Metal Bioconcentration Research Articles

Effects of Organic Manure on Wheat Yield and Accumulation of Heavy Metals in a Soil—Wheat System

The application of organic manure is an effective way to develop sustainable agriculture. However, the application of organic manure may be associated with a potential risk of heavy metal pollution for soil and crops. In this study, the effects of organic cow manure (T1) (as base fertilizer), organic pig manure (T2) (as base fertilizer) and chemical fertilizer (T3) on winter wheat grain yields, grain quality, heavy metal concentrations and heavy metal bioconcentration factors (BCFs) in a soil–wheat system were studied from November 2021 to June 2023. The results showed that the winter wheat grain yields in the T1 and T2 treatments were lower than those in the T3 treatment by 2.57–38.0% and 10.5–25%, respectively. There were no significant differences in quality indexes of winter wheat grain among different fertilizer treatments. The concentrations of heavy metals in topsoil and winter wheat were 0.12–76.11 μg/g and 0.01–43.25 μg/g, respectively. The BCFs of heavy mental in the soil–wheat grain system was 0–2.92. In general, there were no significant differences in heavy metals’ concentrations in topsoil and wheat grain among different fertilizer treatments. In summary, compared with chemical fertilizer, the short-term application of organic manures had no significant effect on heavy metals concentrations in topsoil and wheat.

Bio-concentration of heavy metals in marine crustaceans' hemolymph: insights from Oman Sea, Iran

Bio-concentration of heavy metals in marine crustaceans' hemolymph: insights from Oman Sea, Iran

Bioconcentration of Heavy Metals with Toxic Potential in Soil and Plants in Residential Areas

Bioconcentration of Heavy Metals with Toxic Potential in Soil and Plants in Residential Areas

Comparison among native floating aquatic macrophytes for bioconcentration of heavy metals

This work was aimed to show the development of a comparative study of the capability of bioindicators to reveal the presence of heavy metals among species of floating aquatic macrophytes such as Spirodela sp (giant duckweed), Pistia stratiotes (water lettuce), Salvinia sp used as a parameter for bioconcentration factors plant / sediment. We performed a simple sampling at six sites in the region of Pelotas, southern Brazil, in which it was collected sediments and plants. The plants experienced the nitric perchloric acid digestion method, while the sediment suffered pseudo total acid digestion method. The determination of Cr, Cu, Pb and Zn in the extracts was conducted by atomic absorption spectrophotometry in flame. In general, the floating aquatic macrophytes studied showed better bioconcentration factor for metals from the sediment in the following order: Cu>Zn>Pb>Cr. For copper, the figures obtained with Pistia stratiots ranged from 5.7 to 82.8. The BCF for Zn ranged from 3.0 to 11.6 and Salvinia sp. For the Pb bioconcentration factor, it ranged from 5.4 to 0.6 in Spirodela sp. The in situ study showed that all species had high bioaccumulation potential, especially Pistia stratiotes that was employed to remove copper.

Altered biotoxicity of cadmium to freshwater green algae by different concentrations of polystyrene

Microplastic pollution has become a global problem, threatening water bodies and aquatic organisms around the world. Heavy metal pollution in the aquatic environment is an environmental issue of long-term concern, and relatively few studies have been conducted on the compound toxic pollution of freshwater algae by microplastics and heavy metals. Therefore, in this study, Cd and polystyrene (PS) were selected as representative heavy metals and microplastics in the environment, and the toxic effects of the two pollutants on freshwater algae were investigated by determining the biomass of algal growth, chlorophyll a content, and the bioconcentration of heavy metals. It was found that the two pollutants alone could inhibit the growth and photosynthesis of the algae, and the toxicity increased with the increase of concentration. When the two pollutants were combined, the toxicity of Cd depended on the concentration of PS, and both low (1 mg/L) and high (100 mg/L) concentrations of PS increased the toxicity of Cd in a synergistic manner, whereas the medium concentration (10 mg/L) of PS showed an antagonistic effect, which was able to inhibit the toxicity of Cd.

