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Letter to the New Zealand Minister of Food and Fibre
The Honourable John Luxton
Minister of Food and Fibre
Parliament Buildings
Wellington
New Zealand
Dr Mae-wan Ho
England 18th May 1999
Your Excellency
I have recently learned that the New Zealand government is considering
registering genetically engineered bovine growth hormone (rBGH or BST) for
use in your diary industry.
I am writing to you as a scientist to urge you to consider the
precautionary principle very carefully before making any decision. The
precautionary principle clearly states that lack of full scientific
certainty should not be used as a reason for postponing measures to avoid
or minimize a threat.
Lack of Full Scientific Certainty Regarding BST
· As part of their 55,000 page application to the FDA in 1985,
Monsanto was required to submit a chart identifying every amino acid on
the 191 amino acid chain structure of BST. On that chart, amino acid 144
was represented as being lysine. However, a Monsanto scientist, Bernard
Violand later published evidence (Violand, B.N. et al (1994)
Journal of Protein Science. 3 (7) 1089-1097) that a mistake had resulted
in the production of BST and that instead of lysine at position 144, an
aberrent amino acid, epsilon-N-acetyllysine was being transcribed. One
amino acid difference in the middle of a chain can have serious
consequences. Monsanto has never officially admitted this error and the
FDA was unaware of it whilst the drug was under review.
· In the FDA paper (page 878, reference 47) Jerome Moore was cited
(Moore J.A. et al (1988) Endocrinology, 122, 2920) by writing "The
need to pursue more definitive studies has already been stated as
unnecessary because it has been determined that at least 90 percent of
(BST) is distroyed upon pasturization of milk." The FDA reviewers
have mis-cited Moore, he never researched pasteurization, his expertise is
in the feild of human growth hormone. They also cited Paul Groenewegen to
subtantiate that conclusion. However, Groenewegen pasteurised milk at 162
degrees fahrenheit for 30 mins, when 15 seconds was called for, and only
destroyed 19% of the BST. Again, a mis-quote from the scientific
literature by the FDA reviews.
· Had the FDA known about these mistakes they would have certainly
invalidated Monsanto’s $ 500 million worth of research and not
granted the licence application until further testing had been done.
Monsanto may have eliminated the abberent amino acid on their own but it
is not known whether this has been done nor whether their currently
marketed product POSILAC is an exact duplicate of naturally occuring BGH
or not . It has never been tested nor genuinely regulated by the U.S. FDA.
Milk and the Cancer Connection
·In 1995 researchers at the National Institutes of Health reported
that IGF-1 plays a central role in the progression of many childhood
cancers and in the growth of tumours in breast cancer, small cell lung
cancer, melanoma and cancers of the pancreas and prostate ( LeRoith,
Derek, et al. The role of insulin-like growth factor 1 receptor in
cancer. Annals New York Academy of Sciences, Vol. 766, Sept 7, 1995. pp
420-08). On January 23rd, 1998 researchers at the Harvard Medical School
released a major study providing conclusive evidence that IGF-1 is a
potent risk factor for prostate cancer (Chan, June M et al. