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Fluoride has strong electronegativity and exposes diversely in nature. Water fluoridation is the most pervasive form of occurrence, representing a significant threat to human health. In this study, we investigate the morphometric and physiological alterations triggered by fluoride stimulation during the embryogenesis of zebrafish and reveal its putative effects of stage- and/or dose-dependent. Fluoride exhibits potent biological activity and can be extensively absorbed by the yolk sac, exerting significant effects on the development of multiple organs. This is primarily manifested as restricted nutrient utilization and elevated levels of lipid peroxidation, further leading to the accumulation of superoxide in the yolk sac, liver, and intestines. Moreover, pericardial edema exerts pressure on the brain and eye development, resulting in spinal curvature and reduced body length. Besides, acute fluoride exposure with varying concentrations has led to diverse teratogenic outcomes. A low dose of water fluoridation tends to induce abnormal development of the embryonic yolk sac, while vascular malformation is widely observed in all fluoride-treated groups. The effect of fluoride exposure on blood circulation is universally present, even in zebrafish larvae that do not exhibit obvious deformities. Their swimming behavior is also affected by water fluoridation, resulting in reduced activity and delayed reactions. In conclusion, this study provides valuable insights into the monitoring of environmental quality related to water fluoridation and disease prevention., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Polycyclic aromatic hydrocarbons (PAHs) are significant environmental pollutant that can lead to cancer and endocrine system disrupting. Here we developed a real-time immuno-PCR (RT-IPCR) assay based on a biotinylated reporter DNA system for ultrasensitive detection of pyrene (PYR) and homologous PAHs in water. The PAHs in sample compete with PYR-OVA coated on PCR plate to bind with monoclonal antibody (McAb). The biotinylated goat anti-mouse IgG (Bio-IgG) can be captured by the McAb bound with PYR-OVA. Then streptavidin is bound with biotin on Bio-IgG. Finally biotinylated reporter DNA is captured by the streptavidin and quantified by real-time PCR using FastStart universal SYBR Green Master (ROX) kit. The linear range of the assay was from 500 fmol L(-1) to 5 nmol L(-)) with a detection limit of 450 fmol L(-1). The average recoveries of PYR and homologous PAHs from lake water, tap water and commercial mineral water were 96.8%, 101.4% and 99.6% respectively, indicating that water samples had little interfere with the assay. The results demonstrated that the developed RT-IPCR might be a potential method for ultrasensitive detection of PYR and homologous PAHs in drinking and environment water sample., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Laboratory experiments were carried out to understand the toxicology of pyrene in the goldfish Carassius auratus and investigate the potential oxidative stress induced by reactive oxygen species (ROS) in vivo in a time-dependent manner. Pyrene bioaccumulation, induction of reactive oxygen species and the consequent biochemical responses in the liver of the fish were examined. Fish were exposed to 0.05 mg/L pyrene for different periods. The pyrene concentration in fish liver was analyzed by high performance liquid chromatography (HPLC). Free radicals were detected by electron paramagnetic resonance (EPR). The activities of antioxidant enzymes, contents of nonenzymatic antioxidants and malondialdehyde (MDA) in fish liver were also determined. Results indicated that the pyrene concentrations in fish liver reached a maximum level on day 1, and then declined to a low steady state level over 7 days. The free radical significantly increased at 6 h and reached a maximum on day 2, while the superoxide dismutase (SOD) activity and MDA content were induced, and the reduced glutathione (GSH) content was inhibited by day 2. The catalase (CAT) and glutathione-S-transferase (GST) activities were significantly induced at 12 h. These results indicated that pyrene was rapidly bioaccumulated in fish resulting in redox cycling, and the production of free radical is an important mechanism of pyrene toxicity in C. auratus. The indicators of antioxidant system are sensitive and useful for the study of early biomarkers of pyrene exposure in fish.

