This work present aims to evaluate the effect of a conventional wastewater treatment process on the number of nanoparticles, and the role of nanoparticles as a carrier of antibiotics. A set of methods based on asymmetrical flow field flow fractionation coupled with multi-angle light scattering to separate and quantify nanoparticles in real wastewater was established. The characterization of nanoparticles was conducted by transmission electron microscopy, energy dispersive spectrometer, UV–visible spectrophotometer and three-dimensional excitation-emission matrix fluorescence spectroscopy. The adsorption of different sizes of nanoparticles separated from the real wastewater for four targeted antibiotics (sulfadiazine, ofloxacin, tylosin and tetracycline) was studied. The results show that the number of nanoparticles were increased in the wastewater treatment process and the size range between 60 and 80 nm was predominant in wastewater samples. The nanoparticles were mainly composed of O, Si, Al and Ca elements and organic components were in the size range of 0–10 nm. Targeted antibiotics were dominantly adsorbed onto nanoparticles with 60–80 nm size range at each stage. The concentrations of tetracycline adsorbed on nanoparticles were surprisingly increased in the end of the treatment process, while ofloxacin and tylosin had the completely opposite phenomenon to tetracycline. The pH and ionic strength definitely affected the aggregation of nanoparticles and interaction with the antibiotics. It is of great significance to give insights into nanoparticle-antibiotic assemblages for the effective treatment and avoiding the water risks due to nanoparticles’ ubiquitous and their risks of carrying antibiotics.

Environmental contamination is one of the major factors or cofactors affecting amphibian populations. Since 2000, the number of studies conducted in laboratory conditions to understand impacts of chemical exposures increased. They aimed to characterize biological effects on amphibians. This review proposes an overview of biological responses reported after exposures to metals, phytopharmaceuticals or emerging organic contaminants and focuses on endpoints relating to reproduction and development. Due to amphibian peculiar features, these periods of their life cycle are especially critical to pollutant exposures.Despite the large range of tested compounds, the same model species are often used as biological models and morphological alterations are the most studied observations. From the results, the laboratory-to-field extrapolation remained uneasy and exposure designs have to be more elaborated to be closer to environmental conditions. Few studies proposed such experimental approaches. Lastly, gametes, embryos and larvae constitute key stages of amphibian life cycle that can be harmed by exposures to freshwater pollutants. Specific efforts have to be intensified on the earliest stages and notably germ cells.

Heavy metal cadmium (Cd) is a widespread environmental contaminant with a potential toxicity that might adversely influence the health of experimental animals and humans. It has been known that Cd might accumulate in vertebrates for many years and thus leads to the hepatic and renal toxicity. Additionally, Cd concentration in the ovary increases with age and is highly related to the reproductive hazard. However, the underlying mechanisms regarding how Cd affects the female reproductive system especially the oocyte quality have not yet fully defined. Here, we reported that Cd exposure led to the defective nuclear maturation of oocytes via the impairment of cytoskeleton assembly, displaying the aberrant spindle organization, chromosome alignment and actin polymerization. In the meantime, Cd exposure caused the impaired cytoplasmic maturation by showing the disrupted dynamics of mitochondrial integrity and cortical granules, and thereby resulting in the compromised sperm binding ability and fertilization capacity of oocytes. More importantly, we found that glutathione (GSH) supplementation was able to recover the meiotic failure induced by Cd exposure through suppressing the excessive ROS level, DNA damage accumulation and apoptotic incidence. Taken together, our findings demonstrate that Cd exposure has the adverse effects on the oocyte meiotic maturation as well as subsequent fertilization, and provide a potential effective strategy to improve the quality of Cd-exposed oocytes.

Mytilus galloprovincialis was exposed to seawater spiked with 5, 50 and 100 μg L⁻¹ of Titanium (Ti) for 14 days. Seawater was renewed after 96 h and new addition of Ti was done. A parallel experiment conducted in the absence of mussels showed that during the first 24 h after spiking, Ti concentrations in seawater rapidly decreased to values below 2 μg L⁻¹. For this reason, along the entire experimental period (14 days) mussels were exposed to Ti during two short periods, in the beginning of the experiment and after seawater renewal. At 96 h, mussels exhibited low Ti concentrations (<2.5 μg g⁻¹), close or not significantly different from a control condition (1.6 μg g⁻¹ in the absence of Ti). Despite the low accumulated Ti in mussels’ tissues after both experimental periods (96 h and 14 days), biochemical markers indicated that mussels developed two main strategies: reduction of their metabolic capacity to avoid the uptake of Ti, and antioxidant and biotransformation defense mechanisms, such as the activation of SOD, CAT, GPx and GSTs enzymes that were triggered to prevent cellular damages. Nevertheless, oxidative stress occurred after 96 h or 14 days. The current study highlights that alterations of biological activity of M. galloprovincialis exposed to Ti goes beyond its accumulation in tissues.

