Cadmium and lead bioaccumulation in male chickens for high food concentrations

Cadmium and lead bioaccumulation in broilers fed on rations containing high concentrations of Cd and Pb was studied. The degree of bioaccumulation was assessed by using klark of concentration (Kc). It was established that the 100 and 200 fold increase of lead and cadmium in the ration resulted in their increase in the muscles, the bones and the liver, but the degree of bioaccumulation was considerably lower than the increase of both of the heavy elements in the ration indicated by the lower Kc. A conclusion was drawn that the organism possesses adaptation mechanisms for limitation of cadmium and lead bioaccumulation through these mechanisms are not efficient enough for high ration doses of both elements. High ration doses resulted in bioaccumulation exceeding the safe for humans concentrations of lead in the bones and of cadmium in the muscles (for doses 200 fold higher than the highest Bulgarian State standard 13426–77 permissible concentrations /HPC/) and in the liver for doses 100 fold higher than HPC.     

Pb、Cd及其复合污染对紫茎泽兰生长及吸收富集特征的影响

外来植物紫茎泽兰（Eupatorium adenophorum）入侵我国西南地区并造成了严重的生态灾难,通过研究Pb、Cd及其复合污染对紫茎泽兰生长及吸收富集特征的影响,有助于从生态学角度为紫茎泽兰的综合防控提供依据。采用模拟Pb、Cd污染土壤培养法研究了不同浓度Pb、Cd及其复合污染作用下紫茎泽兰的生长响应及重金属吸收、富集和迁移特征变化。结果表明：低浓度的Pb、Cd对紫茎泽兰的生长有促进作用,高浓度则表现出一定的抑制作用,生物量,株高,根长均明显减少。紫茎泽兰体内Pb、Cd吸收量与污染土壤具有良好的相关性,随处理浓度增加明显增大,极端浓度Pb、Cd胁迫下紫茎泽兰各器官Pb、Cd积累量与对照相比显著增加,1000 mg·kg-1处理时紫茎泽兰根、茎、叶的Pb质量分数均分别高达603.69、568.31、598.85 mg·kg-1;100 mg·kg-1 Cd处理时其根、茎、叶的Pb、Cd累积量依次为165.21、93.59、152.79 mg·kg-1。说明紫茎泽兰对Pb、Cd具有较好吸收累积及转运能力,可作为重金属污染地区的一种理想的修复植物。     

Roe and red deer as bioindicators of heavy metals contamination in north-western Poland

The present paper examines the degree of environmental contamination in areas covered by the Natura 2000 programme, located in north-western Poland, with selected heavy metals based on their concentration in target organs of roe and red deer. Lead, cadmium, copper, iron, and zinc concentrations were determined by inductively coupled plasma–atomic emission spectrometry. Residues of lead and cadmium were found in most of the analysed samples of roe and red deer organs The concentration of cadmium in the organs of the animals studied was much higher than that of lead. The median for Pb in liver and kidneys was 0.055 and 0.092 μg/g dry weight (d.w.) in roe deer, and 0.067 and 0.081 μg/g d.w. in red deer, respectively. The median for liver and kidney cadmium was 0.770 and 6.139 μg/g d.w. in roe deer, and 0.422 and 6.365 μg/g d.w. in red deer, respectively. Our study has demonstrated that this area is laden with lead and cadmium. This is evidenced by the fact that maximum permissible levels of these elements in the organs of red and roe deer, which were used as bioindicators of environmental contamination, were exceeded.     

