The study aimed to assess the genotoxic potential of silica-coated iron oxide nanoparticle functionalized with dithiocarbamate groups (IONP, 100 nm) in vitro exposure alone or its interference with mercury (Hg) co-exposure in the blood of European eel (Anguilla anguilla L.) by evaluating 8-hydroxy-2′-deoxyguanosine (8-OHdG), lipid peroxidation (LPO), and erythrocytic nuclear abnormalities (ENA). Four groups were made: (i) 2 × 10⁶erythrocytes + Roswell Park Memorial Institute-1640 (RPMI-1640) (control), (ii) 2 × 10⁶erythrocytes + IONP (2.5 mg L⁻¹), (iii) 2 × 10⁶erythrocytes + Hg (50 μg L⁻¹), and (iv) 2 × 10⁶erythrocytes + IONP + Hg. Blood plasma was also processed following the previous exposure conditions. Samplings were performed at 0, 2, 4, 8, 16, 24, 48, and 72 h of exposure. The results revealed significant ENA increases at both early (2, 4, 8) and late (16, 24, 48, 72) hours of exposure to IONP alone. However, IONP exposure combined with Hg co-exposure revealed no ENA increase at 2 h, suggesting that IONP-Hg complex formation is efficient to eliminate the DNA damage induced by individual exposure to IONP or Hg at early hours. Hence, the initial occurrence of antagonism between IONP and Hg was perceptible; however, at late hours of exposure, IONP was unable to mitigate the mercury-accrued negative impacts. Plasma exposure to IONP alone displayed a significant increase in 8-OHdG levels at 2 and 48 h of exposure. However, IONP in combination with Hg co-exposure revealed an increase in 8-OHdG levels at all the exposure length (except 16 h), suggesting that both IONP and Hg independently oxidized DNA. In addition, an additive effect on 8-OHdG levels at both early and late hours, and on LPO only at late hours (except 24 h), suggested that DNA is more susceptible to peroxidative damage than lipid.

The availability of rapid and effective methodologies for assessing lotic systems with microphytobenthos is still quite scarce. Hence, the primary goal of this study was to optimize the growth conditions of the sensitive and ubiquous benthic diatom Navicula libonensis for laboratorial and field assessments. The effect of different conditions of temperature, photoperiod, initial cell density, test duration and cell encapsulation into calcium alginate beads was evaluated in a first set of experiments. There was a slight increase in the growth of free and immobilized cells at 23 °C, at lower initial cell densities and at the shortest experimental period (6 days). Through all the conditions, the growth profiles of free versus immobilized were fairly variable. A second experimental trial involved the validation of selected conditions, applied to the ecotoxicological testing of N. libonensis to two reference chemicals—3,5-dichlorophenol and potassium dichromate. A similar response of free and immobilized cells was observed between exposures to spiked stream water and synthetic medium, and through the conditions tested. This outcome suggests that N. libonensis may potentially provide reliable responses under direct in situ exposures.

Aiming to evaluate responses in terms of growth rates, physiological parameters, and degree of sensitivity to SO₂ and SPMFₑ in Eugenia uniflora L. (Myrtaceae, a C₃ species) and Clusia hilariana Schlecht (Clusiaceae, a CAM species); saplings were exposed to emissions from a pelletizing factory for 7 months. The species were distributed along a transect (200, 500, 800, 1400, and 1700 m away from the emission source), and analyses were performed after 71, 118, and 211 days of exposure to the pollutants. E. uniflora received higher superficial deposition of particulate iron. The highest total iron foliar contents were observed 200 m away from the emission source in both plant species, while the highest total sulfur foliar contents were observed 200 m away in C. hilariana and 800 m away in E. uniflora. E. uniflora presented decreased values of height growth rate, number of necrotic leaves, chlorophyll analysis (SPAD index) and transpiration, in relation to the distances from the emission source. C. hilariana showed decreased values of height growth rate, number of leaves, number of necrotic leaves, total ionic permeability, stomatal conductance, transpiration, net CO₂ assimilation, and total dry matter, in relation to distances from the emission source. In relation to the days of exposure, both species presented increased number of necrotic leaves and foliar phytotoxicity index, and decreased values in the chlorophyll analysis. The two native plant species, both of which occur in the Brazilian Restinga, showed damage when exposed to emissions from an iron ore pelletizing factory. C. hilariana was considered the most sensitive species due to the decreased values in a higher number of variables after exposition.

