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521.
The ever-increasing use of pesticides in the agricultural and public health has become a major cause of sterility in human and various other animals particularly in males. This study was sought to screen the toxic impacts of cypermethrin (synthetic pyrethroid) on reproduction and development. Twenty-four Wistar male rats divided into four groups were orally administered cypermethrin of daily doses 50, 75, or 100 mg?kg?1 bwt per day for 45 days; and for developmental toxicity, 12 female rats were separated into two groups. Maternal rats (experimental) were administered cypermethrin (100?mg?kg?1) by gavage daily from 6th to 17th day of gestation, and the control group was dosed only vehicle (olive oil). The body weights, fertility index, biochemical, enzymatic, hormonal, and histopathological parameters were the criteria used to evaluate the toxicity of cypermethrin. Study showed significant decline in the weight of testes, epididymises, seminal vesicles, and ventral prostate, and reduction in sperm counts both in epididymises and testes in chemical-treated animals. Pre- and post- fertility test showed 50%, 80%, and 100% negative results after treatment. A significant degenerative reduction in testicular glycogen and sialic acid was also noted. In contrast, protein and cholesterol levels of testes were significantly increased. In addition, acid phosphatase activity was significantly increased, while alkaline phosphatase, testosterone, leutinizing hormone (LH), and follicle stimulating hormone (FSH) levels were diminished. Histology of testes showed degenerative changes in seminiferous tubules. Cypermethrin exposure during gestation produced adverse effects markedly in females and fetuses. 相似文献
522.
Chantel D. Sloan Joann F. Gruber Kevin M. Mwenda Jason H. Moore Tracy Onega 《毒物与环境化学》2013,95(3):605-615
Indoor and outdoor air pollution is known to contribute to increased lung cancer incidence. This study is the first to address the contribution of home heating fuel and geographical course particulate matter (PM10) concentrations to lung cancer rates in New Hampshire, USA. First, Pearson correlation analysis and geographically weighted regression were used to investigate spatial relationships between outdoor PM10 and lung cancer rates. While the aforementioned analyses did not indicate a significant contribution of PM10 to lung cancer in the state, there was a trend towards a significant association in the northern and southwestern regions of the state. Second, case-control data were used to estimate the contributions of indoor pollution and secondhand smoke to the risk of lung cancer with adjustment for confounders. Increased risk was found among those who used wood or coal to heat their homes for more than 10 winters before the age of 18, with a significant increase in risk per winter. Resulting data suggest that further investigation of the relationship between heating-related air pollution levels and lung cancer risk is needed. 相似文献
523.
Neelam Dwivedi Sandeep Kumar Ashish S. Verma Ghanshyam D. Gupta K.K. Dutta 《毒物与环境化学》2013,95(9):1572-1580
Furfural is an industrial compound used as a process intermediate and as a solvent; it poses a potential inhalation hazard in occupational settings. This study was carried out to find furfural-induced immunotoxicity in Wistar rat following inhalative exposure. The weights of thymus and lymph node were found decreased, while the weights of the liver and the adrenal gland were significantly increased following furfural exposure. Delayed-type hypersensitivity response was found decreased in furfural vapors-exposed animals when compared to that of control animals. The phagocytic index of peritoneal and alveolar exudates showed significant decrease and was most prominent (90%) in 30 days-exposed groups. The number of anti-rat anti-sheep red blood cell immunoglobulin M plaque forming cells of spleen got decreased in furfural-exposed groups in comparison to control. Taken together, this study indicates that inhalation of furfural induces immunotoxic manifestations that could lead to severe immunological disorders. 相似文献
524.
The aim of the present study was to evaluate the potential toxicity and general mechanisms involved in single walled carbon nanotubes (SWCNTs)-induced cytotoxicity using human embryonic kidney cell line (HEK293) cells. Carbon nanotubes (coded as CNT) used in this study were synthesized by the chemical vapor deposition method. To elucidate the possible mechanisms underlying SWCNT-induced cytotoxicity, cell viability, cell membrane damage (lactate dehydrogenase activity (LDH) assay), reduced glutathione (GSH), interleukin-8 (IL-8) and lipid peroxidation products levels were quantitatively assessed following SWCNT exposure for 48 hr using HEK293 cells. Exposure of cells to SWCNT at 3–300 μg/ml produced significant reduction in cell viability in a concentration-dependent manner. The IC50 value of SWCNT was found to be 87.58 μg/ml. Exposure of HEK cells to SWCNT at 10–100 μg/ml resulted in concentration-dependent cell membrane damage, increased production of IL-8, elevated levels of thiobarbituric acid reactive substances like malondialdehyde and decreased intracellular GSH levels. In summary, exposure to SWCNT resulted in a concentration-dependent cytotoxicity in cultured HEK293 cells that was associated with increased oxidative stress. 相似文献
525.
