Comparison of tin and lead toxic action on erythropoietic system in blood and bone marrow of rabbits

The aim of this work was to assess and compare morphological changes in blood and bone marrow of rabbits afterper os (po) or intraperitoneal (ip) administration of equimolar doses of tin or lead. The experiment was performed on female rabbits that were divided into four groups of six animals each, and received stannous chloride SnCl₂×2 H₂O (Merck) or lead acetate Pb(CH₃COO)₂ (POCh Gliwice) in equimolar doses (ip—17/uM/kg) orper os (po—85/uM/kg). Group I was administered SnCl₂ ip at the dose of 2 mg Sn/kg every day for 3 mo, group II Pb(CH₃COO)₂ ip at a dose of 3.5 mg Pb/kg every day for 3 wk, group III po SnCl₂ (10 mg Sn/kg), and group IV po Pb(CH₃COO)₂ (17.5 mg Pb/kg), both for 4 mo. The morphological factors hemoglobin (Hb), hematocrit (Ht), erythrocyte (Ercs), and reticulocyte counts, MCV, MCH, MCHC, and erythropoietic system in bone marrow aspirates with sideroblast count, iron concentration, TIBC, and SI were estimated. Tin caused hemolytic anemia depending on abnormal iron utilization. After ip administration of tin, anemia was observed during the whole time of the study, whereas after po exposure, transient anemia was noticed. It has been proven that the mechanism of toxic action of tin on hematopoietic system is similar to the toxic effect of lead.     

Immunotoxicological investigation of subacute combined exposure with low doses of Pb, Hg and Cd in rats

Detectable interactions between NOEL (No Observed Effect Level) doses of Pb, Hg and Cd in general toxicological, hematological, and immune function parameters were investigated. The metals (Pb-acetate, 20 mg/kg; HgCl2, 0.40 mg/kg; CdCl2, 1.61 mg/kg) were combined. First, the rats received the combination Pb + Hg + Cd for 4 weeks per os. Significant difference vs. control was found only in the weight of lung and popliteal lymph node (PLN). The Pb + Hg and Pb + Cd combinations significantly decreased the PLN to 100 g body weight and PLN to brain weight ratio, and Pb+Hg also decreased the relative adrenal weight. After 12 weeks treatment with the same doses, effects on the thymus, kidney, and adrenal weights in the Pb + Hg, and thymus weight in the Pb + Cd, combination were seen. Pb + Cd also affected the white and red blood cell count and hematocrit. Combined with Hg or Cd, NOEL dose Pb showed toxicity, indicating that exposure limits may be inefficient in combined exposure situations.     

Influence of dietary supplementation with thiamine on lead intoxication in rats

The influence of dietary supplementation with thiamine on lead (Pb) contents in blood and tissues, blood δ-aminolevulinic acid dehydratase (δ-ALAD) activity, and urinary excretion of δ-aminolevulinic acid (δ-ALA) was evaluated in male Sprague-Dawley rats. Groups of randomly selected animals were given a thiamine-deficient diet, a diet containing normal thiamine (20 mg/kg), or a thiamine-supplemented diet (50 mg/kg), along with control drinking water or water containing 100 ppm Pb, for 4 mo. Animals fed the thiamine-supplemented diet (50 mg/kg) and Pb showed decreased urinary excretion of δ-ALA and a decreased inhibition of δ-ALAD activity in blood compared to those given Pb with normal thiamine diet. The liver, kidney, and blood of rats receiving supplemental thiamine also contained significantly less Pb than the other two treatment groups given Pb-containing water. The protective effect of thiamine against Pb toxicity may be attributed to its interference with retention of the metal in body tissue, possibly resulting from the formation of excretable thiamine-lead complexes.     

The dynamics of [3H]-cholesterol incorporation into the liver and aortic tissue of guinea pigs on long-term ethanol administration]

The effect of ethanol administration to guinea pigs (4 g/kg, per os) on the dynamics of [3H]-cholesterol incorporation into the liver and aorta tissues was studied for 3 months. It has been discovered that specific radioactivity of the control animals linearly increased during 24 hours in the blood serum. Ethanol reduced it as compared with the control only 0.5 h after a label has been introduced. Cholesterol renovation in the liver remained unchanged under the prolonged effect of ethanol. In the aorta the ethanol effect was characterized by a decrease of [3H]-cholesterol specific radioactivity 0.5 h after its administration. However, in this case the ratio of aorta/blood serum radioactivity increased. A day after the labelled cholesterol administration to alcoholized animals the radioactivity calculated per 1 mg of cholesterol and per unit of tissue weight and referred to the blood serum radioactivity was lower as compared to the control level.     