Evaluation of historical data on persistent organic pollutants and heavy metals in Lake Baikal: Implications for accumulation in marine environments

Lake Baikal, the largest freshwater lake by volume, provides drinking water and aquatic food supplies to over 2.5 million people. However, the lake has been contaminated with recalcitrant pollutants released from surrounding industrial complexes, agriculture, and natural lands, thereby increasing the risk of their bioaccumulation in fish and seals. Yet, a collective analysis of historical concentration data and their bioaccumulation potential as well as what factors drive their accumulation in fish or seals remains largely unknown. We analyzed concentration data from 42 studies collected between 1985 and 2019 in water, sediment, fish, and seals of Lake Baikal. Heavy metals had the highest concentrations in water and biota followed closely by polycyclic aromatic hydrocarbons (PAHs) and organochlorines. Among organochlorines, polychlorinated biphenyls (PCBs) showed the highest levels in water, surpassing hexachlorocyclohexane (HCH) concentrations, particularly after normalizing to solubility. While naphthalene and phenanthrene exhibited the highest average concentrations among polycyclic aromatic hydrocarbons (PAHs), their relative concentrations significantly decreased upon solubility normalization. The analysis confirmed that bioconcentration and biomagnification of organochlorine pesticides, PCBs, PAHs, and heavy metals depend primarily on source strength to drive their concentration in water and secondarily on their chemical characteristics as evidenced by the higher concentrations of low-solubility PCBs and high molecular weight PAHs in water and sediment. The differential biomagnification patterns of Cu, Hg, and Zn compared to Pb are attributed to their distinct sources and bioavailability, with Cu, Hg, and Zn showing more pronounced biomagnification due to prolonged industrial release, in contrast to the declining Pb levels. Dibenzo-p-dioxins were detected in sediment and seals, but not in water or fish compartments. These data highlight the importance of addressing even low concentrations of organic and inorganic pollutants and the need for more consistent and frequent monitoring to ensure the future usability of this and other similar essential natural resources.

Комплексная оценка экологического состояния участка трансграничной реки Нарвы

A comprehensive study of the ecological state on the transboundary Narva River (Russia –Estonia border) downstream of Ivangorod, Kingisepp District, Leningrad Region, was carried out. It included the determination of chemical indicators of pollution of the natural river water, with an emphasis on some heavy metals content in water, sediments and soft tissues of local filter-feeding mollusks; the latter were used as bioindicators of river pollution in this location. Zn was determined in maximum concentrations in bottom sediments, then Cu, to a lesser extent Pb, Cd and Ni. The coefficient of metal bioconcentration calculated in soft tissues of mollusks showed maximum for Zn and Cu, to a lesser extent for Pb, Cd and minimum for Ni. However, such values have no negative effect on local biota as shown by physiological testing of bivalves from study site. The functional assessment of bivalves by non-invasive cardiac rhythm recording made it possible to characterize their functional status and adaptive capabilities as good. The relative abundance of hydrocarbon-oxidizing bacteria in the digestive tract of mollusks from the Narva River has been determined as an indicator of environmental pollution by oil products. It was noted that the number of hydrocarbon-oxidizing bacteria does not exceed the values characteristic of the reference waters of the Eastern Gulf of Finland. Based on the totality of the studies, it was concluded that the river waters in the studied location can be characterized as slightly polluted and its ecological status as of a good quality.

Impact of Translocation and Bioconcentration of Heavy Metals in the Area of Lignite-Fired Power Plant

Impact of Translocation and Bioconcentration of Heavy Metals in the Area of Lignite-Fired Power Plant

Toxic, genotoxic, mutagenic, and bioaccumulative effects of metal mixture from settleable particulate matter on American bullfrog tadpoles (Lithobates catesbeianus)

