As the global population becomes more concentrated in urban areas, resource consumption, including access to pharmaceuticals, is increasing and chemical use is also increasingly concentrated. Unfortunately, implementation of waste management systems and wastewater treatment infrastructure is not yet meeting these global megatrends. Herein, pharmaceuticals are indicators of an urbanizing water cycle; antidepressants are among the most commonly studied classes of these contaminants of emerging concern. In the present study, we performed a unique global hazard assessment of selective serotonin reuptake inhibitors (SSRIs) in water matrices across geographic regions and for common wastewater treatment technologies. SSRIs in the environment have primarily been reported from Europe (50%) followed by North America (38%) and Asia-Pacific (10%). Minimal to no monitoring data exists for many developing regions of the world, including Africa and South America. From probabilistic environmental exposure distributions, 5th and 95th percentiles for all SSRIs across all geographic regions were 2.31 and 3022.1 ng/L for influent, 5.3 and 841.6 ng/L for effluent, 0.8 and 127.7 ng/L for freshwater, and 0.5 and 22.3 ng/L for coastal and marine systems, respectively. To estimate the potential hazards of SSRIs in the aquatic environment, percent exceedances of therapeutic hazard values of specific SSRIs, without recommended safety factors, were identified within and among geographic regions. For influent sewage and wastewater effluents, sertraline exceedances were observed 49% and 29% of the time, respectively, demonstrating the need to better understand emerging water quality hazards of SSRIs in urban freshwater and coastal ecosystems. This unique global review and analysis identified regions where more monitoring is necessary, and compounds requiring toxicological attention, particularly with increasing aquatic reports of behavioral perturbations elicited by SSRIs.

Di-isononyl phthalate (DINP) is used as a substitute for traditional phthalates, in a wide range of applications. However, there is growing concern regarding its toxicity. Studies have indicated that DINP is related to thyroid hormone disorder and that phthalates can affect thyroid normal function. In this study, we aim to determine any effects of DINP exposure on autoimmune thyroid disease (AITD), the most common autoimmune disease, and to understand the underlying causal mechanism. AITD model Wistar rats were exposed to 0.15 mg/kg, 1.5 mg/kg or 15 mg/kg DINP. We assessed the thyroid globulin antibody levels, Th1/Th2 balance, histopathological changes and caspase-3 levels in the thyroid. The data show that exposure to DINP does indeed aggravate AITD. To explore the underlying mechanisms, we examined the levels of microtubule-associated protein 1 light chain 3 B (LC3B), Sequestosome 1 (SQSTM1) and the appearance of autophagosomes or autolysosomes to assess autophagy in the thyroid. The results show that DINP can suppress normal autophagy. We found that DINP induced an exacerbation of oxidative stress and the activation of the Akt/mTOR pathway, indicating that oxidative stress and activation of mTOR may play a key role in these processes. Moreover, the activation of mTOR also promoted the expression of IL-17. Importantly, blocking oxidative stress with VE or blocking Akt/mTOR with rapamycin mitigated the exacerbation of AITD and the suppression of normal autophagy. All these results indicate that exposure to DINP, especially high doses of DINP, can aggravate oxidative stress and activate the Akt/mTOR pathway. This exposure then leads to a suppression of normal autophagy and expression of IL-17 in the thyroid, resulting in an eventual exacerbation of AITD.

The present study deals with the cyto-genotoxicological impact of ionic liquids, 1-butyl-3-methylimidazolium bromide, trihexyl tetradecylphosphonium dicyanamide, 1-decyl-3-methylimidazolium tetrafluoroborate, benzyldimethyltetradecylammonium chloride, and 1-butyl-4-methylpyridinium chloride, on animal cells and their biodegradation. The long alkyl chain containing ionic liquids were found to be more toxic whereas benzene functional group in benzyldimethyltetradecylammonium chloride enhances its toxicity. Aerobic bacterial granules, a bacterial consortium, were developed that have promising ability to break down these organic pollutants. These aerobic bacterial granules have been applied for the biodegradation of ionic liquids. The biological oxygen demand (5 days) and chemical oxygen demand parameters confirmed that the biodegradation was solely due to aerobic bacterial granules which further decreased the time period needed for regular biodegradation by biological oxygen demand (28 days). The high resolution mass spectrometry analysis further approved that the degradation of ionic liquids was mainly via removal of the methyl group. Elevated N-demethylase enzyme activity supports the ionic liquids degradation which may be occurring through demethylation mechanism. The amplicon sequencing of aerobic bacterial granules gives insight into the involvement of the bacterial community in the biodegradation process.

