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This chapter introduces the specific biological and ecological elements of trees that need to be considered in the risk assessment of GM (genetically modified) trees, and the basics of environmental risk assessment. Trees have perennial growth habits with long lifespan, and many pathways for dispersal of propagules. Moreover, trees are often key species in ecosystems, they are present from temperate to tropical climates and have complex and multi-level interactions with other organisms. The possible environmental impacts of GM trees are discussed, and examples of scenarios where the GM trees may disperse and have environmental impacts are given. The chapter describes different environmental risk assessment frameworks. The basics of any risk assessment are hazard identification, estimation of potential consequences, estimation of the likelihood of these consequences to occur, estimation of the overall risk and deciding about risk management measures. Carrying out risk assessment usually includes a problem formulation step, definition of assessment endpoints from the broad protection goals and identification of those attributes that will be measured (measurement endpoints). As examples the EFSA guidance on risk assessment of GM plants and the Cartagena Biosafety Protocol guidance of GM trees are described. Moreover, both the comparative and per se risk assessment approaches are discussed.

The European Cooperation in Science and Technology (COST) Action FP0905 is aimed at evaluating the scientifi c knowledge of genetically modifi ed trees (GMT) related to biosafety protocols and coordinating existing and new information from various European countries. This will help to provide a basis for future EU policy and regulation recommendations regarding the use of GM forest trees. The COST Action FP0905 started the 12th of April 2010 and it will end the 11th of April 2014. Actually, 27 COST countries have signed the Memorandum of Understanding (MoU). Seven NON-COST countries are also involved in the Action. The main objective of the COST Action is to evaluate the scientific knowledge relevant for GMT biosafety protocols by putting together already existing information generated in various European and Non-EU countries as basis for future EU policy and regulation for the environmental impact assessment and the safe development and use of GMTs. To reach its objective, the Action work plan is organized in 4 Working Groups (WGs). [br/] WG1 has launched the building of a database that gather the current knowledge on fi eld trials and greenhouse experiments with transgenic trees. The expected outcome is to develop a clear factual overview of the status of GMTs in European and non-European countries. WG2 is launching and moving through expert-based surveys to: 1) evaluate the environmental impacts of GMTs, 2) assess the effi ciency of existing transgene containment strategies, and 3) investigate effective pre- and post-market monitoring techniques. WG3 is conducting two types of surveys to understand the kind of policies needed to meet the concerns of the society in relation to the use of GMTs. Through WG4 fi nally, accurate and science-based information is being communicated through a website including an open discussion forum to educate the general public on technical, socio-economic and environmental aspects of GM forest trees.

Transgenic biotechnology can assist forest tree improvement programs but it may also raise environmental safety concerns. The environmental effects of genetically modified transgenic trees (GMTs) have been studied in many countries during the last 15 years. Today there is an urgent need of putting together this scattered knowledge to build-up a European knowledge platform for addressing GMTs in plantations. The main aims of Working Group 2 (WG2) of the European Cooperation in Science and Technology (COST) Action FP0905 "Biosafety of transgenic forest trees" (http://www.cost-action-fp0905.eu/) are (1) to discuss, based on scientific facts, whether current containment strategies are appropriate or need to be improved for GMTs, (2) to define a common protocol to track the transgene from the laboratory to the final product, and (3) to assess the possible impacts of GMTs on the environment. The potential risks of GMTs, the fate of recombinant material and the potential relevance of recombinant genes on plant´s omics are other main aspects to be considered and compared to similar processes with endogenous genes in conventional breeding. The group involves experts from public research, government and independent regulatory sectors across COST and non-COST member countries. The activities of this group have been organized into three Task Groups focusing on (1) risk assessment studies and guidance documents, (2) the monitoring of the transgenes and recombinant plant material, and (3) the impact of GMTs on exposed ecosystems. As a first step of WG2 activity, a database of guidance documents from national and transnational sources dealing with impacts and risk assessments of GMTs is being created to identify common and case-specific issues on biosafety. It is expected that the information gained will facilitate (1) a science-based understanding of the impacts of GMTs on the environment in comparison with that of traditionally tree breeding, and (2) future socio-economic and cost/benefits analyses of GMTs in plantations.

