Overview of passive Chemcatcher sampling with SPE pretreatment suitable for the analysis of NPEOs and NPs

Effects of maternal exposure to nonylphenol on learning and memory in offspring involve inhibition of BDNF-PI3K/Akt signaling

Nonylphenol (NP), a global environmental pollutant, has been found to result in impairments of neurodevelopment. However, effects of maternal exposure to NP on learning and memory and the potential mechanisms are largely unexplored. Thus, we treated dams with NP during gestation and lactation to study its effect on learning and memory in offspring. Morris water maze (MWM) task and the electrophysiological recording in the hippocampus were conducted in pups. We also investigated the activation of BDNF-PI3K/Akt signaling and the expression of its target protein PSD-95 in offspring hippocampus, which are curial for the synaptic plasticity and learning and memory. The results showed that maternal exposure to NP led to poor performance in MWM task and especially impairments of long-term potentiation (LTP), although the termination of NP exposure was at the end of lactation. Meanwhile, maternal exposure to NP also decreased the activation of BDNF-PI3K/Akt signaling and the protein level of PSD-95. Taken together, our results support the hypothesis that maternal exposure to NP during gestation and lactation causes damages to learning and memory. In addition, suppressed activation of the BDNF-PI3K/Akt signaling may contribute to these impairments caused by maternal exposure to NP.

Procedures of determining organic trace compounds in municipal sewage sludge-a review

Sewage sludge is the largest by-product generated during the wastewater treatment process. Since large amounts of sludge are being produced, different ways of disposal have been introduced. One tempting option is to use it as fertilizer in agricultural fields due to its high contents of inorganic nutrients. This, however, can be limited by the amount of trace contaminants in the sewage sludge, containing a variety of microbiological pollutants and pathogens but also inorganic and organic contaminants. The bioavailability and the effects of trace contaminants on the microorganisms of soil are still largely unknown as well as their mixture effects. Therefore, there is a need to analyze the sludge to test its suitability before further use. In this article, a variety of sampling, pretreatment, extraction, and analysis methods have been reviewed. Additionally, different organic trace compounds often found in the sewage sludge and their methods of analysis have been compiled. In addition to traditional Soxhlet extraction, the most common extraction methods of organic contaminants in sludge include ultrasonic extraction (USE), supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), and pressurized liquid extraction (PLE) followed by instrumental analysis based on gas or liquid chromatography and mass spectrometry.

The role of passive sampling in monitoring the environmental impacts of produced water discharges from the Norwegian oil and gas industry

Stringent and periodic iteration of regulations related to the monitoring of chemical releases from the offshore oil and gas industry requires the use of ever changing, rapidly developing and technologically advancing techniques. Passive samplers play an important role in water column monitoring of produced water (PW) discharge to seawater under Norwegian regulation, where they are used to; i) measure aqueous concentrations of pollutants, ii) quantify the exposure of caged organisms and investigate PW dispersal, and iii) validate dispersal models. This article summarises current Norwegian water column monitoring practice and identifies research and methodological gaps for the use of passive samplers in monitoring. The main gaps are; i) the range of passive samplers used should be extended, ii) differences observed in absolute concentrations accumulated by passive samplers and organisms should be understood, and iii) the link between PW discharge concentrations and observed acute and sub-lethal ecotoxicological end points in organisms should be investigated.

Overview of the Chemcatcher® for the passive sampling of various pollutants in aquatic environments Part A: Principles, calibration, preparation and analysis of the sampler

The passive sampler Chemcatcher(®), which was developed in 2000, can be adapted for various types of water contaminants (e.g., trace metals, polycyclic aromatic hydrocarbons, pesticides and pharmaceutical residues) depending on the materials chosen for the receiving phase and the membrane. The Chemcatcher(®) has been used in numerous research articles in both laboratory experiments and field exposures, and here we review the state-of-the-art in applying this passive sampler. Part A of this review covers (1) the theory upon which the sampler is based (i.e., brief theory, calculation of water concentration, Performance and Reference Compounds), (2) the preparation of the device (i.e., sampler design, choice of the membrane and disk, mounting of the tool), and (3) calibration procedures (i.e., design of the calibration tank, tested parameters, sampling rates).

