The last 50 years of organic contamination of a highly anthropized tributary of the Po River (Italy).

We examined the temporal profiles of many organic micropollutants analysed in a sediment core sampled from a highly anthropized tributary of the Po River, the Lambro River. Analysed for extractable organic halogens (EOX), total petroleum hydrocarbons (C10-C40TPH), polycyclic aromatic hydrocarbons (PAHs), common legacy pollutants (DDTs, PCBs), halogenated flame retardants (PBDEs, DBDPE, TBBPA-bis, TCBPA, TBBPA, HBCDs), organotins (TBT, TPhT), antimicrobials (TCS, TCC), fragrances (AHTN, HHCB) and phthalates (DMP, DEP, DnBP, BBP, DEHP, DnOP), the dated sediment core revealed the historical record of 50 years of chemical contamination discharged into the Lambro and thereby the Po River. In this regard, the peak levels of PCBs and DDTs found in Lambro sediments were also identified in other sediment cores collected from the Po River prodelta in the Adriatic Sea, thus hundreds of kilometres downstream (Combi et al., 2020). The highest risk to aquatic organisms was associated with decades of high levels of C10-C40 TPH, PBDEs, PCBs, PAHs, DDTs, EOX, TCC, AHTN and DEHP, which in different periods of the contamination history, showed exceedances of guideline/threshold values. C10-C40 TPH and TCC, for example, were very high in the 1960s, whereas PCBs, DDTs, and PBDEs, peaked from the 1980s onward. The corresponding sums of PEC quotients ranged between 0.48 and 28.63, with a mean value (±SD) for the entire recording period of 10.62 ± 9.83. Environmental legislations and improved wastewater treatments were the main drivers of the recent downward trends observed for most of the chemicals investigated. Floods in turn resulted in macroscopic yet temporary improvements in the chemical quality of the tributary, conveying contaminated sediments into the Po River.

PBDE, HBCD, and novel brominated flame retardant contamination in sediments from Lake Maggiore (Northern Italy).

The reduction in the use of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) has opened the way for the introduction of novel brominated flame retardants (NBFRs) in place of the banned formulations. Important representatives of this group are decabromodiphenyl ethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), hexabromobenzene (HBB), and pentabromoethylbenzene (PBEB). In this study, the contamination due to NBRFs was investigated for the first time in Italy in the sediments of Lake Maggiore. The aim of the research was to characterize in detail the possible presence of temporal trends and/or to identify potential sources of contamination. The study also considered the PBDE and HBCD lake sediment's current contamination. The analytical results showed that sediments in Lake Maggiore and its tributary rivers had weak concentrations of PBEB, HBB, and BTBPE, but they did not have a negligible/insignificant contamination of HBCD (up to 23.7 ng/g dry weight (d.w.)). The determination of PBDEs in sediments showed that BDE-209 was the predominant congener (up to 217 and 28 ng/g d.w. in river and lake sediments, respectively). DBDPE was detected in the sediments with relevant concentrations (up to 280 ng/g d.w in the River Boesio sediments). The positive correlation of DBDPE with BDE-209 confirmed the wide and important use of this compound in the Lake Maggiore basin and the hypothesis that this compound will soon become one of the most important NBFRs used in Northern Italy. The contamination of Lake Maggiore sediments due to PBDEs, HBCD, and NBFRs were comparable to other worldwide situations.

What is in the fish? Collaborative trial in suspect and non-target screening of organic micropollutants using LC- and GC-HRMS.

