Zakiyya Parekh Student Number
Human Health and the Environment – Assignment #2
Name: Zakiyya Parekh Student Number: 998442546 Due Date: March 25, 2013 TA: Peter Quincy Ng
1 A.) i. EDI air = 1.50 g/kg*d
ii. EDI skin = 3.7253 x 10ˆ-5 g/kg*d
iii. The greatest exposure is through inhalation because the EDI for air is greater then the EDI for skin meaning there is a higher level of exposure to benzene through inhalation from the air then skin transfer.
B.) i. RMOS = 4.352
ii. An RMOS value less than one is considered an acceptable risk to exposure and an RMOS value greater than one is considered an unacceptable risk of exposure. With this being said, the RMOS value calculated from our EDI total and RsD is about 4.35 which is far greater than one. Thus this level of exposure to benzene is not an acceptable risk and the chemical exposure poses a potential health risk.
2.a.) There a number of concerns when it comes to the potential human health risks of genetically modified crops. Firstly, there has been an issue with the tendencies of these crops to provoke allergic reactions. The transfer of genes from commonly allergenic foods is discouraged unless it can be demonstrated that the protein product of the transferred gene is not allergic (World Health Organization (WHO), 2013). Thus GM foods must be tested for allergenicity by the Food and Agricultural Organization of the United Nations and WHO prior to being put on the market (WHO, 2013). Next, gene transfer from GM foods to cells of the body or to bacteria in the gastrointestinal tract would cause concern if the transferred genetic material affects human health (WHO, 2013). For example, this would be relevant if antibiotic resistance genes were to be transferred. If genes coded for antibiotic resistance entered the food chain and were taken up by the human gut microflora, the effectiveness of antibiotics could be reduced and human infectious disease risk increased (WHO, 2013). Another concern has to do with outcrossing, the movement of genes from GM plants into conventional crops or related species in the wild which may have an indirect effect on food safety and food security (WHO, 2013). An example of this was when traces of maize type which was approved for feed use was also found in maize products for human consumption in the US (WHO, 2013). Also, concern has been expressed about the potential for pleiotropic and insertional mutagenic effects. Insertional effects are silencing of genes, changes in levels of expression or the turning on of existing genes that were not normally expressed due to a random insertion (Malarkey, 2003, p.220). Pleiotropic effects are unexpected new metabolic reactions arising from activity of the inserted gene on existing substrates or changes in flow rates through normal metabolic pathways (Malarkey, 2003, p.220). Lastly, there is a potential for intrinsic toxicity of transgene products. A protein has the potential to exert health effects if it is not digested or absorbed systematically (Malarkey, 2003, p.218). As a result, protein toxins are known to act on acute mechanisms at low doses (Malarkey, 2003, p.218). b.) Genetically modified crops have proven to be beneficial in several ways. Firstly, crop losses from insect pests can be staggering and result in farmers having to use tons of chemical pesticides annually (Government of Victoria,2013). Consumers do not wish to eat foods that have been treated with pesticides because of potential health risks and as a solution GM crops can eliminate the application of pesticides and reduce the cost of bringing a crop to market (Government of Victoria, 2013). Secondly, farmers also spray quantities of different herbicides to destroy weeds which requires care so that the herbicide does not harm the crop plant or the environment (Government of Victoria,2013). GM crops can be engineered to be resistant to herbicides and reduce the herbicides needed (Government of Victoria, 2013). As well, there are many types of viruses, fungi and bacteria that cause plant diseases (Peterson et al., 2000, p.13). GM crops provides means of creating plants with geneticallyengineered resistance to these diseases (Peterson et al., 2000, p.13). Furthermore, malnutrition is common in third world countries where impoverished peoples rely on single crop for the main staple of diet (Peterson et al., 2000, p.13). For example, in certain countries rice does not provide the necessary nutrients to prevent malnutrition but this rice can be genetically engineered to contain additional vitamins and minerals and nutrient deficiencies will be alleviated (Peterson et al., 2000, p.13). Lastly, medicines and vaccines are often costly and require special storage conditions that are not available in third wold countries (Peterson et al., 2000, p.13). Researchers are developing edible vaccines in tomatoes and potatoes that are easier to ship, store and administer as opposed to injectable vaccines (Peterson et al., 2000, p.13). c.) I disagree with this statement. Although genetically-modified crops provide means of chemical pesticide and pests resistance aswell as lessen world hunger, the cost of the risk involved outweigh the benefits. GM crops pose risks to human health in a number of different ways: provoking allergenic reactions, impairing the effectiveness of antibiotic resistance, outcrossing hazards, insertional and pleiotropic effects that can cause carcinogens, protein
toxicity and the list goes on. There is no need for an agricultural biotechnology that may promise to solve world hunger if it’s only going to do the opposite by being detrimental to human health or ultimately causing human mortality. References
Malarkey, T. (2003). Human health Concerns with GM crops. Mutation Research, 544(2): 217-221. Retrieved from http://resolver.scholarsportal.info.myaccess.library.utoronto.ca/resolve/13835742/v544i23/217_hhcwgc
Peterson, G., S. Cunningham, L. Deutsch, J. Erickson, A. Quinlan, E. Raez-Luna, R. Tinch, M. Troell, P. Woodbury, and S. Zens. (2000). The risks and benefits of genetically modified crops: a multidisciplinary perspective. Conservation Ecology, 4(1): 13. Retrieved from http://www.consecol.org/vol4/iss1/art13/
State Government of Victoria. (2013). Genetically Modified Foods. Better Health Channel. Retrieved from http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/hl_foodnutrition?open&cat=Food_and_nutr ition_-_Food_processing
World Health Organization. (2013). 20 Questions on Genetically Modified Foods. Food Safety. Retrieved from http://www.who.int/foodsafety/publications/biotech/20questions/en/
Name: Zakiyya Parekh Student Number: 998442546 Due Date: March 25, 2013 TA: Peter Quincy Ng
1 A.) i. EDI air = 1.50 g/kg*d
ii. EDI skin = 3.7253 x 10ˆ-5 g/kg*d
iii. The greatest exposure is through inhalation because the EDI for air is greater then the EDI for skin meaning there is a higher level of exposure to benzene through inhalation from the air then skin transfer.