Per- and poly-fluoroalkyl substances (PFAS) have attracted considerable concern due to their widespread occurrence in the environment and potential human health risks. Given the complexity of PFAS retention in multi-phase systems, it would be useful for characterization and modeling purposes to be able to readily determine the relative significance of the individual retention processes for a given PFAS and set of subsurface conditions. A quantitative-structure/property-relationship (QSPR) analysis was conducted for adsorption of PFAS by soils, sediments, and granular activated carbon (GAC), and integrated with a prior analysis conducted for adsorption to air-water and oil-water interfaces. The results demonstrated that a model employing molar volume provided reasonable predictions of organic-carbon normalized soil/sediment adsorption coefficients (log Kₒc), GAC-adsorption coefficients (log Kd), and air/oil-water interfacial adsorption coefficients (log Kᵢ) for PFAS. The relative magnitudes of solid-water and air/oil-water interfacial adsorption were compared as a function of controlling variables. A nomograph was developed that provides a first-order determination of the relative significance of these interfacial adsorption processes in multi-phase porous-media systems.

Azoles are effective antifungal agents used in both medicine and agriculture. They typically work by inhibiting cytochrome P450 enzymes, primarily CYP51 of the ergosterol biosynthesis pathway, thus damaging the fungal cell membrane. However, apart from their desired antifungal properties, several azoles also exhibit endocrine disrupting properties in mammals, both in vitro and in vivo. Here, we have tested two currently used agricultural azole fungicides, triticonazole and flusilazole, for their in vitro anti-androgenic activity and potential effects on reproductive parameters. Both fungicides showed strong androgen receptor (AR) antagonism and disruption of steroid biosynthesis in vitro. Following gestational exposure to flusilazole (15 or 45 mg/kg bw/day) or triticonazole (150 or 450 mg/kg bw/day) in time-mated Sprague Dawley rats, triticonazole induced shorter male anogenital distance (AGD). Flusilazole exposure did not affect the AGD, but altered fetal male blood hormone profile, with increased androstenedione and decreased estrone levels. Flusilazole and triticonazole have dissimilar effects on reproductive parameters in vivo, but both show endocrine disrupting activities.

Plastic debris has been recognized as a growing threat to marine biota due to its widespread distribution and possible interactions with marine species. Concerns over the effects of plastic polymers in marine ecosystems is reflected in the high number of toxicological studies, regarding microplastics (<5 mm) and marine fauna. Although several studies reported that organisms ingest and subsequently eliminate microplastics (MP), the potential effects at organ and tissue level remain unclear, especially considering exposure to different microplastic sizes and concentrations. The present study aimed at investigating potential pathophysiological effects of the ingestion of MP by marine filter-feeders. For the purpose, Mediterranean mussel (Mytilus galloprovincialis) was exposed to spherical polystyrene MP (2 and 10 μm Ø) over short- and medium-term exposure periods, under single and combined concentrations that represent high, yet realistic doses (10 and 1000 MP mL−1). Overall, results suggest rapid MP’ clearance from water column by filtering, regardless of MP size. Ingestion occurred, identified by MP in the lumen of the gut (mostly in midgut region), followed by excretion through faeces. However, no MP were found in gills or digestive gland diverticula. Biochemical indicators for oxidative stress were generally irresponsive regardless of organ and time of exposure. Small foci of haemocytic infiltration in gastric epithelia were found, albeit not clearly related to MP ingestion. Globally, no evident histopathological damage was recorded in whole-body sections of exposed animals. The present findings highlight the adaptative ability of filter-feeding bivalves to cope with filtration of suspended MP, resulting in rapid elimination and reduced internal damage following ingestion of spherical MP. Nevertheless, the fact that the animals are able to translocate MP to the gut reveals that filter feeding organisms may indeed became a target of concern for fragmented materials with smaller, mixed sizes and sharper edges.

