1 Executive Summary
This review examines recent scientific evidence concerning potential environmental and
health risks of two GM maize lines – MON810 and T25. Following authorisation in the
European Union, Austria has invoked national safeguard measures according to Art. 16 of
Dir. 90/220/EEC for these GMOs. This analysis primarily focuses on the issues identified
by Austria as specific concerns in relation to these GM maize lines and considers the
Opinions of the European Commission’s Scientific Committees. In this summary the
environmental issues concerning the maize lines MON810 and T25 are addressed
separately, whereas the issue of health risks can be considered for both GM maize lines in
similar terms.
Environmental risks of MON810 maize
With regard to environmental risks of MON810 maize the following concerns are
specifically addressed:
• Possible unintended effects of the genetic modification on non-target organisms
• Uncertainties concerning the resistance management by a refuge strategy
• Likelihood of the development of secondary pests
• Lack of a monitoring plan
Considering unintended effects on non-target organisms (Chapter 4.1.1) only a very
limited number of non-target organisms were tested in the laboratory. Recent scientific
studies show that a wider range of insects, including non-target Lepidoptera, may be
adversely affected by MON810 maize. Additionally investigations of effects on non-target
organisms at higher trophic levels indicate that adverse effects of MON810 have to be
considered for a range of arthropod species, which were not included in previous risk
assessments.
A comprehensive assessment of these species in relation to the regional agricultural
conditions for commercial production has not been carried out. Based on current research
a large number of species occurs in agricultural areas and several of these species are
already classified as endangered. These species might be further threatened by the
cultivation of MON810.
Existing field trial data provided with the application are inappropriate to assess these
risks sufficiently because of methodological shortcomings, incompleteness of data and
poor statistical evaluation of results.
Concerning resistance management (Chapter 4.1.2) specific information necessary for
assessing the proposed management plan is missing. Baseline information about the pest
biology and ecology and a workable “Insect Resistance Management” plan must be
available before commercialisation of MON810 in an area with specific regional
characteristics. In particular basic data regarding resistance allele frequencies and
baseline susceptibilities were not gathered to date in Austria and are missing for an
assessment of the management measures. Due to the differences in climate and
agricultural practice, experiences gained from Bt maize cultivation in Spain cannot be
expected to be applicable to the Austrian agricultural system. These differences thus
indicate a need to adapt the insect resistance management strategies.
Another critical issue is the lack of a monitoring plan for cultivation of MON810
(Chapters 4.1.3 and 4.1.4). Firstly this conflicts with the current obligations for such
products. Annex VII of Directive 2001/18/EC can be considered as agreed minimum
standard for this issue. On the other hand, such a monitoring scheme would be necessary
to address the issue of secondary pests, a question considered important by the
Scientific Committee on Plants in their opinion on the safeguard measure for MON810
maize.
Environmental risks of T25 maize
With regard to environmental risks of T25 maize concerns specifically addressed in the
report are
• Risks for weed communities
• Lack of a monitoring plan
• Regional aspects in combination with coexistence issues
In summary the risk assessment data available for genetically modified herbicide tolerant
(GMHT) maize T25 do not fulfil the requirements for an assessment of how these new
herbicide/GM plant regimes could affect weed communities (see Chapter 4.2.1). As
changes in weed management are to be expected with introduction of T25 maize, a
proper assessment of the effects on weed communities is required, based on an indepth
analysis of weeds and interactions between the GMO and target organisms of
maize T25 as required both under Directive 90/220/EEC (Annex II, IV. C.3 and C.4) and
Directive 2001/18/EC (Annex IIIB, D.). The insufficient control of certain weeds provided
by glufosinate-ammonium and the resulting shift in weed communities has to be
considered adequately. The frequent use of a non-selective herbicide such as glufosinateammonium will increase the pressure on weeds thus resulting in the dominance of a few
species and finally the prevalence of resistant weed species. Recent records of experience
indicate that in such situations failures in weed control occur with GMHT plants. This
suggests that an increase or change in the proposed herbicide use and/or number of
applications has to be considered for maize T25. Furthermore, the cultivation of GMHT
maize T25 in combination with extensive use of a non-selective herbicide might further
contribute to the decline of already endangered plant species or biotope types.
