Environmental and Biosafety issues in modern Biotechnology

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Oct 23, 2013 (3 years and 10 months ago)

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Environmental and Biosafety issues

in modern Biotechnology





Dr Veena Chhotray, IAS

Senior Fellow, TERI


6
th

February, 2006




‘Biosafety’ means the need to
protect human and animal health
and environment from the possible
adverse effects of the products of
modern biotechnology



BIOSAFETY



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]


International Evolution


Convention of Biodiversity (CBD) [1992]


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)


Entered into force on 29
th

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


“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)?


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


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?



EU


GE crops considered new and special


Existing legislation not considered sufficient


Safety assessment


Process based


Principle of ‘substantial equivalence’ beginning rather than
the end


Adoption of ‘Precautionary Principle’ as guide







…Is GE inherently unsafe?



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








….Is GE inherently unsafe?


Case by case sound scientific

assessment is of utmost significance


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

Biosafety issues in transgenic crops


Known Probability

Unknown Probability

Risks


Rigorous Scientific Assessment


Risk Mitigation


Precautionary Principle

Biosafety concerns arise from:



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


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.
Laboratory/green house stage

2.
Confined Trial Stage





IMPORTANT

Prevention of the spread of genetically

engineered material outside lab/field

..Biosafety issues in transgenic crops


Laboratory/green house stage



Different biosafety levels as per the
degree of risk involved


Two methods of containment


Physical


Biological

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

Confined Trial Stage






Risk mitigation


the terms and conditions that are
necessary to conduct the trial safely.



Prevent Gene Flow


Prevent entry of GMOs into food chain


Prevent Persistence of GMOs in the field

Focus on Risk Mitigation

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




Expressed proteins generally not a part of regular
food supply


Food complex mixtures e.g. nutrients, anti
-
nutrients and natural toxins


Directly enter human system


Assume different forms


Involve storage, processing, transportation


GM foods: need for safety assessment

Guidelines by Codex Alimentarius Commission


Assessment of possible allergenicity


Assessment of possible toxicity


Compositional analysis of key components


Food processing


Nutritional modification


.. Safety assessment of GM foods comprise

….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


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


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……


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