In ants, intra and inter-colony variation in body size can be considerable, even in monomorphic species. It has been previously shown that size-related parameters can be environmentally sensitive. The shape of the body size distribution curve is, however, rarely investigated. In this study, we measured head widthes of the black garden ant Lasius niger workers using digital methods. The ants were sampled from 51 colonies originating from 19 sites located along a metal pollution gradient, established in a former mining area in Poland. Total zinc concentrations in random samples of small invertebrates were used as a measure of site pollution levels. We found that the skewness of head size distribution grows significantly in line with the pollution level of the site, ranging from values slightly below zero (about −0.5) in the least polluted site up to a positive value (about 1.5) in the most polluted site. This result indicates that the frequency of small ants grows as pollution levels increase. The coefficient of variation, as well as the measures of central tendency, was not related to the pollution level. Four hypotheses explaining the obtained results are proposed. The bias towards the higher frequency of small workers may result from energy limitation and/or metal toxicity, but may also have an adaptive function.

The nitrifying/denitrifying activated sludge process removes several micropollutants from wastewater by sorption onto sludge and/or biodegradation. The objective of this paper is to propose and evaluate a lab-scale experimental strategy for the determination of partition coefficient and biodegradation constant for micropollutant with an objective of modelling their removal. Four pharmaceutical compounds (ibuprofen, atenolol, diclofenac and fluoxetine) covering a wide hydrophobicity range (log Kₒwfrom 0.16 to 4.51) were chosen. Dissolved and particulate concentrations were monitored for 4 days, inside two reactors working under aerobic and anoxic conditions, and under different substrate feed conditions (biodegradable carbon and nitrogen). We determined the mechanisms responsible for the removal of the target compounds: (i) ibuprofen was biodegraded, mainly under aerobic conditions by cometabolism with biodegradable carbon, whereas anoxic conditions suppressed biodegradation; (ii) atenolol was biodegraded under both aerobic and anoxic conditions (with a higher biodegradation rate under aerobic conditions), and cometabolism with biodegradable carbon was the main mechanism; (iii) diclofenac and fluoxetine were removed by sorption only. Finally, the abilities of our strategy were evaluated by testing the suitability of the parameters for simulating effluent concentrations and removal efficiency at a full-scale plant.

The purpose of this research is to develop a direct spectrometric approach to monitor soils and waters, at a lower cost than the widely used chromatographic techniques; a spectrometric approach that is effective, reliable, fast, easy to implement, and without any use of organic solvents whose utilization is subject to law limitation. It could be suitable at least as an alert method in case of massive contamination. Here, we present for the first time a catalog of excitation–emission and total synchronous fluorescence maps that may be considered as fingerprints of a series of homologated pesticides, in large use in Morocco, aiming at a direct detection of their remains in agricultural soils and neighboring waters. After a large survey among farmers, agricultural workers and product distributors in two important agricultural regions of Morocco (Doukkala-Abda and Sebou basin), 48 commercial pesticides, which are fluorescent, were chosen. A multi-component spectral database of these targeted commercial pesticides was elaborated. For each pesticide, dissolved in water at the lowest concentration giving a no-noise fluorescence spectrum, the total excitation-emission matrix (TEEM), the total synchronous fluorescence matrix (TSFM) in addition to synchronous fluorescence spectra (SFS) at those offsets giving the highest fluorescence intensity were recorded. To test this preliminary multi-component database, two real soil samples, collected at a wheat field and at a vine field in the region of Doukkala, were analyzed. Remains of the commercial Pirimor (Carbamate) and Atlantis (Sulfonylurea) were identified by comparison of the recorded TEEM, TSFM, and SFS to those of the preliminary catalog at one hand, and on the basis of the results of a field pre-survey. The developed approach seems satisfactory, and the fluorimetric fingerprint database is under extension to a higher number of fluorescent pesticides in common use among the Moroccan agricultural regions.

Gold nanoparticles (AuNPs) are considered an important nano-sized component of the twenty-first century. Due to their unique physical and chemical properties, they are being used and developed for a wide range of promising applications in medicine, biology and chemistry. Notwithstanding their useful aspects, in recent years concern has been raised over their ability to enter cells, organelles and nuclei and provoke oxidative stress. In a laboratory-based experiment, the non-target marine bivalve Ruditapes philippinarum was used as a model organism. Uptake, elimination and molecular effects under short-term and sub-chronic exposure conditions to an environmental relevant concentration (0.75 μg L⁻¹) of weakly agglomerating citrate AuNPs (∼20 nm) were studied. Our results demonstrate that at the tested concentration, the particles are readily taken up into the digestive gland > gills and can produce significant changes (p < 0.05) in oxidative stress and inflammatory response markers, as measured by phase II antioxidant enzymes and q-PCR gene expression analysis. However, the overall magnitude of responses was low, and oxidative damage was not provoked. Further, a significant elimination of Au from the digestive tract within a 7-day purification period was observed, with excretion being an important pathway. In conclusion, short-term and sub-chronic exposure to an environmental relevant concentration of citrate-stabilized AuNPs cannot be considered toxic to our model organism, while some further consideration should be given to chronic exposure effects.

