodsThe water sample and fish P. sophore were brought from different sites of the Gomati river (coordinates: 25°30′29″N83°10′11″E), India. The heavy metals in water and fish tissues were determined by using ICP-MS. The mutagenic and genotoxic potential of the river water in P. sophore were evaluated using micronucleus and single-cell gel electrophoresis techniques. ResultsWe have observed that the concentration of heavy metals (Pb, Cd, Cr, Cu) in the river water and bioaccumulation of these metals in P. sophore are equal in order. Thus it was confirmed that fish act as a sentinel indicator of metal pollution of the surrounding environment. The formation of micronuclei, as well as fragmentation of DNA, were significantly increased (p < 0.05, 0.01) in river fish as compared to the control. ConclusionsThus we might consider the fish for biomonitoring of aquatic ecosystems. Also, these findings confirmed that water of the Gomati river was contaminated with heavy metals. So, it is important to prevent the inflow of domestic and industrial sewage in the river.

Facing the threat: common yellowjacket wasps as indicators of heavy metal pollution

We investigated the common wasp, Vespula vulgaris as a bioindicator and biomonitor of metals in the industrial area. Using traps, we collected 257 yellowjackets along a pollution gradient in the Harjavalta Cu-Ni smelter in Southwest Finland. Our method detected metal elements such as arsenic (As), cobalt (Co), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), zinc (Zn), and mercury (Hg) in wasps. The data analyses revealed V. vulgaris can be a proper indicator for As, Cd, Co, Cu, Ni, and Pb, rather than for Fe and Zn contamination. Body burdens of As, Cd, Co, Cu, Ni, and Pb decreased with an increase in distance from smelter. Enrichment factor (EF) followed the pattern Pb ˃ Cd ˃ As ˃ Co ˃ Cu ˃ Ni. The highest bioaccumulation (BAF) values were revealed for Cd (5.9) and the lowest for Pb (0.1). Specially designed software (WaspFacer) allowed revealing body burdens of As, Cd, Co, Cu, Ni, and Pb to be associated with rather smaller than more asymmetric facial colour markings in yellowjackets. These results add to the body of literature on how heavy metal contaminants can have tangible phenotypic effects on insects and open future opportunities for using wasps as indicators of metal pollution.

Distribution Spread and Environmental Risk Status of Pb, Cd And Cr in Soils of an Open-Air Waste Dumpsite along Tombia/Amassoma Road in Yenagoa Metropolis

In spite of the popularity of open-air waste dumping in Nigeria, it remains a relatively less effective waste management option across the globe because of its associated environmental impacts which includes the release of green house gases (GHGs), persistent organic pollutants (POPs), and metal micro-pollutants amongst others. This study aims to assess the potential environmental risks associated to metals released and vertically delineated across the soil profile within surroundings of dumpsite. Heavy metals in soil samples were acid-digested using the aqua-regia mixture of hydrochloric and nitric acid, followed by instrumentation analysis using the GBC 908 PBMT model atomic absorption spectrophotometer. Contaminated sites showed metal concentrations ranging from 1.493 to 109.460 mg/kg, 0.133 to 4.237 mg/kg, and 5.200 to 25.367 mg/kg for lead, cadmium and chromium respectively, with location 1 land area showing the most contamination. Only soil chromium was observed within regulatory stipulations in all cases. There was significant variation (p &lt; 0.05) between the different sample locations, thereby indicating variations in composition of dumped wastes. Lead and cadmium showed the strongest positive correlation (r = 0.855, p &lt; 0.01) and the application of some heavy metal pollution indicators revealed relatively higher metal loads and degree of contamination, as well as depicting potential ecological risk for soils of location 1. The significant heavy metal contamination of soils in the Tombia-Amassoma waste dumpsite requires that the local environmental sanitation and regulatory authorities take necessary remedial action to forestall the escalation of public health concerns that may emanate from this open-air dump.

СОДЕРЖАНИЕ ТЯЖЕЛЫХ МЕТАЛЛОВ В РАСТЕНИЯХ ГОРОДА ПЕТРОПАВЛОВСКА-КАМЧАТСКОГО (КАМЧАТСКИЙ КРАЙ) В 2017–2018 гг.

Results of determining the content of zinc, copper, lead and cadmium in the leaves of Alnus hirsuta, Artemi-sia vulgaris kamtschatica, Betula ermanii, Rosa amblyotis, Salix udensis collected from the territories of Petropavlovsk-Kamchatsky in 2017–2018 summer period are discussed. In the summer of 2017, the copper content in the plants from studied areas varied in the range from 5.5 to 22.5 mg/kg, in 2018 – from 7.7 to 36.6 mg/kg. Its highest content in 2017 and 2018 was found in A. vulgaris, and the lowest in R. amblyotis. In 2017, the concentration of zinc varied from 12.9 to 281 mg/kg, in 2018 – from 20.8 to 246 mg/kg, the high-est concentration in 2017 and 2018 is typical for S. udensis, the lowest for R. amblyotis. In 2017, the range of lead content in plant samples was from 0.3 to 3.0 mg/kg, in 2018 – from 1.2 to 3.8 mg/kg. In the summer of 2017, the cadmium content in studied plant samples varied in the range from 0.2 to 2.7 mg/kg, in 2018 – from 0.1 to 3.6 mg/kg. The lowest concentration of cadmium was found in 2017 in R. amblyotis, in 2018 – B. ermanii, the highest in the leaves of S. udensis in 2017 and 2018. Our results allowed identifying species – indicators of metal pollution for the territories of Petropavlovsk-Kamchatsky: A. vulgaris kamtschatica from the representatives of the herbaceous-shrub layer and S. udensis from the tree layer.

