Use of species sensitivity distributions to characterize hazard for insecticidal traits.

Species sensitivity distributions (SSDs) have a long history of use within environmental risk assessment to help make informed decisions about the potential risks associated with a variety of environmental stressors. Current risk assessments for transgenic crops conveying insect protection incorporate bioassays conducted on both pest and non-pest insects. As technology developers commercialize new insecticidal traits, SSDs combine the results of these individual studies to construct what may be a better picture of potential environmental risks.

An experimental platform using human intestinal epithelial cell lines to differentiate between hazardous and non-hazardous proteins.

Human intestinal epithelial cell lines (T84, Caco-2, and HCT-8) grown on permeable Transwell™ filters serve as models of the gastrointestinal barrier. In this study, this in vitro model system was evaluated for effectiveness at distinguishing between hazardous and non-hazardous proteins. Indicators of cytotoxicity (LDH release, MTT conversion), monolayer barrier integrity ([(3)H]-inulin flux, horseradish peroxidase flux, trans-epithelial electrical resistance [TEER]), and inflammation (IL-8, IL-6 release) were monitored following exposure to hazardous or non-hazardous proteins.

Dynamic role and importance of surrogate species for assessing potential adverse environmental impacts of genetically engineered insect-resistant plants on non-target organisms.

Surrogate species have a long history of use in research and regulatory settings to understand the potentially harmful effects of toxic substances including pesticides. More recently, surrogate species have been used to evaluate the potential effects of proteins contained in genetically engineered insect resistant (GEIR) crops. Species commonly used in GEIR crop testing include beneficial organisms such as honeybees, arthropod predators, and parasitoids.

Experiences in Engaging the Public on Biotechnology Advances and Regulation.

Public input is often sought as part of the biosafety decision-making process. Information and communication about the advances in biotechnology are part of the first step to engagement. This step often relies on the developers and introducers of the particular innovation, for example, an industry-funded website has hosted various authorities to respond to questions from the public.

Emerging Agricultural Biotechnologies for Sustainable Agriculture and Food Security.

As global populations continue to increase, agricultural productivity will be challenged to keep pace without overtaxing important environmental resources. A dynamic and integrated approach will be required to solve global food insecurity and position agriculture on a trajectory toward sustainability. Genetically modified (GM) crops enhanced through modern biotechnology represent an important set of tools that can promote sustainable agriculture and improve food security.

Building Better Environmental Risk Assessments.

Risk assessment is a reasoned, structured approach to address uncertainty based on scientific and technical evidence. It forms the foundation for regulatory decision-making, which is bound by legislative and policy requirements, as well as the need for making timely decisions using available resources. In order to be most useful, environmental risk assessments (ERAs) for genetically modified (GM) crops should provide consistent, reliable, and transparent results across all types of GM crops, traits, and environments.

Transgenic maize event TC1507: Global status of food, feed, and environmental safety.

Maize (Zea mays) is a widely cultivated cereal that has been safely consumed by humans and animals for centuries. Transgenic or genetically engineered insect-resistant and herbicide-tolerant maize, are commercially grown on a broad scale. Event TC1507 (OECD unique identifier: DAS-Ø15Ø7-1) or the Herculex®(#) I trait, an insect-resistant and herbicide-tolerant maize expressing Cry1F and PAT proteins, has been registered for commercial cultivation in the US since 2001.

Bringing policy relevance and scientific discipline to environmental risk assessment for genetically modified crops.

Although public opinion is important in deciding what is valued by society, governments have determined that scientific expertise is required to evaluate potential environmental effects of genetically modified (GM) crops. We suggest how to evaluate rigorously the environmental effects of GM crops in the context of a scientific investigation. Following a disciplined scientific approach to environmental risk assessment (ERA) for GM crops should help resolve controversy in identifying and addressing risk.

Assessing the ecological risks from the persistence and spread of feral populations of insect-resistant transgenic maize.

One source of potential harm from the cultivation of transgenic crops is their dispersal, persistence and spread in non-agricultural land. Ecological damage may result from such spread if the abundance of valued species is reduced. The ability of a plant to spread in non-agricultural habitats is called its invasiveness potential.

Three-year field monitoring of Cry1F, event DAS-01507-1, maize hybrids for nontarget arthropod effects.

Field studies were conducted over a 3-yr period to investigate the potential effects of cultivating transgenic maize hybrids containing a Cry1F insect-resistant protein on nontarget arthropod abundance. The narrow spectrum of activity of Cry1F against a subset of lepidopteran pest species would not suggest broad-spectrum effects on nontarget arthropods. However, because of the insecticidal nature of Bt proteins, an alternate hypothesis is that some nontargets may be affected by exposure to the protein.

Assessment of risk of insect-resistant transgenic crops to nontarget arthropods.

An international initiative is developing a scientifically rigorous approach to evaluate the potential risks to nontarget arthropods (NTAs) posed by insect-resistant, genetically modified (IRGM) crops. It adapts the tiered approach to risk assessment that is used internationally within regulatory toxicology and environmental sciences. The approach focuses on the formulation and testing of clearly stated risk hypotheses, making maximum use of available data and using formal decision guidelines to progress between testing stages (or tiers).

Subchronic feeding study of DAS-59122-7 maize grain in Sprague-Dawley rats.

59122 is a transgenic maize line containing event DAS-59122-7 that expresses the corn rootworm (CRW) specific pesticidal Cry34Ab1 and Cry35Ab1 proteins from Bacillus thuringiensis (Bt) Berliner strain PS149B1 and the phosphinothricin-N-acetyltransferase (PAT) protein from Streptomyces viridochromogenes for tolerance to the herbicidal ingredient glufosinate-ammonium. For the current study, 59122 maize grain, non-transgenic near-isogenic maize grain (091), and a commercially available non-transgenic reference maize grain (33R77) were grown under conditions simulating commercial farming practices. Adult Sprague-Dawley rats (12/sex/group) were fed diets formulated with 35% maize grain from either 59122, 091, or 33R77, or one of two separate lots of commercially available rodent chow prepared with commercially available corn (35%) in accordance with the standards of Purina Mills Labdiet 5002 for approximately 90 days.

A tiered system for assessing the risk of genetically modified plants to non-target organisms.

Representatives of the developers of modern agricultural biotechnology are proposing a tiered approach for conducting non-target organism risk assessment for genetically modified (GM) plants in Europe. The approach was developed by the Technical Advisory Group of the EuropaBio Plant Biotechnology Unit (http://www.europabio.

Thirteen week feeding study with transgenic maize grain containing event DAS-Ø15Ø7-1 in Sprague-Dawley rats.

Maize line 1507, containing event DAS-Ø15Ø7-1 (1507), is a genetically modified (GM) maize plant that expresses the cry1F gene from Bacillus thuringiensis (Bt) sbsp. aizawai and the phosphinothricin-N-acetyltransferase (pat) gene from Streptomyces viridochromogenes throughout the plant including in the grain expression of the Cry1F protein confers in planta resistance to the European corn borer (ECB; Ostrinia nubilalis Hübner: Crambidae) and other lepidopteran pests. Expression of the PAT protein confers tolerance to the herbicidal active ingredient glufosinate-ammonium.