The fate of five herbicides (glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron) was studied in two Finnish sugar beet fields for 26 months. Soil types were sandy loam and clay. Two different herbicide-tolerant sugar beet cultivars and three different herbicide application schedules were used. Meteorological data were collected throughout the study and soil properties were thoroughly analysed. An extensive data set of herbicide residue concentrations in soil was collected. Five different soil depths were sampled. The study was carried out using common Finnish agricultural practices and represents typical sugar beet cultivation conditions in Finland. The overall observed order of persistence was ethofumesate > glyphosate > phenmedipham > metamitron > glufosinate-ammonium. Only ethofumesate and glyphosate persisted until the subsequent spring. Seasonal variation in herbicide dissipation was very high and dissipation ceased almost completely during winter. During the 2 year experiment no indication of potential groundwater pollution risk was obtained, but herbicides may cause surface water pollution.

The construction of a mammalian cell expression vector using human cytomegalovirus immediate early gene enhancer to initiate transcription of inserted coding sequences is described. The vector also carries Epstein-Barr virus EBNA-1 nuclear antigen gene, ori-P sequences and hygromycin B resistance gene hph from E. coli. The expression capacity of this construct was tested by inserting the chloramphenicol acetyltransferase (CAT) gene into the vector. The EBV-CAT construct was transfected into various cell lines and high levels of CAT activity were obtained in human and monkey cells. In these cells, the vector DNA also replicates as an extrachromosomal element having 1 to 20 copies per cell. In most cases, the vector copy number and the expression level of inserted gene was in positive correlation in different cell clones.

A bovine papillomavirus expression vector carrying a neomycin resistance gene was transfected into different cultured mammalian cells (HeLa, MDCK, L6J1, NIH 3T3, C127, BHK) by the calcium phosphate precipitation method. Analysis of the state of DNA from G 418 resistant cell clones revealed that in only four (one C127 and three NIH 3T3 clones) out of 36 cell clones was the vector DNA detected as a monomeric episome. In most cases the BPV vector DNA was associated with host cell chromosomes. The vector DNA comigrated with the high molecular weight DNA fraction in agarose gels with typical integration fragments after restriction enzyme digestions. The copy numbers and integrity of the vector DNA in the cell clones were estimated by using BPV, neo Γ and pBR322 specific probes in separate quantitative hybridizations. In 25 clones clear indicators of deletions and/or rearrangements were observed. Deletions were localized in BPV and in pBR322 domains of the vector without a significant preference. The copy numbers were high in C127 clones (4–150 copies per cell), in two MDCK clones (> 100 copies per cell) and in the BHK clone (37 copies per cell). Other cell clones had five or less copies per cell. The amplified vector sequences were apparently integrated in a single chromosomal location in all except two MDCK cell clones, which had multiple integration sites.

Farmland biodiversity is an important characteristic when assessing sustainability of agricultural practices and is of major international concern. Scientific data indicate that agricultural intensification and pesticide use are among the main drivers of biodiversity loss. The analysed data and experiences do not support statements that herbicide-resistant crops provide consistently better yields than conventional crops or reduce herbicide amounts. They rather show that the adoption of herbicide-resistant crops impacts agronomy, agricultural practice, and weed management and contributes to biodiversity loss in several ways: (i) many studies show that glyphosate-based herbicides, which were commonly regarded as less harmful, are toxic to a range of aquatic organisms and adversely affect the soil and intestinal microflora and plant disease resistance; the increased use of 2,4-D or dicamba, linked to new herbicide-resistant crops, causes special concerns. (ii) The adoption of herbicide-resistant crops has reduced crop rotation and favoured weed management that is solely based on the use of herbicides. (iii) Continuous herbicide resistance cropping and the intensive use of glyphosate over the last 20 years have led to the appearance of at least 34 glyphosate-resistant weed species worldwide. Although recommended for many years, farmers did not counter resistance development in weeds by integrated weed management, but continued to rely on herbicides as sole measure. Despite occurrence of widespread resistance in weeds to other herbicides, industry rather develops transgenic crops with additional herbicide resistance genes. (iv) Agricultural management based on broad-spectrum herbicides as in herbicide-resistant crops further decreases diversity and abundance of wild plants and impacts arthropod fauna and other farmland animals. Taken together, adverse impacts of herbicide-resistant crops on biodiversity, when widely adopted, should be expected and are indeed very hard to avoid. For that reason, and in order to comply with international agreements to protect and enhance biodiversity, agriculture needs to focus on practices that are more environmentally friendly, including an overall reduction in pesticide use. (Pesticides are used for agricultural as well non-agricultural purposes. Most commonly they are used as plant protection products and regarded as a synonym for it and so also in this text.) Electronic supplementary material The online version of this article (doi:10.1186/s12302-016-0100-y) contains supplementary material, which is available to authorized users.