B.) i. RMOS = 4.352
ii. An RMOS value less than one is considered an acceptable risk to exposure and an RMOS value greater than one is considered an unacceptable risk of exposure. With this being said, the RMOS value calculated from our EDI total and RsD is about 4.35 which is far greater than one. Thus this level of exposure to benzene is not an acceptable risk and the chemical exposure poses a potential health risk.
2.a.) There a number of concerns when it comes to the potential human health risks of genetically modified crops. Firstly, there has been an issue with the tendencies of these crops to provoke allergic reactions. The transfer of genes from commonly allergenic foods is discouraged unless it can be demonstrated that the protein product of the transferred gene is not allergic (World Health Organization (WHO), 2013). Thus GM foods must be tested for allergenicity by the Food and Agricultural Organization of the United Nations and WHO prior to being put on the market (WHO, 2013). Next, gene transfer from GM foods to cells of the body or to bacteria in the gastrointestinal tract would cause concern if the transferred genetic material affects human health (WHO, 2013). For example, this would be relevant if antibiotic resistance genes were to be transferred. If genes coded for antibiotic resistance entered the food chain and were taken up by the human gut microflora, the effectiveness of antibiotics could be reduced and human infectious disease risk increased (WHO, 2013). Another concern has to do with outcrossing, the movement of genes from GM plants into conventional crops or related species in the wild which may have an indirect effect on food safety and food security (WHO, 2013). An example of this was when traces of maize type which was approved for feed use was also found in maize products for human consumption in the US (WHO, 2013). Also, concern has been expressed about the potential for pleiotropic and insertional mutagenic effects. Insertional effects are silencing of genes, changes in levels of expression or the turning on of existing genes that were not normally expressed due to a random insertion (Malarkey, 2003, p.220). Pleiotropic effects are unexpected new metabolic reactions arising from activity of the inserted gene on existing substrates or changes in flow rates through normal metabolic pathways (Malarkey, 2003, p.220). Lastly, there is a potential for intrinsic toxicity of transgene products. A protein has the potential to exert health effects if it is not digested or absorbed systematically (Malarkey, 2003, p.218). As a result, protein toxins are known to act on acute mechanisms at low doses (Malarkey, 2003, p.218). b.) Genetically modified crops have proven to be beneficial in several ways. Firstly, crop losses from insect pests can be staggering and result in farmers having to use tons of chemical pesticides annually (Government of Victoria,2013). Consumers do not wish to eat foods that have been treated with pesticides because of potential health risks and as a solution GM crops can eliminate the application of pesticides and reduce the cost of bringing a crop to market (Government of Victoria, 2013). Secondly, farmers also spray quantities of different herbicides to destroy weeds which requires care so that the herbicide does not harm the crop plant or the environment (Government of Victoria,2013). GM crops can be engineered to be resistant to herbicides and reduce the herbicides needed (Government of Victoria, 2013). As well, there are many types of viruses, fungi and bacteria that cause plant diseases (Peterson et al., 2000, p.13). GM crops provides means of creating plants with geneticallyengineered resistance to these diseases (Peterson et al., 2000, p.13). Furthermore, malnutrition is common in third world countries where impoverished peoples rely on single crop for the main staple of diet (Peterson et al., 2000, p.13). For example, in certain countries rice does not provide the necessary nutrients to prevent malnutrition but this rice can be genetically engineered to contain additional vitamins and minerals and nutrient deficiencies will be alleviated (Peterson et al., 2000, p.13). Lastly, medicines and vaccines are often costly and require special storage conditions that are not available in third wold countries (Peterson et al., 2000, p.13). Researchers are developing edible vaccines in tomatoes and potatoes that are easier to ship, store and administer as opposed to injectable vaccines (Peterson et al., 2000, p.13). c.) I disagree with this statement. Although genetically-modified crops provide means of chemical pesticide and pests resistance aswell as lessen world hunger, the cost of the risk involved outweigh the benefits. GM crops pose risks to human health in a number of different ways: provoking allergenic reactions, impairing the effectiveness of antibiotic resistance, outcrossing hazards, insertional and pleiotropic effects that can cause carcinogens, protein
toxicity and the list goes on. There is no need for an agricultural biotechnology that may promise to solve world hunger if it’s only going to do the opposite by being detrimental to human health or ultimately causing human mortality. References
Malarkey, T. (2003). Human health Concerns with GM crops. Mutation Research, 544(2): 217-221. Retrieved from http://resolver.scholarsportal.info.myaccess.library.utoronto.ca/resolve/13835742/v544i23/217_hhcwgc
Peterson, G., S. Cunningham, L. Deutsch, J. Erickson, A. Quinlan, E. Raez-Luna, R. Tinch, M. Troell, P. Woodbury, and S. Zens. (2000). The risks and benefits of genetically modified crops: a multidisciplinary perspective. Conservation Ecology, 4(1): 13. Retrieved from http://www.consecol.org/vol4/iss1/art13/
State Government of Victoria. (2013). Genetically Modified Foods. Better Health Channel. Retrieved from http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/hl_foodnutrition?open&cat=Food_and_nutr ition_-_Food_processing
World Health Organization. (2013). 20 Questions on Genetically Modified Foods. Food Safety. Retrieved from http://www.who.int/foodsafety/publications/biotech/20questions/en/
