We assessed the state of knowledge regarding the effects of large-scale pollution with neonicotinoid insecticides and fipronil on non-target invertebrate species of terrestrial, freshwater and marine environments. A large section of the assessment is dedicated to the state of knowledge on sublethal effects on honeybees (Apis mellifera) because this important pollinator is the most studied non-target invertebrate species. Lepidoptera (butterflies and moths), Lumbricidae (earthworms), Apoidae sensu lato (bumblebees, solitary bees) and the section “other invertebrates” review available studies on the other terrestrial species. The sections on freshwater and marine species are rather short as little is known so far about the impact of neonicotinoid insecticides and fipronil on the diverse invertebrate fauna of these widely exposed habitats. For terrestrial and aquatic invertebrate species, the known effects of neonicotinoid pesticides and fipronil are described ranging from organismal toxicology and behavioural effects to population-level effects. For earthworms, freshwater and marine species, the relation of findings to regulatory risk assessment is described. Neonicotinoid insecticides exhibit very high toxicity to a wide range of invertebrates, particularly insects, and field-realistic exposure is likely to result in both lethal and a broad range of important sublethal impacts. There is a major knowledge gap regarding impacts on the grand majority of invertebrates, many of which perform essential roles enabling healthy ecosystem functioning. The data on the few non-target species on which field tests have been performed are limited by major flaws in the outdated test protocols. Despite large knowledge gaps and uncertainties, enough knowledge exists to conclude that existing levels of pollution with neonicotinoids and fipronil resulting from presently authorized uses frequently exceed the lowest observed adverse effect concentrations and are thus likely to have large-scale and wide ranging negative biological and ecological impacts on a wide range of non-target invertebrates in terrestrial, aquatic, marine and benthic habitats.

We assessed the state of knowledge regarding the effects of large-scale pollution with neonicotinoid insecticides and fipronil on non-target invertebrate species of terrestrial, freshwater and marine environments. A large section of the assessment is dedicated to the state of knowledge on sublethal effects on honeybees (Apis mellifera) because this important pollinator is the most studied non-target invertebrate species. Lepidoptera (butterflies and moths), Lumbricidae (earthworms), Apoidae sensu lato (bumblebees, solitary bees) and the section “other invertebrates” review available studies on the other terrestrial species. The sections on freshwater and marine species are rather short as little is known so far about the impact of neonicotinoid insecticides and fipronil on the diverse invertebrate fauna of these widely exposed habitats. For terrestrial and aquatic invertebrate species, the known effects of neonicotinoid pesticides and fipronil are described ranging from organismal toxicology and behavioural effects to population-level effects. For earthworms, freshwater and marine species, the relation of findings to regulatory risk assessment is described. Neonicotinoid insecticides exhibit very high toxicity to a wide range of invertebrates, particularly insects, and field-realistic exposure is likely to result in both lethal and a broad range of important sublethal impacts. There is a major knowledge gap regarding impacts on the grand majority of invertebrates, many of which perform essential roles enabling healthy ecosystem functioning. The data on the few non-target species on which field tests have been performed are limited by major flaws in the outdated test protocols. Despite large knowledge gaps and uncertainties, enough knowledge exists to conclude that existing levels of pollution with neonicotinoids and fipronil resulting from presently authorized uses frequently exceed the lowest observed adverse effect concentrations and are thus likely to have large-scale and wide ranging negative biological and ecological impacts on a wide range of non-target invertebrates in terrestrial, aquatic, marine and benthic habitats.

This study proposes an improved activation for hydrogen peroxide and persulfate using Fe-modified diatomite (MD) to favorably lead the reaction to generate hydroxyl and sulfate radicals to degrade the contaminants phenanthrene and anthracene. Diatomite was modified by impregnating it with a mixture of ferrous (Fe²⁺) and ferric (Fe³⁺) ions in the form of precipitated iron oxides and hydroxides. The raw and synthesized materials were characterized by powder X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size by laser diffraction, chemical microanalysis of the elements by energy-dispersive X-ray, and scanning electron microscopy (SEM). Batch experiments were performed to compare the new activator material (modified diatomite) with traditional methods of activation for these oxidants and to statistically study the optimum ratio between the amount of this material and the concentration of one oxidant to the degradation of the contaminants phenanthrene and anthracene. The characterization results showed that the materials are amorphous and that the Fe ion concentration was 4.78 and 17.65 % for the raw and modified diatomites, respectively. This result shows a significant increase in the amount of iron ions after synthesis. Comparing the traditional activation method with the modified diatomite, the results of batch experiments showed that the synthesized material presents significant catalytic activity for the oxidation of these contaminants, using sodium persulfate and hydrogen peroxide as oxidants. The analysis of the variables results showed that the concentration of the oxidant has higher significance than the amount of the catalyst.

