**6. Human health risk and safety assessment of genetically modified crops**

General people consider foods obtained from conventionally developed crops are safe and GM crops possess risks to human health and the environment. Previously risk assessment used to be carried out based on some common principles that were introduced in 1993 [20]. Later on, an international body called 'Ad Hoc Intergovernmental Task Force on Foods Derived from Biotechnology of the Codex Alimentarius Commission', jointly established by the Food and Agriculture Organization (FAO) and World Health Organization (WHO) and developed a guideline for help the national authorities to assess the human health risk of GM foods. The three main concerns for human health from GM foods are (i) allergenicity—the transgene should not be allergenic (currently no allergic effect was recorded), (ii) gene transfer—from GM food to the body cells or to the bacteria of gut microbiome; particularly concerning if antibiotic resistant genes are used. Therefore, any technique used in GM crop development that involves antibiotic resistant genes are

discouraged, and (iii) outcrossing—several cases have been reported where transgene from GM crops approved for animal feed or industrial purposes [21]. According to the Codex Alimentarius, the human health risk assessment of GM crops is based on the principle that a newly developed GM crop should be compared with the conventional counterpart with a history of safe use [22]. The whole idea is that the newly developed GM crop is not compositionally different than its conventional counterpart except the newly introduce gene product/s [23].

According to the studies of National Cancer Institute, from 1975 to 2011, some specific types of cancer incidence has increased and some other has decreased in the USA. No absolute pattern was observed in the incensement or reduction of cancer incidence. If GM foods were a factor to increase cancer incidence in human, then there supposed to be a substantial increase in cancer incidence from 1995 when USA introduced GM crops in the market [24]. Another study published data on cancer incidence worldwide from 1980 to 2010 on breast and cervical cancer. This report showed that the incidence of these 2 cancers has increased in a similar pattern in the USA, Canada, and Europe. Interestingly, GM crops are not generally consumed in the European Union [25]. Epidemiological data was examined in the USA to find out the correlation between GM foods and chronic kidney disease (CKD). The prevalence of all stages CKD in the USA has increased 2% between 1994 and 2004. After that the prevalence did not increase significantly. Therefore, this increase is not correlated with the consumption of GM foods [26]. Similarly, no relationship was found between obesity and type-II diabetes with the consumption of GM foods. Similar conclusion was also made for gastrointestinal tract diseases, celiac disease, and food allergy and autism. Spectrum disorder [27].

The consumption of genetically modified foods direct human health safety assessment is considered as it is safe or unsafe. Many organizations such as the U.S. Environmental Protection Agency (EPA), the U.S. Department of Agriculture (USDA), and the U.S. Food and Drug Administration (FDA) other agencies in other countries or by companies, nongovernmental organizations (NGOs), and academic institutions conducted several research for human health safety assessment. American Association for the Advancement of Science says crop improvement by the modern molecular techniques of biotechnology is safe [28]. Genetically modified foods currently available on the international market have passed safety assessments and are not likely to present risks for human health World Health Organization [21]. All the available GM crops in the market did not show any kind of major human health risks till now. Also, newly developed GM crops must go through proper risk and safety assessments for better acceptability. It suggests the necessity of labeling GM food so that consumers can make their own choice [29].