A collaborative trial involving 16 participants from nine European countries was conducted within the NORMAN network in efforts to harmonise suspect and non-target screening of environmental contaminants in whole fish samples of bream (Abramis brama). Participants were provided with freeze-dried, homogenised fish samples from a contaminated and a reference site, extracts (spiked and non-spiked) and reference sample preparation protocols for liquid chromatography (LC) and gas chromatography (GC) coupled to high resolution mass spectrometry (HRMS). Participants extracted fish samples using their in-house sample preparation method and/or the protocol provided. Participants correctly identified 9-69 % of spiked compounds using LC-HRMS and 20-60 % of spiked compounds using GC-HRMS. From the contaminated site, suspect screening with participants' own suspect lists led to putative identification of on average ∼145 and ∼20 unique features per participant using LC-HRMS and GC-HRMS, respectively, while non-target screening identified on average ∼42 and ∼56 unique features per participant using LC-HRMS and GC-HRMS, respectively. Within the same sub-group of sample preparation method, only a few features were identified by at least two participants in suspect screening (16 features using LC-HRMS, 0 features using GC-HRMS) and non-target screening (0 features using LC-HRMS, 2 features using GC-HRMS). The compounds identified had log octanol/water partition coefficient (KOW) values from -9.9 to 16 and mass-to-charge ratios (m/z) of 68 to 761 (LC-HRMS and GC-HRMS). A significant linear trend was found between log KOW and m/z for the GC-HRMS data. Overall, these findings indicate that differences in screening results are mainly due to the data analysis workflows used by different participants. Further work is needed to harmonise the results obtained when applying suspect and non-target screening approaches to environmental biota samples.

Suspect screening of wastewaters to trace anti-COVID-19 drugs: Potential adverse effects on aquatic environment.

During the first period of the SARS-CoV-2 pandemic, the lack of specific therapeutic treatments led to the provisional use of a number of drugs, with a continuous review of health protocols when new scientific evidence emerged. The management of this emergency sanitary situation could not take care of the possible indirect adverse effects on the environment, such as the release of a large amount of pharmaceuticals from wastewater treatment plants. The massive use of drugs, which were never used so widely until then, implied new risks for the aquatic environment. In this study, a suspect screening approach using Liquid Chromatography-High Resolution Mass Spectrometry techniques, allowed us to survey the presence of pharmaceuticals used for COVID-19 treatment in three WWTPs of Lombardy region, where the first European cluster of SARS-CoV-2 cases was detected. Starting from a list of sixty-three suspect compounds used against COVID-19 (including some metabolites and transformation products), six compounds were fully identified and monitored together with other target analytes, mainly pharmaceuticals of common use. A monthly monitoring campaign was conducted in a WWTP from April to December 2020 and the temporal trends of some anti-COVID-19 drugs were positively correlated with those of COVID-19 cases and deaths. The comparison of the average emission loads among the three WWTPs evidenced that the highest loads of hydroxychloroquine, azithromycin and ciprofloxacin were measured in the WWTP which received the sewages from a hospital specializing in the treatment of COVID-19 patients. The monitoring of the receiving water bodies evidenced the presence of eight compounds of high ecological concern, whose risk was assessed in terms of toxicity and the possibility of inducing antibiotic and viral resistance. The results clearly showed that the enhanced, but not completely justified, use of ciprofloxacin and azithromycin represented a risk for antibiotic resistance in the aquatic ecosystems.

Integrated Exposure and Algal Ecotoxicological Assessments of Effluents from Secondary and Advanced-Tertiary Wastewater-Treatment Plants.

The great concern over the environmental impact of wastewaters has led to the designing of advanced treatment processes to upgrade conventional treatment plants and achieve a significant reduction of contaminants in receiving waters. In the present study we combined chemical and ecotoxicological analyses, aiming to evaluate the reduction of toxicity effects associated with the removal of micropollutants and to define the contribution of the detected compounds to the overall toxicity of the mixtures in a series of wastewater effluents collected from a secondary treatment (OUT 2) and from a tertiary activated carbon treatment (OUT 3) plant. The target compounds were selected after a screening procedure among pharmaceuticals, musk fragrances, and trace metals. The classical algal growth inhibition test was conducted on the original effluent samples and on different fractions obtained by solid-phase extraction (SPE) treatment. A good accordance was found between the removal of toxicity (30%-80%) and organic compounds (70%-80%) after the tertiary treatment, suggesting its high efficiency to improve the wastewater quality. The discrepancy between the contribution to the overall toxicity of the nonadsorbable compounds (i.e., inorganic or very polar organic compounds) as experimentally measured by the SPE bioassays (18%-76%) and calculated by the concentration addition approach (>97%) could be mitigated by including the bioavailability correction in metal-toxicity modeling of wastewater mixtures. For the organic compounds, the toxic equivalency method enabled us to quantify the portion of toxicity explained by the detected chemicals in both OUT 2 (82%-104%) and OUT 3 (5%-57%), validating the selection of the target molecules. The applied integrating approach could be implemented by the inclusion of both additional target chemicals and toxicity endpoints. Environ Toxicol Chem 2022;41:2404-2419. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Mercury Bioaccumulation in Benthic Invertebrates: From Riverine Sediments to Higher Trophic Levels.