Biosorption of lead and cadmium using marine algae

The use of algae (Ulva fasciata, green and Sargassum sp., brown) to reduce lead and cadmium levels from mono-metal solutions was investigated. The brown algae showed higher efficiency for the accumulation of lead (～1.5 times) and cadmium (～2 times) than green algae. The optimum pH value is found to be between 4 and 5.5. Regarding biomass concentration, an increase in metals percentage removal and a decrease in metal uptake capacity coincided with the increase in biomass concentration. All light metals (Ca, Mg and Na) showed a suppressive effect on biosorption capacity. The enhancement of biosorption in the case of NaOH was obvious. The biosorption process (65–90%) occurred within 3?min. Experimental data were in high agreement with the pseudo-second-order kinetic model and Freundlich model for lead and cadmium biosorption using different biosorbents. In the desorption study, 0.2?mol?L^?1 HCl recorded the best concentration for the elution of metals from the biomass. The biosorption capacity decreased over the four operational cycles for both lead and cadmium. Infrared analysis showed that amino, hydroxyl and carboxyl functional groups provide the major biosorption sites for metal binding. Use of the above-mentioned algae for cheap metal absorbance is considered as one water treatment criterion.     

Toxicity and bioaccumulation of cadmium and lead in Salvinia cucullata

The toxicity and accumulation of heavy metals, cadmium (Cd) and lead (Pb) in aquatic fern, Salvinia cucullata were studied. Plants were cultured in Hoagland's medium which was supplemented with 0.5,1,2, and 4 mg/l of Cd and 5, 10, and 40 mg/l of Pb and were separately harvested after 2,4,6, and 8 days. The toxicity symptoms of Cd and Pb to S. cucullata showed chlorosis on leaves. There were significant derceases in the relative growth, biomass productivity and total chlorophyll content when the exposure time and concentration were increased. The accumulation study showed the significant increases of both metals when the exposure time and concentration were increased. The roots of S. cucullata had higher Cd and Pb contents than leaves suggesting that the metals were bound to the root cells and were partially transported to the leaves.     

Baseline study on Cd,Cu and Pb concentrations in Atlantic neuston organisms

Neuston organisms were caught during two Atlantic expeditions (1982 and 1987) between 48°N and 40° S. About 1200 individuals from 19 taxa were analysed for cadmium, copper and lead. The distribution of metal concentrations was log-normal and thus best described by the median and the percentiles. Fourteen taxa with sample numbers larger than 20 were subjected to a logarithmic regression of weight vs metal concentration. The metal concentrations from populations with significant correlations were then weight-corrected: eight populations for lead, five for cadmium and four for copper. When grouped into ecological categories the pleuston organisms displayed significantly higher cadmium concentrations than the euneuston, which in turn had higher values than the pseudo-and/or facultative neuston. The relative deviation from the median was used in an averaging operation to obtain a broader spatial resolution of the neuston-bound metals, based on 16 taxa which were encountered at ten or more stations. The geographical distribution of cadmium and lead can be interpreted in light of chemical oceanographic knowledge and underlines the importance of organisms in the biogeochemical cycling of metals in the sea.     

Effects of a lead- and cadmium-resistant fungal strain on the absorption of heavy metals by Vetiveria zizanioides北大核心CSCD

A two-factor randomized complete block experiment was used to explore the remediation by a plant-microorganism combination on soils contaminated by lead (Pb) and cadmium (Cd). Factor A was the amount of fungi, for which four values were considered, namely, 0, 1, 3, and 5 g. Factor B was the level of contamination by lead and cadmium, for which six values were considered, namely, Cd0Pb0, Cd10Pb400, Cd20Pb600, Cd30Pb800, Cd50Pb1200, and Cd80Pb1800 (data in units of mg/ kg). The results showed that the resistant fungi promoted the growth of vetiver (Vetiveria zizanioides). At weights of 1, 3, and 5 g, the resistant fungi increased the biomass of vetiver by 41.9%, 74.9%, and 71.7% respectively. The resistant fungi stimulated the absorption of lead and cadmium by both the aerial and underground parts of vetiver. In the presence of 80 mg/kg of Cd2+ and 1 800 mg/kg of Pb2+, the contents of lead in the aerial parts of vetiver were increased by 120.6%, 265.4%, and 242.9%, while the lead content in the underground parts were increased by 110.3%, 278.2%, and 266.2%, after the addition of 1 g, 3 g, and 5 g of fungi, respectively. The content of cadmium in the aerial parts increased by 113.2%, 238.3%, and 217.3%, while the content of cadmium in the underground parts increased by 103.1%, 298.8%, and 274.4%, after the addition of 1 g, 3 g, and 5 g of fungi, respectively. The addition of fungi strengthened the effect of V. zizanioides to remediate soils contaminated by lead and cadmium, and the remediation after the addition of 3 g of fungi was better than that after treatment with 1 g and 5 g of fungi. The combination of resistant fungi and the heavy metal enrichment plant, vetiver, under different concentrations of lead and cadmium showed that the fungi had a significant effect on the remediation of soils contaminated by lead and cadmium. © 2018 Science Press. All rights reserved.     

