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1.
Chronic fluoride toxicity in the form of dental fluorosis was observed in cattle from nine (9) villages under two (2) blocks of Nayagarh district of Orissa. Out of 1117 cattle, 221 (18.09%) showed the signs of dental fluorosis. In all affected villages, the prevalence of dental fluorosis in calves (< 1 year age) was greater than adults. There was significant difference in prevalence in respect to age. The commonly observed signs of dental fluorosis were brown discoloration, mottling, attrition or uneven wearing of teeth with or without pitting. None of the affected animals showed characteristic signs of osteofluorosis. The mean serum and urine fluoride concentration of affected animals were significantly (P < 0.05) higher than those of control animals. Fluoride levels (mean) of ground water and surface water in two blocks were 1.30 +/- 0.16 ppm, 0. 66 +/- 0.08 ppm and 1.12 +/- 0.19 ppm, 0. 48 +/- 0.05 ppm respectively. The fluoride content of grass samples of affected and control (non-endemic) area was comparable. There was a highly positive correlation (r = + 0.664) between prevalence of dental fluorosis and fluoride content of ground water. It was concluded that fluoride intake through the water especially ground water contributed to the development of fluorosis in cattle.  相似文献   

2.
Protective effects of quercetin against oxidative stress induced by sodium fluoride intoxication in rat erythrocytes were evaluated. Rats were divided into five groups consisting of 10 in each for this experiment. The animals of group I received water and standard diet to serve as control group, the animals of groups II and III were treated with quercetin (10 and 20?mg?kg?1 body weight), administrated intraperitoneally for 7 days followed by sodium fluoride (600?ppm) in drinking water for the next 7 days. The animals of group IV were treated with vitamin C (10?mg?kg?1) intraperitoneally for 7 days followed by sodium fluoride treatment for next 7 days serving as positive control group. The animals of group V were treated only with sodium fluoride (600?ppm) for the same time and were used as control group. Blood sample were collected via retro-orbital puncture. The antioxidant enzymes, superoxide dismutase, and catalase, as well as the levels of reduced glutathione and lipid peroxidation end products were measured in erythrocytes. There was a significant increase in lipid peroxidation along with a decrease in superoxide dismutase activity in the erythrocytes of sodium fluoride-treated animals. Quercetin treatment prior to fluoride administration normalized the levels of all parameters measured in the rat erythrocytes.  相似文献   

3.
Tertiary-butyl acetate (TBAC) (CAS No. 540-88-5) is an organic solvent with a potential for occupational and environmental exposure as a result of its use in industrial coatings, adhesives, inks, and degreasers. The objective of these studies was to extend the toxicological database upon which health hazard and risk assessments of TBAC can be made. The metabolism of TBAC was studied in rats exposed by inhalation for 6?h to concentrations of 100 or 1000?ppm. There was an evidence of partial saturation of TBAC absorption and metabolism at some concentration below 1000?ppm. Approximately 5% of the low dose and 26% of the high dose was expired without change within 12?h, while the retained material was rapidly metabolised and excreted, mostly in the urine, within 24?h. Very little radioactivity remained in the tissues after day 7. The metabolism of TBAC appears to follow two major routes: hydroxylation of the tertiary-butyl moiety to form 2-hydroxymethylisopropyl acetate and ester hydrolysis to form tertiary-butyl alcohol (TBA). A minor route involves oxidation of the acetate moiety. Based on the proportion of metabolites that can clearly be assigned to one or the other major pathway, hydroxylation of the tertiary-butyl moiety prevails at 100?ppm, while hydrolysis of the ester bond predominates at 1000?ppm.

Based on nose-only inhalation exposure of rats to TBAC for 6?h, the LC50 for males and females combined is approximately 4200?ppm. Clinical signs included exaggerated breathing, staggering, tremors, and lethargy approximately 1?h after the exposure, but all surviving rats appeared normal from 24?h until the end of the 14?day observation period. An LC50 was not identified for mice. After exposure of whole body for 6?h to 3000?ppm, the highest concentration tested, all mice were prostrate for most of the exposure time, but there were no deaths.