Characterization of five passive sampling devices for monitoring of pesticides in water

Five different passive sampler devices were characterized under laboratory conditions for measurement of 124 legacy and current used pesticides in water. In addition, passive sampler derived time-weighted average (TWA) concentrations were compared to time-integrated active sampling in the field. Sampling rates (RS) and passive sampler-water partition coefficients (KPW) were calculated for individual pesticides using silicone rubber (SR), polar organic chemical integrative sampler (POCIS)-A, POCIS-B, Chemcatcher(®) SDB-RPS and Chemcatcher(®) C18. The median RS (Lday(-1)) decreased as follows: SR (0.86)>POCIS-B (0.22)>POCIS-A (0.18)>Chemcatcher(®) SDB-RPS (0.05)>Chemcatcher(®) C18 (0.02), while the median logKPW (Lkg(-1)) decreased as follows: POCIS-B (4.78)>POCIS-A (4.56)>Chemcatcher(®) SDB-RPS (3.17)>SR (3.14)>Chemcatcher(®)C18 (2.71). The uptake of the selected compounds depended on their physicochemical properties, i.e. SR showed a better uptake for more hydrophobic compounds (log octanol-water partition coefficient (KOW)>5.3), whereas POCIS-A, POCIS-B and Chemcatcher(®) SDB-RPS were more suitable for hydrophilic compounds (logKOW<0.70). Overall, the comparison between passive sampler and time-integrated active sampler concentrations showed a good agreement and the tested passive samplers were suitable for capturing compounds with a wide range of KOW's in water.

Study of different Chemcatcher configurations in the monitoring of nonylphenol ethoxylates and nonylphenol in aquatic environment

The main aim of the European Union Water Framework Directive (WFD) (2000/60/EC) is to protect rivers, lakes, coastal waters and groundwaters (EC 2000). The implementation of the WFD requires monitoring the concentration levels of several priority pollutants such as nonylphenol ethoxylates (NPEOs) and nonylphenol (NP) in the area of EU. The present practices for determining the concentration levels of various pollutants are, in many respects, insufficient, and there is an urgent need to develop more cost-effective sampling methods. A passive sampling tool named Chemcatcher was tested for monitoring NPEOs and NP in aqueous media. These environmentally harmful substances have been widely used in different household and industrial applications, and they affect aquatic ecosystems, for example, by acting as endocrine disrupting compounds. The suitability of different receiving phases which were sulfonated styrene-divinylbenzene reversed phase polymer (SDB-RPS), standard styrene-divinyl benzene polymer (SDB-XC) and C-18 (octadecyl) was assessed in laboratory and field trials. The effect of a diffusion membrane on the accumulation of studied compounds was also investigated. The SDB-XC and C-18 receiving phases collected the NPEOs and NP most effectively. The water flow affected the accumulation factor of the studied substances in the field trials, and the water concentrations calculated using sampling rates were tenfold lower than those measured with conventional spot sampling. The concentration of the analytes in spot samples taken from the sampling sites might be higher because in that case, the particle-bound fraction is also measured. The NPEOs readily attach to suspended matter, and therefore, the total concentration of such compounds in water is much higher. Also, the spot samples were not taken daily but once a week, while the passive samplers collected the compounds continuously for 2- or 4-week time periods. This may cause differences when comparing the results of those two methods as well. Both techniques can be applied for monitoring the concentration levels at different sampling sites, but the calculated and measured analyte concentrations in surrounding water are not necessarily comparable with each other. More experiments are still needed to study the effect of hydrological issues and humic substances on the accumulation of chemicals. However, the Chemcatcher passive sampler gives valuable information about the mean concentration levels of studied compounds during 2- or 4-week sampling period. This is important for comparison of annual monitoring results, especially in sampling sites with rapidly fluctuating concentrations.

Rapid separations by LC using ion-exchange media based on spongy monoliths

Novel sponge-based monoliths containing ionic functional groups were developed for rapid separation and/or concentration of ionic solutes. The cationic and anionic spongy monoliths were prepared by chemical modifications of the pore surface on an original spongy monolith consisting of poly(ethylene-co-vinyl acetate). After hydrolysis of the spongy monolith, an anionic or a cationic moiety was introduced with succinyl chloride or acryloyl chloride/diethylamine, respectively. As a result of liquid chromatographic evaluations for the columns packed with these ionic spongy monoliths, both anionic and cationic monoliths showed ionic interactions with the opposing ionic solutes even if a higher flow rate (9.0 mL/min) was employed. Furthermore, we demonstrated the effective and rapid preconcentration of adenosine 5'-monophosphate in water using column-switching LC combined with the cationic spongy monolith as an online SPE adsorbent.