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). It is intended to provide guidance to regulatory agencies that are currently developing their own NTA risk assessment guidelines for IRGM crops and to help harmonize regulatory requirements between different countries and different regions of the world

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). It is intended to provide guidance to regulatory agencies that are currently developing their own NTA risk assessment guidelines for IRGM crops and to help harmonize regulatory requirements between different countries and different regions of the world

Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case exposure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in laboratory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties contribute to the robustness of, and confidence in, environmental risk assessments for GE plants. Data from NTA studies, collected during the analysis phase of an environmental risk assessment, are critical to the outcome of the assessment and ultimately the decision taken by regulatory authorities on the release of a GE plant. Confidence in the results of early-tier laboratory studies is a precondition for the acceptance of data across regulatory jurisdictions and should encourage agencies to share useful information and thus avoid redundant testing

NOER of plant species where height and biomass could be assessed during the vegetative (21 DAA) and generative (BBCH 89) growth stage, respectively.

NOER of plant species where height and biomass could be assessed during the vegetative (21 DAA) and generative (BBCH 89) growth stage, respectively.</p

Feasibility of assessing vegetative and generative endpoints of crop- and non- crop terrestrial plant species for non-target terrestrial plant (NTTP) regulatory testing under greenhouse conditions - Fig 2

Mean plant height at the vegetative (21 DAA, (a)) and generative (BBCH 89, (b)) growth stage of the test plants, respectively. Error bars indicate the standard deviation and * indicate a statistical significant difference to the control (William`s test or Multiple Welch`s t-test with Bonferroni-Holm adjustment depending on homoscedasticity) for each plant species (α = 0.05, one sided). Missing columns within a treatment group indicates that no data could be assessed for the respective plant species.</p

Germination rate in % of harvested seeds (F1).

Germination rate in % of harvested seeds (F1).</p

Effect of Atlantis WG on plant height and biomass (expressed as ER₅₀ (with 95% confidence limits) recorded at 21 DAA (vegetative growth phase) and fully ripe stage of the plants BBCH 89 (generative growth phase) of the study.

Effect of Atlantis WG on plant height and biomass (expressed as ER50 (with 95% confidence limits) recorded at 21 DAA (vegetative growth phase) and fully ripe stage of the plants BBCH 89 (generative growth phase) of the study.</p