In this study we report the production of a monoclonal antibody (Mab) specific for Cr(III)-chelate and the development of a competitive immunoassay for detection of Cr(III) in water samples. In the assay, the complete antigen (Cr(III)-ITCBE-BSA) was used as coating antigen, and Cr(III)-ITCBE as competitor competes with coating antigen to bind with Mab. Using this approach, the spiked water samples with Cr(III) were detected. The linear range of the detection was 0.7-12.4 ng mL(-1). The limit of the detection (LOD) was 0.51 ng mL(-1). The spiked results were also confirmed by ICP-MS, which showed a good correlation (R(2)=0.997) between the two methods. The results indicated that the developed assay was reliable and suitable for the detection of Cr(III) in water samples., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Some synthetic chemicals, which have been shown to disrupt thyroid hormone (TH) function, have been detected in surface waters and people have the potential to be exposed through water-drinking. Here, the presence of thyroid-active chemicals and their toxic potential in drinking water sources in Yangtze River Delta were investigated by use of instrumental analysis combined with cell-based reporter gene assay. A novel approach was developed to use Monte Carlo simulation, for evaluation of the potential risks of measured concentrations of TH agonists and antagonists and to determine the major contributors to observed thyroid receptor (TR) antagonist potency. None of the extracts exhibited TR agonist potency, while 12 of 14 water samples exhibited TR antagonistic potency. The most probable observed antagonist equivalents ranged from 1.4 to 5.6 µg di-n-butyl phthalate (DNBP)/L, which posed potential risk in water sources. Based on Monte Carlo simulation related mass balance analysis, DNBP accounted for 64.4% for the entire observed antagonist toxic unit in water sources, while diisobutyl phthalate (DIBP), di-n-octyl phthalate (DNOP) and di-2-ethylhexyl phthalate (DEHP) also contributed. The most probable observed equivalent and most probable relative potency (REP) derived from Monte Carlo simulation is useful for potency comparison and responsible chemicals screening.

Due to the surface reaction between zero-valent iron and Cr(VI), iron cannot be fully utilized in the Fe(0)-Permeable Reactive Barrier(PRB), and the PRB is prone to compaction and blockage. In order to resolve these problems, iron powder coated with different polymer was tested in the treatment of chromium-polluted groundwater. Experimental results demonstrated that sodium alginate (SA) was the best package materials. According to analysis with FEI and EDX, pore structures were created by cross-linking of SA with Ca2+, in which a lot of attaching points exist, and through which Cr(VI) could react with interior iron powder. SA coating cast iron (SAC) and reduced iron (SAR) were tested in the treatment of chromium-polluted groundwater individually; the results showed that the removal efficiency of Cr( VI) by SAC was double that by SAR. After optimization of technology parameters of SAC, the Cr(VI) removal process follows the pseudo first-order kinetics. Based on dynamic experiments with SAC, Cr(VI)/Fe(0) was up to 32.25 mg x g(-1) and the PRB maintained high permeability coefficient (2.38 cm x s(-1)) after complete reaction. Compared with cast iron media is feasible in the remediation of chromium contaminated groundwater.