Riverine sediments are important sites of mercury methylation and benthic invertebrates may be indicators of Hg exposure to higher organisms. From 2014 to 2018, sediments and invertebrates were collected along a mercury gradient in the Toce River (Northern Italy) and analyzed for THg and MeHg. Concentrations in invertebrates, separated according to taxon and to Functional Feeding Group, ranged from 20 to 253 µg kg-1 dry weight (d.w.) for THg, increasing from grazers (Leuctra, Baetis, Serratella) to predators (Perla). MeHg ranged from 3 to 88 µg kg-1 d.w. in biota, representing 6-53% of THg, while in sediments it was mostly below LOD (0.7 µg kg-1), accounting for ≤3.8% of THg. The Biota-Sediment Accumulation Factor (BSAF, ranging 0.2-4.6) showed an inverse relation to exposure concentrations (THg in sediments, ranging 0.014-0.403 µg kg-1 d.w.) and to organic carbon. THg in invertebrates (up to 73 µg kg-1 wet weight), i.e., at the basal levels of the aquatic trophic chain, exceeded the European Environmental Quality Standard for biota (20 µg kg-1 w.w.), posing potential risks for top predators. Concentrations in adult insects were close to those in aquatic stages, proving active mercury transfer even to terrestrial food chains.

Methylmercury determination in freshwater biota and sediments: Static headspace GC-MS compared to direct mercury analyzer.

We developed and compared two analytical methods for determination of MeHg in freshwater biota and sediments, by: I) simplified static headspace GC-MS using internal standard (IS) isotope dilution quantification, after microwave acid digestion and aqueous phase NaBEt4 ethylation; II) Automated Mercury Analyzer, after double toluene extraction followed by back-extraction with L-cystein. The performance was evaluated by analysis of certified reference materials. For biota, mean recovery was 100 ± 2% and relative standard deviation (RSD) ≤ 6.8% for method I, and mean recovery was 98 ± 7% and RSD ≤13% for method II. For sediments, recovery of 94.5% and RSD of 8.8% were obtained with method I, and recovery of 90.3% and RSD of 9.4% with method II. Limits of detection (LOD) were 0.7 µg kg-1 and 6 µg kg-1, respectively. Both techniques were tested for MeHg analysis in freshwater invertebrates, fish and sediments, covering a large range of MeHg values (1.9-670 µg kg-1 d.w.). • Both protocols proved to be suitable for MeHg analysis in complex environmental matrices, even if, for method II, interferences in the extraction phase and limited sensitivity may hinder sediment analysis. • Passing-Bablock regression revealed a slight disproportion between methods, with line slope = 1.058 (95% CI ranging from 1.001 to 1.090).

Twenty-year sediment contamination trends in some tributaries of Lake Maggiore (Northern Italy): relation with anthropogenic factors.

Lake tributaries collect contaminants from the watershed, which may accumulate in lake sediments over time and may be removed through the outlets. DDx, PCB, PAH, PBDE, and trace element (Hg, As, Cd, Ni, Cu, Pb) contamination was analyzed over 2001-2018 period in sediments of the 5 main tributaries and of the outlet of Lake Maggiore (Northern Italy). Sediment cores were collected in two points of the lake, covering 1995-2017 period. Concentrations were compared to Sediment Quality Guidelines (PECs), potential sources and drivers (land use, population numbers, industrial activities, hydrology) were analyzed, and temporal trends were calculated (Mann-Kendall test). PCB, PBDE, Pb, Cd, and Hg contamination derives mainly from heavy urbanization and industry. Cu and Pb show a temporal decreasing trend in the basin, likely as result of improved wastewater treatments and change in use. A recent PAH increase in the whole lake may derive from a single point source. A legacy DDx and Hg industrial pollution is still present, due to high persistence in sediments. Values of DDx, Hg, Pb, and Cu above the PECs in lake sediments and/or in the outlet show potential risk for aquatic organisms. Results highlight the key role of tributaries in driving contamination from the watershed to the lake through sediment transport.

