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The toxicity of neonicotinoids and many of their replacement insecticides to nontarget soil invertebrates such as earthworms has previously been established. However, the long‐term effects of these substances on these organisms are largely unknown. In the field of soil ecotoxicology, lumbricid earthworms such as Eisenia andrei are used extensively due to the availability of standardized test methods and their adaptability to laboratory culture and testing. Multigenerational studies have gained popularity and attention in recent years, with a shift toward the use of long‐term assays and lower concentrations of test chemicals. The use of exposure concentrations that include those measured in a monitoring program carried out by the Government of Ontario presents a realistic exposure scenario that may not show significant effects in contemporary, shorter term studies. We used current standardized test methods as a basis for the development of multigenerational studies on E. andrei. The effects of exposure to a single application of the insecticides thiamethoxam and cyantraniliprole on the survival and reproduction of E. andrei were observed over three (thiamethoxam) or two (cyantraniliprole) generations using consecutive reproduction tests. No significant impacts on adult survival were reported in any generation for either insecticide, whereas reproduction decreased between the first and second generations in the thiamethoxam test, with median effective concentration (EC50) values of 0.022 mg/kg dry weight reported for the first generation compared with 0.002 mg/kg dry weight in the second generation. For cyantraniliprole, an EC50 of 0.064 was determined for the first generation compared with 0.016 mg/kg dry weight in the second generation. A third generation was completed for the thiamethoxam test, and a significant decrease in reproduction was observed in all treatments and controls compared with previous generations. No significant difference between thiamethoxam treatments and the control treatment was reported for the third generation. Collectively, these data indicate that exposure of oligochaetes to these two insecticides at concentrations representative of field conditions may result in long‐term stresses. Environ Toxicol Chem 2024;43:2058–2070. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Neonicotinoids have been among the most widely and abundantly used insecticides for most of the current century. The effects of these substances on nontarget terrestrial and aquatic organisms have resulted in a significant decrease in their use in many parts of the world. In response, the application of several novel classes of insecticides including diamides, ketoenols, pyridines, and butenolides has significantly increased. The hexapod subclass Collembola is an ecologically significant and widely distributed group of soil invertebrates often found in leaf litter and in surficial soils. We exposed the parthenogenic collembolan species Folsomia candida to six insecticides in a sandy loam soil for 28 days, including two neonicotinoids (thiamethoxam and clothianidin), a diamide (cyantraniliprole), a ketoenol (spirotetramat), a pyridine (flonicamid), and a butanolide (flupyradifurone) to assess the effect of each insecticide on survival and reproduction. Clothianidin, thiamethoxam, and cyantraniliprole (median effective concentration [EC50] values for reproduction: 0.19, 0.38, and 0.49 mg/kg soil, respectively) had a greater effect on survival and reproduction of F. candida than flupyradifurone, spirotetramat, and flonicamid (EC50 values for reproduction: 0.73, >3.08, and 5.20 mg/kg soil, respectively). All significant impacts found in our study were observed at concentrations below concentrations of the active ingredients that would be expected in agricultural soils. Environ Toxicol Chem 2023;42:1516–1528. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

The development of modern, industrial agriculture and its high input–high output carbon energy model is rendering agricultural landscapes less resilient. The expected continued increase in the frequency and intensity of extreme weather events, in conjunction with declining soil health and biodiversity losses, could make food more expensive to produce. The United Nations has called for global action by establishing 17 sustainable development goals (SDGs), four of which are linked to food production and security: declining biodiversity (SDG 15), loss of ecosystem services and agroecosystem stability caused by increasing stress from food production intensification and climate change (SDG 13), declining soil health caused by agricultural practices (SDGs 2 and 6), and dependence on synthetic fertilizers and pesticides to maintain high productivity (SDG 2). To achieve these SDGs, the agriculture sector must take a leading role in reversing the many negative environmental trends apparent in today's agricultural landscapes to ensure that they will adapt and be resilient to climate change in 2030 and beyond. This will demand fundamental changes in how we practice agriculture from an environmental standpoint. Here, we present a perspective focused on the implementation of an agrosystem approach, which we define to promote regenerative agriculture, an integrative approach that provides greater resilience to a changing climate, reverses biodiversity loss, and improves soil health; honors Indigenous ways of knowing and a holistic approach to living off and learning from the land; and supports the establishment of emerging circular economies and community well‐being. Integr Environ Assess Manag 2022;18:1199–1205. © 2021 SETAC Key Points: The agrosystem approach promotes regenerative agriculture, an integrative approach that can provide greater resilience to a changing climate, reverse biodiversity loss, and improve soil health.The agrosystem approach honors Indigenous ways of knowing and a holistic approach to living off and learning from the landThe agrosystem approach supports the establishment of emerging circular economies and community well‐being [ABSTRACT FROM AUTHOR]