Thyroid hormone disrupting compounds in water sources is a concern. Thyroid hormone (TH) agonist and antagonist activities of water sources from the Yangtze River, Huaihe River, Taihu Lake and ground water in the Yangtze River Delta region were evaluated by use of a TH reporter gene assay based on the green monkey kidney fibroblast (CV-1). While weak TH receptor (TR) agonist potency was observed in only one of 15 water sources, antagonist potency was present in most of the water sources. TR antagonist equivalents could be explained by the presence of dibutyl phthalate (DBP), with concentrations ranging from 2.8×10(1) to 1.6×10(3) μg DBP /L (ATR-EQ(50)s). None of the ground waters exhibited TH agonist potencies while all of the samples from Taihu Lake displayed notable TR antagonist potencies. To identify the responsible thyroid active compounds, instrumental analysis was conducted to measure a list of potential thyroid-disrupting chemicals, including organochlorine (OC) pesticides and phthalate esters. Combining the results of the instrumental analysis with those of the bioassay, DBP was determined to account for 17% to 144% of ATR-EQ(50)s in water sources. Furthermore, ATR-EQ(20-80) ranges for TR antagonist activities indicated that samples from locations WX-1 and WX-2 posed the greatest health concern and the associated uncertainty may warrant further investigation., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Mercury ions (Hg(II)) are considered highly toxic and hazardous element even at low levels. The contamination of Hg(II) is a global problem. To develop selective and sensitive technique for the detection of Hg(II) has attracted considerable attention. In this study, a multi-component chemically reactive detection conjugate for determination of Hg(II) has been synthesized and a competitive format assay was proposed. In the technique, the chemically reactive capture conjugate was coated on the plate. The reactive detection conjugate was then captured by the capture conjugate. TMB solution was added and catalyzed by HRP molecules immobilized on AuNPs. Finally, the developed enzymatic signal was measured at 450 nm. The linear range of the assay was 0.35-350 ppb with a detection limit of 0.1 ppb. The average recoveries of Hg(II) from mineral water, tap water and lake water were 100.03%, 103.13% and 102.03%, respectively. All coefficients of variation (CVs) were less than 10%. The results are closely correlated with those from inductively coupled plasma mass spectrometry (ICP-MS), which indicated that the developed technique is a reliable method for and sensitive detection of Hg(II) in water samples., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The detection of heavy metal ions using enzyme-linked immunosorbent assays (ELISA) has been reported by several research groups. However, highly sensitive and selective detection of total heavy metal ions using ELISA is a major technical limitation. Here we describe the development of a versatile and highly sensitive probe combining goat anti-mice IgG, colloidal gold nanoparticles (AuNPs) and horseradish peroxidase (HRP). We demonstrate the utility of this probe using three kinds of heavy metal complete antigens and three monoclonal antibodies (McAbs) in one ELISA system to establish a high-throughput screening protocol. The procedure was successfully applied to analysis of Hg(II), Pb(II) and Cd(II) individually and totally from different water samples. The sensitivities for the detection of Hg(II), Pb(II) and Cd(II) individually and totally are 27.4, 3.9, 15.8 and 18.2 nM, respectively. And all limit of detection (LODs) are lower than 1.2 nM. The recovery results obtained from the developed technique showed a good correlation (R(2)=0.983) with those from ICP-MS. The major advantage of the probe is the versatility and high sensibility. The probe could be potentially used, upon demand, as a sensitive and versatile detector for a broad range of applications., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Ruthenium-based catalysts were prepared by a saturation-dip method. Their catalytic activity was evaluated by a catalytic wet oxidation (CWO) process. The ruthenium-based catalysts were used to purify organic pharmaceutical wastewater with high concentration pyridine and pyridine derivatives that have high chemical oxygen demand (COD). In the CWO process, organic pharmaceutical wastewater was continuously pumped into fixed-bed reactors filled with Ru-based catalysts, while the organic components in wastewater were catalytically degraded by oxygen at high temperatures and pressures (temperature, 170-300 degrees C; pressure, 1.0-10 MPa). The experimental results showed that the prepared catalysts could effectively purify pharmaceutical wastewater with high concentration organic components, which are difficult to degrade biochemically, and that the removal rates of both COD and total nitrogen were over 99%.

