Уточнить поиск
Результаты 3471-3480 из 4,033
Source-specific sewage pollution detection in urban river waters using pharmaceuticals and personal care products as molecular indicators
2016
Kiguchi, Osamu | Sato, Go | Kobayashi, Takashi
Source-specific elucidation of domestic sewage pollution caused by various effluent sources in an urban river water, as conducted for this study, demands knowledge of the relation between concentrations of pharmaceuticals and personal care products (PPCPs) as molecular indicators (caffeine, carbamazepine, triclosan) and water quality concentrations of total nitrogen (T-N) and total phosphorous (T-P). River water and wastewater samples from the Asahikawa River Basin in northern Japan were analyzed using derivatization-gas chromatography/mass spectrometry. Caffeine, used as an indicator of domestic sewage in the Asahikawa River Basin, was more ubiquitous than either carbamazepine or triclosan (92–100 %). Its concentration was higher than any target compound used to assess the basin: <4.4–370 ng/L for caffeine, <0.6–3.9 ng/L for carbamazepine, and <1.1–13 ng/L for triclosan. Higher caffeine concentrations detected in wastewater effluents and the strongly positive mutual linear correlation between caffeine and T-N or T-P (R ² > 0.759) reflect the contribution of septic tank system effluents to the lower Asahikawa River Basin. Results of relative molecular indicators in combination with different molecular indicators (caffeine/carbamazepine and triclosan/carbamazepine) and cluster analysis better reflect the contribution of sewage than results obtained using concentrations of respective molecular indicators and cluster analysis. Relative molecular indicators used with water quality parameters (e.g., caffeine/T-N ratio) in this study provide results more clearly, relatively, and quantitatively than results obtained using molecular indicators alone. Moreover, the caffeine/T-N ratio reflects variations of caffeine flux from effluent sources. These results suggest strongly relative molecular indicators are also useful indicators, reflecting differences in spatial contributions of domestic sources for PPCPs in urban areas.
Показать больше [+] Меньше [-]Pharmaceutical wastewater being composite mixture of environmental pollutants may be associated with mutagenicity and genotoxicity
2016
Sharīf, ʻAlī | Ashraf, Muhammad | Anjum, Aftab Ahmed | Javeed, Aqeel | Altaf, Imran | Akhtar, Muhammad Furqan | Abbas, Mateen | Akhtar, Bushra | Saleem, Ammara
Pharmaceutical industries are amongst the foremost contributor to industrial waste. Ecological well-being is endangered owing to its facile discharge. In the present study, heavy metals and organic contaminants in waste water were characterized using atomic absorption spectrophotometer and GC-MS, respectively. Mutagenicity and genotoxic potential of pharmaceutical waste water were investigated through bacterial reverse mutation assay and in vitro comet assay, respectively. Ames test and comet assay of first sample were carried out at concentrations of 100, 50, 25, 12.5, 6.25 % v/v effluent with distilled water. Chromium (Cr), lead (Pb), arsenic (As), and cadmium (Cd) were found in high concentrations as compared to WHO- and EPA-recommended maximum limits. Arsenic was found to be the most abundant metal and its maximum concentration was 0.8 mg.L⁻¹. GC-MS revealed the presence of lignocaine, digitoxin, trimethoprim, caffeine, and vitamin E in waste water. Dose-dependent decrease in mutagenic index was observed in both strains. Substantial increase in mutagenicity was observed for TA-100, when assay was done by incorporating an enzyme activation system, whereas a slight increase was detected for TA-102. In vitro comet assay of waste water exhibited decrease in damage index and percentage fragmentation with the increase in dilution of waste water. Tail length also decreased with an increase in the dilution factor of waste water. These findings suggest that pharmaceutical waste water being a mix of different heavy metals and organic contaminants may have a potent mutagenic and genotoxic effect on exposed living organisms.