The presence of multicomponent nonaqueous phase liquid (NAPL) source zones in the subsurface can significantly complicate remediation efforts, transport predictions, and the development of accurate risk assessments. A series of flow-cell experiments was conducted to investigate the effectiveness of two different enhanced-solubilization agents for the removal of a multicomponent dense nonaqueous phase liquid (DNAPL) source zone from homogeneous porous media. The source zone consisted of an equal 1:1:1 mole mixture of cis-1,2-dichloroethene (DCE), trichloroethene (TCE), and tetrachloroethene (PCE) with NAPL saturation (Sn) targeted between 8 and 14 %. Solutions (5 wt%) of hydroxypropyl-β-cyclodextrin (HPCD) and sodium dodecyl sulfate (SDS) were flushed through the flow-cell system until nearly complete contaminant removal was achieved. Analysis of elution curves indicate that SDS was approximately 10 times more efficient at removing all three components from the system compared to HPCD. Although enhancement factor magnitudes vary for each specific contaminant component and enhanced-solubilization agent, the lowest-solubility contaminant component (i.e., PCE) consistently experienced the greatest relative solubility enhancement during flushing. SDS was generally superior when evaluated on a recovery basis; however, HPCD outperformed SDS for all contaminant components when compared based on moles-contaminant to moles-reagent removal efficiency analysis. Contaminant mass flux reduction analysis showed that enhanced-solubilization flushing (HPCD and SDS) resulted in general inefficient contaminant removal behavior. Raoult’s Law could be used to successfully predict aqueous contaminant concentrations from the multicomponent DNAPL source zone, indicating that dissolution processes were relatively ideal during both HPCD and SDS enhanced-solubilization flushing. These findings suggest that multicomponent NAPL source dissolution and removal depend upon the flushing agent itself and of the solubility and properties of the individual components of the NAPL mixture. The selection of a particular enhanced-flushing agent should be evaluated carefully prior to remediation as the dissolution, removal, and mass flux behavior of each component can vary significantly.

The feasibility of cyanobacteria removal from freshwater by a dielectric barrier discharge (DBD) process is investigated. Seven commercial and environmental cyanobacteria strains, as well as real algae-laden water, were tested. The removal of the cyanobacteria was evaluated by analyzing the changes in chlorophyll a content, total organic carbon (TOC) concentration, and cell morphology. Nearly total removal of chlorophyll a was achieved within 20 min, while the TOC analysis exhibited an increase-decrease-increase trend in 60 min of treatment, likely due to the oxidation of intracellular and intercellular materials. Observation under light microscopy revealed the disruption of intracellular and intercellular structures within 5 min of DBD treatment and thus supported the TOC analysis. Increasing the salinity of the medium from 0 to 5 parts per thousand (ppt) improved treatment efficiency, where similar level of chlorophyll a removal (around 93 %) was achieved in only half the treatment time. Application of DBD on real algae-laden water from a fish farm yielded higher treatment efficiency than in synthetic medium, indicating the promising application of DBD as a means to control cyanobacteria bloom in fresh and estuary water bodies.

Early-life exposure to pollutants, such as lead, may have long-lasting consequences on health, behavior, and cognition. However, experiments on delayed effects of specific pollutants are very rare in wild animals. We experimentally exposed wild nestling great tits (Parus major) to dietary lead (high, low, or control group) in levels relevant to exposure levels of wild populations in Europe and studied delayed effects on phenotypic and behavioral traits in captivity. We also included a group of birds from a vicinity of a copper smelter, exposed to a mixture of toxic metals and altered food supply during development. This experimental setup allowed us to compare the strength of direct (exposure to lead per se) and indirect (pollution-related changes in diet) effects of pollutants. Our experimental lead treatment significantly increased lead levels in bone and feces compared with controls. However, we found no carry-over effect of early-life dietary lead on morphology, plumage coloration, or heat shock proteins. Treatment did not affect activity, exploration, neophobia, or success in learning and spatial memory task. We conclude that with the exposure levels and relatively short exposure period used, delayed effects on the measured traits were not found. However, it is important to further study other types of behavioral traits and ultimately fitness effects.