Eutrophication control programs are based on phosphorus management which, in turn, requires a detailed quantification of the watershed phosphorus budget. This involves an assessment of non‐point sources of phosphorus, a key element of which is determining the fraction of soil‐P and sediment‐P available to support algal growth. This paper presents a review of the state‐of‐the‐art of estimating algal available‐P from non‐point sources, and an analysis of pertinent data. The need to employ multi‐interval algal bioassays in developing phosphorus management systems is stressed. 相似文献
526.
Differential Pulse Anodic Stripping Voltammetry (DPASV) was employed to measure Apparent Copper Complexing Capacity (Lt) and Stability Constants (Ks) of related cupric complexes of cell exudates of the phytoplanktonic alga Dunaliella salina. Three natural seawater samples collected 0.1, 2, 5 miles off the Tyrrhenian coast were used as culture medium. The measurements were carried out 1h and 7 days after the inoculum. Furthermore, on one culture the medium was passed through C18‐SEP‐PAK cartridges in order to separate the cell exudates. The results show that Dunaliella salina influences the value of Lt but does not affect the value of Ks . The C18SEP‐PAK retain only 50% of the ligands produced by the cells and capable of complexing copper. 相似文献
527.
During the years 1983–1986, a program aiming at monitoring water quality of the most crowded beaches, as well as assessing and minimizing pollution from certain land based sources was carried out in Rhodes and Cos. The program was directed towards inspections of treatment plants as well as laboratory analyses of treated effluents from large hotels. As a result, almost one in four hotels was obliged to construct a new treatment plant. In order to help personnel to improve plant efficiency through day‐to‐day maintenance a three day seminar was held in June 1985. Sea water quality parameters (total coliforms and E. coli) were found to be well below the limits set by E.E.C. directives. 相似文献
528.
Male albino rats were fed for 28 days from weaning on diets containing 5% (group 1), 10% (group 2) and 21% (group 3, normal protein) protein as casein. At the end of dietary period, HCH was administered daily for 30 days to investigate the interaction between protein deficiency and pesticide toxicity. The results indicated that rats fed a lower protein diet and HCH had a higher mortality, lower rate of growth, increased liver weight and deposition of the pesticide in blood and tissues in larger amounts. Blood pressure (systolic and diastolic) was significantly increased and the heart rate showed tachycardia in low protein exposed animals. A significant increase of total lipids, cholesterol, triglycirides, free fatty acids in serum and tissues of animals exposed to low protein was observed. A close correlation existed between lipid accumulation and storage of HCH in tissues and dietary protein seemed to play an important role in detoxification. 相似文献
529.
TSP samples, collected at two stations in the area of Thessaloniki during the period July 1987‐June 1988, were analysed for heavy metals (Fe, Pb, Zn, Cu, Mn, Cr, Co, Ni and V). Flame and flameless atomic absorption spectrophotometry was used for metal determinations. Metals determined were characterized with respect to their origin from natural or man‐made emission sources. Source identification was attempted by relation of metal concentrations to wind direction, and interelement correlations. Results obtained showed that Pb, Zn and Cu are emitted from man‐made sources (traffic, domestic heating, industry), V, Ni and Co are derived partially from natural and man‐made sources, while Cr is mainly soil‐derived. 相似文献
530.
The persistence of atrazine, linuron and fenitrothion in soil samples from an estuarine area (Ebro delta, Tarragona, Spain) has been studied. Soil samples from the top surface (10 cm) were collected during 1989–91, freeze‐dried, sieved through 200 μm, Soxhlet extracted with methanol, cleaned‐up with Florisil and analysed either by gas chromatography‐nitrogen phosphorus detection (GC‐NPD), in the case of atrazine and fenitrothion, or by liquid chromatography with diode array detection (LC‐DAD), for linuron. Confirmation of the samples analysed by GC‐NPD was carried out using GC‐mass spectrometric detection (MS) in the electron impact mode. The soil half lives obtained under the real environmental conditions have been calculated and the values obtained have been correlated with the physicochemical properties of each pesticide and the soil type. Degradation was affected by volatilization since temperatures in the area of study are relatively high, ca. 30°C, in the summer period. In the case of atrazine it has been shown that deethylatrazine is formed in all the samples studied.. 相似文献