Endophytic bacteria from roots and crude seed extracts of a Cu-tolerant population of Agrostis capillaris were inoculated to a sunflower metal-tolerant mutant line, and their influence on Cu tolerance and phytoextraction was assessed using a Cu-contaminated soil series. Ten endophytic bacterial strains isolated from surface-sterilized A. capillaris roots were mixed to prepare the root endophyte inoculant (RE). In parallel, surface-sterilized seeds of A. capillaris were crushed in MgSO₄to prepare a crude seed extract containing seed endophytes (SE). An aliquot of this seed extract was filtered at 0.2 μm to obtain a bacterial cell-free seed extract (SEF). After surface sterilization, germinated sunflower seeds were separately treated with one of five modalities: no treatment (C), immersion in MgSO₄(CMg) or SEF solutions and inoculation with RE or SE. All plants were cultivated on a Cu-contaminated soil series (13–1020 mg Cu kg⁻¹). Cultivable RE strains were mostly members of the Pseudomonas genera, and one strain was closely related to Labrys sp. The cultivable SE strains belonged mainly to the Bacillus genera and some members of the Rhodococcus genera. The treatment effects depended on the soil Cu concentration. Both SE and SEF plants had a higher Cu tolerance in the 13–517 mg Cu kg⁻¹soil range as reflected by increased shoot and root DW yields compared to control plants. This was accompanied by a slight decrease in shoot Cu concentration and increase in root Cu concentration. Shoot and root DW yields were more promoted by SE than SEF in the 13–114 mg Cu kg⁻¹soil range, which could reflect the influence of seed-located bacterial endophytes. At intermediate soil Cu (416–818 mg Cu kg⁻¹soil), the RE and CMg plants had lower shoot Cu concentrations than the control, SE and SEF plants. At high total soil Cu (617–1020 mg Cu kg⁻¹), root DW yield of RE plants slightly increased and their root Cu concentration rose by up to 1.9-fold. In terms of phytoextraction efficiency, shoot Cu removal was increased for sunflower plants inoculated with crude and bacterial cell-free seed extracts by 1.3- to 2.2-fold in the 13–416 mg Cu kg⁻¹soil range. Such increase was mainly driven by an enhanced shoot DW yield. The number and distribution of endophytic bacteria in the harvested sunflower tissues must be further examined.

Ambient air pollution is recognised as one of the potential environmental risk factors causing health hazards to the exposed population, demonstrated in numerous previous studies. Several longitudinal, ecological and epidemiological studies have shown associations between outdoor levels of outdoor atmospheric pollutants and adverse health effects, especially associated with respiratory and cardiovascular hospital admissions. The aim of this work is to assess the influence of atmospheric pollutants over the hospital admissions in Lisbon, by Ordinary Least Squares Linear Regression. The pollutants (CO, NO, NO₂, SO₂, O₃, PM₁₀and PM₂.₅) were obtained from 13 monitoring stations of the Portuguese Environmental Agency, which provide hourly observations. Hospital admission data were collected from the Central Administration of the Health System and were compiled by age: <15, 15–64, >64 years old. The study period was 2006–2008. Results showed significant positive associations between the following: (1) the pollutants CO, NO, NO₂, SO₂, PM₁₀and PM₂.₅and circulatory diseases for ages between 15 and 64 years (0.5 % hospital admissions (HA) increase with 10 μg m⁻³NO increase) and above 64 years (1.0 % stroke admission increase with 10 μg m⁻³NO₂increase); (2) the pollutants CO, NO, NO₂, SO₂, PM₁₀and PM₂.₅and respiratory diseases for ages below 15 years (up to 1.9 % HA increase with 10 μg m⁻³pollutant increase); and (3) the pollutants NO, NO₂and SO₂and respiratory diseases for ages above 64 years (1.3 % HA increase with 10 μg m⁻³CO increase).

Siderophores are chelators with a high selectivity for Fe(III) and a good affinity for divalent metals, including Cd(II) and Ni(II). Inoculation with siderophore-producing bacteria (SPB) has thus been proposed as an alternative to chelator supply in phytoremediation. Accurate assessments of the potential of this association require a dissection of the interaction of siderophores with metals at the soil–root interface. This study focuses on pyoverdine (Pvd), the main siderophore produced by Pseudomonas aeruginosa. We first assessed the ability of Pvd to coordinate Ni(II). The stability constant of Pvd–Ni(II) (log K ᴸ′ᴺⁱ = 10.9) was found to be higher than that of Pvd–Cd(II) (log K ᴸ′Cᵈ = 8.2). We then investigated the effect of a direct supply of Pvd on the mobilization, speciation, and phytoavailability of Cd and Ni in hydroponics. When supplied at a concentration of 50 μM, Pvd selectively promoted Ni mobilization from smectite. It decreased plant Ni and Cd contents and the free ionic fractions of these two metals, consistent with the free ion activity model. Pvd had a more pronounced effect for Ni than for Cd, as predicted from its coordination properties. Inoculation with P. aeruginosa had a similar effect on Ni phytoavailability to the direct supply of Pvd.