Litter inputs to headwater streams were measured to characterize and describe input patterns to the streams and to quantify the relationships between leaf litter inputs and surrounding riparian characteristics in Boreal Shield forests. Our goal was to provide information on litter inputs to streams in the Boreal Shield to determine if partial-harvest logging of commercial trees within riparian reserves has the potential to cause significant changes to litter inputs. Total leaf litter comprised 87% deciduous leaves and 13% conifer needles during the June to October periods. Commercial deciduous tree species accounted for approximately 50% of total deciduous leaf litter inputs. Distance-weighted deciduous basal area was the best predictor of overstorey deciduous litter ([r.sup.2] = 0.597, P = Les apports de litiere dans les cours d'eau de tete ont ete mesures pour caracteriser et decrire le profil de ces apports dans les cours d'eau et quantifier les relations entre les apports de litiere de feuilles et les caracteristiques riveraines environnantes dans les forets du bouclier boreal. Notre but etait de fournir de l'information au sujet des apports de litie re dans les cours d'eau du bouclier boreal pour determiner si une coupe partielle des tiges marchandes dans les bandes riveraines peut entrainer des changements significatifs dans les apports de litiere. La litiere de feuilles totale etait compose e de 87 % de feuilles d'essences feuillues et de 13 % d'aiguilles de coniferes durant la periode allant de juin a octobre. Les especes feuillues marchandes representaient approximativement 50 % de toute la litiere de feuilles provenant d'essences feuillues. La surface terriere des essences feuillues ponderee par la distance etait le meilleur predicteur de la litiere des essences feuillues de l'etage dominant ([r.sup.2] = 0,597, P =, Introduction Riparian zones are defined as three-dimensional areas that directly link aquatic and terrestrial ecosystems (Gregory et al. 1991; Naiman et al. 2005). The structure and function of small forested [...]

Simple analytical methods were developed for the extraction and determination of four pharmaceuticals and personal care products (PPCPs) from water, sediments, and biota. PPCPs were determined using tandem LC-MS in electrospray ionization mode, and interactions with matrix co-eluents were investigated. Extractions of water samples were performed using solid-phase extraction (SPE), sediments were extracted by pressurized liquid extraction (PLE), and biota was extracted by liquid extraction. The selected analytical methods yielded recoveries ≥ 61% in all matrixes. Matrix interactions were investigated throughout the linear range of quantification of each compound, revealing that dissolved salts had relatively minor effects on ionization (between 14% suppression to 12% enhancement), but that sediment and biota extracts caused significant matrix effects (ranging from 56% suppression to 25% enhancement). The direction and magnitude of matrix interactions reflected the physico-chemical properties of each analyte, particularly their p[K.sub.a]. Among the compounds analyzed in electrospray positive mode, carbamazepine was insensitive to matrix interactions, because it is a strong proton acceptor (p[K.sub.a] = 14.0). In contrast, atorvastatin (p[K.sub.a] = 4.5), a weaker proton acceptor, was particularly sensitive to matrix effects. For those compounds analyzed in negative-ion mode, sample alkalinity was found to be important. With a p[K.sub.a] of 10.4, 17α-ethinylestradiol generally exhibited matrix enhancement with increased sample alkalinity. However, the presence of acidic co-eluents contributed to matrix suppression. Lastly, TCS was particularly sensitive to matrix suppression, as its circumneutral p[K.sub.a] (7.9) caused even slight changes in sample pH to considerably impact ionization. We conclude that while different matrixes have clear impacts on ionization of these PPCPs, matrix effects can be quantified and overcome. Key words: pharmaceuticals and personal care products, matrix effects, LC-MS/MS, sediments, biota. On a developpe des methodes analytiques simples pour l'extraction et la determination de quatre produits pharmaceutiques et de soins personnels (PPSP) a partir de solutions aqueuses, de sediments et du biote. On a determine les PPSP en faisant appel a la chromatographie liquide operant en tandem avec spectrometrie de masse en mode d'ionisation par electronebulisation (CL-SM) et on a etudie les interactions avec les coeluants de la matrice. Les extractions a partir de solutions aqueuses ont ete effectuees en utilisant l'extraction en phase solide (EPS) alors que les sediments ont ete soumis a une extraction avec un liquide pressurise (ELP) et que le biote a ete soumis a une extraction liquide. Dans l'ensemble des matrices, les methodes analytiques choisies ont permis d'obtenir des taux de recuperation d'au moins 61%. On a etudie les interactions avec la matrice pour la plage entiere de quantification de chaque compose et ces etudes ont revele que les sels dissous n'ont que des effets mineurs sur l'ionisation (allant de 14% de suppression a 12% de renforcement); toutefois, dans les cas des extractions des sediments et du biote, on observe des effets de matrice importants allant de 56% de suppression a 25% de renforcement. La direction et l'amplitude des interactions de matrice sont des reflets des proprietes physico-chimiques de chaque analyte, en particulier de leur p[K.sub.a]. Parmi les composes analyses en mode d'electronebulisation positive, la carbamazepine est insensible aux interactions de matrice du au fait qu'il s'agit d'un produit fortement accepteur de proton (p[K.sub.a] = 14,0). A l'oppose, l'atorvastatine (p[K.sub.a] = 4,5), un accepteur de proton beaucoup plus faible, est particulierement sensible aux effets de matrice. Pour les composes analyses en mode d'ion negatif, on a trouve que l'alcalinite de l'echantillon est importante. Avec un p[K.sub.a] de 10,4, le 17α-ethinylestradiol presente generalement un renforcement de matrice avec une augmentation de l'alcalinite de l'echantillon. Toutefois, la presence de coeluants acides contribue a la suppression de l'effet de matrice. Enfin, le <> est particulierement sensible a la suppression de la matrice du au fait que son p[K.sub.a] pratiquement neutre (7,9) provoque des changements considerables dans l'ionisation meme pour de faibles changements dans le pH des echantillons. On en conclut que meme si les diverses matrices ont une influence certaine sur l'ionisation de ces PPSP, les effets de matrice peuvent etre quantifies et surmontes. Mots-cles : produits pharmaceutiques et de soins personnels, effets de matrice, CL-SM/SM, sediments, biote. [Traduit par la Redaction], Introduction Environmental contamination of aquatic systems by pharmaceuticals and personal care products (PPCPs) has been of increasing concern in the last decade. However, limited availability of adequate analytical tools, mass [...]