AMEG: the new SETAC advisory group on aquatic macrophyte ecotoxicology

Introduction and background

Primary producers play critical structural and functional roles in aquatic ecosystems; therefore, it is imperative that the potential risks of toxicants to aquatic plants are adequately assessed in the risk assessment of chemicals. The standard required macrophyte test species is the floating (non-sediment-rooted) duckweed Lemna spp. This macrophyte species might not be representative of all floating, rooted, emergent, and submerged macrophyte species because of differences in the duration and mode of exposure; sensitivity to the specific toxic mode of action of the chemical; and species-specific traits (e.g., duckweed's very short generation time).

Discussion and perspectives

These topics were addressed during the workshop entitled “Aquatic Macrophyte Risk Assessment for Pesticides” (AMRAP) where a risk assessment scheme for aquatic macrophytes was proposed. Four working groups evolved from this workshop and were charged with the task of developing Tier 1 and higher-tier aquatic macrophyte risk assessment procedures. Subsequently, a SETAC Advisory Group, the Macrophyte Ecotoxicology Group (AMEG) was formed as an umbrella organization for various macrophyte working groups. The purpose of AMEG is to provide scientifically based guidance in all aspects of aquatic macrophyte testing in the laboratory and field, including prospective as well as retrospective risk assessments for chemicals. As AMEG expands, it will begin to address new topics including bioremediation and sustainable management of aquatic macrophytes in the context of ecosystem services.     

Separate waste collection in Italy: the role of socio-cultural factors and targets set by law

The aim of this paper was twofold: on the one hand, we analyse the results achieved in terms of percentages of separate collection in Italy by testing the effectiveness of Legislative Decree 152/2006 in improving the separate collection process; and on the other hand, we investigate on some of the factors, related to the sociocultural local context, that could explain the different impacts of the law in the three macro-areas considered (North, Central and South Italy). To this purpose, an econometric analysis on the Italian regions for the 1996–2013 period is performed, comparing the period before (1996–2006) and after (2006–2013) the date of entry into force of the new law. The results show the effectiveness of Legislative Decree 152/2006 in promoting separate collection, although a regional difference in terms of separate collection rate is observed. Northern regions proved to be more dynamic and reactive to the above-mentioned legislation, while Central and especially Southern regions achieved poorer results in moving to higher separate waste collection rates. Finally, our work provides evidence on some local factors that may have hampered an effective policy implementation in Southern regions, among them, the presence of criminal activities and the lack of citizen participation in politics.     

Wildfire,climate, and perceptions in Northeast Oregon

Regional Environmental Change - Wildfire poses a rising threat in the western USA, fueled by synergies between historical fire suppression, changing land use, insects and disease, and shifts toward...     

Peroxymonosulfate-Co(II) oxidation system for the removal of the non-ionic surfactant Brij 35 from aqueous solution

The non-ionic surfactant Brij 35 was effectively removed from concentrated aqueous solution by the peroxymonosulfate/Co(II) system, using oxone (2KHSO₅·KHSO₄·K₂SO₄) as a source of peroxymonosulfate. At pH = 2.3 and initial Brij 35 concentration in the range 680-2410 mg L⁻¹, 86-94% removal was achieved after 24 h, using Co(II) = 15 μM and oxone = 5.9 mM. The effectiveness of removal did not change when initial pH was in the range 2.3-8.2. After five subsequent additions of Co(II) and oxone to the solution, COD and TOC removals increased up to 64% and 33%, respectively. Radical quenching tests confirmed that sulfate radical was the dominant radical species in the system. The main identified by-products from surfactant degradation were: (a) low molecular weight organic acids; (b) aldehydes and formates with shorter ethoxy chain than Brij 35; (c) alcohol ethoxylates carrying hydroxyl groups bonded to ethoxy chain. By-products identification allowed to hypothesize the pathways of Brij 35 degradation.     

Identification of fungal proteases potentially suitable for environmentally friendly cleaning-in-place in the dairy industry

Fourteen fungi were screened for ability to produce proteases with activity on milk protein. The proteases produced were assessed on a lab-scale in terms of their potential suitability for cleaning-in-place (CIP) in the dairy industry. Cleaning performance was assessed by determining the ability of the enzymes to remove an industrial-like milk fouling deposit from stainless steel. Based on the results observed, the extracellular protease activity produced by Schizophyllum commune was selected as most suitable for potential CIP application. A CIP procedure involving a sodium carbonate rinse followed by enzymatic cleaning with this fungal enzyme activity was developed. Satisfactory cleaning, judged by quantification of residual organic matter and protein on the stainless steel surface after cleaning, was achieved using the developed CIP procedure at 40 °C. This CIP procedure, based on biodegradable enzymes working at low temperature is more environmentally favourable than conventional CIP methods using caustic based cleaning solutions at 70-80 °C. Potential environmental benefits of the developed enzymatic CIP procedure include reduced energy consumption, decreased chemical usage and a reduced requirement for pH neutralisation of the resultant waste prior to release.     

