Download Environmental and biosafety issues in modern biotechnology: Dr

Environmental and Biosafety issues
in modern Biotechnology
Dr Veena Chhotray, IAS
Senior Fellow, TERI
6th February, 2006
BIOSAFETY
‘Biosafety’ means the need to
protect human and animal health
and environment from the possible
adverse effects of the products of
modern biotechnology
International Evolution
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Environmentalism emerged as a distinct
development in the last forty years.
 Emergence
of “pressure groups” in the sixties
 First Earth Day (1970)
 The United Nations Conference on the Human
Environment and Development (1972)
 The Brundtland Report: our Common Future
(1987)
 The Rio Earth Summit (1992)
 Convention on Biodiversity (CBD) [1992]
 Cartagena Protocol on Biosafety (CPB) [1993]
Convention of Biodiversity (CBD) [1992]
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Focus: conservation and sustainable use of
biodiversity
Recognized the potential of modern biotechnology
for human well being
Took cognizance that modern biotechnology
could have serious effects on environment and
health
Article 8(g) emphasized the need to regulate the
risks associated with the use of LMOS.
Article 19(3) set the stage for a legally binding
international instrument about biosafety.
The Cartagena Protocol on Biosafety (CPB)
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Entered into force on 29th December 1993
Focus on transboundary movement of the
LMOS.
Seeks to lay down an internationally acceptable
framework to provide for an adequate level of
protection against the possible adverse affects of
LMOS on biodiversity and human health.
Basic Premises of CPB
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“Advance Informed Agreement” between Parties
(AIA)
Decision on the basis of scientific risk
assessment
Precautionary Principle
How is Genetic Engineering (GE) different
from conventional breeding (CB)?
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Combining DNA in new combinations and
introducing it into a new organism are the GE
tools.
Main differences between CB and GE
 Ability
to move across sexual barriers
 Amount of change: a specific gene embodying a
particular trait or thousands of genes embodying
desirable and undesirable traits
 Occurrence of change in one or several generations.
Genetic engineering:Recombinant DNA technology
Is GE inherently unsafe?
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Two diametrically opposite trends of thought
US-Canada
 No new risks associated with GM crops
 New regulations not considered necessary
 Safety assessments
 ‘Product’ rather
than ‘process’ based
 In comparison and contrast to their ‘familiarity’ and
‘substantial’ equivalence to conventional crops
…Is GE inherently unsafe?
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EU
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Safety assessment
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GE crops considered new and special
Existing legislation not considered sufficient
Process based
Principle of ‘substantial equivalence’ beginning rather than
the end
Adoption of ‘Precautionary Principle’ as guide
….Is GE inherently unsafe?
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GE technology carries certain inherent unpredictability
Some facts
 Isolation of a gene from its natural environment and
integration into entirely different organism
 Possible transgenic instability due to triggering of the
inbuilt defense mechanisms of the host organism
leading to inactivation or silencing of foreign genes.
….Is GE inherently unsafe?

Possibilities of integration of foreign gene at a site
predisposed to silencing of genes (position effect).
 Variance in the levels of expression of the
transgene in different environmental conditions
(heat, humidity, light…..)
 Possibilities of silencing of genes arising in
subsequent generations
Case by case sound scientific
assessment is of utmost significance
Biosafety issues in transgenic crops
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Relate to environmental, human and animal health
consequences
Both can have short and long term implications
Biosafety risks involve the entire spectrum of biodiversity
A universal ‘true for all’ approach may not be applicable
Risks
Known Probability
Unknown Probability
•Rigorous Scientific Assessment
•Risk Mitigation
•Precautionary Principle
..Biosafety issues in transgenic crops
Biosafety concerns arise from:
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Horizontal gene transfer
Genetic contamination
Transfer of allergens and toxins from one
life form to another and creation of new
toxins and allergenic compounds
..Biosafety issues in transgenic crops
-Main Concerns
 Development
of aggressive weeds/ wild relatives by
transfer of transgenic traits
 Erosion of land races/wild relatives by genetic
pollution in centres of origin/ diversity
 Harm to the non-target organisms
 Development of pest resistance by prolonged use
 Monoculture and limitations to farmers’ choice in
crop management
 Hazard to human and animal health by transfer of
toxins and allergens and by creation of new toxins
and allergenic compounds
..Biosafety issues in transgenic crops
Assessment
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GE venturing into an unknown biological
territory
ASILOMAR Conference (1975): No research till
safety guidelines in place
Initially, focus on laboratory safety procedures
Wider definition of biosafety with possibilities of
commercialization of GM products
The broad format of biosafety parametres
essentially the same in all regulations
..Biosafety issues in transgenic crops
Two main stages:
1.