Studies of Zn, Mg, Cu, Ca and Fe in cadmium poisoned toads before and after treatment with EDTA

Zn, Mg, Cu, Ca and Fe were determined spectrophotometrically in liver, kidneys, muscle, spleen and blood of Bufo regularis after a single i.m. injection of 6.2 mg Cd/kg (which represents the 96 hr LD50) alone or in combination with 40 mg EDTA/kg (the minimal EDTA concentration causing 100% survival over that period). Cadmium administration caused recognizable effects on the essential metals levels in different tissues and organs. In the majority of the tissues and organs studied, zinc and copper concentrations returned to their normal ranges in animals that received both cadmium and EDTA. In contrast, magnesium, calcium and iron contents not only returned back to their control values but also exceeded them.     

Effects of excess dietary selenite on lead toxicity in sheep

The hypothesis that excess dietary selenite ameliorates lead (Pb) toxicosis in domestic sheep was tested. Twenty 6–8-yr-old ewes fed alfalfa pellets were assigned to the following treatments: (1) control; (2) 9.8 mg Pb/kg body weight (b.w.)/d as PbCO₃; (3) 3 mg Se/animal/d as Na₂SeO₃·5H₂O; or (4) a combination of treatments 2 and 3. The gelatin-encapsulated salts were given orally. The study was terminated on d 104, by which time three animals in the Pb group and all five animals in the Pb+Se group had died. All remaining animals were slaughtered on d 104. Lead and Se concentrations were determined in six biweekly-collected blood samples and in soft tissues and bone. Sheep on the control and Se treatments had similar feed intakes, body weights, and tissue Pb levels. Those in the Pb+Se group had lower feed intake, but higher blood Pb values compared with the Pb group. Feeding either element increased (P<0.05) the concentration of that element in blood, kidney, liver, spleen, and bone. Muscle-Pb concentrations were not affected (P<0.05) by treatment. Selenium concentrations in kidney, liver, and muscle were greater (P<0.05), whereas those in heart were less (P<0.05) for the Pb+Se group than for the Se Group. Clinical signs associated with Pb toxicosis noted in other animals were not observed in the poisoned sheep in this study. Selenite did not protect sheep against Pb toxicity and likely served as a synergistic factor.     

环境重金属污染物的生物有效性

利用生态系统研究了白银有色金属冶炼矿区周围环境中重金属的分布及生物有效性。结果表明 ,工厂在冶炼过程中已造成 Pb、Cd、Cu、Zn对周围环境不同程度的污染 ,其含量与距工厂的距离呈负相关 ;重金属在各种生物体内均有不同程度的吸收和累积 ,其吸收累积量随重金属和生物种类的不同而有差异 ;土壤的污染 ,使农作物和牧草中 Pb、Cd含量超过动物的最大耐受量和中毒的临界值 ;动物研究发现 ,肾脏、骨骼和肝脏是机体内重金属蓄积的主要器官。因此 ,放牧动物可作为环境重金属污染状况的标识 ,对评价重金属环境污染对当地人群的危害也有重要意义     

Effects of copper aspirinate and aspirin on tissue copper,zinc, and iron concentrations following chronic oral treatment in the adjuvant arthritic rat

Concentrations of copper, zinc, and iron were analyzed and compared in a number of tissues of adjuvant arthritic rats following 22 d of chronic treatment (per os) with either vehicle, aspirin or copper aspirinate, at doses of 100 mg/kg, 200 mg/kg, or 400 mg/kg. Such chronic treatment resulted in a negative balance in copper, zinc, and iron in many tissues. Among the tissues examined, liver and kidney exhibited the greatest changes in metal concentrations; brain and skeletal muscle exhibited the least. Arthritis-induced changes in the concentrations of all three metals in the liver were reversed upon treatment with aspirin. Treatment with copper aspirinate, on the other hand, resulted in an extremely high accumulation of copper in the liver. Arthritis-induced changes in copper, zinc, and iron concentrations in the pancreas and copper concentration in the plasma were generally not reversed upon treatment with either aspirin or copper aspirinate. Among the three metals examined, the degree of change observed as a result of drug treatments was greatest for iron and least for zinc. Finally, it appeared that the effects of aspirin and copper aspirinate on tissue metal concentrations were independent of the antiarthritic effects of these compounds.     

