# Myths and Realities about Genetically Modified Food: A Risk-Benefit Analysis
## 3 Myths and Realities of GM Crops: Risk Assessment
### Environmental Safety Studies  
The main purpose of environmental risk assessments (ERA) is to determine whether a new GM crop variety has direct effects on the natural environment. These risk assessments aim to establish the effects that GE technology crops have on biodiversity in plant and animal communities, the diversity of crop species, and the potential effects on ecosystems and landscapes such as changes in soil and water qualities [8,48]. The international regulatory instrument known as the Cartagena Protocol on Biosafety (CPB) intends to protect biodiversity from the possible threats posed by GM crops. This protocol states that the precautionary principle should be applied to safeguard the environment. Nevertheless, no uniform ERA GM crop procedures have been devised, and every country's laws govern this situation [8]. Today, the ideal methodology followed to analyze the environmental risks posed by GM crops is the case-by-case assessment. The familiarity concept has also spread internationally in the GMO environmental safety context: becoming familiar implies acquiring enough information to facilitate risk and safety assessments. As familiarity is based on comprehending the ecosystem and its interactions with any introduced organisms, risk and safety assessments in one region might not be applicable to another [49]. Evidence for relating GM crops to adverse agronomic or environmental problems is scarce. Regarding agronomic aspects, the introduction of GM crops has not resulted in increased on-farm crop yields, except when insect-pest pressure is high. However, given the varying adoption rates of GM crops taken by farmers, as well as differences in land quality and financial resources, it has sometimes not been easy to determine the qualitative contribution of GM crop traits. Hence, it is important to enhance experimental approaches that disentangle the effects of GM traits from other factors [48]. The main concern of ERA is the gene flow (GF) of the transgene(s) to wild relatives [50]. The GF is the result of moving  
Figure 4: Cisgenic and transgenic modification. Icons made by [PERSON] and [PERSON] from www.flation.com (accessed on 1 December 2021). Adapted from [46]. gametes or individuals from a specific population to another, not only between populations of the same species but also between closely related species. This occurrence could lead to a marked change in the receiving population's allele frequency [8; 51]. This mobility may take place in natural plant populations by vegetative propagules, seeds, or pollen, and its relevance varies per plant species [52]. To gain insight into the rates and importance of hybridization, general ways of quantifying the GF utilize foreign herbicide and antibiotic resistance genes. Morphological and molecular markers are also needed to quickly help to identify or to identify/confirm hybrids [8]. The potential risk of the GF to produce cross-pollination between GM crops and wild species has been discussed. While producing commercial GM crops, a pollen-mediated GF has been reported in maize, cotton, soybean, and other species. The term \"co-existence\" was introduced to limit any undesired GF and to allow GM and non-GM crops to exist with mutual tolerance [53]. According to the 2003 Commission Recommendation definition, \"co-existence refers to the ability of farmers to make a practical choice between conventional, organic, and GM-crop production, in compliance with the legal obligations for labeling and/or purity standards\" [54]. This concept refers to consumers' right to choose among conventional, organic, and GM crops [53]. To make this right of choice possible, it is necessary not only to isolate the three supply chains but also to provide each one with the economic viability to survive. Co-existence can be defined as the minimum distance between GM and non-GM crop fields of the same species that should prevent the cross-pollination rate from reaching threshold levels [55].