Evaluation of benthic macroinvertebrates as indicators of metal pollution in Brazilian rivers

ABSTRACT The evaluation of water resources quality is an important tool for controlling and monitoring water bodies, among which, the evaluation of toxic metal levels in benthic macroinvertebrates has been highlighted. This study aimed to evaluate the biological quality of the Alvorada and Mandaguari rivers and to evaluate the metal bioaccumulation by means of the metal concentrations in surface waters, bottom sediments and benthic macroinvertebrates. Samples of water, biological material and sediments were conducted at six sampling points, 3 points in each river during 12 months. Macroinvertebrates were sorted, identified and analysed from the biological metrics, BMWP′ index and statistical analyses. The samples of benthic macroinvertebrates and sediments were submitted to nitroperchloric digestion for further determination of the metal content. The metal concentrations in sediment had become high in both rivers, reaching values of up to 1752.50 mg kg−1 of Pb in point M1 and 53.80 mg kg−1 of Cd in point M3. Macroinvertebrate tissues exhibited high levels of toxic metals, reaching values of 146.11 mg kg−1 of Cr in point M1, 144.28 mg kg−1 of Pb and 3.11 mg kg−1 of Cd in point M3, which indicates the occurrence of bioaccumulation and insertion in the food chain. The results from the evaluation using the BMWP′ index do not present the real conditions of the watersheds, which suggests a review of the evaluation method. In addition, the environmental evaluation using macroinvertebrates is a good tool to verify the impacts in a river.

Evaluation of the Cadmium Accumulation in Tamarillo Cells (Solanum betaceum) by Indirect Electrochemical Detection of Cysteine-Rich Peptides.

Long-term cadmium intake can be very dangerous to human health due to its toxic effects. Although people can be contaminated with this element from different sources, contaminated food is probably the most important one. Foods such as vegetables and fruits can become contaminated with cadmium existing in soils, irrigation water, or chemical fertilizers. Some plants produce an excess of cysteine-rich peptides (CRp) when affected by high concentrations of heavy metals such as cadmium, thus indicating the presence of this type of contamination. Among these plants is tamarillo (Solanum betaceum), which is locally known as “tree tomato”. This is a native plant widely consumed in the Ecuadorian Andes because of its abundance, low cost, and high content of vitamin C and fiber. The fact that Solanum betaceum produces CRp upon contamination with heavy metals means that this plant may be able to accumulate heavy metals. If this is the case, the plant can possibly be used as an indicator of metal pollution. The main goals of the present work were to evaluate the possibility of using Solanum betaceum as an indicator of metal contamination in plants and to examine its capability to accumulate metals. Both goals were met by determination of the amounts of CRp produced by Solanum betaceum cells cultivated in vitro in the laboratory under controlled conditions in the presence of different concentrations of cadmium. The CRp determination was carried out by means of electrogeneration of iodine in an iodide solution containing reduced glutathione as a biological thiol model. Solanum betaceum cells were grown in a Murashige and Skoog solution enriched with a 30 g L−1 sugar aqueous solution and 1 mg L−1 2,4-dichlorophenoxyacetic acid. The results of these experiments confirmed the following: (1) CRp production is a function of the amount of cadmium present as a contaminant up to a limiting value after which cell apoptosis occurs; (2) Solanum betaceum accumulates cadmium; (3) the analytical method used is appropriate for CRp determination; and (4) CRp determination is a valid alternative to detect contamination by heavy metals in plants.

Variations in tree sparrow (Passer montanus) egg characteristics under environmental metal pollution

Environmental metal pollution is known to adversely affect bird reproduction, for which the variations of egg characteristics are considered very important. Our study explored whether variations in egg characteristics, such as egg volume, eggshell spotting pattern, eggshell coloration, and eggshell thickness, were correlated with heavy metal levels (Cu, Zn, Pb, and Cd) and Ca levels in the eggshells of tree sparrows (Passer montanus), a widespread passerine species. Eggs were collected from a long-term heavy metal polluted area (Baiyin, BY, northwest China) and a relatively unpolluted area (Liujiaxia, LJX, northwest China). Our results showed that the embryonated (eggshell: Cu: p = 0.003, Pb: p = 0.002) and non-embryonated (egg contents: Pb: p = 0.044, Ca: p = 0.045) eggs collected from BY contained relatively higher metal concentrations than those from LJX. Eggs from BY were smaller in volume (p < 0.01) and thinner in eggshell thickness (p < 0.01) than those from LJX. Mean egg volume increased with clutch size in BY (p = 0.017), which was also accompanied by an increase in the within-clutch coefficient of variation (CV) for egg volume (p = 0.045). Clutches with a higher CV for egg volume tended to contain higher concentrations of Zn and Pb (Zn: p = 0.084; Pb: p = 0.081) in the eggshells from BY. No differences were found in the eggshell spotting coverage ratio of eggs; however, eggshells were much darker in BY than in LJX. A more aggregated eggshell spotting distribution indicated higher eggshell Zn and Pb levels (BY: Zn: p = 0.040, Pb: p = 0.076; LJX: Pb: p = 0.066). The results demonstrate that the egg characteristics of tree sparrows can be used as indicators of metal pollution, especially for the within-clutch CV for egg volume, eggshell spotting pattern and eggshell coloration.