Accumulation and elimination of cadmium and lead in juvenile milkfish during sublethal exposure

Pollution of aquatic environments by trace metals is a worldwide environmental problem. Metal pollutants are increasingly being released into the environment as a result of industrialization. In this study, the bioaccumulation of cadmium and lead in young juvenile milkfish liver (Chanos chanos) was investigated after exposure to three sublethal concentration of each pollutants (1/20, 1/10, and 1/5 LC₅₀ of 96-h LC₅₀) for acute time 12, 24, and 96 h and subchronically for 7, 14, and 21 days. Cadmium and lead accumulation in liver increased with the exposure period and concentrations of pollutant. Compared to controls, the uptake of cadmium is much higher than that of lead. Accumulation factors showed an increase with exposure time and for lead an inverse relationship between accumulation factor and exposure concentration. The elimination of the two pollutants during the 30 days depuration was investigated after 30 days depuration time. During this phase, cadmium and lead concentrations decreased.     

Evaluation of heavy metal contamination in Phaeozem of northeast China

Surface and profile Phaeozem soil samples from 31 locations affected by various anthropogenic activities such as mining, chemical manufacturing, traffic emission and pesticide application were collected in Heilongjiang Province and Jilin Province, northeast China. The range of total concentrations of four heavy metals Cd, Pb, Cu and Zn in the soil was 0.011–3.137, 10.31–62.34, 9.74–51.21 and 39.54–247.59 mg kg⁻¹, respectively, determined using the acidic digestion procedure. Four methods including single contamination evaluation, background concentration comparison, surface/subsurface concentration comparison and exchangeable fraction evaluation were used to evaluate the extent of metal contamination in Phaeozem. The results indicated that different activities increased the concentrations of the heavy metals in surface soils, where high concentrations of cadmium and lead were found close to chemical plants and in the suburbs of the investigated cities. The four methods showed a general trend of increased soil contamination with heavy metals. Cadmium was of the most concern compared with the other contaminated elements in the study area, due to the long-term phosphatic fertilizer utilization and industrial activities. The proper evaluation method for cadmium contamination was the background concentration comparison, while for zinc and copper was the single contaminative index evaluation. Cadmium and lead could be the potential environmental risk in the Phaeozem area based on the different evaluations.     

Trace Metal Studies on the Starfish Asterias rubens L. From the Western Baltic Sea

In 1984, 115 samples of the starfish Asterias rubens L. collected in the south-eastern part of Cadet Trench (Mecklenburg Bay/Western Baltic Sea) were analyzed for their contents of a few major (calcium, magnesium) and trace elements (cadmium, copper, iron, mercury, manganese, nickel, lead, selenium and zinc). Distinct differences were found between starfish from different stations, and these are attributed to the composition of the sediments acting as a substrate for their prey (mussels, snails). Except for cadmium, the concentrations of the elements studied all correlated negatively with the diameter and weight of the starfish.

Parallel analyses of starfish arms and the central discs of the same animals showed that iron, zinc, copper and mercury levels were 16 to 30% higher, and selenium, manganese, magnesium, calcium and lead were 4 to 9% higher in the arms. Cadmium concentrations were 20% higher in the central discs than in the arms.