In this study, data collected from an urban air quality monitoring network are being used for the purpose of evaluating various methodologies used for spatial interpolation in the context of proposing an effective yet simple to apply scheme for PM spatial point estimations. The examined methods are the Inverse Distance Weighting, two linear regression models, the Multiple Linear Regression and the Linear Mixed Model, along with a Feed Forward Neural Network (FFNN) model. These schemes utilize daily PM₁₀ and PM₂.₅ concentrations collected from five and three air quality monitoring sites respectively. In order to obtain the resulted estimations, the leave-one-out cross-validation methodology is used for all methods. The evaluation of their predictive ability is performed by using a combination of difference and correlation statistical measures, scatter plots and statistical tests. The results indicate the usefulness of FFNNs as they are found to be statistically significantly superior for modelling the particulate matter spatial variability. The model performance statistics show that in most cases the error values are considerably lower for the FFNN model. Additionally, the rank and Wilcoxon rank tests reveal that the null hypothesis for equal predictive accuracy is rejected for the majority of monitoring sites and schemes (values lower than the critical t-value). According to the comparison results, the FFNN model is selected for forecasting air quality limit exceedances set by the European Union and World Health Organization air quality standards. For two monitoring sites in which the largest number of exceedances occurred, the probability of detection is high while the probability of false detection is very low, further establishing the neural networks’ predictive ability.

Biodegradation assays involve both biodegradation and analytical processes which can be affected by systematic errors, among others. These errors can affect all the environmentally relevant parameters related to biodegradability, enantioselectivity (in the case of chiral compounds), kinetic parameters and persistence of chemicals. However, such impacts have never been well-characterized. In this work, calculations and models used for a long time are studied by simulating systematic errors at the 5% level, which affect independently the analytical calibration step and the biodegradation process. The impact of these errors is also compared with those obtained from an alternative approach: recently proposed equations and a novel model (a Monod modified version) developed in this work. All simulations are compatible with an environmentally relevant pollutant concentration. The results suggest a high degree of minimization (or even cancelation) of the systematic error impact using the alternative approach respect to the conventional one. These findings can be interpreted either in view of achiral or chiral pollutants. The present work can have a positive impact in the area of risk assessment of new pollutants and hazardous materials.

This study was conducted to investigate mycotoxin exposure in 260 rural residents (age 18–66 years) in Nanjing, China. Paired plasma and first morning urine samples were analyzed for 26 mycotoxin biomarkers, including 12 parent mycotoxins and 14 mycotoxin metabolites, by an ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method. Mycotoxins and their metabolites were detected in 95/260 (36.5%) plasma samples and 144/260 (55.4%) urine samples. The most prevalent mycotoxin in plasma was ochratoxin A (OTA), with the incidence of 27.7% (range 0.312–9.18 μg/L), while aflatoxin B₁-lysine (AFB₁-lysine) (incidence 19.6%, range 10.5–74.5 pg/mg albumin), fumonisin B₁ (FB₁) (incidence 2.7%, range 0.305–0.993 μg/L), deoxynivalenol (DON) (incidence 2.3%, range 1.39–5.53 μg/L), zearalenone (ZEN) (incidence 6.5%, range 0.063–0.418 μg/L) and zearalanone (ZAN) (incidence 1.2%, range 0.164–0.346 μg/L) were also detected in plasma samples. Deoxynivalenol-15-glucuronide (DON-15-GlcA) was the most frequently detected urinary mycotoxin, with the incidence of 43.8% (range 0.828–37.7 μg/L). DON (incidence 10.0%, range 1.39–14.7 μg/L), DON-3-glucuronide (DON-3-GlcA) (incidence 15.8%, range 0.583–5.84 μg/L), aflatoxin M₁ (AFM₁) (incidence 10.4%, range 0.125–0.464 μg/L), ZAN (incidence 7.7%, range 0.106–1.82 μg/L), ZEN (incidence 6.9%, range 0.056–0.311 μg/L), FB₁ (incidence 3.1%, range 0.230–1.33 μg/L), T-2 toxin (incidence 2.3%, range 0.248–3.61 μg/L) and OTA (incidence 1.2%, range 0.153–0.557 μg/L) were also found in urine samples. Based on the plasma or urinary levels, the daily intakes of AFB₁, FB₁, ZEN, DON and OTA were estimated. The results showed that the investigated rural dwellers were exposed to multiple mycotoxins, especially to carcinogenic mycotoxin AFB₁ with a mean daily intake of 0.41 μg/kg·bw/day, thereby underlining a potential public health concern. To the best of our knowledge, this is the first study to evaluate human exposure to mycotoxins with direct measurements of multiple mycotoxins in paired plasma and urine samples for over 200 subjects of a single population.