In our previous study, electron paramagnetic resonance (EPR) evidence of reactive oxygen species (ROS) production in Carassius auratus following 2-chlorophenol (2-CP) administration was provided. To further investigate the potential pathway of ROS production, liver mitochondria of C. auratus was isolated and incubated with 2-CP for 30 min. An EPR analysis indicated ROS was produced, and intensities of ROS increased with increasing concentrations of 2-CP. The ROS was then assigned OH by comparing with Fenton reaction. Either catalase or superoxide dismutase, extinguished OH completely in the mitochondria mixture. These facts suggested that O2(.-) and H2O2 contributed to the formation of OH in mitochondria in C. auratus stressed by 2-CP. Combining previous references and our own data, it is reasonable to suggest that 2-CP is first oxidized by H2O2 present in vivo to form phenoxyl radical under the catalytic action of cellular peroxidase (1); phenoxyl radical oxidizes mitochondria NADH to NAD in the presence of NADH (2); NAD reacts with oxygen in vivo to produce O2(.-) (3); O2(.-) is spontaneously dismutated by SOD to form H2O2 and O2, which creates a renewable supply of H2O2 as the initiators of the chain reactions until NADH is consumed (4); simultaneously with reaction (4), O2(.-) reacts with H2O2 to form OH radical via the Haber-Weiss reaction (5). A strong negative correlation (r=-0.9278, p<0.01) between glutathione (GSH) pool and OH production was observed after fish were i.p. injected with 2-CP (250 mg kg(-1)), indicating the depletion of GSH caused by OH.

Wet vegetation performed different physiological actions under different pollution loads, thus inducing different purification effects on pollutants. Since water of various rivers, lakes and ponds are polluted at different extents and purification levels currently in China, a typical submerged vegetation, Vallisneria spiraslis L. is selected to study the purification effects on total nitrogen(TN) under different purification levels, which is widely distributed in rivers and lakes of Yangtz middle and down stream. The targets of this paper are to determine the nitrogen degradation impacts of Vallisneria spiraslis L., and nitrogen accumulation and distribution in leaf and root rules, and inorganic nitrogen conformation transformation characters under 7 nitrogen loads during 7 to 22 Sept., 2006. The 7 nitrogen loads are 1.0 mg/L, 5.0 mg/L, 10.0 mg/L, 20.0 mg/L, 40.0 mg/L, 60.0 mg/L and 80.0 mg/L. The experiment data show that Vallisneria spiraslis L. have significant effects on nitrogen purification while the TN concentration equal to and less than 60 mg/L, and the contribution principles of vegetation are similar among the 6 loads. Whereas, when the TN load bigger than 80.0 mg/L, Vallisneria spiraslis L. have no obvious contribution on nitrogen purification. Meanwhile, the nitrogen accumulation principles in the leaf and root of Vallisneria spiraslis L. is interrelated to the TN load. However, its distribution ratio in leaf to root is unrelated with TN load. Furthermore, the conformation of inorganic nitrogen transform characters changed with the TN load increasing. It is concluded that ammonia concentration decreased rapidly while the nitrogen load less than 20.0 mg/L, and the ammonia concentration ratio in the inorganic nitrogen increased remarkably with the nitrogen load increasing. Results indicate Vallisneria spiraslis L. have different purification contribution extents which can be benefit for nitrogen removal in different eutrophicated water and wet vegetation restoration.

Chromophoric dissolved organic matter (CDOM) represents the fraction of the dissolved organic pool which absorbs light in the visible as well as UV ranges. It could affect the color of the waters. It is necessary to study it during in research on ecosystem, remote sensing of the water color and the cycle of carbon in waters. CDOM can fluoresce when excited, so fluorescence spectrum has been used to study its origin, distribution, and change. In the present article the fluorescence spectrophotometer was used to study the relation between the fluorescence intensity, spectrum area and the concentration of CDOM. When the concentration of CDOM is low (less than 75 mg x L(-1)), there is a better linear relationship (r2 > 0.98) between the fluorescence intensity, the spectrum area and the concentration of CDOM. Meanwhile good linear relations were found between the fluorescence intensity and spectrum area, which showed the same changeable trend of the fluorescence intensity and spectrum area with the concentration change of CDOM. A method was established to quantify the concentration of CDOM in water from different source using the linear relationship between the spectrum area and the concentration. It suits the complicated constituent analysis of CDOM and could really and accurately show the concentration of CDOM in natural water.