Stock estimations (about 52,000 tons fresh weight) show that starfish play a significant role in the benthic ecosystem of the western Baltic Sea. They can consume up to 200,000 tons of mussels and clams (Mytilus edulis, Macoma baltica) a year and may therefore represent a notable factor in the trace metal balance of the region.     

Modelling the kinetics and equilibrium properties of cadmium biosorption by river green alga and water hyacinth weed

Cadmium biosorption properties of non-living, dried river green alga from a river source, and water hyacinth weed, Eichhornia crassipes from a lake in Zimbabwe have been investigated. The cadmium uptake was found to depend on initial pH, uptake being apparently minimal at low pH values and increasing with an increase in pH. Cadmium biosorption kinetics by both samples is fast, with 80% of total uptake occurring within 60?min. The effect of initial solution pH and initial cadmium concentration on cadmium biosorption from a cadmium solution has been studied. The data for algal biomass fitted the Langmuir monolayer adsorption isotherm, while the biosorption of the metal by water hyacinth weed fitted the Freundlich adsorption isotherm with 1/n values all less than 1. Maximum metal uptake capacities were recorded using 0.35?g of biomass and a 250?mg?L^?1 cadmium solution at pH 6.5 and at 25°C and these were about 85 and 50?mg?L^?1 for water hyacinth weed and green alga, respectively, showing that water hyacinth weed offered a greater potential for cadmium uptake. The absorption was described by pseudo-second order rate model and the rate constant and equilibrium sorption capacity are reported.     

The prevalence of heavy metals in Cladophora glomerata L. from Farahabad Region of Caspian Sea – Iran

The presence of toxic heavy metals in the environment is considered as a risk factor for adverse human and environmental health effects. Farahabad Region is a tourist center in the southern coast of Caspian Sea in Mazandaran Province of Iran. Environmental monitoring of this site is important for public health for individuals visiting and residing in this region. Although numerous biomonitoring data are available globally, very few if any apparent investigations have been conducted in this region. In this study, concentration of three heavy metals chromium (Cr), lead (Pb), and cadmium (Cd) was determined for one year in Cladophora glomerata, the predominant macroalga species present in this region. Detection of heavy metals was performed with atomic absorption spectrophotometer using standard methods. Results showed that the range of Cr metal in various algal samples was 29–55 ppm/g dry weight. The levels of Pb in algal samples (Cladophora) ranged from 2 to 8 ppm/g dry weight. The Cd concentrations in C. glomerata biomass ranged from 1.5 to 8.2 ppm/g dry biomass. In view of potential threats of such high metal concentrations in coastal waters and in algal tissues, it is necessary to adopt conservation measures to ensure public health safety.     

Tessaria absinthioides: a possible bio‐monitor for Cd,Pb, and Cu,in the middle and lower basin of the loa river,North Chile

Some ecotoxic metals such as Cd, Pb, and Cu in Tessaria absinthioides were quantified to study its possible use as a bio‐indicator and/or bio‐monitor of these metals. This plant was chosen for its abundance in the area under study, along Chile and even in southern Latin America. For Cd, Pb, and Cu in all three parts of the plant (leaves, stems and roots) a different concentration pattern in each sampling areas was observed. In sampling areas Coya Sur and La Cascada copper and cadmium concentration decrease in order: leaves > roots > stems. In samples collected in Xalquincha the lowest concentrations of Cd and Pb were observed in stems. A maximum of cadmium concentration (9ug/gd.w. in leaves) was found in samples from La Cascada, a inflow to river Loa in Calama. High concentrations of lead were found in roots and leaves. Collected data demonstrate that the main pathway for cadmium is from ground water via roots into the plant. Some data obtained for lead and copper indicate that the influence of dust particles adsorbed on leaves and stems can be higher than uptake from ground water.     