Evaluation of dosages and routes of administration of tramadol analgesia in rats using hot-plate and tail-flick tests

Tramadol is an opioid-like analgesic with relatively mild side effects. Because it is inexpensive and is not classified as a controlled substance by the US federal government, the authors wanted to evaluate its applicability as a practical and effective analgesic in male Sprague Dawley rats. They measured the efficacy of four dosages (4, 12.5, 25 or 50 mg tramadol per kg body weight) and three routes of administration (per os (p.o.) in a flavored gelatin cube, subcutaneous (s.c.) or intraperitoneal (i.p.)) using the hot-plate test and the tail-flick test, which were carried out 1 week apart. Rats that were dosed p.o. were given flavored gelatin cubes without tramadol on the 2 d before testing to help them become acclimated to the gelatin, in an effort to increase the likelihood that they would consume the gelatin on the testing day. Results from the hot-plate and tail-flick tests for rats that were given tramadol p.o. were similar before and after administration, regardless of tramadol dosage, suggesting that this route of administration was not effective. The s.c. route of administration was effective at dosages of 25 mg and 50 mg tramadol per kg body weight, although these dosages also resulted in sedation and skin lesions. The i.p. route of administration was also effective at dosages of 12.5 mg, 25 mg and 50 mg tramadol per kg body weight, though sedation was observed at dosages of 25 mg and 50 mg per kg body weight. Intraperitoneal administration of 12.5 mg tramadol per kg body weight had no notable side effects, and the authors plan to further study this dosage and route of administration in a rodent surgical model of pain.     

Concentrations of Lead,Cadmium, and Mercury in Halfbeaks (Hyporhampus affinis) from the East Java Coast,Indonesia and Human Health Hazard

The objectives of this study were to measure the levels of lead, cadmium, and mercury in the muscle tissues of halfbeaks (Hyporhampus affinis) captured at five stations along the East Java coast, Indonesia. This fish is one of the important species and consumed by local people as a cheap source of protein. We evaluated the hazard level posed by the metals in relation to the maximum residual limit for human consumption and to estimate the weekly intake and compare it with the provisional tolerable weekly intake (PTWI). The Pb, Cd, and Hg concentrations in fish at all stations ranged from 0.006 to 0.023 mg/kg, 0.007 to 0.024 mg/kg, and 0.047 to 0.055 mg/kg wet weight, respectively. All samples of halfbeaks collected from this area appear to be safe for human consumption because their metals’ levels are below the permissible limit for human consumption and the maximum weekly intakes are below the recommended values of PTWI.     

Effect of lead in water on the absorption of copper, iron, manganese and zinc by sheep (Ovis aries) infected with sheep tapeworm (Moniezia expansa)

The sheep tapeworm (Moniezia expansa) and its host Ovis aries were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) for their copper, iron, manganese, zinc and lead levels. Element concentrations in cestode parasites were compared to those in various organs (liver, kidney, and muscle) of sheep. Tapeworms in the small intestine of sheep that were administered 2g of Pb(CH(3)COO)(2) per os daily (7 days) had significantly higher lead concentrations than sheep tissues. Cu levels significantly increased after Pb administration in sheep muscle and sheep tapeworms. Contrarily, Zn content significantly decreased in sheep muscle, but significantly increased in sheep tapeworms. However, Mn content significantly decreased after Pb administration in sheep tapeworms. Furthermore, Fe content significantly decreased after Pb administration in sheep liver and kidneys.     

Tissue distribution and urinary excretion of essential elements in rats orally exposed to aluminum chloride

The purpose of this study was to determine disorders in the metabolism of the essential elements (Ca, Fe, Cu, and Zn) in some tissues of rats, as well as to detect the dynamics of urinary excretion of these metals after oral administration of 20 mgAl/kg every day for 8 wk. The elements were determined in brain, kidneys, blood, and urine of the animals in 1st, 2nd, 3rd, 4th, and 8th wk after the exposure to AlCl₃. After the 1st wk of aluminium administration, we observed increase of Ca and a decrease of Fe in blood. In brain Ca, Fe, and Cu concentrations were significantly higher in Al-treated rats than in controls after 8-wk exposure. The concentration changes of the essential metals in the tissue were accompanied by increase of the Ca, Fe, and Zn urinary excretion. We assume that the increase in urinary excretion of Ca and the decrease of Fe in the blood may be sensitive indicators of oral aluminium administration.     