Excitation-emission matrix spectroscopy (EEMs) was applied to measure the fluorescence properties of dissolved organic matter (DOM) in seawater collected from Jiaozhou Bay in June, 2005. The study areas include central Bay area, receptor areas of Dagu River, Licun River and Haibo River. The aim was to investigate the influence of discharges from several typical rivers to the receiving seawater. Dagu River discharges mostly freshwater, while the other two rivers discharges include more wastewaters from factories and sewages treatments. The results indicate that there is a redshift of the position of humic-like fluorescence peaks due to the discharges from sewages and wastewaters from factories. The intensities of protein-like and humic-like peaks were the strongest in the samples from area near Haibo River and Licun River, while the weakest fluorescence intensities of both protein-like and humic-like were observed in the samples collected from central bay area. This suggests that river inputs are the mains sources of DOM in seawater of Jiaozhou Bay, while DOM produced by bioactivity in situ dominates those in central Bay area. The relationships of protein-like and humic-like fluorescence intensities vary depending on the water samples. The DOM in seawater of Jiaozhou Bay may be polluted by protein-like organic matter produced by human activity, as indicated by higher ratios of protein-like and humic-like fluorescence intensities. The results suggest the potential utility of EEMs technique for trace DOM and land-based pollution sources.

Acute toxicity of BPA and TBBPA to Daphnia magna, zebrafish (Brachydanio rerio) and development effects of zebrafish embryo and zebrafish. The tested chemicals remarkably restrained the were studied, and safety assessment was also made to Daphnia magna mobilization of Daphnia magna, which may cause them death. 48 h EC50 values for D. magna were 8.91 and 0.69 mg x L(-1) respectively. In addition, the chemicals showed the toxicity effects on zebrafish, and 96 h LC50 values were 9.06 and 1.78 mg x L(-1) respectively. BPA and TBBPA remarkably retarded the development of zebrafish embryos, which may cause embryo abnormality and death. And the most sensitive toxicological endpoints to BPA and TBBPA were found, 72 h EC50 (malformation and embryo do not hatch) values were 2.90 and 0.14 mg x L(-1) respectively. The results showed that zebrafish embryo should be the most sensitive to the tested chemicals. The results indicated that BPA and TBBPA were the pollutants with high toxicity, in which TBBPA had the higher toxicity. BPA is a potential teratogen to zebrafish embryos, while TBBPA restrains embryo from hatch.

The effects of low level zinc(Zn2+)and its EDTA complex on zinc accumulation and antioxidant enzymes,such as catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPx) in the liver of Carassius auratus are studied after 40 day exposure. The results show that zinc accumulation is significantly increased with higher zinc concentration. When fish are exposed to Zn-EDTA, the zinc accumulation in the liver of fish increased slightly according to the control. SOD, GST, CAT and GPx activity all decrease with adding to Zn2+ and Zn-EDTA in waters. However, the decrease of CAT and GPx activities of fish liver are alleviated with the addition of EDTA. The GST activities increased at lower concentration solutions ( < 0.05mg-L(-1) ), however its activities were inhibited at higher Zn2 + solution ( > 0.05mgL- ). These results suggest that CAT and GPx are more sensitive to low zinc exposure than SOD and GST, and they can be served as biomarkers of low concentration zinc exposure in aquatic ecosystem.

Petroleum oil spill happens occasionally at sea. It's important to differentiate the exact products in order to carry out following actions to decrease harmfulness. In the present study, a rapid oil spill identification method by near infrared spectroscopy coupled with pattern recognition techniques is proposed. 56 simulated spilled oils of gasoline, diesel fuel and lubricating oil in marine were chosen to develop the method. Organic reagent of CCl4 was used to extract the oil. Pattern recognition techniques were established by principal component analysis (PCA) coupled with Mahalanobis' distance with the multiplicative signal correction (MSC) and Norris first derivative pretreatment. The study shows that PCA technique is a useful method to extract the main characteristics, and Mahalanobis' distance is an ellipsoidal boundary that circumscribes a data cluster. And oil spill samples with concentration above 0.4 microL x mL(-1) can be successfully identified by the method. The developed technique could be further applied to the identification of spilled oil in marine.