Challenges and opportunities for the environmental risk assessment of chemicals in soils: a recap and follow-up of a setac webinar.

Soil sustainability is unquestionable but is under various threats, one of which includes chemical pollution. Under the vision of reaching healthy soils by 2050, the SETAC Webinar "Assessing Risks in Soil: Challenges and Opportunities" was held to understand the current state of soil health in Europe and, identify gaps in the environmental risk assessment (ERA) framework for chemicals entering soils. In reflection of the webinar and soil protection, strategies to describe the current state of soils, including knowledge on existing chemical pollution in soils and soil biodiversity metrics are discussed.

Effects of tire particles on earthworm (Eisenia andrei) fitness and bioaccumulation of tire-related chemicals.

Tire and Road Wear Particles (TRWP) are produced during the wear of tire rubber on the road pavement and contain various chemicals originating from the road environment and from the rubber. Toxic effects of TRWP and their associated chemicals on soil organisms remain poorly characterized. In a series of laboratory experiments, this study investigated the bioaccumulation kinetics of several common tire-related chemicals in the earthworm species Eisenia andrei using Cryogenically Milled Tire Tread (CMTT), as a surrogate for environmental TRWP.

Incorporation of sediment- and soil-specific aspects in the Criteria for Reporting and Evaluating Ecotoxicity Data (CRED).

In environmental risk assessment either for registration purposes or for retrospective assessments of monitoring data, the hazard assessment is predominantly based on effect data from ecotoxicity studies. Most regulatory frameworks require studies used for risk assessment to be evaluated for reliability and relevance. Historically, the Klimisch methodology was used in many regulatory procedures where reliability needed to be evaluated.

The upcoming European Soil Monitoring Law: An effective instrument for the protection of terrestrial ecosystems?

Soils are a precious resource consistently placed under several threats and urgently in need of protection within a regulatory framework at the European level. Soils are central to the provision of environmental services as well as human existence on earth. The need to protect soil has been identified by several recent European strategies and fortunately, a specific European regulation for soil protection is on the way-the European Soil Monitoring Law (formerly: Soil Health Law).

Response addition is more protective of biogeochemical cycles of carbon and phosphorus compared to concentration addition.

In soils, enzymes are crucial to catalyzing reactions and cycling elements such as carbon (C), nitrogen (N), and phosphorus (P). Although these soil enzymes are sensitive to metals, they are often disregarded in risk assessments, and regulatory laws governing their existence are unclear. Nevertheless, there is a need to develop regulatory standards for metal mixtures that protect biogeochemical cycles because soil serve as a sink for metals and exposures occur as mixtures.

The Recolonization Concentration Concept: Using Avoidance Assays with Soil Organisms to Predict the Recolonization Potential of Contaminated Sites.

In this study the recolonization concentration concept for soil organisms is presented and validated. This concept is based on the empirically deduced avoidance-recolonization hypothesis, which shows a negative correlation between avoidance (AC) and recolonization (RC) (AC = RC) responses. The concept was validated in a two-step approach composed by (i) individual placement tests, to demonstrate the non-influence of individual placement in a dual chamber avoidance test and (ii) small scale gradient tests to demonstrate that the number of colonizers reaching a soil patch with a certain concentration is independent on their previous exposure to lower concentrations.

Are structural and functional endpoints of soil communities similarly affected by metal mixtures? - A terrestrial model ecosystem approach.

Soils are habitat to a variety of flora and fauna in a linked ecosystem which provides essential ecosystem services. In soil, metals can accumulate at high concentrations, because of anthropogenic activities, leading to toxic effects, threatening the ecosystem and the services it provides. In most real-world contamination scenarios, metals occur as complex mixtures which can interact and produce different toxicity than predicted from individual metal data.

Community effect concentrations as a new concept to easily incorporate community data in environmental effect assessment of complex metal mixtures.

The goal of this study was to incorporate community data into the effect assessment of environmental and regulatory relevant metal mixtures. In this experiment three fixed mixture ratios (Canadian soil quality guideline ratio - CSQG; Agricultural, residential and Loamy ratio - ARL; and Sudbury ratio - SUD) were tested in a natural community microcosm with 11 doses for each mixture ratio. The effect of metal mixtures on the community was measured using the community effect concentration (EC) concept which assumes that as contamination increases, the community similarity between test and control treatments decreases producing a dose response curve allowing the calculation of community effect concentrations.

The effects of complex metal oxide mixtures on three soil invertebrates with contrasting biological traits.

For regulatory purposes, the concentration addition model is the default first tier for assessing joint-action toxicity of metal mixtures. Although many researchers have evaluated binary and ternary mixtures, fewer have investigated joint-action toxicity in more complex mixtures, where deviations from additivity are more likely due to the greater number of potential interactions. In this study, we tested fixed ratios of five metals (lead, copper, nickel, zinc, cobalt) as metal oxide mixtures on three soil invertebrate species (Enchytraeus crypticus, Folsomia candida, Oppia nitens) at different dose effect levels (EC10-EC90) in an acid sandy forest and a loamy soil.