Effects of cadmium on metallothionein and histology in gills of tilapia (Oreochromis niloticus) at different salinities

The objectives of this study were to evaluate the effects of sublethal cadmium concentrations on the levels of cadmium, metallothionein (MT) and histological changes in gills of East Java strain tilapia (Oreochromis niloticus) at different salinity levels. The levels of cadmium in control gills were not significantly different at 0, 5 and 10 practical salinity unit (PSU). The cadmium concentrations in gills of cadmium-exposed fish were significantly higher at 0 PSU than at 5, 10 and 15 PSU. The MT concentrations in control gills were not significantly different at 0, 5, and 10 PSU. The MT concentrations of cadmium-exposed fish were significantly higher than those in respective control groups at 0, 5 and 10 PSU. Significant gill damage occurred in fish exposed to cadmium at lower salinity. The epithelial lifting was noted at gills of fish exposed to 2.5 mg/L of cadmium at 0 PSU, and telangiectasis was observed at gills exposed to 5 mg/L of cadmium at 0 PSU. The level of gill damage decreased with increasing salinity of media. The increased MT and histological changes in gills of our findings could be a protective response of animals to toxic effect of cadmium.     

Soil and plant concentrations of cadmium and zinc in the vicinity of a smelter

Cadmium, zinc and lead concentrations in soils and plants near a smelter at Avonmouth are reported for samples collected in May 1979 and in May 1980. The total metal soil concentrations fall as distance from the smelter increases and decrease rapidly with depth for cadmium and zinc. The concentrations of these two metals are highly correlated at all depths. Near the smelter, where the carbon content and pH values of the soils are lowest, almost all the cadmium, as measured by EDTA extraction, is available. Concentration of metals in plants also decrease with distance from the smelter, with concentrations being lower in samples collected in 1980. This is possibly due to a seasonal variation in biomass, producing a dilution effect. We conclude that uptake of cadmium and that of zinc by grass species have different relationships to the carbon content of the soil.     

铜、镉、敌敌畏和甲胺磷对南美白对虾的亚急性毒性作用

在恒温和充气条件下,研究了重金属(铜、镉)和有机磷农药(敌敌畏、甲胺磷)对南美白对虾的亚急性毒性作用及对虾体胆碱酯酶的影响.结果表明:南美白对虾幼虾在各浓度重金属(铜、镉)和有机磷农药(敌敌畏、甲胺磷)试液中经过60d的亚急性中毒试验,除铜在低浓度促进生长外,其他各组体长、体重及蜕皮次数均小于对照组,且随毒物浓度的增加而逐渐降低;有机磷农药对南美白对虾体内胆碱酯酶具有显著影响,虾体内胆碱酯酶含量随水体中有机磷农药浓度的升高而显著降低;重金属对胆碱酯酶也有一定影响,胆碱酯酶随重金属离子浓度升高也有逐渐降低的趋势,但重金属对胆碱酯酶的影响效果没有有机磷农药显著.     

The common mussel Mytilus edulis as an indicator of pollution by zinc,cadmium, lead and copper. I. Effects of environmental variables on uptake of metals

The net uptake of zinc, cadmium, lead and copper by the common mussel Mytilus edulis (L.) exposed to different conditions was investigated with a view to using this species as an indicator of contamination of the marine environment by these metals. The variables studied were season, position of the mussel in the water column, water salinity, water temperature, and the simultaneous presence of all four metals. Each of these 5 variables affected the net uptake of some or all of the metals studied under some conditions. Seasonal variation in concentrations of zinc, cadmium and copper was found in samples collected at three separate locations. The relationship of seasonal variation to tissue weight and absorption route of the metals is discussed. Near to freshwater inputs of trace metals, the concentrations of zinc, cadmium and lead in mussels were found to vary according to the depth at which the mussels were collected; in summer when freshwater run-off is less, this effect was absent. Low salinities did not affect the net uptake of zinc by mussels, but increased the net uptake of cadmium and decreased that of lead. Low temperatures had no effect on the net uptake of zinc or lead; the net uptake of cadmium was unaffected by low temperatures at high salinities but was decreased by low temperatures at low salinities. The presence of the other metals had no effect on the individual net uptake of either zinc, cadmium or lead. A sampling programme was devised to eliminate the effects of these environmental variables and to allow the use of M. edulis as an indicator of zinc, cadmium and lead in marine and estuarine environments. In contrast to the other metals, the net uptake of copper by the mussel was extremely erratic, and was affected by salinity and temperature changes and by the presence of the other metals and changes in their relative concentrations. The effects of other metals on the net uptake of copper cannot be easily eliminated or allowed for; it is, therefore, suggested that the mussel should not be used as an indicator of copper in the marine environment.     

