Can -omics inform a food safety assessment?

Omic technologies can in principle allow visualization of the all of changes that take place when the genetics, nutrition or environment of an organism is altered. Targeted compositional analysis is today a key component of the food safety assessment paradigm in which known nutrients, anti-nutrients, toxicants, allergens, and other molecules of potential biological importance to humans or animals are quantitatively analyzed. This allows safety assessors to compare the composition and safety of one food with closely related counterparts. Omic technologies measure many analytes-some of which are unidentified-but the analysis often sacrifices one or more of the characteristics of validated analytical methods currently used for food analysis. Databases that would allow the safety assessor to interpret differences are not currently available. There is also no reason to believe that the targeted compositional analysis in use today does not provide the evidence needed to ensure food safety, nor is there any current reason to believe that omics can add value to the safety assessment process. The regulation of transgenic crops is far more rigorous than is justified since they present no new risks compared with traditional breeding, and are more precisely defined and better understood than their non-transgenic equivalent.

Purification and characterization of a thermostable alpha-galactosidase from Thermoanaerobacterium polysaccharolyticum.

Food ingredients containing alpha-1,6-galactoside bonds elicit gastrointestinal disturbances in monogastric animals, including humans. Pretreatment of such ingredients with alpha-galactosidase (EC 3.2.1.22) has the potential to alleviate this condition. For this purpose, a thermostable alpha-galactosidase from Thermoanaerobacterium polysaccharolyticum was purified by a combination of anion exchange and size exclusion chromatographies. The enzyme has a monomeric molecular weight of approximately 80 kDa; however, it is active as a dimer. The optimum temperature for enzyme activity is 77.5 degrees C. Approximately 84 and 88% of enzyme activity remained after 36.5 h of incubation at 70 and 65 degrees C, respectively. Optimum activity was observed at pH 8.0, with a broad range of activity from pH 5.0 to 9.0. Different transition metals had weak to strong inhibitory effects on enzyme activity. The K(m) and V(max) of the enzyme are 0.29-0.345 mM and 200-232 micromol/min/mg of protein, respectively. Importantly, enzyme activity was only slightly inhibited by 75-100 mM galactose, an end product of hydrolysis. Enzyme activity was specific for the alpha-1,6-galactosyl bond, and activity was demonstrated on melibiose and soy molasses.

Food safety risks and consumer health.

The major food safety risks are not eating a healthy diet, and failure to avoid foodborne illness. Over one billion people in the world suffer from food insecurity and malnutrition. Nutritionally enhanced transgenic crops such as Golden Rice are one potential strategy for reducing malnutrition in the world. Transgenic crops are subjected to a rigorous pre-market safety assessment. The safety of novel proteins and other products is established, and through compositional analysis and animal studies, the safety of any observed changes is evaluated. These studies provide evidence that the new product is as safe as, or safer than, comparable varieties. It must be asked, however, if this rigorous analysis is necessary, because unregulated crops produced by other breeding methods also undergo genetic changes and contain unintended effects. Golden Rice poses infinitesimally small, if any, risk to consumers whilst it has the potential to spare millions of lives each year. However, because it is a transgenic crop, it cannot be deployed without years of expensive pre-market safety review. Paradoxically, if Golden Rice had been produced by less precise conventional methods of breeding, it would already be in the hands of poor farmers. It is concluded that the hyper-precautionary regulatory process applied to transgenic crops works to the extreme disadvantage of the hungry and the poor.

Compositional assessment of transgenic crops: an idea whose time has passed.

Compositional studies comparing transgenic crops with non-transgenic crops are almost universally required by governmental regulatory bodies to support the safety assessment of new transgenic crops. Here we discuss the assumptions that led to this requirement and lay out the theoretical and empirical evidence suggesting that such studies are no more necessary for evaluating the safety of transgenic crops than they are for traditionally bred crops.

Food safety evaluation of crops produced through biotechnology.

Agricultural biotechnology has been widely adopted in agriculture but is also the focus of controversy. Questions have arisen regarding food and environmental safety. In the US, responsibility for ensuring agricultural and environmental safety is delegated to the USDA and EPA, respectively. The FDA has primary responsibility for food safety, with the exception that the EPA has responsibility for the safety of proteins in plants associated with insect defense mechanisms. The food safety assessment, whether performed by the FDA or the EPA, requires evaluation of the safety of 1) the newly added DNA, 2) the safety of the newly introduced gene product and 3) the overall safety of the balance of the food. A paradigm called "Substantial Equivalence" guides the assessment. The principal food safety issues for new varieties crops are 1) potential toxicity of the newly introduced protein(s), 2) potential changes in allergenicity, 3) changes in nutrient composition, 4) unintended effects giving rise to allergenicity or toxicity and 5) the safety of antibiotic resistance marker-encoded proteins included with the transgene. All of these must be taken in the context of the predicted range of dietary exposures. The evaluation seeks to establish that there is a "reasonable likelihood of safety" and that new varieties are as safe as or safer than crops produced by traditional methods. Indeed, after extensive safety testing and some five years of experience with such crops in the marketplace, there is not a single report that would lead an expert food scientist to question the safety of such transgenic crops now in use.

Food biotechnology: benefits and concerns.

Recent advances in agricultural biotechnology have highlighted the need for experimental evidence and sound scientific judgment to assess the benefits and risks to society. Nutrition scientists and other animal biologists need a balanced understanding of the issues to participate in this assessment. To date most modifications to crop plants have benefited producers. Crops have been engineered to decrease pesticide and herbicide usage, protect against stressors, enhance yields and extend shelf life. Beyond the environmental benefits of decreased pesticide and herbicide application, consumers stand to benefit by development of food crops with increased nutritional value, medicinal properties, enhanced taste and esthetic appeal. There remains concern that these benefits come with a cost to the environment or increased risk to the consumer. Most U.S. consumers are not aware of the extent that genetically modified foods have entered the marketplace. Consumer awareness of biotechnology seems to have increased over the last decade, yet most consumers remain confused over the science. Concern over the impact on the safety of the food supply remains low in the United States, but is substantially elevated in Europe. Before a genetically engineered crop is introduced into commerce it must pass regulatory scrutiny by as many as four different federal regulatory bodies to ensure a safe food supply and minimize the risk to the environment. Key areas for more research are evaluation of the nutritional benefits of new crops, further investigation of the environmental impact, and development of better techniques to identify and track genetically engineered products.