Amphibians are more susceptible to environmental stressors than other vertebrates due to their semipermeable skin and physiological adaptations to living in very specific microhabitats. Therefore, the aim of the present study was to investigate the effects of a metal mixture from settleable particulate matter (SePM) released from metallurgical industries on Lithobates catesbeianus tadpoles. Endpoints analyzed included metal bioconcentration, morphological (biometrical indices), hematological parameters (hemoglobin and blood cell count), and erythrocyte DNA damage (genotoxicity and mutagenicity). American bullfrog tadpoles (Gosner's stage 25) were kept under control condition (no contaminant addition) or exposed to a sub-lethal and environmentally relevant concentration (1 g.L−1) of SePM for 96 h. Tadpoles exposed to SePM exhibited elevated whole blood levels of Fe56, AL, Sn, Pb, Zn, Cr, Cu, Ti, Rb, V, Ce, La, Ag, As. SePM-exposed tadpoles showed a significant decrease in condition factor (12%) and increases in hepatosomatic index (25%), hemoglobin concentration (17%), and total leukocytes (82%), thrombocytes (90%), and monocytes (78%) abundance. In addition, exposed tadpoles showed higher MN and ENAs (340 and 140%, respectively) frequencies, and erythrocyte DNA damage with approximately 1.2- to 1.8-fold increases in comet parameters. Taken together, these results suggest that the multimetal mixture found in SePM is potentially genotoxic and mutagenic to L. catesbeianus tadpoles, induces stress associated with hematological changes, and negatively affects growth. Although such contamination occurs at sublethal levels, regulatory standards are needed to control the emission of SePM and protect amphibian populations.

Sources and Magnitude of Heavy Metals in Sugarcane Plantation Soils with Different Agricultural Practices and Their Implications on Sustainable Waste-to-Foods Strategy in the Sugar–Ethanol Industry

Driven by Thailand’s Bio-Circular Green Economy strategy, this study explores industrial waste utilization as a solution to mitigate the impacts of climate change and economic insecurity. This study involved interviews with farmers and field sampling across 131 sugarcane plantations, primarily in four districts in Kanchanaburi, western Thailand. The investigation aimed to assess heavy metal levels (As, Fe, Mn, Zn, Cu, Cr, Pb, Cd, Hg) in the plantation soils and their accumulations in soils and biomass under various agricultural practices, including the uses of filter cake and vinasse (industrial wastes from sugar–ethanol industries). Spatial analysis showed that As often exceeded national soil-quality standards for agriculture (25 mg kg−1). The Cd, As, and Zn tended to accumulate at a high level in most soils, whereas Pb accumulated locally. Factors such as clay content, soil alkalinity (for As and Mn), soil organic matters (As, Mn, and Hg), and no/minimum tillage (Zn and Cd) promoted the metal accumulation. Factor analysis showed that natural geochemical processes govern the spatial variations of the metals. The application of filter cake led to soils with elevated Cr, Fe, As, Cd, and Mn content and a clayey organic-rich composition, while the vinasse resulted in soils with higher levels of Zn, Cu, Fe, and clayey saline. The bioconcentration factors (BCF) revealed that sugarcane generally accumulated Hg (BCF ~2.32−35.72), whereas Cu (2.67) and As (1.04) tended to accumulate in sandy-soil farmlands. The waste utilization, however, neither contributed significantly to the concern levels of soil metals nor enhanced the bioconcentration of the soil metals into the sugarcane biomass. Utilizing the waste as fertilizer could benefit cane yield, but further studies should focus on proper fertilization rates and food safety.

A new omega-3 rich euglenoid Eutreptiella sp. from the Korean coastal waters

Euglenoids, the primary producers of fatty acids (FAs), are used in functional foods, feeds, and biofuels. Long-chain polyunsaturated FAs (LC-PUFAs) such as eicosapentaenoic acid and docosahexaenoic acid (DHA) are crucial for human health. The primary commercial source of LC-PUFA is fish; however, its heavy metal bioconcentration is concerning. Globally declining wild-harvested fish stocks is another recently recognized serious problem. Herein, the morphology, molecular phylogeny, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectroscopy, and FA compositions of an unspecified euglenoid strain KCTC 19016P isolated from the Korean coastal waters were examined. The vegetative cells were longitudinally spindle-shaped with a truncated apex and a tail-like extension at the anterior and posterior ends, respectively and had two unequal flagella. They had distinct red eyespots, numerous chloroplasts, and paramylon granules. Pellicular cell striations were easily observed using a scanning electron microscope. Phylogenetic analyses based on nuclear and chloroplast small-subunit ribosomal RNA sequences revealed that Eutreptiella sp. KCTC 19016P was nested within the Eutreptiella clade and was closely related to Eutreptiella marina (AY703209). Using the MALDI-TOF spectrum analysis, we differentiated between Eutreptiella sp. KCTC 19016P and the related NIES strains, thereby confirming their taxonomic similarities. Eutreptiella sp. KCTC 19016P growth was observed for 30 days; the maximum growth rate and doubling time was 0.50 ± 0.05 day−1 and 1.40 ± 0.15 day, respectively. Eutreptiella sp. KCTC 19016P had a relatively high monounsaturated FA percentage compared to the other species. The omega-3 FA content in Eutreptiella sp. KCTC 19016P was significantly higher than that of the other strains, as determined using ordinary one-way analysis of variance (P < 0.0001). Among the four euglenoids, Eutreptiella sp. KCTC 19016P had the highest α-linolenic acid and DHA contents. Thus, this new isolate could potentially be used in aquaculture and nutraceuticals without the risks associated with consuming fish.

