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The environmental risk assessment (ERA) for genetically modified plants (GMPs) is a prerequisite for commercial approval of these new varieties according to regulatory systems worldwide. The first country to regulate GM crops was the USA and the issue of possible environmental impacts was based on the principles used in risk assessment of pesticides. Two main pillars of this approach are the use of surrogate species for testing effects on non-target organisms using a tiered assessment with clear thresholds to indicate the need to move between tiers. The latest EFSA guidance document on ERA of Genetically Modified Organisms considers specifically the receiving environment in preparation of ERA for commercial cultivation of GMPs. According to existing guidelines in the EU, the receiving environment is defined by three mutually interacting components: the characteristics of the environmental stressor (i.e. the GM plant), the bio-geographical regions where the commercial release of the crop is expected and the agricultural systems therein. Difference in agronomic and ecological conditions (e.g. use of different varieties, vegetation of adjacent areas, non-target species assemblages, sensitivity of local species to the stressors) suggests that explicit considerations of the receiving environments are necessary. Results from field experiments indicate that differences in cultivation practices, e.g. the herbicide regime used on herbicide-tolerant GM crops, may induce direct and indirect effects on wild plant distribution and abundance, with consequent repercussions on food webs based on these plants. Moreover, ecological literature indicates that the concept of surrogate species has clear limitations if applied broadly to any ERA. Starting from case studies regarding GMPs, this paper discusses some ecological and agronomic characteristics of agro-ecosystems, which have implications in the elaboration of both hazard and exposure analyses during ERA. The species selection approach indicated in the EFSA Guidance Document and the consideration of the area(s) of the expected release of the new variety may provide the basis to an ecologically sound ERA for a range of environmental stressors. The quality of the data that become available for risk managers with this approach may support a more transparent and dependable ERA and risk management for GMPs as well as for other potential environmental stressors in agro-ecosystems., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontarget organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure of nontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepidoptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor (e.g., Cry1-expressing maize plants), we conducted a two-year field survey of butterflies and weeds. Indicator species were selected-Aglais (Inachis) io in the Northern site and Vanessa cardui in the Southern site-and their phenology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions: highest exposure is foreseen for A. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability., (© 2018 Institute of Zoology, Chinese Academy of Sciences.)

In legal frameworks worldwide, genetically modified plants (GMPs) are subjected to pre-market environmental risk assessment (ERA) with the aim of identifying potential effects on the environment. In the European Union, the EFSA Guidance Document introduces the rationale that GMPs, as well as their newly produced metabolites, represent the potential stressor to be evaluated during ERA. As a consequence, during several phases of ERA for cultivation purposes, it is considered necessary to use whole plants or plant parts in experimental protocols. The importance of in planta studies as a strategy to address impacts of GMPs on non-target organisms is demonstrated, to evaluate both effects due to the intended modification in plant phenotype (e.g. expression of Cry proteins) and effects due to unintended modifications in plant phenotype resulting from the transformation process (e.g. due to somaclonal variations or pleiotropic effects). In planta tests are also necessary for GMPs in which newly expressed metabolites cannot easily be studied in vitro. This paper reviews the scientific literature supporting the choice of in planta studies as a fundamental tool in ERA of GMPs in cultivation dossiers; the evidence indicates they can realistically mimic the ecological relationships occurring in their receiving environments and provide important insights into the biology and sustainable management of GMPs., (Copyright © 2017 Elsevier B.V. All rights reserved.)