Inter-laboratory mass spectrometry dataset based on passive sampling of drinking water for non-target analysis.

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.

Embryo/larval toxicity and transcriptional effects in zebrafish (Danio rerio) exposed to endocrine active riverbed sediments.

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, erß1, erß2) 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, trß). 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.

Presence and infectivity of SARS-CoV-2 virus in wastewaters and rivers.

The presence of SARS-CoV-2 in raw wastewaters has been demonstrated in many countries affected by this pandemic. Nevertheless, virus presence and infectivity in treated wastewaters, but also in the receiving water bodies are still poorly investigated. In this study, raw and treated samples from three wastewater treatment plants, and three river samples within the Milano Metropolitan Area, Italy, were surveyed for SARS-CoV-2 RNA detection by means of real time RT-PCR and infectivity test on culture cells. SARS-CoV-2 RNA was detected in raw, but not in treated wastewaters (four and two samples, respectively, sampled in two dates). The isolated virus genome was sequenced, and belonged to the strain most spread in Europe and similar to another found in the same region. RNA presence in raw wastewater samples decreased after eight days, probably following the epidemiological trend estimated for the area. Virus infectivity was always null, indicating the natural decay of viral pathogenicity in time from emission. Samples from receiving rivers (three sites, sampled in the same dates as wastewaters) showed in some cases a positivity to real time RT-PCR, probably due to non-treated, or inefficiently treated discharges, or to the combined sewage overflows. Nevertheless, also for rivers infectivity was null. Risks for public health should be limited, although a precautionary approach to risk assessment is here advocated, giving the preliminary nature of the presented data.

Polybrominated diphenyl ethers (PBDEs) in gammarids, caddisflies, and bed sediments of the lowland River Po.

Polybrominated diphenyl ethers (PBDEs) were investigated in sediments and invertebrates (gammarids and caddisflies) collected in the River Po, upstream and downstream from a polluted tributary. Besides a diffuse contamination by penta-BDE technical mixture, the river sediments identified the tributary as an important source to the main river of decabromodiphenyl ether (BDE-209), which peaked to 64 microg/g (OC) in the downstream stretch. At 10 km downstream from the tributary, a higher bioavailability was evident than at 22 km, and small gammarids accumulated at two/three times the levels of PBDEs found in large gammarids. The congener profiles of sediments and invertebrates were dominated by BDE-47, BDE-99 and BDE-209.

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in 0+ juvenile cyprinids and sediments of the Po River.

PBDE and PCB content has been determined in 0+ bleak (Cyprinus alburnus), nase (Chondrostoma soetta), gudgeon (Cyprinus gobio), chub (Cyprinus cephalus), and barbel (Barbus sp.) as well as in bed sediments sampled from the River Po upstream and downstream of the confluence of a tributary draining a highly industrialized and urbanized subbasin. Both groups of chemicals were present at higher levels in fish and sediments downstream from the confluence. In addition, whole-body concentrations of PBDEs and PCBs were different among species despite the young specimen age. The fact that PBDEs and PCBs were higher in benthivorous versus planktivorous fish, as well as in carnivorous versus herbivorous species, suggests that feeding behavior is a major controlling factor that may help differentiate the accumulation levels of 0+ juveniles. Of the five species, the pelagic/planktivorous cyprinid bleak (C. alburnus) showed the lowest concentrations (111 ng PBDE/g lipid weight [l.w.], 2016 ng PCB/g l.w.), whereas the benthic dweller and feeder barbel (Barbus sp.) had the highest concentrations of both groups of chemicals (259 ng PBDE/g l.w., 4785 ng PCB/g l.w.). The rank order of species contamination was essentially stable upstream and downstream from the tributary, and the congener contribution of PBDEs was also similar. In general, BDE-47 was the dominant congener, followed by BDE-100, -154, -153, and -28. BDE-209 dominated the PBDE congener profiles of sediments but was not found in any fish sample. Conversely, an unidentified hexa-BDE congener, which was not detected in sediments, was found in all fish species. The levels of PBDEs and PCBs determined in adult goby (Padogobius martensii), a small demersal predator also examined in the same river stretches, provided additional useful insights with which to interpret results.