Groups of five male and five female Sprague-Dawley rats were exposed nose-only to 0, 100, 400, or 1600?ppm TBAC 6?h?day?1 5 days?wk?1 for 2?weeks. There were no effects on body weight, feed or water consumption, or necropsy findings. Male rats exposed to 1600?ppm had increased liver weights and hypertrophy of centrilobular hepatocytes. An increased proportion of cortical tubule cells with hyaline droplet accumulation was observed in all treated groups of males. Groups of five male and five female CD-1 mice were exposed whole body to 0, 190, 375, 750, or 1500?ppm TBAC 6?h?day?1 for 14 consecutive days. There were no effects on body weight, feed consumption, or necropsy findings. Liver weights were increased in female mice at 750 and 1500?ppm. Minimal hypertrophy of centrilobular hepatocytes was found in female mice at 375, 750, and 1500?ppm and in male mice at 1500?ppm TBAC.

TBAC did not induce gene mutations in bacterial tests with strains of S. typhimurium and E. coli. Further, there was no evidence of clastogenic activity from tests either for the induction of chromosomal aberrations in human lymphocytes in vitro in the presence or absence of S9 mix or for the induction of micronuclei in bone marrow cells of rats exposed by inhalation for 6?h to 1600?ppm TBAC.

These results are relevant to human health risk assessment and are discussed in the context of previous studies. The weight of the scientific evidence supports the conclusion that TBAC has lower acute toxicity than previously suggested, that it is rapidly excreted when inhaled, and that neither TBAC nor its TBA metabolite are genotoxic or potential human carcinogens.  相似文献   

4.
为了解Cd Te/Zn SQDs(Cd Te/Zn S量子点)在小鼠肾脏中的药代动力学特征,选择雄性ICR(Institute of Cancer Research)小鼠为动物模型,每只单次尾静脉注射5 nmol的Cd Te/Zn SQDs(粒径约为6 nm,最大发射波长590 nm)。在尾静脉注射Cd Te/Zn SQDs 15 min、1 h、6 h、24 h、72 h、168 h、2 w、4 w和6 w时剖取小鼠的肾脏,消化后使用电感耦合等离子体质谱(ICP-MS)检测其中的Cd(镉)和Te(碲)含量,Cd和Te在小鼠肾脏中浓度随时间的变化均呈现先增加后降低的趋势,Cd和Te含量分别在168 h和72 h时达到峰值(60.42±8.85)ng·g~(-1)和(18.69±0.97)ng·g~(-1),之后逐渐下降,将二者的含量以摩尔比表示,随着给药时间的延长,摩尔(Cd):摩尔(Te)由2.71:1逐渐变成1.39:1。利用3P87计算Cd和Te在肾脏中的药代动力学参数,结果发现Cd和Te在肾脏中的Vd(表观分布体积)分别为(823.14±82.76)g·kg~(-1)和(686.28±53.13)g·kg~(-1)(P0.05);AUC(药物浓度-时间曲线下面积)分别为(24.48±2.52)μg·g~(-1)·h和(7.41±0.60)μg·g~(-1)·h(P0.01);CL(清除率)分别为(0.90±0.11)g·kg~(-1)·h~(-1)和(1.02±0.13)g·kg~(-1)·h~(-1)(P0.05);t1/2(半衰期)分别为(617.02±8.57)h和(458.21±1.85)h(P0.01)。研究提示Cd和Te在肾脏含量的摩尔比随时间变化不同,QDs在体内发生了化学降解;二者的药代动力学参数不同,Cd在肾脏中的代谢速度明显慢于Te,游离的Cd2+可能引起肾脏毒性。  相似文献   

5.
Abstract

Andrographolide sodium bisulfite (ASB) widely used for intestinal infections and respiratory tract infections. It has been reported to frequently cause acute renal failure in clinical practice. The purpose of this study was to evaluate the nephrotoxicity and toxicokinetics in Sprague-Dawley rats after a single-dose injection of ASB administered at 100, 600, and 1000?mg/kg via intravenous tail injections. The concentrations in plasma and kidney microdialysates were analyzed by high-performance liquid chromatography. Blood urea nitrogen and creatinine levels in plasma were determined and toxicokinetic parameters were observed. In plasma and kidney, the elimination constant and clearance were decreased and the half-time was increased with increasing dose. Blood urea nitrogen and creatinine were positively correlated with ASB concentration indicating the potential for accumulation in kidney that can eventually lead to damage.  相似文献   