Use of the IEUBK Model for Determination of Exposure Routes in View of Site Remediation

The Integrated Exposure Uptake Biokinetic (IEUBK) model is frequently used to estimate blood lead concentrations of children exposed to lead. Simulations with the IEUBK model were run to estimate the blood lead concentration in children living in the vicinity of a non-ferrous plant, situated in Hoboken, Belgium. Concentrations in soil ranged from 59–2425 mg Pb/kg dm, average concentrations in house dust ranged from 234–73394 mg Pb/kg dm. Measured blood lead concentrations in children aged 2–7 years were between 3 and 35 μ g/dl. Exposure sources were indoor dust in the house and the school, outdoor dust and soil in the home surrounding and at the school's playground, and suspended dust in the air. Soil ingestion values and lead exposure from food were changed to Flemish values. The model was able to predict the measured blood lead concentrations adequately except for the lowest exposure group. Predictions showed a systematic overestimation. Analysis of the data revealed that the neighbourhood's school is an important source of exposure to lead; indoor house dust dominates exposure for children going to school outside the area, because of the high concentrations of lead in indoor dust (3 to 5 times higher than in outdoor soil).     

N-acetylcysteine exposure on lead-induced lipid peroxidative damage and oxidative defense system in brain regions of rats

Lead (Pb) is known to disrupt the pro-oxidant/antioxidant balance of tissues, which leads to biochemical and physiological dysfunction. Oxidative stress is considered a possible molecular mechanism involved in Pb neurotoxicity. Considering the vulnerability of the brain to oxidative stress under Pb neurotoxicity, this study investigated the effects of exposure of the thiol antioxidant N-acetylcysteine (NAC) on lead-induced oxidative damage and lipid peroxidation in brain regions of the rat. Wister strain rats were exposed to lead in the form of lead acetate (20 mg/kg body wt/d) for a period of 2 wk and the effects of NAC on lead-induced neurotoxicity in rat brain regions were assessed by postadministration of NAC (160 mg/kg body wt/d) for a period of 3 wk. The lipid peroxidation byproduct, malondialdehyde (MDA) increased following lead exposure in both of the regions, and the antioxidant capacities of the cell in terms of the activity of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) was diminished. Following NAC treatment, lead-induced lipid peroxidation decreased and antioxidant enzyme activities improved, with CAT showing enhancement in the cerebral region only and SOD showing enhancements in the cerebellar region. Our result suggests that thiol-antioxidant supplementation following Pb exposure might enhance the reductive status of brain regions by arresting the lipid peroxidative damage in brain regions.     

Effects of Plant Residue and Salinity on Fractions of Cadmium and Lead in Three Soils

Bioavailability and mobility of heavy metals (HMs) in soils are determined by their partitioning between solution and solid-phase and their further redistribution among solid-phase components. A study was undertaken to determine the effects of organic matter (OM) and salinity on cadmium (Cd) and lead (Pb) distribution among soil fractions. Three agricultural soils were treated with 20 mg Cd/kg as Cd (NO₃)₂·4H₂O, 150 mg Pb/kg as Pb (NO₃)₂, 20 g/kg alfalfa powder, and 50 mmol/kg of NaCl, and then incubated at 60% water holding capacity (60% WHC) and constant temperature (25°C) for 12 weeks. Various fractions of Cd and Pb were extracted from the soils after 2 and 12 w of incubation using a sequential extraction technique. Results showed that in the early stage of incubation (2 w), added Pb were found mainly in the specifically sorbed (SS) and amorphous Fe oxides (AFeO) fractions and added Cd found in SS and Mn oxides (MnO) fractions. Addition of 2% OM decreased the exchangeable (EXC) Pb fraction almost in all soils, whereas it had a different effect on the EXC Cd fraction depending on soil pH. Addition of NaCl increased the EXC Cd fraction in two soils, but it did not alter Pb fractions. At the end of the incubation period, Pb decreased in the EXC and MnO fractions except in the neutral soil and Cd decreased mainly in the SS fraction.     