The accumulation levels of PAHs, PCBs and DDTs are related in an inverse way to the size of a benthic amphipod (Echinogammarus stammeri Karaman) in the River Po.

The accumulation of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and DDTs were investigated in gammarids captured at three sites along the middle River Po; the first was located upstream and the other two were at increasing distances downstream of the confluence of a polluted tributary, the River Lambro. Using a GC-MS technique, the levels of PCBs, PAHs and DDTs were determined separately in large and small gammarids as well as in the fine fraction of sediment samples collected along the sites of capture. Results confirm the River Lambro as a source of these chemicals to the River Po, and show that bioaccumulation differences exist between small and large individuals, the former being more contaminated particularly by PCBs and DDTs. This is likely the result of several interacting factors such as contaminant bioavailability, gammarid-size effects on kinetic parameters and feeding selectivity. The bioaccumulation patterns of PCBs and DDTs, and their higher biota-sediment accumulation factors (BSAF), are consistent with chemical properties and suggest a dietary disequilibrium found only 10 km downstream from the tributary, and in smaller amphipods. Present results show that gammarids may represent an additional source of contaminants, particularly of chlorinated compounds, to the many organisms feeding on them, with a higher risk for those which prey selectively on smaller gammarids.

Improvements in the analysis of decabromodiphenyl ether using on-column injection and electron-capture detection.

During the development of a method to determine polybrominated diphenyl ethers (PBDEs) using GC/MS-MS equipped with a programmed temperature vaporizer (PTV) injector, a dramatic decrease in sensitivity to decabromodiphenyl ether (BDE-209) occurred and lack of sensitivity and repeatability was observed. An alternative method using GC/ECD equipped with an on-column injector was evaluated for this congener optimizing pre-column and column length. A coated retention gap (50 cm of length, 0.53 mm I.D., 0.15 microm d(f)) connected to a short capillary column (7 m of length, 0.32 mm I.D., 0.25 microm d(f)) showed the better sensitivity and repeatability. Finally, a double system based on the programmed temperature vaporizer injector/MS detector (for tri- to hepta-BDEs) and on-column injector/electron-capture detector (for BDE-209) was evaluated using two candidate certified materials (fish muscle tissue and river sediment).

POP and PAH contamination in the southern slopes of Mt. Everest (Himalaya, Nepal): Long-range atmospheric transport, glacier shrinkage, or local impact of tourism?

Due to their physico-chemical properties, POPs and PAHs are subjected to long-range atmospheric transport (LRAT) and may be deposited in remote areas. In this study, the contamination with DDx, PCBs, PBDEs, and PAHs was investigated in sediments and soils collected on the southern slopes of Mt. Everest (Himalaya, Nepal) in two different sampling campaigns (2008 and 2012). The results showed a limited contamination with POPs and PAHs in both soil and sediment samples. Therefore, the southern slopes of Mt. Everest can be considered a remote area in almost pristine condition. The LRAT mechanism confirmed its primary role in the transfer of contaminants to remote regions, while the gradual melting of glaciers, due to global warming, and the subsequent release of contaminants was suggested to be a secondary source of pollution of the lake sediments. In addition, the increase of tourism in this area during the last decades might have influenced the present concentrations of PAHs in the sediments and soils.

In situ bioavailability of DDT and Hg in sediments of the Toce River (Lake Maggiore basin, Northern Italy): accumulation in benthic invertebrates and passive samplers.