6.
Occurrence and problems of high fluoride waters in Turkey: an overview   总被引:1,自引:0,他引:1  
Endemic dental fluorosis was first observed in Turkey in Isparta Province, located in the SW of Anatolia, with mottled enamel related to the high levels of fluoride (1.5–4.0 ppm) in drinking waters, about 55 years ago. The origin of fluoride was attributed to the contents of minerals in volcanic rocks, consisting of pyroxene, hornblende, biotite, fluorapatite and glassy groundmass minerals. It was also reported about 35 years ago that severe dental and skeletal fluorosis has been observed in human beings and livestock in Dogubeyaz?t and Caldiran areas, located around Tendurek Volcano in eastern Turkey, where natural waters contained fluoride levels between 2.5 and 12.5 ppm. It was hypothesised that fluoride, which might be transported by fumaroles or escaped from devitrified lavas, could be held on the surface of some minerals and then exchanged with OH- in ground waters with high pH at the foothills of the young Tendurek Volcano. Endemic dental and skeletal fluorosis was also observed in the inhabitants in Kizilcaoren Village of Beylikova Town in Eski?ehir Province situated in the midwest of Turkey, where the fluoride content of the drinking waters ranged from 3.9 to 4.8 ppm. The origin of high fluoride in the natural waters was related to the fluorspar deposits, occurring in the catchment area near the village. During the survey in the Güllü Village of Esme-Usak, located in south-midwest of Turkey, it was observed that most of the inhabitants born and raised in the village and aged between 10 and 30 years, showed mild to moderate levels of mottled enamel. The fluoride contents of the deep well waters used for drinking in the village, varied from 0.7 to 2.0 ppm. Amorphous microscopic fluorite existing in the Pliocene lake limestones was considered as a possible origin of fluoride in the waters.  相似文献   

7.
Fish exposed to 150 ppm and 250 ppm doses saparately, showed eratic swimming with hyper-excitability, spiralling, convulsion and mortality. However at 350 ppm dose fish became lethargic and steady at the bottom of aquarium. This behaviour appears to be due to sedative effects of fish implicating the phychoactive nature of the plant B. Ianzan. At 150 ppm to 350 ppm doses, fish scale changed from reticulate to punctate chromatophores; and treated fish when transferred to fresh water, were slowly regained to normal behaviour after 96 h exposure. Hence doses regaining from 150 ppm to 350 ppm is considered to be psychoative in nature. In higher doses 450 ppm and 550 ppm fish could survive only 76 h and 4.30 h respectively and then died indicating toxicity of plant for the said doses. It is found that scale present on its body is most suitable test system for the study of psychoactivity and toxicity of plant extracts on fish, Labeo rohita.  相似文献   

8.
To determine the effects of noise exposure on hearts of newborn mice, 48 pregnant mice were exposed to recorded aircraft flight noise (100?dB) for 150?min from the 2nd day of pregnancy to 7th day after delivery. Mice of the same age were selected as control group. The weights and crown-rump lengths of the fetuses and the newborns were measured, and their hearts were removed under deep anesthesia on the 1st, 7th, and 14th days after birth and prepared histologically. Quantitative changes of the hearts were measured stereologically by the Cavalieri method. The ultrastructural changes of cardiac myocytes were examined using transmission electron microscopy. No histological changes were observed, but the volumes of newborns’ hearts in the experimental groups increased significantly compared to the control group. Photomicrographs of cardiac muscle cells revealed nuclear envelope changes, chromatin condensation, and increased mitochondria and myofibrils in noise-exposed newborns. It is concluded that the newborns of pregnant mice exposed to noise stress have hypertrophic hearts with ultrastructural changes.  相似文献   