By means of a literature survey, earthworm species of significant relevance for soil functions in different biogeographical regions of Europe (Atlantic, Boreal, Mediterranean) were identified. These focal earthworm species, defined here according to the EFSA Guidance Document on the environmental risk assessment (ERA) of genetically modified plants, are typical for arable soils under crop rotations with maize and/or potatoes within the three regions represented by Ireland, Sweden and Spain, respectively. Focal earthworm species were selected following a matrix of four steps: Identification of functional groups, categorization of non-target species, ranking species on ecological criteria, and final selection of focal species. They are recommended as appropriate non-target organisms to assess environmental risks of genetically modified (GM) crops; in this case maize and potatoes. In total, 44 literature sources on earthworms in arable cropping systems including maize or potato from Ireland, Sweden and Spain were collected, which present information on species diversity, individual density and specific relevance for soil functions. By means of condensed literature data, those species were identified which (i) play an important functional role in respective soil systems, (ii) are well adapted to the biogeographical regions, (iii) are expected to occur in high abundances under cultivation of maize or potato and (iv) fulfill the requirements for an ERA test system based on life-history traits. First, primary and secondary decomposers were identified as functional groups being exposed to the GM crops. In a second step, anecic and endogeic species were categorized as potential species. In step three, eight anecic and endogeic earthworm species belonging to the family Lumbricidae were ranked as relevant species: Aporrectodea caliginosa, Aporrectodea rosea, Aporrectodea longa, Allolobophora chlorotica, Lumbricus terrestris, Lumbricus friendi, Octodrilus complanatus and Octolasion cyaneum. Five out of these eight species are relevant for each biogeographical region with an overlap in the species. Finally, the earthworm species Ap. caliginosa (endogeic, secondary decomposer) and L. terrestris (anecic, primary decomposer) were selected as focal species. In the Mediterranean region L. terrestris may be substituted by the more relevant anecic species L. friendi. The selected focal species are recommended to be included in a standardized laboratory ERA test system based on life-history traits., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Genetically modified (GM) maize MON810 expresses a Cry1Ab insecticidal protein, derived from Bacillus thuringiensis (Bt), toxic to lepidopteran target pests such as Ostrinia nubilalis. An environmental risk to non-target Lepidoptera from this GM crop is exposure to harmful amounts of Bt-containing pollen deposited on host plants in or near MON810 fields. An 11-parameter mathematical model analysed exposure of larvae of three non-target species: the butterflies Inachis io (L.), Vanessa atalanta (L.) and moth Plutella xylostella (L.), in 11 representative maize cultivation regions in four European countries. A mortality-dose relationship was integrated with a dose-distance relationship to estimate mortality both within the maize MON810 crop and within the field margin at varying distances from the crop edge. Mortality estimates were adjusted to allow for physical effects; the lack of temporal coincidence between the susceptible larval stage concerned and the period over which maize MON810 pollen is shed; and seven further parameters concerned with maize agronomy and host-plant ecology. Sublethal effects were estimated and allowance made for aggregated pollen deposition. Estimated environmental impact was low: in all regions, the calculated mortality rate for worst-case scenarios was less than one individual in every 1572 for the butterflies and one in 392 for the moth.

This review uses a data-driven, quantitative method to summarize the published, peer-reviewed literature about the impact of genetically modified (GM) plants on arthropod natural enemies in laboratory experiments. The method is similar to meta-analysis, and, in contrast to a simple author-vote counting method used by several earlier reviews, gives an objective, data-driven summary of existing knowledge about these effects. Significantly more non-neutral responses were observed than expected at random in 75% of the comparisons of natural enemy groups and response classes. These observations indicate that Cry toxins and proteinase inhibitors often have non-neutral effects on natural enemies. This synthesis identifies a continued bias toward studies on a few predator species, especially the green lacewing, Chrysoperla carnea Stephens, which may be more sensitive to GM insecticidal plants (16.8% of the quantified parameter responses were significantly negative) than predators in general (10.9% significantly negative effects without C. carnea). Parasitoids were more susceptible than predators to the effects of both Cry toxins and proteinase inhibitors, with fewer positive effects (18.0%, significant and nonsignificant positive effects combined) than negative ones (66.1%, significant and nonsignificant negative effects combined). GM plants can have a positive effect on natural enemies (4.8% of responses were significantly positive), although significant negative (21.2%) effects were more common. Although there are data on 48 natural enemy species, the database is still far from adequate to predict the effect of a Bt toxin or proteinase inhibitor on natural enemies.

The environmental impact of genetically modified (GM) plants in experimental fields has been examined in several ways, in particular with respect to the dynamics of specific nontarget organisms. The approach of sampling for biodiversity in agroecosystems to compare complex patterns could also be useful in studying potential disruptions caused by GM crops. In this study, we set up replicated field plots of Bt-expressing eggplants and near isogenic untransformed eggplants as a control. We monitored the presence and abundance of herbivore and predator arthropods in weekly visual samplings of the plant canopy for three growing seasons (2001-2003). Insect species were pooled in organismal taxonomic units (OTUs); three multivariate methods were used to compare species assemblage as an estimate of insect biodiversity. This multistep statistical approach proved to be efficient in recognizing association patterns, as evidenced by the data for the target species Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) clearly showing a significant association with the control plots. All the analyses indicate a comparable species assemblage between transgenic and near isogenic eggplant areas. Our results suggest that some taxa may warrant more specific study. For example, Alticinae beetles (Coleoptera: Chrysomelidae) were alternatively more abundant in either of the two treatments, and their overall abundance was significantly higher on transgenic eggplants. In light of these results and because of their taxonomic proximity to the target species, these herbivores may represent an important nontarget group to be further studied. Moreover, some sap feeders (e.g., Homoptera: Cicadellidae) were more abundant on Bt-expressing plants in some samples in all 3 yr.