Carbamazepine (CBZ) is a pharmaceutical compound recalcitrant to conventional wastewater treatment plants and widely detected in wastewater bodies. In the present study, advanced oxidation processes ...for carbamazepine removal are investigated, with particular regard to the degradation pathways of carbamazepine by photoelectrocatalysis and conventional photocatalysis. Photoelectrocatalysis was carried out onto TiO2 meshes obtained by Plasma Electrolytic Oxidation, a well-known technique in the field of industrial surface treatments, in view of an easy scale-up of the process. By photoelectrocatalysis, 99% of carbamazepine was removed in 55 min while only 65% removal was achieved by photolysis. The investigation of the transformation products (TPs) was carried out by means of UPLC-QTOF/MS/MS. Several new TPs were identified and accordingly reaction pathways were proposed. Above 80 min the transformation products disappear, probably forming organic acids of low-molecular weight as final degradation products. The results demonstrated that photoelectrocatalysis onto TiO2 meshes obtained by plasma electrolytic oxidation is a useful alternative to common advanced oxidation processes as wastewater tertiary treatment aimed at removing compounds of emerging concern.
Endocrine disrupting compounds (EDCs) in the environment are considered a motif of concern, due to the widespread occurrence and potential adverse ecological and human health effects. The natural ...estrogen, 17β-estradiol (E2), is frequently detected in receiving water bodies after not being efficiently removed in conventional wastewater treatment plants (WWTPs), promoting a negative impact for both the aquatic ecosystem and human health. In this study, the biodegradation of E2 by
sp. ED55, a bacterial strain isolated from sediments of a discharge point of WWTP in Coloane, Macau, was investigated.
sp. ED55 was able to completely degrade 5 mg/L of E2 in 4 h in a synthetic medium. A similar degradation pattern was observed when the bacterial strain was used in wastewater collected from a WWTP, where a significant improvement in the degradation of the compound occurred. The detection and identification of 17 metabolites was achieved by means of UPLC/ESI/HRMS, which proposed a degradation pathway of E2. The acute test with luminescent marine bacterium
revealed the elimination of the toxicity of the treated effluent and the standardized yeast estrogenic (S-YES) assay with the recombinant strain of
revealed a decrease in the estrogenic activity of wastewater samples after biodegradation.
Diclofenac (DCF) is one of the most detected pharmaceuticals in environmental water matrices and is known to be recalcitrant to conventional wastewater treatment plants. In this study, degradation of ...DCF was performed in water by photolysis and photocatalysis using a new synthetized photocatalyst based on hydroxyapatite and TiO₂ (HApTi). A degradation of 95% of the target compound was achieved in 24 h by a photocatalytic treatment employing the HApTi catalyst in comparison to only 60% removal by the photolytic process. The investigation of photo-transformation products was performed by means of UPLC-QTOF/MS/MS, and for 14 detected compounds in samples collected during treatment with HApTi, the chemical structure was proposed. The determination of transformation product (TP) toxicity was performed by using different assays:
acute toxicity test, Toxi-ChromoTest, and
and
germination inhibition test. Overall, the toxicity of the samples obtained from the photocatalytic experiment with HApTi decreased at the end of the treatment, showing the potential applicability of the catalyst for the removal of diclofenac and the detoxification of water matrices.