Metal/metalloid bioconcentration dynamics in fish and the risk to human health due to water contamination with atmospheric particulate matter from a metallurgical industrial area

Settleable atmospheric particulate matter (SeAPM) containing a mixture of metals, including metallic nanoparticles, has increased throughout the world, and caused environmental and biota contamination. The metal bioconcentration pattern in Nile tilapia (Oreochromis niloticus) was evaluated during a 30-day exposure to 1 g L−1 SeAPM and assessed the human health risk from consuming fish fillets (muscle) based on the estimated daily intake (EDI). SeAPM was collected surrounding an iron ore processing and steel industrial complex in Vitória city (Espírito Santo, Brazil) area. Water samples were collected daily for physicochemical analyses, and every 3 days for multi-elemental analyses. Metal bioconcentrations were determined in the viscera and fillet of fish every 3 days. The elements B, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Rb, Sr, Ag, Cd, Pb, Hg, Ba, Bi, W, Ti, Zr, Y, La, Nb, and Ce were analyzed in SeAPM, water, and fish using inductively coupled plasma mass spectrometry. The metal concentration in SeAPM-contaminated water was higher than in control water. Most metals bioconcentrated preferentially in the fish viscera, except for the Hg and Rb, which bioconcentrated mostly in the fillet. The bioconcentration pattern was Fe > Al > Mn > Pb > V > La > Ce > Y > Ni > Se > As > W > Bi in the viscera; it was higher than the controls throughout the 30-day exposure. Ti, Zr, Nb, Rb, Cd, Hg, B, and Cr showed different bioconcentration patterns. The Zn, Cu, Sr, Sn, Ag, and Ta did not differ from controls. The differences in metal bioconcentration were attributed to diverse metal bioavailability in water and the dissimilar ways fish can cope with each metal, including inefficient excretion mechanisms. The EDI calculation indicated that the consumption of the studied fish is not safe for children, because the concentrations of As, La, Zr, and Hg exceed the World Health Organization's acceptable daily intake for these elements.

Bismuth exposure affects morpho-physiological performances and the ionomic profile in garden cress (Lepidium sativum L.) plants

Environmental pollution caused by heavy metals has long been considered a relevant threat to ecosystem survival and human health. The use of safer substitutes for the most toxic heavy metals in many industrial applications is discussed as a potential way to face this issue. In this regard, Bi has been proposed for replacing Pb in several production processes. However, few literature records reported on the effects of Bi on living organisms, particularly on plants. In this study, garden cress (Lepidium sativum L.) plants were exposed to different concentrations of Bi nitrate added to soil in growth chambers for 21 days. Results evidenced the toxic effect of Bi on shoot growth, regardless of the Bi nitrate concentration in the soil, paralleled by a similar reduction in the chlorophyll and carotenoid content, a decrease in the nitrogen balance index values, and an impairment of the photosynthetic machinery evaluated by chlorophyll fluorescence image analysis. The presence of Bi in the soil was shown to affect element accumulation in roots and translocation to shoots, with micronutrient content particularly reduced in the leaves of Bi-treated plants. A dose-dependent plant accumulation of Bi to metal concentration in the soil was observed, even if very low metal bioconcentration ability was highlighted. The reduced Bi translocation from roots to shoots in plants exposed to increasing Bi concentrations in the soil is discussed as a possible defense mechanism likely associated with the observed increase of anthocyan and flavonol contents and the activation of photoprotection mechanisms preventing higher damages to the photosynthetic apparatus.

