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One of the primary sources of trace elements in the environment is wastewater used for irrigation. However, the effects of untreated wastewater containing high concentrations of chromium and zinc on vegetables and the potential human health risks associated with their consumption are poorly understood. This pot experiment aimed to address this research gap. The accumulation of chromium and zinc and their effect on the biochemical parameters of lettuce (Lactuca sativa) and green onion (Allium fistulosum L.) irrigated with untreated industrial effluents were assessed. The average concentrations of chromium and zinc in the edible parts of the vegetables ranged between 7.36 and 7.58 mg/kg dry weight and 59.8 and 833 mg/kg dry weight, respectively. The irrigation of the lettuce with the effluent containing zinc at a concentration of 2.95 mg/L led to a significant increase in the content of phenols and the antioxidant activity. A significant reduction in the chlorophyll content of the lettuce leaves and the antioxidant activity of the onion leaves was observed when the plants were irrigated with the effluent containing zinc at a concentration of 78 mg/L. No non-carcinogenic health risk from the intake of chromium and zinc was identified through the consumption of lettuce and green onion, primarily due to the fact that a smaller proportion of the total metal content was transferred to their edible parts. [ABSTRACT FROM AUTHOR]

The extensive development of nanotechnologies has allowed nanoparticles to impact living systems through different pathways. The effect of single exposure to high concentrations of silver and copper nanoparticles (50–200 mg/L) on Vaccinium myrtillus L. under field conditions was investigated. Nanoparticle uptake in different segments of Vaccinium myrtillus L. was assessed by applying inductively coupled plasma–atomic emission spectroscopy and a particle-induced X-ray emission technique. Copper nanoparticles mainly accumulated in the roots and leaves, while silver nanoparticles showed a higher affinity for the roots and berries. The nanoparticles' effects on the pigments and antioxidant activity of the plant's leaves were also evaluated. The possible human health risk associated with the consumption of nanoparticle-contaminated berries was assessed. The results indicated that the consumption of berries contaminated with nanoparticles presented a low risk for human health. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study investigates the biocompatibility and physiological impacts of silver nanoparticles (AgNPs) functionalized with Spirulina protein extract (SPE) on laboratory rats. The objective was to assess and compare the systemic distribution, organ accumulation, and changes in hematological and biochemical parameters between biofunctionalized and non-functionalized silver nanoparticles. Methods: AgNPs were functionalized with SPE. Adult Wistar rats were administered these nanoparticles to assess their distribution across various organs using ICP-MS analysis. Hematological and biochemical markers were measured to evaluate systemic effects. Results: Functionalized silver nanoparticles demonstrated preferential accumulation in the brain, liver, and testicles, with significant clearance observed post-administration. The persistence of AgNPs SPE in reproductive organs was established. Hematological analysis revealed moderate changes, suggesting mild immune activation. Biochemical tests indicated transient increases in liver enzymes, signaling reversible hepatic stress. Conclusions: The biofunctionalization of AgNPs with Spirulina protein extract modifies the nanoparticles' systemic behavior and organ distribution, enhancing their biocompatibility while inducing minimal physiological stress. These findings support the potential of Spirulina-based coatings to mitigate the toxicity and enhance the therapeutic efficacy of nanomedical agents. [ABSTRACT FROM AUTHOR]

Nanoparticles, due to their extensive production and application, can have significant consequences for the environment, including soil and plant pollution. Therefore, it is very important to assess how nanoparticles will affect plants depending on the exposure pathways. The effect of gold nanoparticles in a concentration range of 1–100 mg/L on Mentha spicata L. during a 28-day experiment was investigated. Two routes of nanoparticles exposure were applied: root and foliar. Transmission electron microscopy was used to characterize nanoparticles and their effect on plant leaves' ultrastructure. Gold content in soil and plant segments was determined using k0-neutron activation analysis. For root exposure, gold was mainly accumulated in soil (15.2–1769 mg/kg) followed by root systems (2.99–454 mg/kg). The maximum accumulation of gold in leaves (5.49 mg/kg) was attained at a nanoparticle concentration of 100 mg/L. Foliar exposure resulted in the maximum uptake of gold in leaves (552 mg/kg) and stems (18.4 mg/kg) at the highest applied nanoparticle concentration. The effect of nanoparticles on the Mentha spicata L. leaves' biochemical composition was assessed. Nanoparticles affected the content of chlorophyll and carotenoids and led to an increase in antioxidant activity. Root exposure to gold nanoparticles resulted in an increase in the number of starch grains in chloroplasts and also suppressed the activity of the soil microbiota. Gold extraction from mint leaves into herbal infusion varied from 2 to 90% depending on the concentration of nanoparticles in the solution and the exposure route. The health risk as a result of gold exposure via herbal tea intake was assessed through estimated daily intake. The hazard quotient values were found to be less than the cutoff, indicating that a cup of tea infusion should not cause a serious impact to human health. [ABSTRACT FROM AUTHOR]