Biogenic volatile organic compounds as a potential stimulator for organic contaminant degradation by soil microorganisms

The effects of monoterpenes on the degradation of ¹⁴C-2,4-dichlorophenol (DCP) were investigated in soils collected from areas surrounding monoterpene and non-monoterpene-emitting vegetation. Indigenous microorganisms degraded ¹⁴C-2,4-DCP to ¹⁴CO₂, after 1 d contact time. Degradation was enhanced by prior exposure of the soils to 2,4-DCP for 32 d, increasing extents of mineralisation up to 60%. Monoterpene amendments further enhanced 2,4-DCP degradation, but only following pre-exposure to both 2,4-DCP and monoterpene, with total 2,4-DCP mineralisation extents of up to 71%. Degradation was greatest at the higher monoterpene concentrations (≥1 μg kg⁻¹). Total mineralisation extents were similar between concentrations, but higher than the control and the 0.1 μg kg⁻¹ amendment, indicating that increases in monoterpene concentration has a diminishing enhancing effect. We suggest that monoterpenes can stimulate the biodegradation of 2,4-DCP by indigenous soil microorganisms and that monoterpene amendment in soils is an effective strategy for removing organic contaminants.     

Population-level toxicity of the insecticide, spinosad and the nonylphenol polyethoxylate, R-11, to the cladoceran species Ceriodaphnia dubia Richard

The effects of the natural insecticide, spinosad, and the agricultural adjuvant, R-11, were evaluated on populations of the water flea, Ceriodaphnia dubia after chronic 8-day exposures. The number of individuals used to start the chronic exposure studies (founders) and the number of offspring/surviving female were significantly reduced after exposure to spinosad concentrations ≥ 2.5 μg/L. The final number of individuals was significantly reduced after exposure to spinosad concentrations ≥ 1.0 μg/L. Population growth rate was significantly reduced after exposure to spinosad concentrations ≥ 1 μg/L. Extinction occurred (defined as negative population growth rate) after exposure to spinosad concentrations of 10 μg/L. Therefore, negative effects were observed in C. dubia after exposure to spinosad at a concentration near the chronic expected environmental concentration (EEC) of 2.3 μg/L. R-11 was much less toxic to C. dubia than spinosad. The number of founders was not significantly reduced until C. dubia were exposed to 12,000 μg/L. The number of offspring/surviving female, final number of individuals, and population growth rate were significantly reduced after exposure to R-11 concentrations ≥ 5,000 μg/L. Extinction occurred after exposure to R-11 concentrations of 12,000 μg/L which was above the EEC of 790 μg/L. These results indicate that spinosad and R-11 both have lethal and sublethal effects on C. dubia. However, spinosad appears to affect C. dubia at or near the EEC while R-11 does not negatively affect this species until concentrations are much higher than the EEC.     

Towards an ecologically meaningful classification of the flow biotope for river inventory, rehabilitation, design and appraisal purposes

Recent research into the physical and ecological status of rivers has focused upon rapid field-based assessments of mesoscale habitat features in order to satisfy international regulatory requirements for habitat inventory and appraisal. Despite the low cost and time efficient nature of rapid field surveys, the robustness of such techniques remains uncertain. This paper uses data from over 4000 surveyed UK river reaches in the UK River Habitat Survey (RHS) database in order to seek linkages between surface flow conditions (flow biotopes), local channel morphology (physical biotopes) and biologically distinct vegetative and minerogenic habitat units (functional habitats). Attempts to identify one-to-one connections between surface flow types, units of channel morphology and functional habitats oversimplify a complex and dynamic hydraulic environment. Instead, a nested hierarchy of reach-scale physical and ecological habitat structures exists, characterised by transferable assemblages of habitat units. Five flow biotopes show strong correlations with functional habitats, and differing combinations of three of these account for over 60% of the distribution for all functional habitats. On this basis, a classification of environments for ecological purposes is proposed. Principal components analysis and agglomerative hierarchical clustering analysis are employed to objectively validate the proposed classification. Flow biotope assemblages may also represent reach-scale channel morphologies (step-pool, riffle-pool and glide-pool), although functional habitats exhibit differing 'preferences' for rougher or more tranquil environments within these. While the data and analysis are specific to the UK RHS, the methods and findings have wider application in situations, where rapid field appraisal methods and associated databases are deployed in water resource inventory and river rehabilitation design.     

Quantitative modelling of Ostracod bioassay: assigning toxicity index to potentially chemical contaminated swimming pools

Environmental Science and Pollution Research - One of the primary objectives of any public health programme is to design a protocol that will curtail a population from being predisposed to toxic...