9.
Barbaro  A.  Francescon  A.  Polo  B.  Bilio  M. 《Marine Biology》1978,46(3):247-257
The capacity of the barnacle Balanus amphitrite Darwin to accumulate pollutants above ambient levels was examined in two North Adriatic lagoons with respect to fluoride, copper, lead, chromium and mercury. Levels in soft tissues ranged from 138 to 312 ppm (dry weight) for fluoride, 41 to 109 ppm for copper, 7.1 to 11.7 ppm for lead, 2.10 to 3.89 ppm for chromium, and from 0.96 to 1.35 ppm for mercury. The concentration factor was of the order of 102 for fluoride, 103 for copper, and possibly higher than 103 for lead, chromium and mercury. The differences of about 2:1 in the fluoride and copper concentrations in the waters of the two lagoons were clearly reflected by the levels in the barnacles. B. amphitrite that had set on experimental panels had levels similar to those found in specimens collected from long-term natural populations as early as 42 days after immersion of the panels. Compared with literature data, the accumulation levels found in B. amphitrite for fluoride were among the highest known for invertebrates; the values for copper and lead were considerable, but exceeded by others published for B. balanoides; the results for chromium and mercury were one order of magnitude lower than values reported for other suspension-feeders or indicator organisms. B. amphitrite appears to possess most of the properties considered essential for a biological indicator. Eventual determination of the response time of the barnacle to changes in environmental level could profitably be carried out utilizing experimental panels.  相似文献   

10.
The indiscriminate and injudicious use of pesticides particularly endosulfan in agriculture and animal husbandry practices has considerably increased the risk of human health hazard. The present work was therefore undertaken to evaluate the toxic effect of endosulfan on the vital organs viz. liver and kidney of rat. Oral administration of endosulfan at the dose level of 10 mg/kg b.wt./day for two and four weeks showed toxic interference with the biochemistry and histology of rat liver and kidney. The biochemical parameters viz. Aspartate amino transferase, alanine amino transferase, acid phosphatase, alkaline phosphatase, bilirubin urea and creatinine were increased which clearly showed the hepato and nephrotoxic effect of endosulfan. Histopathologically the size of liver was increased, sinusoidal dilation, pyknotic nuclei, cytoplasmic degranulation and various nuclear aberrations were observed. Similarly pathological alterations viz. chronic glomerulonephritis, glomerulosclerosis, odenoma and glomerulus deposits were observed in the kidney.  相似文献   

11.
Five week-old mice were divided into a vehicle control group, and groups exposed to ZnO nanoparticles at low (0.5 g/kg), middle (1 g/kg), high (3 g/kg), and exceptionally high-dose (5 g/kg). After the first, second, third, and fourth weeks’ of exposure, blood biochemistry, histopathology, and electron microscopic ultrastructural changes in liver, kidney and spleen were investigated. Increased alkaline phosphatase activities were observed in all treated mice being statistically significant at higher dose. No changes were observed in the serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, creatinine, blood urea nitrogen, and lipid levels. During the first and second weeks of the treatment, effects on the cytoarchitecture of liver, kidney, and spleen were not perceived while during the third and fouth weeks of treatment sporadic mild effects were seen. Ultrastructural electron microscopic changes in liver, kidney, and spleen were not observed for the low-dose group on the first, second, third, and fourth weeks, suggesting that exposure to ZnO nanoparticles at low dose is safe. Long-term (i.e., more than 28 days) exposure to the exceptionally high-dose resulted in sporadic changes in nuclear chromatin condensation, irregular nuclear membrane, polymorphic mitochondria, mitochondrial swelling, and vacuolation. ZnO nanoparticles could be well tolerated and no death occurred in any group of treated mice.  相似文献   

12.
Accumulation rates of cadmium, the amount of food ingested and assimilated, the amount of oxygen consumed and changes in dry flesh weight have been measured in Mytilus edulis L. exposed to 0, 10 and 100 ppb cadmium for 17 d in aquaria with seawater flowing continously and at constant algal concentration. The accumulation rates were linear at 10 and 100 ppb, amounting to 0.58 and 8.89 ppm d-1, respectively. Body loads up to 150 ppm caused no effects on either clearance, ingestion, assimilation, respiration, or growth. High net growth efficiencies between 55–59% were obtained, indicating near optimal experimental conditions. It is suggested that the setup and experimental procedure provide an excellent tool in the study of accumulation and sublethal effects of environmental pollutants in suspension feeding bivalves.  相似文献   