The present endocrine disrupting chemicals (EDCs) in wastewater effluents due to incomplete removal during the treatment processes may cause potential ecological and human health risks. This study evaluated the removal and uptake of seven EDCs spiked in two types of wastewater effluent (i.e., ultrafiltration and ozonation) and effluent cultivated with the freshwater green alga Nannochloris sp. In ultrafiltration effluent cultivated with Nannochloris sp. for 7 days, the removal rate of 17β-estradiol (E2), 17α-ethinylestradiol (EE2), and salicylic acid (SAL) was 60%; but Nannochloris sp. did not promote the removal of other EDCs studied. The algal-mediated removal of E2, EE2, and SAL was attributed to photodegradation and biodegradation. Triclosan (TCS) underwent rapid photodegradation regardless of adding algae in the effluent with 63%–100% removal within 7 days. Triclosan was also found associated with algal cells immediately after adding algae, and thus the primary mechanisms involved were photodegradation and bioremoval (i.e., bioadsorption and bioaccumulation). After algal cultivation, TCS still has a bioaccumulation potential to pose high risks within the food web and the endocrine disrupting properties of the residual estrogens in the effluent are not eliminated. Algal cultivation can be exploited to treat wastewater effluents but the removal efficiencies of EDCs highly depend on chemical types.

Five types of crop residue (rice, wheat, corn, sorghum, and sugarcane) collected from different provinces in China were used to characterize the chemical components and bioreactivity properties of fine particulate matter (PM2.5) emissions during open-burning scenarios. Organic carbon (OC) and elemental carbon (EC) were the most abundant components, contributing 41.7%–54.9% of PM2.5 emissions. The OC/EC ratio ranged from 8.8 to 31.2, indicating that organic matter was the dominant component of emissions. Potassium and chloride were the most abundant components in the portion of PM2.5 composed of water-soluble ions. The coefficient of divergence ranged from 0.27 to 0.51 among various emissions profiles. All samples exposed to a high PM2.5 concentration (150 μg/mL) exhibited a significant reduction in cell viability (A549 lung alveolar epithelial cells) and increase in lactic dehydrogenase (LDH) and interleukin 6 levels compared with those exposed to 20 or 0 μg/mL. Higher bioreactivity (determined according to LDH and interleukin 6 level) was observed for the rice, wheat, and corn samples than for the sorghum straw samples. Pearson's correlation analysis suggested that OC, heavy metals (chromium, manganese, iron, nickel, copper, zinc, tin, and barium), and water-soluble ions (fluoride, calcium, and sulfate) are the components potentially associated with LDH production.

A scientific campaign was undertaken along the Western sector of the Mediterranean Sea in the summer 2015 (26th Jun to 13th Jul), with the goal of gathering information about organic contaminants affecting marine aerosol over the Italian seas and with a special focus on changes in composition due to sources. 24 PM₁₀ atmospheric samples in total were chemically characterized, including polycyclic aromatic hydrocarbons (PAHs), aliphatic hydrocarbons (n-alkanes) and phthalate esters. Contemporarily, regulated gaseous toxicants (i.e. ozone, nitrogen oxides and sulfur dioxide) and meteorological parameters were recorded. Samplings were carried out inshore in front of harbors (N = 7) and along the cruise, both during the vessel shipping (N = 11, transects) and at its stops offshore (N = 6). Total PAH concentrations ranged from 0.03 to 1.94 ng/m³ and raised close to harbors and coastal sites, confirming that continental sources were responsible for the strong increase of pollution levels there compared to offshore. The percent composition and diagnostic ratio rates of PAHs were different for harbors, while transects were in agreement with offshore stops, possibly due to the different impact of pollution sources. n-Alkanes (C₂₁C₃₈) and the corresponding carbon preference index rates (CPI) were assessed; their values ranged 8.7–90 ng/m³ and 1.1–2.9 respectively, which suggested that fossil fuel combustion was the dominant source, though biogenic emission could contribute. Alkyl phthalates revealed wide variability in concentrations among aerosol samples. Moreover, long-range atmospheric transport and particle ageing effect induced by photo-oxidants were important factors controlling the composition of organic aerosols in the Mediterranean Sea air.