DDT and mercury (Hg) contamination in the Toce River (Northern Italy) was caused by a factory producing technical DDT and using a mercury-cell chlor-alkali plant. In this study, DDT and Hg contamination and bioavailability were assessed by using different approaches: (1) direct evaluation of sediment contamination, (2) assessment of bioaccumulation in native benthic invertebrates belonging to different taxonomic/functional groups, and (3) evaluation of the in situ bioavailability of DDT and Hg using passive samplers. Sampling sites were selected upstream and downstream the industrial plant along the river axis. Benthic invertebrates (Gammaridae, Heptageniidae, and Diptera) and sediments were collected in three seasons and analyzed for DDT and Hg content and the results were used to calculate the biota sediment accumulation factor (BSAF). Polyethylene passive samplers (PEs) for DDT and diffusive gradients in thin films (DGTs) for Hg were deployed in sediments to estimate the concentration of the toxicants in pore water. Analysis for (DDx) were performed using GC-MS. Accuracy was within ±30 % of the certified values and precision was >20 % relative standard deviation (RSD). Total mercury concentrations were determined using an automated Hg mercury analyzer. Precision was >5 % and accuracy was within ±10 % of certified values. The results of all the approaches (analysis of sediment, biota, and passive samplers) showed an increasing contamination from upstream to downstream sites. BSAF values revealed the bioavailability of both contaminants in the study sites, with values up to 49 for DDx and up to 3.1 for Hg. No correlation was found between values in sediments and the organisms. Concentrations calculated using passive samplers were correlated with values in benthic invertebrates, while no correlation was found with concentrations in sediments. Thus, direct analysis of toxicant in sediments does not provide a measurement of bioavailability. On the contrary, analysis of bioaccumulation in benthic organisms provides the most realistic picture of the site-specific bioavailability of DDx and Hg, but this approach is time-consuming and not always feasible. On the other hand, the in situ deployment of passive samplers proved to be a powerful tool, providing a good surrogate measure of bioaccumulation.

Tracing endocrine disrupting chemicals in a coastal lagoon (Sacca di Goro, Italy): sediment contamination and bioaccumulation in Manila clams.

The Water Framework Directive, recently amended with new priority substances (2013/39/EU), is meant to regulate the health status of European aquatic environments, including transitional waters. Despite the ecological and economic importance of transitional water bodies and, in particular, of coastal lagoons, a relevant example of this type of environments, little is known about their contamination by priority substances, particularly by endocrine disrupting chemicals (EDCs). In this study, a wide array of priority substances, all with recognised disrupting properties, was investigated in the Sacca di Goro Lagoon (Adriatic Sea, Italy), which receives freshwater from the Po River after draining the most urbanised and industrialised Italian regions. Flame retardants, alkylphenols, bisphenol A, natural and synthetic steroids, personal care products and legacy pollutants were investigated both in sediments and in the clam Ruditapes philippinarum collected from three sites in the lagoon. Sediments showed that most of the chemicals analysed could reach the lagoon ecosystem but their concentrations were below existing quality guidelines. Clams essentially reflected this condition although some concern was raised by polybrominated diphenyl ethers (PBDEs): the limit for the sum of six congeners set for biota in the European Directive (2013/39/EU) to protect human health was exceeded 4-5 times. No significant biota-sediment accumulation factors (BSAFs) were calculated. Nonylphenol, tonalide, PBDE, polychlorinated biphenyls and bisphenol A were the most abundant chemicals in clam tissues.

Exposing native cyprinid (Barbus plebejus) juveniles to river sediments leads to gonadal alterations, genotoxic effects and thyroid disruption.

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.

Concentrations and trophic interactions of novel brominated flame retardants, HBCD, and PBDEs in zooplankton and fish from Lake Maggiore (Northern Italy).

Following the release of the international regulations on PBDEs and HBCD, the aim of this study is to evaluate the concentrations of novel brominated flame retardants (NBFRs), including 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), decabromodiphenyl ethane (DBDPE), hexabromobenzene (HBB), and pentabromoethylbenzene (PBEB), in an Italian subalpine lake located in a populated and industrial area. The study investigated specifically the potential BFR biomagnification in a particular lake's pelagic food web, whose structure and dynamics were evaluated using the Stable Isotope Analysis. The potential BFR biomagnification was investigated by using the trophic-level adjusted BMFs and Trophic Magnification Factors (TMFs), confirming that HBCD and some PBDE congeners are able to biomagnify within food webs. Comparing the calculated values of BMFTL and TMF, a significant positive correlation was observed between the two factors, suggesting that the use of BMFTL to investigate the biomagnification potential of organic chemical compounds might be an appropriate approach when a simple food web is considered.