Sediment toxicity plays a fundamental role in the health of inland fish communities; however, the assessment of the hazard potential of contaminated sediments is not a common objective in ...environmental diagnostics or remediation. This study examined the potential of transcriptional endpoints investigated in zebrafish (
Danio rerio
) exposed to riverbed sediments in ecotoxicity testing. Embryo-larval 10-day tests were conducted on sediment samples collected from five sites (one upstream and four downstream of the city of Milan) along a polluted tributary of the Po River, the Lambro River. Sediment chemistry showed a progressive downstream deterioration in river quality, so that the final sampling site showed up to eight times higher concentrations of, for example, triclosan, galaxolide, PAH, PCB, BPA, Ni, and Pb, compared with the uppermost site. The embryo/larval tests showed widespread toxicity although the middle river sections evidenced worse effects, as evidenced by delayed embryo development, hatching rate, larval survival, and growth. At the mRNA transcript level, the genes encoding biotransformation enzymes (
cyp1a
,
gst
,
ugt
) showed increasing upregulations after exposure to sediment from further downstream sites. The genes involved in antioxidant responses (
sod
,
gpx
) suggested that more critical conditions may be present at downstream sites, but even upstream of Milan there seemed to be some level of oxidative stress. Indirect evidences of potential apoptotic activity (
bcl2/bax
< 1) in turn suggested the possibility of genotoxic effects. The genes encoding for estrogen receptors (
erα
,
erβ1
,
erβ2
) showed exposure to (xeno)estrogens with a progressive increase after exposure to sediments from downstream sites, paralleled by a corresponding downregulation of the
ar
gene, likely related to antiandrogenic compounds. Multiple levels of thyroid disruption were also evident particularly in downstream zebrafish, as for thyroid growth (
nkx2.1
), hormone synthesis and transport (
tg
,
ttr
,
d2
), and signal transduction (
trα
,
trβ
). The inhibition of the
igf2
gene reasonably reflected larval growth inhibitions. Although none of the sediment chemicals could singly explain fish responses, principal component analysis suggested a good correlation between gene transcripts and the overall trend of contamination. Thus, the combined impacts from known and unknown covarying chemicals were proposed as the most probable explanation of fish responses. In summary, transcriptional endpoints applied to zebrafish embryo/larval test can provide sensitive, comprehensive, and timeliness information which may greatly enable the assessment of the hazard potential of sediments to fish, complementing morphological endpoints and being potentially predictive of longer studies.
► The peroxymonosulfate/Co(II) system effectively removed a non-ionic surfactant from aqueous solution. ► Sulfate radicals were the dominant radical species in the investigated system. ► Oxidation ...by-products were identified and degradation pathways for non-ionic surfactants were outlined.
The non-ionic surfactant Brij 35 was effectively removed from concentrated aqueous solution by the peroxymonosulfate/Co(II) system, using oxone (2KHSO
5·KHSO
4·K
2SO
4) as a source of peroxymonosulfate. At pH
=
2.3 and initial Brij 35 concentration in the range 680–2410
mg
L
−1, 86–94% removal was achieved after 24
h, using Co(II)
=
15
μM and oxone
=
5.9
mM. The effectiveness of removal did not change when initial pH was in the range 2.3–8.2. After five subsequent additions of Co(II) and oxone to the solution, COD and TOC removals increased up to 64% and 33%, respectively. Radical quenching tests confirmed that sulfate radical was the dominant radical species in the system. The main identified by-products from surfactant degradation were: (a) low molecular weight organic acids; (b) aldehydes and formates with shorter ethoxy chain than Brij 35; (c) alcohol ethoxylates carrying hydroxyl groups bonded to ethoxy chain. By-products identification allowed to hypothesize the pathways of Brij 35 degradation.
The photocatalytic efficiency of an innovative UV-light catalyst consisting of a mesoporous TiO2 coating on glass fibers was investigated for the degradation of pharmaceuticals (PhACs) in wastewater ...effluents. Photocatalytic activity of the synthesized material was tested, for the first time, on a secondary wastewater effluent spiked with nine PhACs and the results were compared with the photolysis used as a benchmark treatment. Replicate experiments were performed in a flow reactor equipped with a UV radiation source emitting at 254 nm. Interestingly, the novel photocatalyst led to the increase of the degradation of carbamazepine and trimethoprim (about 2.2 times faster than the photolysis). Several transformation products (TPs) resulting from both the spiked PhACs and the compounds naturally occurring in the secondary wastewater effluent were identified through UPLC-QTOF/MS/MS. Some of them, produced mainly from carbamazepine and trimethoprim, were still present at the end of the photolytic treatment, while they were completely or partially removed by the photocatalytic treatment.
•The River Lambro sediments contain AhR and ER agonists, and likely AR antagonists.•Exposing 50-dph barbel to sediments for 7 months induced gonadal histopathologies.•PBDE were the main responsible ...for thyroidal disruption.•Polar PAH, PBDE, PCB and estrogens induced DNA adducts and liver vacuolization.•Sediment transport to the River Po threatens native fish for tens of kilometres.