13.
To enhance the phytoremediation ability of the heavy metal accumulator Perilla frutescens, melatonin (MT) was applied at different concentrations (0, 25, 50, 100, 150, and 200?μmol/L) to P. frutescens growing in cadmium (Cd) contaminated soil (10?mg/kg). The MT treatments increased the root and shoot biomasses of P. frutescens, with the maximum increase in the 150?μmol/L MT treatment (79.51% and 36.18% higher, respectively, than those of the control). The MT treatments also enhanced superoxide dismutase activity, peroxidase activity, and the soluble protein concentration of P. frutescens, and 100–200?μmol/L MT increased the chlorophyll a, chlorophyll b, and total chlorophyll concentrations in P. frutescens. The MT treatments increased the Cd concentrations in roots and shoots of P. frutescens in a dose-dependent manner. Different MT concentrations increased the Cd accumulation amounts of roots and shoots of P. frutescens, with the maxima accumulation amounts in the 150?μmol/L MT treatment (226.98% and 85.89% higher, respectively, than those of the control). These results show that MT can promote the growth and phytoremediation ability of P. frutescens growing in Cd-contaminated soil, and the optimum MT dose is 150?μmol/L.  相似文献   

14.
Fluorosis is a serious public health problem in many parts of the world. The generation of reactive oxygen species and lipid peroxidation has been considered to play an important role in the pathogenesis of chronic fluoride toxicity. The present study was undertaken to evaluate the protective effect of Tamarindus indica fruit pulp extract on the collagen content and oxidative stress in liver and kidney of fluoride-exposed rats. The first group served as control. The second group received 200 mg L?1 of sodium fluoride through drinking water. The third and fourth groups received T. indica fruit pulp extract (200 mg kg?1 body weight) alone and along with fluorinated drinking water respectively, daily by gavage for a period of 90 days. At the end of the experiment, blood samples were collected from all groups, and liver and kidney samples were taken concurrently. Levels of malondialdehyde and glutathione and the activities of superoxide dismutase and catalase were evaluated in the liver and kidney of experimental rats. Furthermore, level of hydroxyproline and histological examination of liver and kidney along with serum biochemical parameters were evaluated. In conclusion, fluoride was determined to cause adverse effects in rats, and the supplementation of tamarind to these animals alleviated the adverse effects of fluoride.  相似文献   

15.
Oocyte maturation, embryo development and expression of apoptotic-specific genes were evaluated in blastocysts of mice treated with titanium dioxide nanoparticles. Female mice received 0, 50 or 100?mg/kg/day titanium dioxide intraperitoneally for five consecutive days. After the last injection, pregnant mare serum gonadotropin and, 48?h later, human chorionic gonadotropin were administered intraperitoneally for induction of ovulation. After 14?h, mice were sacrificed and oocytes were collected. The number of mature oocytes was evaluated and then fertilization was carried out in vitro and the numbers of fertilized and cleaved oocytes and of blastocysts and the expression of Bax, caspase 3, and Bcl-xL genes in blastocysts were evaluated. The number of mature, fertilized and cleaved oocytes and of blastocyst embryos in the experimental groups were not different from control. The expression of Bax and caspase 3 genes was significantly elevated in the experimental groups compared to control, while expression of the Bcl-xL gene was significantly lower in the high dose group. Uptake of titanium dioxide nanoparticles at daily doses of 50?mg/kg and more may affect embryo development by alteration of pro-apoptotic and anti-apoptotic gene expression.  相似文献   

16.
Persistent organic pollutants such as Polychlorinated biphenyls (PCB) and dichloro diphenyl trichloroethane (DDT) are known to exert various adverse health effects in wildlife mammals. The impact from dietary intake of minke whale (Balaenoptera acutorostrata) blubber high in organohalogen and other chemical contaminants on renal morphology and function was investigated via a controlled study on West Greenland sledge dogs (Canis familiaris). Our results showed significantly higher frequencies of glomerular, tubular, and interstitial lesions in the exposed group. Furthermore, higher urine protein?:?creatinine ratio and plasma urea levels were found in the exposed group, which indicated a negative impact on kidney function via tubular and glomerular dysfunctions. The lesions were similar to those observed in top predator marine species–such as seals and polar bears–and humans exposed via diet to persistent environmental pollutants. The lesions may have impacts on the overall health of these animals. It is reasonable to suggest that chronic exposure to organic pollutants via a country diet of high trophic level marine organisms may have an impact on renal morphology and function in Arctic apex predators in general as well as Inuit people.  相似文献   