Metalliferous atmospheric settleable particulate matter action on the fat snook fish (Centropomus parallelus): Metal bioaccumulation, antioxidant responses and histological changes in gills, hepatopancreas and kidneys.

Metallic smoke released by steel industries is constitute by a mixture of fine and gross particles containing metals, including the emerging ones, which sedimentation contaminates soil and aquatic ecosystems and put in risk the resident biota. This study determined the metal/metalloids in the atmospheric settleable particulate matter (SePM, particles >10 μm) from a metallurgical industrial area and evaluated metal bioconcentration, antioxidant responses, oxidative stress, and the histopathology in the gills, hepatopancreas and kidneys of fat snook fish (Centropomus parallelus) exposed to different concentrations of SePM (0.0, 0.01, 0.1 and 1.0 g L−1), for 96 h. From the 27 metals (Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Ba, La, Ce, W, Hg, Pb, Bi) analyzed, 18 were quantified in SePM and dissolved in seawater. Metal bioconcentrations differed among organs; Fe and Zn were the metals most bioconcentrated in all organs, Fe was higher in hepatopancreas and Zn > Fe > Sr > Al was higher in kidneys. The activity of superoxide dismutase (SOD) decreased in the gills; SOD, catalase (CAT) decreased, and glutathione peroxidase (GPx) increased in hepatopancreas and, CAT, glutathione-S-transferase (GST) and the level of glutathione (GSH) increased in kidneys. The unchanged levels of lipid peroxidation and oxidized protein in any organ indicate that the antioxidant responses were efficient to avoid oxidative stress. Organ lesion indices were higher in the gills > kidneys > hepatopancreas, being higher in fish exposed to 0.01 g L−1 SePM. All changes indicate a tissue-specific metal/metalloids bioconcentration, antioxidant and morphological responses that all together compromise fish health. Regulatory normative are needed to control the emission of these metalliferous PM to preserve the environment and biota.

Heavy metal exposure risk associated with ingestion of Oreochromis niloticus and Coptodon kottae harvested from a lacustrine ecosystem

Lacustrine ecosystems have not been widely assessed for heavy metal contamination and associated health risks; yet, they could be accumulating these contaminants to the detriment of aquatic organisms and communities relying on them for various aspects. The water quality index (WQI) and concentrations of heavy metals including As, Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, and Zn in water, sediment, Oreochromis niloticus, and in the endemic and endangered Coptodon kottae in Lake Barombi Kotto in Cameroon were determined to evaluate fish heavy metal bioaccumulation, and heavy metal exposure risk posed to communities consuming these fish species. The WQI of the lake was found to be excellent with heavy metal concentrations that were lower than what was obtained in the sediments and fish samples. Mean heavy metal concentrations in sediment ranged from 0.86 ± 0.03 mg/kg for Cd to 560.1 ± 11.15 mg/kg for Fe. In both fish species, Fe, Mn, and Cu had the highest concentrations. Though the heavy metal concentrations in the lake water were low, heavy metal bioconcentration factors for both fish species were very high ranging from 1.6 for Fe to 1568 for Mn. The concentration patterns of heavy metals in the organs of both fish species followed the order bones > gut > muscle. Consumption of these two fish species contributes less than 1.0% of the permissible tolerable daily intake (PTDI) and provisional tolerable weekly intake (PTWI) of these metals with lead (Pb) having the potential to exceed permissible exposure levels when high amounts of these fish are consumed by adults.

Coriander (Coriandrum sativum L.) in Combination with Organic Amendments and Arbuscular Mycorrhizal Inoculation: An Efficient Option for the Phytomanagement of Trace Elements-Polluted Soils.