Vehicle-Induced Lead and Cadmium Contamination of Roadside Soil and Plants in Italy

Lead and cadmium concentrations in spontaneous vegetation and in soil sampled at various distances (0–208 m) from several motorways throughout Italy were measured. Lead and cadmium concentrations appear to be correlated to distance from the motorway and to traffic levels. A comparison with data from a remote and unpolluted site shows that foliar lead concentrations can be up to 40 times higher, and foliar cadmium concentrations up to 3 times higher. Plants behave differently in their accumulation of lead and cadmium; conifers present the highest levels. Also the various receptors and compartments of the roadside ecosystem differ in their accumulation of lead and cadmium; soil and bark have consistently higher concentrations, while the leaves and twigs of trees have consistently lower levels. the data recorded by ad hoc introduced bio-accumulating plants (Lolium multiflorum L.) are consistent with those of the spontaneous vegetation. the concentrations of both lead and cadmium in Lolium vary from June to November, following in part the fluctuation in traffic density.     

The effect of chelating agents on the uptake and accumulation of cadmium by Mytilus edulis

The uptake, storage and excretion of cadmium by the common mussel Mytilus edulis (L.) has been studied at sub-lethal concentrations using the radioactive isotope ^115mCd as a marker. After an initial lag period, the uptake at low concentrations in sea water is linear with time and directly proportional to the sea water concentration, with a maximum concentration factor of 165 at 0.7 g Cd/ml sea water. A decrease occurs at higher concentrations indicating saturation of the available binding capacity. Prior complexation of the cadmium with either EDTA, humic and alginic acids or pectin doubles both the rate of accumulation and the final tissue concentrations (order: kidneyviscera>gillsmantle>muscle) and eliminates the lag period, suggesting that ionic cadmium must first be complexed before uptake can occur. A mechanism for this effect, which may involve thionein, is described. The rate of excretion of cadmium is 18 times slower than that of uptake, with the major route via the kidney but not via the byssal threads as with particulate iron. The need to detoxify and store cadmium by an immobilization mechanism is a consequence of this slower rate of elimination.     

Trace Metal Studies on the Starfish Asterias rubens L. From the Western Baltic Sea

In 1984, 115 samples of the starfish Asterias rubens L. collected in the south-eastern part of Cadet Trench (Mecklenburg Bay/Western Baltic Sea) were analyzed for their contents of a few major (calcium, magnesium) and trace elements (cadmium, copper, iron, mercury, manganese, nickel, lead, selenium and zinc). Distinct differences were found between starfish from different stations, and these are attributed to the composition of the sediments acting as a substrate for their prey (mussels, snails). Except for cadmium, the concentrations of the elements studied all correlated negatively with the diameter and weight of the starfish.

Parallel analyses of starfish arms and the central discs of the same animals showed that iron, zinc, copper and mercury levels were 16 to 30% higher, and selenium, manganese, magnesium, calcium and lead were 4 to 9% higher in the arms. Cadmium concentrations were 20% higher in the central discs than in the arms.

Stock estimations (about 52,000 tons fresh weight) show that starfish play a significant role in the benthic ecosystem of the western Baltic Sea. They can consume up to 200,000 tons of mussels and clams (Mytilus edulis, Macoma baltica) a year and may therefore represent a notable factor in the trace metal balance of the region.