Показать больше [+] Меньше [-]Cumulative effect of zinc oxide and titanium oxide nanoparticles on growth and chlorophyll a content of Picochlorum sp
2016
Hazeem, Layla J. | Bououdina, Mohammed | Rashdan, Suad | Brunet, Loïc | Slomianny, Christian | Boukherroub, Rabah
The use of nanoparticles (NPs) is of increasing significance due to their large potential for various applications. Great attention should be paid on the possible impacts of nanoparticles on the environment as large amounts of them may reach the environment by accident or voluntarily. Marine algae are potential organisms for usage in nanopollution bioremediation in aquatic system, because of their ability to adapt to long exposure to NPs. Thus, it is of prime importance to study the possible interactions of different NPs with microalgae in assessing their potential environmental risks. Most studies on potential environmental effects of ZnO and TiO₂ NPs have been performed independently and following the widely accepted, standardized test systems, which had been developed for the characterization of chemicals. In this study, we have examined the cumulative effect of ZnO and TiO₂ NPs on Picochlorum sp. in addition to the individual effects of these NPs over 32 days. Our results indicate that the toxicity and availability of NPs to marine algae are reduced by their aggregation and sedimentation. NPs are found to have a negative effect on algal growth and chlorophyll a concentration during the early growth stages. In contrast, the case is reversed during the late growth stages. There is no significant difference between the effect of the NPs when they are used separately and when both ZnO and TiO₂ are used together in the test (P > 0.05).
Показать больше [+] Меньше [-]Evaluation of geno-toxicity of methyl parathion and chlorpyrifos to human liver carcinoma cell line (HepG2)
2016
Patnaik, Rajashree | Padhy, Rabindra Nath
Insecticides and their residues are known to cause several types of ailments in human body. An attempt had been made to assess digitally the geno-toxicity of methyl parathion (MP) and chlorpyrifos (CP) to in vitro-grown HepG2 cell line, with Hoechst 33342 staining, comet, and micronucleus assays. Additionally, “acridine orange/ethidium bromide” (AO/EB) staining was done for the determination of insecticide-induced cytotoxicity, in corollary. Hoechst 33342 staining of cells revealed a decrease in live cell counts at 8–40 mg/L MP and 15–70 mg/L CP. Moreover, nuclear fragmentations in ranges 8 to 40 mg/L MP and 15 to 70 mg/L CP were recorded dependant on individual doses, increasingly with concomitant increases in comet tail length values. DNA fragmentation index measured in comet assays was 94.3 ± 0.57 at 40 mg/L MP and 93.3 ± 2.08 at 70 mg/L CP. Average micronuclei number was 59.0 ± 2.00 at 40 mg/L MP and 62.6 ± 1.52 at 70 mg/L CP, per 1000 cell nuclei, in micronucleus assay. Minimum inhibitory concentration (MIC) values with AO/EB staining for monitoring cytotoxicity were 4 and 10 mg/L for MP and CP, respectively. Lethal concentration₅₀ (LC₅₀) values were 20.89 mg/L MP and 79.43 mg/L CP in AO/EB staining, for cytotoxicity with probit analyses. It was concluded that MP was comparatively more geno-toxic than CP to HepG2 cell. It was discernible that at lower levels of each insecticide, geno-toxicity was recorded in comparison to cytotoxicity.
Показать больше [+] Меньше [-]NMR- and LC–MS/MS-based urine metabolomic investigation of the subacute effects of hexabromocyclododecane in mice
2016
Wang, Dezhen | Zhang, Ping | Wang, Xinru | Wang, Yao | Zhou, Zhiqiang | Zhu, Wentao
In the present study, both untargeted and targeted metabolomics approaches were used to evaluate the subacute effects of hexabromocyclododecane (HBCD) on mice urine metabolome. Untargeted metabolomics based on ¹H NMR showed that HBCD exposure disturbed mice metabolism in both dosed groups, especially in high dosed group. The low-dose HBCD led to a decrease in alanine, malonic acid, and trimethylamine (TMA). High-dose HBCD-treated mice developed high levels of citric acid and 2-ketoglutarate, together with decreased alanine, acetate, formate, TMA, 3-hydroxybutyrate, and malonic acid. Targeted metabolomics for metabolic profiling of 20 amino acids identified alanine, lysine, and phenylalanine as significantly disturbed metabolites. These results indicated that subchronic exposure to HBCD caused a disturbance of mice metabolism, especially in TCA cycle, lipid metabolism, gut microbial metabolism, and homeostasis of amino acids, and the application of untargeted and targeted metabolomics combined with conventional toxicology approaches to evaluate the subacute effects of pollutants will provide more comprehensive information and aid in predicting health risk of these pollutants.