17.
The aim of this study was to investigate the nephroprotective and antioxidant property of Manasamitra vatakam (MMV) against aluminum (Al)-induced toxicity in rats. The kidney function marker parameters such as serum urea, uric acid, and creatinine were significantly increased in Al-treated rats as compared with controls. Similarly, the antioxidant enzyme activities such as superoxide dismutase, glutathione S-transferase, Na+/K+-ATPase and Mg-ATPase, reduced glutathione were also found significantly increased in Al-treated rats. A significantly decreased level of these parameters was observed in the MMV (orally 100?mg?kg?1 body weight)-treated group along with a reduced level of malonaldehyde, molecular chaperones of an antioxidative stress protein, and mRNA expression of HSP70. The biochemical observations were also supported by histopathological observations. Thus, this study supports the nephroprotective and antioxidant activities of MMV.  相似文献   

18.
为探讨纳米TiO2对肝、肾细胞DNA的损伤效应,实验制备了锐钛矿型纳米TiO2颗粒(20~100nm),并采用不同浓度的纳米TiO(20、0.1、0.2、0.4、0.8mg·mL-1)对25只昆明雄性小鼠进行染毒,5d后用单细胞凝胶电泳技术检测小鼠肝、肾细胞DNA的损伤程度.结果表明,随着纳米TiO2染毒浓度的升高,小鼠肝、肾细胞尾部DNA百分率(Tail DNA%)和尾矩(Tail Moment)均呈逐渐升高趋势;对于肝细胞,0.1mg·mL-1组Tail DNA%及Tail Moment与对照组无显著差异(p>0.05),≥0.2mg·mL-1组则显著升高(p<0.05或p<0.01);与肝细胞相比,肾细胞Tai lDNA%及Tail Moment变化更为显著,0.1mg·mL-1组即与对照组存在极显著差异(p<0.01).以上结果表明,纳米TiO2染毒可导致小鼠肝、肾细胞DNA损伤,且随染毒浓度的增加,损伤逐渐加重,呈一定的剂量-效应关系;与肝细胞相比,肾细胞对纳米TiO2更为敏感,较低浓度染毒即可造成DNA损伤.  相似文献   

19.
Liver alterations were stereologically determined in five groups, each of 10 male and female Sprague–Dawley weanling rats fed PCB 105 (2,3,3′,4,4′-pentachlorobiphenyl) for 13 weeks at concentrations of 0.05, 0.5, 5, and 50?ppm mixed with corn oil. Animals from two groups receiving the oil in diets served as controls for each gender. A significant increase in mean volume fraction (VF) of smooth endoplasmic reticulum (SER) profiles was estimated in hepatocytes of female rats in 0.5, 5, and 50?ppm groups. A significant decrease in VF of mitochondria in female rats at 50?ppm was detected. In addition, a decrease in VF of lipid droplets was measured in female rats at 0.5, 5, and 50?ppm groups. No difference was found in VF of rough endoplasmic reticulum (RER) cisternae, and peroxisome profiles at any concentration of the PCB in either male or female animals as compared to baseline values from controls. A significant elevation of baseline VF for RER in female rats was detected in comparison with males. In the present study, no observable adverse effect level (NOAEL) for PCB 105 was estimated at <0.5?ppm for hepatocyte alterations in female Sprague–Dawley rats.  相似文献   

20.
选取中华圆田螺为受试动物,探究氟对其肝胰脏抗氧化酶SOD、GSH、POD活性和丙二醛(MDA)含量的影响。结果显示,在不同浓度水氟环境条件下(0、40、80、160 mg·L~(-1))连续暴露10 d、20 d和30 d时,与对照组相比,中华圆田螺肝胰脏SOD活性在暴露前20 d,中低浓度组活性被诱导升高,高浓度组受抑制降低。暴露30 d时,中低浓度组活性降低,高浓度组逐渐升高。MDA含量在暴露前20 d时,中低浓度组活性整体被诱导升高,高浓度组受抑制降低。暴露30 d时,MDA含量受到显著抑制均低于对照组。GSH活性以诱导为主均高于对照组,POD活性在10 d时均低于对照组,而在20 d时被诱导升高且均高于对照组,30 d时中高浓度以抑制为主。上述研究结果为水质污染控制及生态风险评价提供了基础数据。  相似文献   

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