Concerning the lack of a post-market monitoring plan (Chapter 4.2.2) the general
argument previously noted for MON810 also applies. Furthermore, long term effects of
the herbicide tolerant plant cannot be evaluated independently from the respective
herbicide use and effects of glufosinate-ammonium in combination with maize T25 on
weed communities need to be addressed by such a monitoring plan.
Additionally there are open questions concerning regional aspects in connection with
coexistence issues (Chapter 4.2.3). Harmonized, legally binding provisions regarding
coexistence measures (including liability) of genetically modified maize and conventional
or organic maize are still missing.
Potential health risks of the GM maize lines MON810 and T25
The review of the assessments of potential health risks of the GM maize lines
MON810 and T25 (Chapters 5.2 and 5.3 respectively) focuses on the assessment of
potential allergic or toxic properties as well as on the comparative analysis of plant
compounds (substantial equivalence). It considers the risk assessment approaches, the
methods chosen, the conduct of the experiments and the evidence presented. In both
cases of GM maize safety conclusions of the applicants cannot be fully verified because
detailed data are missing. More importantly, a number of shortcomings and weaknesses
of the risk assessments conducted by the applicants are revealed. This is particularly true
for GM-maize MON 810.
There are a number of similar shortcomings in both dossiers:
• By focusing on the introduced protein only the assessment of possible toxic
and allergenic properties does not take into account possible health risks of the
whole plant as a consequence of unintended effects of the genetic modification,
e.g. via upregulation of plant allergens. Furthermore, the possibility of new and
unexpected toxicants and allergens is not considered. The broiler feeding study
included in the MON810 dossier clearly is a feed conversion study and not a
toxicity study. The importance to better address unintended effects is
acknowledged by expert consultations including FAO/WHO and Codex
Alimentarius. Recently the European Commission stressed the importance of
Review of Austrian safeguard measures
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whole-food/plant studies for assessing both the potential toxic and allergenic
effects of the whole plant.
• Test proteins derived from bacterial sources are not necessarily representative of
the plant proteins in the field. A recent Australian study on GM peas revealed
immunogenic effects in mice that are most likely associated with differences in
posttranslational processing of the target protein between the donor and the host
organism.
• The assessments of allergenic properties rely on homology comparisons to
known allergens, in-vitro digestibility studies, a history of safe use (relevant for
both GM lines), low gene expression (relevant for maize line MON810) and the
absence of glycosylation (relevant for maize line T25). Recent scientific evidence
has however demonstrated that these methods do not constitute reliable
indicators of allergenic properties and can lead to either false positive or false
negative results.
• The risk assessments did not consider inhalation as a possible route of
exposure despite the fact that inhalation constitutes an important route for
sensitization.
• Furthermore, possible changes in the de-novo sensitizing properties were not
considered, neither of the introduced protein nor of the whole plant
• Toxicity endpoints were limited to acute oral (maize MON810) and 14-days
repeated-dose studies in rodents (T25), which do not provide any indications of
long-term effects
• Substantial equivalence claims are based on a limited range of compounds
analysed. The parameters chosen do neither meet the OECD nor industries own
consensus recommendations. In case of maize T25 compositional analysis of plant
material from European field trials was essentially limited to four plant
components. Statistically significant differences detected between the GM maize
lines and conventional counterparts are not properly considered
In summary, risk assessment data provided cannot – in the light of recent scientific
evidence - provide sufficient safety reassurance. In addition, the risk assessments
provided are highly unlikely to meet the requirements of Annex II of Directive
2001/18/EC, which constitutes the current standard for a reassessment of the safeguard
measures.
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