The cultivation of coriander (Coriandrum sativum L.) destined for essential oils production was recently presented as an innovative and economically viable alternative for the phytomanagement of trace elements (TE)-polluted soils. However, Cd accumulation in shoots has proven to be an obstacle in the valorization of the distillation residues and the development of these phytotechnologies. The present study aimed to evaluate the effect of arbuscular mycorrhizal fungus (Funneliformis mosseae) inoculation and organic amendment application on the soil TE bioavailability and plant uptake, as well as on the soil quality and health improvement. The application of compost and sewage sludge improved the growth of coriander and Cd and Zn immobilization in soil, resulting in reduced Cd plant uptake. A synergistic effect of arbuscular mycorrhizal fungi (AMF) inoculation and organic amendments was observed in the decrease in the extractable soil Cd and Zn concentrations, but not in the Cd plant uptake. Despite a significant decrease in Cd accumulation in shoots, coriander retained its accumulative phenotype, with a metal bioconcentration factor close to 1. Furthermore, both the vegetation and the organic amendments improved the soil quality and health by increasing its microbial biomass, as estimated by phospholipid fatty acids, soil enzyme activities (dehydrogenase, phosphatase, β-glucosidase, and cellubiosidase), and the bacterial metabolic function and diversity. The findings demonstrate the potential of C. sativum, particularly in combination with organic amendments and AMF inoculation, for the phytomanagement of TE-polluted soils and soil quality and health improvement.

Phytoextraction of anthropogenic heavy metal contamination of the Blesbokspruit wetland: Potential of wetland macrophytes

Blesbokspruit wetland is one of the least conserved ecosystems in the Southern Africa region with active and latent threats of anthropogenic contamination stretching over decades of mining wastewater discharge, agricultural run-off, and a consistent influx of untreated sewage. This study provides an insight into the present-day spatial distribution of heavy metal contamination and the role of localised macrophytes in their phytoremediation. With exception of the first sampling point, the concentration of heavy metals in water samples throughout the wetland was within limits however findings from sediment samples were the inverse. The concentrations of Chromium and Nickel significantly exceeded both effect range low (ERL) and effect range medium (ERM) limits (250-430 mg/Kg and 73-151 mg/Kg respectively) as set out by international sediment quality guidelines. Emergent- Phragmites australis, Typha capensis, and free-flowing-Eichhornia crassipes macrophytes, which are naturally localised to the wetland were found to have varying bioaccumulation potential for different heavy metals; Bioconcentration of heavy metals in emergent macrophytes was relatively low especially for Nickel and Chromium compared to free-flowing macrophytes. E. crassipes accumulated significant amounts of the heavy metals with root concentrations of up to 17.23, 116.6, 330.5, and 342.9 mg/Kg for Arsenic, Lead, Nickel, and Chromium respectively. The emergent macrophytes were however found to bioconcentrate Arsenic up to 1.15 L/Kg (T. capensis) and 9.9 L/Kg (P. Australis) at sites 4 and 5 respectively. Findings with regards to bioconcentration especially of the E. crassipes, validate recommendations for the utilization of hyperaccumulating macrophytes for the natural recovery of these heavy metals towards alleviating the anthropogenic stress on this valuable ecosystem.

Phytoremediation and Bioconcentration of Mineral and Heavy metals in Zea mays Inter-planted with Striga hermonthica in Soils from Mechanic Village Wukari

