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The knowledge about the effects of pharmaceuticals on aquatic organisms has been increasing in the last decade. However, due to the variety of compounds presents in the aquatic medium, exposure scenarios and exposed organisms, there are still many gaps in the knowledge on how mixtures of such bioactive compounds affect exposed non target organisms. The crayfish Procambarus clarkii was used to analyze the toxicity effects of mixtures of ciprofloxacin, flumequine and ibuprofen at low and high concentrations (10 and 100 μg/L) over 21 days of exposure and to assess the recovery capacity of the organism after a depuration phase following exposure during additional 7 days in clean water. The crayfish accumulated the three compounds throughout the entire exposure in the hepatopancreas. The exposure to the mixture altered the abundance of proteins associated with different cells functions such as biotransformation and detoxification processes (i.e. catalase and glutathione transferase), carbohydrate metabolism and immune responses. Additionally changes in expression of genes encoding antioxidant enzymes and in activity of the corresponding enzymes (i.e. superoxide dismutase, glutathione peroxidase and glutathione transferase) were reported. Alterations at different levels of biological organization did not run in parallel under all circumstances and can be related to changes in the redox status of the target tissue. No differences were observed between control and exposed organisms for most of selected endpoints after a week of depuration, indicating that exposure to the drug mixture did not produce permanent damage in the hepatopancreas of P. clarkii.

and Purpose Cadmium has been associated with risk of cardiovascular events, including stroke. Human cadmium exposure occurs primarily through diet and tobacco smoke. Recent cohort studies have found an association with stroke, but residual confounding from smoking, could not be ruled out. We therefore conducted a case-cohort study to evaluate whether cadmium is associated with stroke in never-smokers.

The Danish Diet Cancer and Health cohort consists of Danes 50-64 years old, recruited in 1993-1997. From never-smoking cohort members without previous cancer or stroke we sampled a sub-cohort of 1200 persons. We also identified all (n=534) cases in the cohort with a validated stroke diagnosis between baseline and 2009. We quantified cadmium and creatinine concentrations from baseline urine samples and used cadmium per creatinine as our main exposure metric. We used Cox proportional hazards models to estimate hazard ratios (HRs) with age as time scale and adjusting for BMI, education and urinary cotinine withmium exposure among never-smokers are strongly associated with risk of stroke, although results varied somewhat by sex and method of accounting for urinary dilution.A wireless UV-A LEDs lab-scale reactor powered by a resonant inductive coupling (RLC) system was built to maximize the UV photon absorption of agro-industrial wastewaters. The UV-A LEDs (λ = 365 nm) energy was supplied through a magnetic field generated inside of the photoreactor by induction coils placed on the external wall made of polyvinyl chloride. Immersing the light sources in the wastewater increases the photon transfer efficiency and the reaction rate. Maximum magnetic field and optical irradiance were obtained at 26.8 and 27.0 kHz, respectively. As proof-of-concept, elderberry wastewater (EW), olive washing wastewater (OWW) and white and red winery wastewaters (WWW and RWW) were treated combining the wireless UV-A LEDs with the Advanced Oxidation Process (AOP) - Fenton reagent. Ac-PHSCN-NH2 ic50 Fenton experiments were performed using [Fe2+] = 10 mg L-1, [H2O2] = 500 mg L-1, pH = 3 and a reaction time of 4 h. With EW a DOC removal of 35% (k = 0.0696 h-1) was achieved, whereas adding the wireless UV-A LEDs (f = 26.8 kHz) 53% was attained (k = 0.1722 h-1). The Electric Energy per Order (EEO) for the wireless UV-A LEDs consumption was calculated (EEO LEDs = 48.7 kWh m-3 order-1) and for all the remain equipment (air pump, RC box and power amplifier), EEO total = 495 kWh m-3 order-1. Experiments with OWW presented a DOC removal of 62% and a EEO LEDs = 40.5 kWh m-3 order-1; RWW shown 40% of DOC removal and a EEO LEDs = 68.4 kWh m-3 order-1, while with WWW 35% of DOC removal and a EEO LEDs = 79.8 kWh m-3 order-1 were obtained. This work shows that wireless UV-A LEDs can be a promising alternative to conventional UV lamps and wired LEDs in the treatment of real wastewaters. However, optimization of the induction system is still needed, as well as the number and wavelength of the LEDs (e.g. UV-C LEDs) to reduce the overall treatment costs.Anticoagulant rodenticides (AR) resistance has been defined as "a major loss of efficacy due to the presence of a strain of rodent with a heritable and commensurately reduced sensitivity to the anticoagulant". The mechanism that supports this resistance has been identified as based on mutations in the Vkorc1 gene leading to severe resistance in rats and mice. This study evaluates the validity of this definition in the fossorial water vole and explores the possibility of a non-genetic diet-based resistance in a strict herbivorous rodent species. Genetic support was explored by sequencing the Vkorc1 gene and the diet-based resistance was explored by the dosing of vitamins K in liver of voles according to seasons. From a sample of 300 voles, only 2 coding mutations, G71R and S149I, were detected in the Vkorc1 gene in the heterozygous state with low allele frequencies (0.5-1%). These mutations did not modify the sensitivity to AR, suggesting an absence of genetic Vkorc1-based resistance in the water vole. On the contrary, vitamin K1 was shown to be 5 times more abundant in the liver of the water vole compared to rats. This liver concentration was shown to seasonally vary, with a trough in late winter and a peak in late spring/early summer related to the growth profile of grass. This increase in concentration might be responsible for the increased resistance of water voles to AR. This study highlights a non-genetic, diet-related resistance mechanism in rodents to AR. This diet-based resistance might explain the different evolution of the Vkorc1 gene in the fossorial water vole compared to rats and mice.

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