Показать больше [+] Меньше [-]Technical feasibility study of a low-cost hybrid PAC-UF system for wastewater reclamation and reuse: a focus on feedwater production for low-pressure boilers
2016
Amosa, Mutiu Kolade | Jami, Mohammed Saedi | Alkhatib, Ma’an Fahmi R. | Majozi, Thokozani
This study has applied the concept of the hybrid PAC-UF process in the treatment of the final effluent of the palm oil industry for reuse as feedwater for low-pressure boilers. In a bench-scale set-up, a low-cost empty fruit bunch-based powdered activated carbon (PAC) was employed for upstream adsorption of biotreated palm oil mill effluent (BPOME) with the process conditions: 60 g/L dose of PAC, 68 min of mixing time and 200 rpm of mixing speed, to reduce the feedwater strength, alleviate probable fouling of the membranes and thus improve the process flux (productivity). Three polyethersulfone ultrafiltration membranes of molecular weight cut-off (MWCO) of 1, 5 and 10 kDa were investigated in a cross-flow filtration mode, and under constant transmembrane pressures of 40, 80, and 120 kPa. The permeate qualities of the hybrid processes were evaluated, and it was found that the integrated process with the 1 kDa MWCO UF membrane yielded the best water quality that falls within the US EPA reuse standard for boiler-feed and cooling water. It was also observed that the permeate quality is fit for extended reuse as process water in the cement, petroleum and coal industries. In addition, the hybrid system’s operation consumed 37.13 Wh m⁻³ of energy at the highest applied pressure of 120 kPa, which is far lesser than the typical energy requirement range (0.8–1.0 kWh m⁻³) for such wastewater reclamation.
Показать больше [+] Меньше [-]Risk element sorption/desorption characteristics of dry olive residue: a technique for the potential immobilization of risk elements in contaminated soils
2016
Hovorka, Miloš | Száková, Jiřina | García Sánchez, Mercedes | Acebal, Mercedes Blanc | García-Romera, Inmaculada | Tlustoš, Pavel
Olive oil production is one of the most relevant agroindustrial activities in the Mediterranean region and generates a huge amount of both solid and semi-solid wastes, the uncontrolled disposal of which might lead to serious environmental problems. Due to its organic matter and mineral nutrient content, the waste material can be applied to agricultural soil as a fertilizer. However, due to its high organic matter content, dry olive residue (DOR), commonly called “alperujo,” has the potential to immobilize risk elements in contaminated soils. The main objective of this study was to assess the possible effect of DOR on sorption of risk elements such as cadmium (Cd), lead (Pb), and zinc (Zn) in the soil. A set of batch sorption experiments were carried out to assess the ability of DOR to adsorb Cd, Pb, and Zn where the effect of the preceding biotransformation of DOR by four species of fungi: Penicillium chrysogenum, Coriolopsis floccosa, Bjerkhandera adusta, and Chondrostereum purpureum was compared. The Freundlich and Langmuir sorption isotherms were calculated to assess the sorption characteristics of both transformed and non-transformed DOR. The results showed good potential sorption capacity of DOR, especially for Pb and to a lesser extent for Cd and Zn. Better sorption characteristics were reported for the biotransformed DOR samples, which are expected to show higher humification of the organic matter. However, the desorption experiments showed weakness and instability of the DOR-bound elements, especially in the case of Zn. Thus, future research should aim to verify the DOR sorption pattern in contaminated soil as well as the potential stabilization of the DOR element bounds where the increase of the pH levels of the DOR samples needs to be taken into account.
Показать больше [+] Меньше [-]Assessment of arsenic in colostrum and cord serum and risk exposure to neonates from an island population in China
2016
Xu, Chenye | Tang, Mengling | Zhu, Siyu | Naranmandura, Hua | Liu, Weiping
Arsenic (As) has been proven to be highly toxic to humans, but limited attention has focused on exposure levels and potential risks to mother-neonate pairs of coastal populations. This study was conducted by examining the As concentration in colostrum and umbilical cord serum collected from 106 mother-neonate pairs living on Shengsi Island, facing the Yangtze River estuary and Hangzhou Bay in China. Average concentrations of total As in colostrum and cord serum were 18.51 ± 7.00 and 19.83 ± 10.50 μg L⁻¹. One-way ANOVA analysis showed delivered ages and source of drinking water played significant roles in influencing the maternal exposure patterns. Correlation analysis indicated a significantly positive association between As concentrations in colostrum and cord serum. Multivariable linear regression models adjusted for other confounders clarified the dose-response relationship with a coefficient value of 0.23 and a 95 % confidence interval of (0.006, 0.492); p < 0.05. The calculated daily intake of total As for neonates through breastfeeding was in the range from 0.413 to 3.65 μg kg⁻¹ body weight, and colostrum As, especially the most toxic species, inorganic arsenic (iAs), would pose a risk to neonates.