A Fragrant Solution to Soil Remediation

The ability of scented geraniums (Pelargonium sp. ‘Frensham’) plants to tolerate, uptake, and accumulate lead was assessed compared with two well-established metal accumulators, Indian mustard (Brassica juncea) and sunflower (Helianthus annuus), under greenhouse conditions. The efficiency of the photosynthetic apparatus and the number and size of active photosynthetic reaction centers (expressed as chlorophyll a fluorescence ratios of variable fluorescence to maximal fluorescence [Fv/Fm] and variable fluorescence to unquenchable portion of fluorescence [Fv/Fo], respectively) were affected to varying degrees at all metal concentrations in all the plants tested. Lead exposure did not significantly affect the efficiency of photosystem II activity or the number and size of the photosynthetic reaction centers in scented geraniums, but the ratios decreased significantly in Indian mustard and sunflower plants following lead exposure. In addition to tolerating high levels of lead, the scented geraniums accumulated in excess of 3000 mg of lead per kg DW of shoot and above 60,000 mg of lead per kg DW of root tissue. Additionally, scented geraniums exposed to a mixture of metals (lead + cadmium + nickel) had the ability to uptake in excess of 4.72% Pb + 0.44% Cd + 0.52% Ni per kg of root DW, as well as 0.17% Pb + 0.07% Cd + 0.14% Ni per kg of shoot DW within 14 d, indicated the potential for existence of more than one functional tolerance and metal uptake mechanism(s). The cellular localization of lead was assessed using transmission electron microscopy coupled with an X-ray microanalyzer. Lead accumulation was observed in the apoplasm and in the cytoplasm, vacuoles, and as distinct globules (potentially as lead-lignin or lead-phosphate complexes) on the cell membrane and cell wall. We conclude that the ability of scented geraniums to tolerate high lead accumulation in its biomass is due, in part, to limiting damage to photosynthetic apparatus and metal detoxification by formation of metal complexes.     

Lead accumulation and distribution in maize seedlings: Relevance to biomass production and metal phytoextraction

Among trace metals, lead is a highly toxic contaminant, being hazardous to humans and animals. Application of maize plants for phytoremediation of polluted soils and waters has recently been of particular interest. The aim of this work is to investigate the Pb-phytoextraction potential of the maize cv. Tzariza used widely in Eastern European agriculture. Maize seedlings were exposed in a nutrient solution to 1–10000 µM of Pb²⁺ for 21 days. Lead accumulated mostly in conductive tissues and shoots at 0.1 mM and higher concentrations of Pb in growth medium. Pb at concentrations of 1 and 10 mM caused an increase in the superoxide anion level and the catalase activity in maize leaves. Lead ions were tolerable to maize seedlings within a concentration range up to 1000 µM of Pb^2+. The levels of lead in the nutrient solution above 1 mM resulted in inhibition of the growth of axial organs, decrease in leaf area, inhibition of water absorption, and reduction in accumulation of biomass. Theoretical considerations indicate that in the temperate climates of the phytoremediation with maize may allow annual removal up to 90 kg of Pb per km², depending on the initial level of soil contamination.     

Cd、Pb对蟾蜍肝脏超氧化物歧化酶活性及其同工酶的影响

以腹腔注射法分别对蟾蜍(Bufobufogargarizans)给Cd和Pb (按镉计0 . 2、0 . 4、0 . 8、1 .6mg/kg体重;按铅计2、4、8、16mg/kg体重) ,连续染毒7d后,观察不同浓度Cd、Pb染毒条件下的蟾蜍肝超氧化物歧化酶(SOD)活性及其同工酶的变化。结果表明:在0 . 2mg/kg、0 4mg/kgCd和4mg/kg、8mg/kg和16mg/kgPb染毒,下蟾蜍肝SOD活性被显著诱导(P <0 . 0 5 ) ;前者酶带2 (Rf=0 . 4 3)活性增强,且均比对照增加1条新酶带(Rf=0 . 38) ;后者只表现为酶带1(Rf=0 . 5 1)和酶带2 (Rf=0 . 4 3)活性的增强,无新酶带的出现。     

The use of ally-trenbolone as a progestational agent to maintain pregnancy in ovariectomized bitches

The administration of the synthetic progestogen, allytrenbolone, at a dose of 0.088 mg/kg/d per os successfully maintained pregnancy in 3 of 3 bitches ovariectomized at 34 to 42 d of gestation and in 1 of 3 ovariectomized on Day 8 or 9 of gestation. However, a dose of 0.044 mg/kg/d per os maintained pregnancy in only 2 of 6 bitches ovariectomized in mid-gestation. Two bitches that had ovariectomies performed on Day 9 of gestation and were supplemented with ally-trenbolone at a dose of 0.088 mg/kg/d per os did not establish a pregnancy that was detectable by mid-gestation. Although inhibited the first 2 d post partum in some bitches, lactation increased sufficiently to successfully maintain pups.     

Carnosine and anserine in working muscles--study using proton NMR spectroscopy]

NMR spectroscopy was used to study carnosine and anserine metabolism in rat tissues under intensive muscle loading. Muscle loading was accompanied by the dipeptide (predominantly anserine) accumulation in muscle tissues. Preliminary per os administration of carnosine (250 mg/kg of body mass) did not increase the dipeptide content in muscle tissues but diminished the lactate content in rat muscles under intensive muscle loading.