Praseodymium, the sixth-most abundant rare-earth element, is widely used in the aircraft industry for the elaboration of refractory substances, coloring materials, lighting equipment, and fiber optical cables. Living and non-living Arthrospira platensis biomass was applied for Pr(III) removal from aqueous solutions. In bioaccumulation experiments, the effect of Pr(III), introduced into the medium in a concentration range of 10–30 mg/L, on biomass productivity, biochemical composition, and antioxidant activity was assessed. The biomass showed high accumulation capacity (more than 99%) toward Pr(III). Supplementation of the cultivation medium with Pr(III) led to a decrease in carbohydrate and lipid content, but it did not significantly influence biomass productivity or the content of proteins and pigments. In experiments with non-living biomass, the effect of pH, Pr(III) concentration, temperature, and contact time on the efficiency of metal removal was investigated. The maximum uptake of Pr(III) was achieved at pH 3.0 after 3.0 min of interaction. The equilibrium data were explained using the Langmuir and Freundlich models, while the kinetics of the process was described by applying pseudo-first-order, pseudo-second-order, and Elovich models. The maximum sorption capacity of Arthrospira platensis biomass calculated from the Langmuir model was 99.3 mg/g. According to the thermodynamic calculations, the process of Pr(III) removal was spontaneous and exothermic in nature. The obtained data can be used for the development of environmentally-friendly technology for Pr(III) recovery from wastewater as well as to understand the effect of Pr(III) on aquatic organisms. [ABSTRACT FROM AUTHOR]

The study aimed to assess the effect of some Co(II) compounds on the production of biomass, β-carotene and astaxanthin by green microalga Haematococcus pluvialis at different stages of its life cycle. Cobalt compounds (Co(OAc)2 and CoCl2) were added to the nutrient medium of Haematococcus pluvialis on the first day of the cultivation cycle. The biomass of H. pluvialis was collected according to some conventional stages of the life cycle: day 3 - green cell stage; day 10 - brown cell stage, and day 14 - aplanospore stage. Changes in the amount of microalgae biomass were determined depending on the stage of the life cycle, as well as the content of β-carotene and astaxanthin pigments. Analysis of the data obtained in the course of a series of experiments indicates that the studied Co(II) compounds did not inhibit cell proliferation within the limits of applied concentrations. Co(II) acetate, depending on the concentration, was involved in the processes of cell multiplication and the synthesis of ß-carotene. In concentrations of 1.5 and 2.0 mg/L, Co(OAc)2 stimulated biomass and astaxanthin production. CoCl2 was involved in the proliferation of microalgae cells, the green cell stage being the most sensitive to the action of the compound. [ABSTRACT FROM AUTHOR]

Europium recovery from wastewater is determined by its high significance for industry and toxicity for living organisms. The capacity of cyanobacteria Arthospira platensis (Spirulina) to remove Eu(III) through biosorption and bioaccumulation was evaluated. In biosorption experiments, the effects of four variables pH, metal concentration, time, and temperature on metal removal were studied. In bioaccumulation experiments, the effect of Eu(III) concentrations on biomass bioaccumulation capacity and biochemical composition was assessed. The efficiency of Eu(III) uptake in both experiments was determined using ICP-AES techniques. Maximum biosorption of Eu(III) was achieved at pH 3.0. Equilibrium data fitted well with the Langmuir and Freundlich models, with maximum adsorption capacity of 89.5 mg/g. The pseudo-first-, pseudo-second-order, and Elovich models were found to correlate well with the experimental data. According to thermodynamic studies the sorption was feasible, spontaneous, and endothermic in nature. At addition of Eu(III) ions in the cultivation medium in concentrations of 10–30 mg/L, its accumulation in biomass was 9.8–29.8 mg/g (removal efficiency constituting 98–99%). Eu(III) did not affect productivity and content of carbohydrates and pigments in biomass but led to the decrease of the content of protein and an increase in the amount of MDA. The high Eu(III) biosorption and bioaccumulation efficiency of Arthrospira platensis may constitute an effective and eco-friendly strategy to recover it from contaminated environment. [ABSTRACT FROM AUTHOR]