Показать больше [+] Меньше [-]POPs in a major conurbation in Turkey: ambient air concentrations, seasonal variation, inhalation and dermal exposure, and associated carcinogenic risks
2016
Ugranli, Tugba | Gungormus, Elif | Kavcar, Pınar | Demircioglu, Eylem | Odabasi, Mustafa | Sofuoglu, Sait C. | Lammel, Gerhard | Sofuoglu, Aysun
Semi-volatile organic compounds were monitored over a whole year, by collection of gas and particle phases every sixth day at a suburban site in Izmir, Turkey. Annual mean concentrations of 32 polychlorinated biphenyls (∑₃₂PCBs) and 14 polycyclic aromatic hydrocarbons (∑₁₄PAHs) were 348 pg/m³ and 36 ng/m³, respectively, while it was 273 pg/m³ for endosulfan, the dominant compound among 23 organochlorine pesticides (OCPs). Monte Carlo simulation was applied to the USEPA exposure-risk models for the estimation of the population exposure and carcinogenic risk probability distributions for heating and non-heating periods. The estimated population risks associated with dermal contact and inhalation routes to ∑₃₂PCBs, ∑₁₄PAHs, and some of the targeted OCPs (α-hexachlorocyclohexane (α-HCH), β-hexachlorocyclohexane (β-HCH), heptachlor, heptachlor epoxide, α-chlordane (α-CHL), γ-chlordane (γ-CHL), and p,p′-dichlorodiphenyltrichloroethane (p,p′-DDT)) were in the ranges of 1.86 × 10⁻¹⁶–7.29 × 10⁻⁹ and 1.38 × 10⁻¹⁰–4.07 × 10⁻⁶, respectively. The inhalation 95th percentile risks for ∑₃₂PCBs, ∑₁₄PAHs, and OCPs were about 6, 3, and 4–7 orders of magnitude higher than those of dermal route, respectively. The 95th percentile inhalation risk for ∑₃₂PCBs and OCPs in the non-heating period were 1.8- and 1.2–4.6 folds higher than in the heating period, respectively. In contrast, the 95th percentile risk levels for ∑₁₄PAHs in the heating period were 4.3 times greater than that of non-heating period for inhalation, respectively. While risk levels associated with exposure to PCBs and OCPs did not exceed the acceptable level of 1 × 10⁻⁶, it was exceeded for 47 % of the population associated with inhalation of PAHs with a maximum value of about 4 × 10⁻⁶.
Показать больше [+] Меньше [-]Isolation, purification, and identification of antialgal substances in green alga Ulva prolifera for antialgal activity against the common harmful red tide microalgae
2016
Sun, Ying-ying | Wang, Hui | Guo, Gan-lin | Pu, Yin-fang | Yan, Bin-lun | Wang, Chang-hai
Ten compounds (1~10) were successfully isolated from green algae Ulva prolifera through the combination of silica gel column chromatography, Sephadex LH-20 column chromatography and repeated preparative thin-layer chromatography. These ten compounds showed antialgal activity against red tide microalgae. Among them, compounds 3, 6, and 7 showed stronger antialgal activity against red tide microalgae. Furthermore, their structure was identified on the basis of spectroscopic data. There are three glycoglycerolipids: 1-O-octadecanoic acid-3-O-β-D-galactopyranosyl glycerol (2), 1-O-palmitoyl-3-O-β-D-galactopyranosyl glycerol (4), and 1-O-palmitoyl-2-O-oleoyl-3-O-β-D-galactopyranosyl glycerol (5); two monoglycerides: glycerol monopalmitate (1), 9-hexadecenoic acid, 2,3-dihydroxypropyl ester (3); two terpenoids: loliolide (6) and lsololiolide (7); one lipid-soluble pigments: zeaxanthin (8); one sterol: cholest-5-en-3-ol (9); and one alkaloid: pyrrolopiperazine-2,5-dione (10). These compounds were isolated from U. prolifera for the first time, and compounds 2, 3, 5, and 8 were isolated from marine macroalgae for the first time.
Показать больше [+] Меньше [-]