2.
Laboratory/green house stage
Confined Trial Stage
IMPORTANT
Prevention of the spread of genetically
engineered material outside lab/field
Laboratory/green house stage
Different
biosafety levels as per the
degree of risk involved
Two methods of containment
Physical
Biological
Confined Trial Stage
A confined trial is a small scale release of a
transgenic plant species for research purposes
conducted under conditions that prevent spread
of the organism and mitigate its impact on the
surrounding environment
Objective is to collect data to evaluate the
crops’ performance
Focus on Risk Mitigation
Risk mitigation – the terms and conditions that are
necessary to conduct the trial safely.
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Prevent Gene Flow
Prevent entry of GMOs into food chain
Prevent Persistence of GMOs in the field
Bio-pharmaceutical therapeutics
Biosafety risk
 Survival, multiplication and dissemination of
GMOs in contained/ open environment
 Interaction of GMOs with biological systems
 Routes of dissemination: physical; biological
Risk depends upon
 Nature of organism invovled
 Extent of use of LMOs
 End product LMO or not?
…Bio-pharmaceutical therapeutics
Risk categorization of micro organisms:
determining factors
 Capability to cause disease
 Hazard to laboratory workers
 Risk of spread to community
 Availability of effective treatment
Health risks
 Toxigenicity
Pathogenicity
 Allergenicity
Antibiotic resistance
..Bio-pharmaceutical therapeutics
Environmental risks
 Outcrossing between GMOs and pathogens
 Negative effects on populations of non target
organisms
Risk assessment
 Access
 Expression
 Damage
Risk management and communication
 Physical
 Biological
GM foods: need for safety assessment
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Expressed proteins generally not a part of regular
food supply
Food complex mixtures e.g. nutrients, antinutrients and natural toxins
Directly enter human system
Assume different forms
Involve storage, processing, transportation
.. Safety assessment of GM foods comprise
Guidelines by Codex Alimentarius Commission
 Assessment of possible allergenicity
 Assessment of possible toxicity
 Compositional analysis of key components
 Food processing
 Nutritional modification
….GM foods: Allergenicity; Toxicity
Allergy
It is a hypersensitive reaction initiated by immunologic
mechanisms caused by specific substances called
allergens.
Assessment
 Is the gene source allergenic?
 Expression level of introduced gene
 Unintended effect
 Digestibility and heat stability
Toxicity
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New proteins as a result of intended modification
Unintended new proteins as a result of the modification
Natural constituents beyond their level of normal
variation
….GM foods: nutritional aspects;
unintended effects
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Intended and unintended changes in nutrient levels
Bioavailability of nutrients, stability and processing
Presence and effect of anti-nutrients
Impact of individual changes on overall nutritional profile
Unintended effects
Random integration of transgenes
 Insertional mutagenesis
 Disruption of gene functions
 Production of new proteins
 Changes in
o Phenotype
Metabolites
o Enzymes
Toxins
o Genotype
Concluding Note……
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Biosafety is integral to modern biotechnology
The adoption of modern biotech products
needs to be balanced with adequate biosafety
safeguards
Case by case scientific risk assessment and
cost benefit analysis
Greater acceptance of health care applications
Need based adoption in GM crops and foods
Participation of various stakeholders
Dissemination of knowledge and information
Thank you