Juveniles (50 days post hatch) of a native cyprinid fish (Barbus plebejus) were exposed for 7 months to sediments from the River Lambro, a polluted tributary impairing the quality of the River Po for tens of kilometers from their confluence. Sediments were collected upstream of the city of Milan and downstream at the closure of the drainage basin of the River Lambro. Chemical analyses revealed the presence of a complex mixture of bioavailable endocrine-active chemicals, with higher exposure levels in the downstream section of the tributary. Mainly characterized by brominated flame retardants, alkylphenols, polychlorinated biphenyls, and minor co-occurring personal care products and natural hormones, the sediment contamination induced reproductive disorders, as well as other forms of endocrine disruption and toxicity. In particular, exposed male barbel exhibited higher biliary PAH-like metabolites, overexpression of the cyp1a gene, vitellogenin production in all specimens, the presence of oocytes (up to 22% intersex), degenerative alterations in their testis, liver fat vacuolization, a marked depression of total thyroxine (T4) and triiodothyronine (T3) plasma levels, and genotoxic damages determined as hepatic DNA adducts. These results clearly demonstrate that Lambro sediments alone are responsible for recognizable changes in the structure and function of the reproductive and, in general, the endocrine system of a native fish species. In the real environment, exposure to waterborne and food-web sources of chemicals are responsible for additional toxic loads, and the present findings thus provide evidence for a causal role of this tributary in the severe decline observed in barbel in recent decades and raise concern that the fish community of the River Po is exposed to endocrine-mediated health effects along tens of kilometres of its course.
The effectiveness of adding compost and the plant Medicago sativa in improving the quality of a soil historically contaminated by polychlorinated biphenyls (PCBs) was tested in greenhouse microcosms. ...Plant pots, containing soil samples from an area contaminated by PCBs, were treated with the compost and the plant, separately or together. Moreover, un-treated and un-planted microcosms were used as controls. At fixed times (1, 133 and 224 days), PCBs were analysed and the structure (cell abundance, phylogenetic characterization) and functioning (cell viability, dehydrogenase activity) of the natural microbial community were also measured. The results showed the effectiveness of the compost and plant in increasing the microbial activity, cell viability, and bacteria/fungi ratio, and in decreasing the amount of higher-chlorinated PCBs. Moreover, a higher number of α-Proteobacteria, one of the main bacterial groups involved in the degradation of PCBs, was found in the compost and plant co-presence.
Abstract
Non-target analysis (NTA) employing high-resolution mass spectrometry is a commonly applied approach for the detection of novel chemicals of emerging concern in complex environmental ...samples. NTA typically results in large and information-rich datasets that require computer aided (ideally automated) strategies for their processing and interpretation. Such strategies do however raise the challenge of reproducibility between and within different processing workflows. An effective strategy to mitigate such problems is the implementation of inter-laboratory studies (ILS) with the aim to evaluate different workflows and agree on harmonized/standardized quality control procedures. Here we present the data generated during such an ILS. This study was organized through the Norman Network and included 21 participants from 11 countries. A set of samples based on the passive sampling of drinking water pre and post treatment was shipped to all the participating laboratories for analysis, using one pre-defined method and one locally (i.e. in-house) developed method. The data generated represents a valuable resource (i.e. benchmark) for future developments of algorithms and workflows for NTA experiments.
This study investigated the environmental contamination of groundwater as a consequence of the discharge of treated wastewater into the soil. The investigation focused on a wastewater treatment plant ...located in an area fractured by karst in the Salento peninsula (Apulia, Italy). Water samples were collected at four sites (raw wastewater, treated wastewater, infiltration trench, and monitoring well), monthly from May to December 2019 (with the exception of August), and were tested for (1) panel of bacteria; (2) enteric viruses; and (3) chemical substances. A gradual reduction in the concentration of bacteria, viruses and contaminants of emerging concern was observed across the profile of soil fissured by karst. All monitored bacteria were absent from the monitoring well, except for
. Pepper mild mottle virus and adenovirus were detected at all sampling sites. Personal care products and X-ray contrast media showed the greatest decrease in concentration from infiltration trench to the monitoring well, while the highest residual concentrations in the monitoring well were found for anticonvulsants (78.5%), antimicrobials (41.3%), and antipsychotic drugs (38.6%). Our results show that parameters provided by current law may not always be sufficient to evaluate the sanitary risk relating to the discharge of treated wastewater to the soil.
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