Environmental risk assessment in agro-ecosystems: Revisiting the concept of receiving environment after the EFSA guidance document.

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 com-mercial 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-ecosystem

Biosafety of bee pollinators in genetically modified agro-ecosystems : current approach and further development in the EU

Bee pollinators are an important guild delivering a fundamental input to European agriculture due to the ecological service they provide to crops in addition to the direct economic revenues from apiculture. Bee populations are declining in Europe as a result of the effects of several environmental stressors, both natural and of anthropic origin. Efforts are ongoing in the European Union (EU) to improve monitoring and management of pollinator populations to arrest further declines. Genetically modified (GM) crops are currently cultivated in a limited area in Europe, and an environmental risk assessment (ERA) is required prior to their authorization for cultivation. The possible impacts of GM crops on pollinators are deemed relevant for the ERA. Existing ecotoxicological studies indicate that traits currently expressed in insect-resistant GM plants are unlikely to represent a risk for pollinators. However, new mechanisms of insect resistance are being introduced into GM plants, including novel combinations of Cry toxins and double strand RNA (dsRNA), and an ERA is required to consider lethal and sublethal effects of these new products on nontarget species, including insect pollinators. The evaluation of indirect effects linked to the changes in management practices (e.g. for herbicide-tolerant GM crops) is an important component of EU regulations and a requirement for ERA. This paper reviews current approaches used to test the sensitivity of pollinators to GM plants and their products to determine whether sufficient data are being provided on novel GM plants to satisfy EU risk assessment requirements

Transgenic Insecticidal Crops and Natural Enemies: A Detailed Review of Laboratory Studies

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

Cry Toxins and Proteinase Inhibitors in Transgenic Plants do have Non-Zero Effects on Natural Enemies in the Laboratory: Rebuttal to Shelton et al. 2009

A main point of our recent paper (Lovei et al. 2009) is that there are non-neutral effects of Cry toxins and proteinase inhibitors (PIs) on natural enemies in the laboratory and that the pattern of responses is complex and needs additional analysis. Shelton et al. (2009) aggressively attacked this conclusion. They claimed that all negative effects of Cry toxins are caused by effects of sublethally affected hosts and prey. We suggested in Lovei et al. (2009) and reiterate here that the actual situation is not that simple when laboratory studies are considered. We made our point by using statistical meta-analysis to show that there are more nonzero effects of Cry toxins and PIs on natural enemies than expected under a statistical null hypothesis that all observed effects were zero. The interested reader may want to examine the longer history of some of these issues (Lovei and Arpaia 2005; Andow et al. 2006; Romeis et al. 2006a,b). In our rebuttal, we first address the deeper, fundamental questions raised by Shelton et al. (2009) about the value of meta-analysis and then proceed to rebut the core criticisms about our statistical methods. Although Shelton et al. (2009) raised many other issues, we limited our rebuttal to these central issues; our lack of comment does not imply agreement with their other complaints. Shelton et al. (2009) make two criticisms of our work that are, in actuality, more fundamental criticisms of meta-analysis. These criticisms are made, in part, to defend the methods used and conclusions reached in reviews by O'Callaghan et al. (2005) and Romeis et al. (2006b), neither of which are based on meta-analyses. First they argued that nonsignificant P values are "devoid of futher meaning and interpretation" (Shelton et al. 2009, p. 318), and second, they

Composition of Arthropod Species Assemblages in Bt-expressing and Near Isogenic Eggplants in Experimental Fields

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 y

Adoption of Machine Learning Techniques to Enhance Classification Performance in Reactive Brain-Computer Interfaces

This paper proposes the adoption of an innovative algorithm to enhance the performance of highly wearable, reactive Brain-Computer Interfaces (BCIs), which exploit the Steady-State Visually Evoked Potential (SSVEP) paradigm. In particular, a combined time-domain/frequency-domain processing is performed in order to reduce the number of features of the brain signals acquired. Successively, these features are classified by means of an Artificial Neural Network (ANN) with a learnable activation function. In this way, the user intention can be translated into commands for external devices. The proposed algorithm was initially tested on a benchmark data set, composed by 35 subjects and 40 simultaneous flickering stimuli, obtaining performance comparable with the state of the art. Successively, the algorithm was also applied to a data set realized with highly wearable BCI equipment. In particular, (i) Augmented Reality (AR) smart glasses were used to generate the flickering stimuli necessary to the SSVEPs elicitation, and (ii) a single-channel EEG acquisition was conducted for each volunteer. The obtained results showed that the proposed strategy provides a significant enhancement in SSVEPs classification with respect to other state-of-the-art algorithms. This can contribute to improve reliability and usability of brain computer interfaces, thus favoring the adoption of this technology also in daily-life applications

A stakeholder engagement approach for identifying future research directions in the evaluation of current and emerging applications of GMOs

The yield of several commodity crops is provided in large part by genetically modified crops in North and South America. However, reservations exist in Europe due to possible negative effects on human health or environment. This paper aims to analyse the current research priorities identified in EU countries and to engage European stakeholders into the formulation of future common research needs regarding the effects of the possible adoption of commercially available and forthcoming genetically modified organisms (GMOs) in the areas of socio-economics, human and animal health, and environment. Additionally, it aims to identify the requirements for sharing available research capacities and existing infrastructures. First a mapping exercise of existing research activities in Europe was performed. A questionnaire was developed on a web-based platform and submitted to national focal points to collect information from EU Member States. Information was collected from 320 research projects conducted in the last 10 years in Europe. To refine results of the surveys, twenty invited experts and stakeholders from the public funding agencies of different EU Member States participated in an international workshop. This paper reports the main findings of these activities.