Metal oxides and annealed metals as alternatives to metal salts for fixed-ratio metal mixture ecotoxicity tests in soil.

In soil metal ecotoxicology research, dosing is usually performed with metal salts, followed by leaching to remove excess salinity. This process also removes some metals, affecting metal mixture ratios as different metals are removed by leaching at different rates. Consequently, alternative dosing methods must be considered for fixed ratio metal mixture research.

Single metal and metal mixture toxicity of five metals to Oppia nitens in five different Canadian soils.

Metal mixture toxicity across soil types is a daunting challenge to risk assessment. Here, we evaluated metal mixture toxicity in Oppia nitens, using ten fixed metal mixture ratios in five Canadian soils that closely matched some of the EU PNEC reference soils. Soils were dosed with five metals (Cu, Zn, Pb, Co, Ni) as single metals (ten concentrations) and as mixtures (eight concentrations).

Toxicity assessment of metal mixtures to soil enzymes is influenced by metal dosing method.

Metals are present as mixtures in the environment, yet testing such complex mixture poses design and technical challenges. One possible solution is the use of fixed ratios, i.e.

Exploring the Use of Species Sensitivity Distributions to Define Protective Limits for the Use of Organic Wastes as Soil Amendments.

The use of organic wastes as soil amendments can be an important measure to improve soil quality and reduce waste accumulation and landfilling. However, the potential contaminant loads of such wastes, can be a source of environmental concern. Consequently, legislation has been developed to regulate the use of these wastes in agricultural soils.

From laboratory to the field: Validating molecular markers of effect in Folsomia candida exposed to a fungicide-based formulation.

Under controlled laboratory conditions, toxicity data tend to be less variable than in more realistic in-field studies and responses may thus differ from those in the natural environment, creating uncertainty. The validation of data under environmental conditions is therefore a major asset in environmental risk assessment of chemicals. The present study aimed to validate the mode of action of a commercial fungicide formulation in the soil invertebrate F.

Effects of the neonicotinoids acetamiprid and thiacloprid in their commercial formulations on soil fauna.

Neonicotinoids are the most prominent group of insecticides in the world and are commercialized in over 120 countries for the control of agricultural pests mainly due to their broad-spectrum activity and versatility in application. Though non-target soil organisms are likely to be exposed during application, there is paucity of information in scientific literature regarding their sensitivity to neonicotinoids. This study attempts to fill this gap by evaluating, under laboratory conditions, the chronic toxicity of the neonicotinoids thiacloprid and acetamiprid, through their commercial formulations (CF), to the soil invertebrates Folsomia candida, Eisenia andrei and Enchytraeus crypticus.

Organic wastes as soil amendments - Effects assessment towards soil invertebrates.

Using organic wastes, as soil amendments, is an important alternative to landfilling with benefits to soil structure, water retention, soil nutrient and organic matter concentrations. However, this practice should be monitored for its environmental risk due to the frequent presence, of noxious substances to soil organisms. To evaluate the potential of eight organic wastes with different origins, as soil amendments, reproduction tests with four soil invertebrate species (Folsomia candida, Enchytraeus crypticus, Hypoaspis aculeifer, Eisenia fetida) were performed using gradients of soil-waste mixtures.

Biomass Increases Go under Cover: Woody Vegetation Dynamics in South African Rangelands.

Woody biomass dynamics are an expression of ecosystem function, yet biomass estimates do not provide information on the spatial distribution of woody vegetation within the vertical vegetation subcanopy. We demonstrate the ability of airborne light detection and ranging (LiDAR) to measure aboveground biomass and subcanopy structure, as an explanatory tool to unravel vegetation dynamics in structurally heterogeneous landscapes. We sampled three communal rangelands in Bushbuckridge, South Africa, utilised by rural communities for fuelwood harvesting.

Lightweight GPS-tags, one giant leap for wildlife tracking? An assessment approach.

Recent technological improvements have made possible the development of lightweight GPS-tagging devices suitable to track medium-to-small sized animals. However, current inferences concerning GPS performance are based on heavier designs, suitable only for large mammals. Lightweight GPS-units are deployed close to the ground, on species selecting micro-topographical features and with different behavioural patterns in comparison to larger mammal species.

Object-Based Classification of Ikonos Imagery for Mapping Large-Scale Vegetation Communities in Urban Areas.

Effective assessment of biodiversity in cities requires detailed vegetation maps.To date, most remote sensing of urban vegetation has focused on thematically coarse landcover products. Detailed habitat maps are created by manual interpretation of aerialphotographs, but this is time consuming and costly at large scale.