To treat PCP-contaminated soil, abiotic methods for PCP degradation have been developed, where heme or powder hemoglobin acts as a catalyst and hydrogen peroxide as an oxidant. Degradation of PCP had the first-order kinetics, and rate coefficients, k, were 0.073 and 0.104/day for heme and hemoglobin, respectively, indicating that the hemoglobin was a more efficient catalyst than heme. Approximately 96 % of the initial PCP was degraded at day 35. Thus, hemoglobin might be recommended as the catalyst of choice, since it is much less expensive than heme.

Many products contain dyes, such as fabrics. However, most of the industry-generated waste is improperly handled, which causes serious environmental problems for the bodies of water that receive textile effluents. This study aimed to analyze the effect of biosorbents and biosorption techniques on decolorizing the textile azo dye Acid Blue 29 in an aqueous solution employing pine sawdust. Pine sawdust is low-cost substrate with minor environmental impact. A toxicity test was performed with Lactuca sativa seeds to determine the LC₅₀ of the dye. Subsequently, a biosorption test was performed to determine the toxicity of the resulting solutions. We observed that biosorption is a very feasible technique for the discoloration of the solutions and promotes reduction in their toxicity.

Soil is a primary resource used by mankind to ensure its needs mainly through agriculture. Its sustainability is regulated by the indigenous organisms it contains such as microorganisms. Current agricultural practices employ mixtures of pesticides to ensure the crops yield and can potentially impair these non-target organisms. However despite this environmental reality, studies dealing the susceptibility of microorganisms to pesticide mixtures are scarce. In this context, we designed a 3-month microcosm study to assess the ecotoxicity of realistic herbicide mixtures of formulated S-metolachlor (Dual Gold Safeneur®), mesotrione (Callisto®), and nicosulfuron (Milagro®) on the abundance, the diversity, and the activities of microorganisms from a “clay/organic matter-rich” soil, with a particular attention given to N-cycle communities. These communities appeared to be quite resistant to realistic mixtures even if transient effects occurred on the N-cycle-related communities with an increase of ammonification and an inhibition of nitrification as a short-term effect, followed by an increase of denitrification and an accumulation of nitrates. As nitrates are known to be highly leachable with a strong pollution potential, intensive studies should be carried out at field level to conclude on this potential accumulation and its consequences. Moreover, these data now need to be compared with other agricultural soils receiving these herbicide mixtures in order to bring general conclusion on such practices.

Poultry litter and bedding materials generated from laying chicken farm often contain high levels of arsenic when roxarsone is included in feed to combat disease and improve egg production. This study was conducted to determine the fate and ecological risk of arsenic species in poultry litter which applied to agricultural field. Three poultry litter application rates (0, 10, 60 % dry weight) were used to amend soil samples under anaerobic and aerobic circumstances, respectively, incubated at 30 % moisture content for 110 days. Experiment indicated that under anaerobic circumstance, As(V) and As(III) decreased in treatments applied 60 and 10 % rates within initial 7 days, subsequently methylated arsenic displayed increasing, suggesting biotic activity transformed inorganoarsenical to methylated arsenic species. In contrast, As(V) dropped in the first 7 days but increased thereafter under aerobic circumstances, with methylated arsenic increasing, implying abiotc and biotic activities enhanced arsenic speciation. Based on different arsenic species, we evaluated their ecological risk in poultry litter respectively. It was found that ecological risks under anaerobic circumstance were higher than under aerobic circumstance of the same poultry litter rates, and higher poultry litter rates applied to soil would bring about higher ecological risk. We suggest that poultry litter should be disposed at low rate (approximately 10 %) and applied to soil surface to create aerobic circumstance for the initial 2 months time, but should be buried into a deeper depth thereafter.