Phytoremediation involves the use of plants to remediate contaminated sites. This study evaluates the effect of phytoremediation on mineral and heavy metal concentration in agricultural soil within the vicinity of mechanic village Wukari using Zea mays interplanted with Striga hermonthica (SMV-MS), Zea mays alone (SMV-M), Zea mays inter-planted with Striga hermonthica alongside the application of fertilizer (SMV-MSF) and Zea mays alone alongside fertilizer application (SMV-MF). The bioconcentration of mineral and heavy metal and their translocation factors from the root to shoot of maize plants were estimated using empirical models. The result reveals that the efficiency of phytoextraction of the mineral and heavy metals were within the range: P (3.12 – 44.71 %), K (16.89 – 96.32 %), Mg (0.013 – 94.12 %), Mn (2.31 – 99.98 %), Si (20.92 – 52.07 %), Zn (2.74 – 21.65 %), Pb (10.44 – 100 %), Cd (0.75 – 42.85 %), Fe (7.42 – 98.57 %) and Al (19.14 – 98.69 %) respectively. The mean root and shoot bioconcentration factors (BCFs) of K, Mg, Mn and Al were greater than one indicating higher accumulation of the elements in the root and shoot of the maize plants. The root BCF of the elements was generally in the order: Mn &gt; K &gt; Mg &gt; Cd &gt; S i &gt; Al &gt; P &gt; Fe &gt; Zn &gt; Pb while the shoot BCF was in the order: Mn &gt; K &gt; Mg &gt; Al &gt; Fe &gt; Cd &gt; S i &gt; P &gt; Zn &gt; Pb. The mean root to shoot translocation factors (TF) of P, Mn, Zn, Pb, Cd, Fe and Al were greater than one indicating effective translocation of the elements from the root to shoots. The translocation factors were generally in the order: Fe &gt; Al &gt; Pb &gt; Mn &gt; Zn &gt; P &gt; Cd &gt; Mg &gt; S i &gt; K.

Heavy metals in Lake Yanaka, Japan, an artificial retarding basin established for remediation of heavy metals contamination in the Watarase River

BackgroundThe Watarase Retarding Basin (WRB) involving Lake Yanaka was established for the sedimentation of the heavy metals contaminating the Watarase River in 1989. The Ashio Copper Mine poisoning (ACMP) incident that occurred from the late 19th century to the 1970s caused serious heavy metal contaminations along the Watarase River. Since stopping the mining activity in 1973, the heavy metal concentration in the water of the Watarase River significantly decreased. MethodsTo see the status of the heavy metal contaminations in Lake Yanaka, water, sediments, and Japanese river snails (marutanishi) were analyzed by using ICP-MS. ResultsThe concentration of As, Cd, Cu, Pb, and Zn in the waters exhibited a good correlation (r>0.96) with the concentration of those in the sediments. The concentration of As, Cd, and Pb in the water was under the Standards for Protecting Human Health in Japan (<10 µg/L, respectively). Whereas heavy metal concentrations in sediments of Lake Yanaka were not decreased and remained in the same range as those of the Watarase River reported in 1984. The concentrations of As and Zn in the sediments of Lake Yanaka were beyond the regulation standards (<15 mg/kg for As and <120 mg/kg for Zn). Heavy metals were highly concentrated in the shells, intestinal organs, and muscles of marutanishi snails. The bioconcentration of the heavy metals comparatively reflected the concentration in the sediments rather than those in the waters. In particular, the concentration of the heavy metals in the shells exhibited a good correlation (r>0.98) with those in the sediments. Heavy metals were more concentrated in the internal organs than shells and muscles. ConclusionSince the institution of Lake Yanaka in 1989, the water and sediments of Lake Yanaka were newly brought from the Watarase River. Although heavy metal concentrations in the sediment did not change, those in the water decreased. The function for precipitating heavy metals of WRB seems to work and Lake Yanaka works as a reservoir of over-flowed water and sediment, which include heavy metals, of WRB. This study reminded us it would take a long term to remediate the environment from heavy metal pollution.

New insights into trace metal speciation and interaction with phytoplankton in estuarine coastal waters

In coastal productive zones, phytoplankton activity may influence trace metal speciation and partitioning at short temporal scale. We coupled hourly in situ voltammetry quantification of the lead (Pb), cadmium (Cd), and copper (Cu) potentially bioavailable fractions, using an innovative submersible sensing probe (the TracMetal), to surface water sampling for the quantification of the targeted trace metals in the dissolved <0.2 μm and <0.02 μm fractions, suspended particles, and phytoplankton nets in the Gironde Estuary mouth. The in situ TracMetal monitoring reflected real-time dynamic Cd and Cu regeneration related to algal cells under post-bloom conditions as well as Pb remobilization due to photoreduction of colloids. The potentially bioavailable fraction consisted in 30, 30–50 and <10 % of the total dissolved fraction for Pb, Cd, and Cu, respectively, representing crucial ecotoxicological information. Metal bioconcentration factors using the dynamic fraction concentrations showed levels up to 107 for Cu in phytoplankton.