The increasing production and use of graphene-based nanomaterials (e.g., graphene oxide (GO) and reduced graphene oxide (RGO)) will lead to their environmental release. To date, transport of RGOs in saturated porous media is poorly understood. Here, we examined the transport behaviors of three RGO materials obtained by reducing a GO product with commonly used reducing agents – N₂H₄, NaBH₄ and L-ascorbic acid (referred to as N₂H₄-RGO, NaBH₄-RGO and VC-RGO, respectively). When the dominant background cation was Na⁺, K⁺ or Mg²⁺, the mobility of the RGOs and GO in saturated quartz sand correlated well with their surface C/O ratio. Interestingly, the lower mobility of the more reduced materials (the ones with higher C/O values) was not only the results of their less negative surface charges and larger particle sizes, but also the outcome of their greater hydrophobicity, in line with the calculated extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) profiles. Counterintuitively, when the background cation was Ca²⁺, the least reduced material among the three RGOs, VC-RGO, exhibited the lowest mobility. Analysis of electrophoretic and aggregation properties, as well as pH-effect experiments, indicated that the surprisingly low mobility of VC-RGO was attributable to the strong cation-bridging effect (primarily Ca²⁺-bridging between RGO and quartz sand) associated with this material, as VC-RGO contained the highest amount of surface carboxyl group (a strong metal-binding moiety). Notably, enhanced attachment (due to increased hydrophobic effect and cation-bridging) and particle aggregation appeared to work synergistically to increase RGO retention, as the attachment of large RGO aggregates significantly enhanced particle straining by narrowing the flow path. These observations reveal a largely overlooked link between the mobility of graphene-based materials and their key physicochemical properties.

Particulate matter (PM) oxidative potential (OP) is an emerging health metric, but studies examining the OP of indoor PM are rare. This paper focuses on the relationships between respiratory exposure to OP and PM water-soluble composition in indoor environments. Size-resolved PM samples were collected between November 2015 and June 2016 from an office, home (including bedroom, living room, and storeroom), and laboratory using a MOUDI sampler. Particles from each source were segregated into eleven size bins, and the water-soluble metal content and dithiothreitol (DTT) loss rate were measured in each PM extract. The water-soluble OP (OPwₛ) of indoor PM was highest in the office and lowest in the home, varying by factors of up to 1.2; these variations were attributed to differences in occupation density, occupant activity, and ventilation. In addition, the particulate Cu, Mn, and Fe concentrations were closely correlated with OPwₛ in indoor particles; the transition metals may have acted as catalysts during oxidation processes, inducing ·OH formation through the concomitant consumption of DTT. The OPwₛ particle size distributions featured single modes with peaks between 0.18 and 3.2 μm across all indoor sites, reflecting the dominant contribution of PM₃.₂ to total PM levels and the enhanced oxidative activity of the PM₃.₂ compared to PM>₃.₂. Lung-deposition model calculations indicated that PM₃.₂ dominated the pulmonary deposition of the OPwₛ (>75%) due to both the high levels of metals content and the high deposition efficiency in the alveolar region. Therefore, because OPwₛ has been directly linked to various health effects, special attention should be given to PM₃.₂.

Plastic pollution is widespread in all the oceans and seas, representing a significant threat to most of their ecosystems even in marine protected areas (MPAs). This study determines the floating plastic distribution in four different periods between 2014 and 2015 in the recently approved Menorca Channel MPA (Balearic Islands). Plastic debris were persistent during all sampling periods on the surface of the Channel, composed mainly by the microplastic sizes. Average particle abundances ranged from 138,293 items⋅km−2 in autumn to 347,793 items⋅km−2 during the spring, while weight densities varied from 458.15 g(DW)⋅km−2 in winter to 2016.67 g(DW)⋅km−2 in summer. Rigid plastics were the most frequent particles in all the periods analysed (from 89.40%-winter to 94.54%-spring). The high-resolution and particle distribution models corroborated that the oceanographic variability shapes different patterns of presence of plastics, and in particular the existence of areas with almost no plastics.

Understanding the chemical response and characteristics of bacterial communities in soil is critical to evaluate the effects of selenium (Se) supplement on plant growth and chromium (Cr)/Se uptake in Cr contaminated soil. The rhizosphere soil characteristics of pak choi (Brassica campestris L. ssp. Chinensis Makino) were investigated in soil contaminated with different levels and forms of Cr when supplemented with Se. Although inhibition of plant growth caused by Cr stress was not completely alleviated by Se, Cr content in plant tissues decreased in Cr(VI)120Se5 treatment (Cr(VI): 120 mg kg−1 soil; Se: 5 mg kg−1 soil) and its bioavailability in soil decreased in Cr(III)200Se5 (Cr(III): 200 mg kg−1 soil; Se: 5 mg kg−1 soil) treatment. Moreover, antagonism of Cr and Se on soil enzyme activities and bacterial communities were revealed. Notably, results of Cr(VI) reduction and Se metabolism functional profiles confirmed that bacterial communities play a critical role in regulating Cr/Se bioavailability. Additionally, the increases of Se bioavailability in Cr contaminated soil were ascribed to oxidation of Cr(VI) and reduction of Se reductases proportions, as well as the enhancing of pH in soil. These findings reveal that Se has the potential capacity to sustain the stability of microdomain in Cr contaminated soil.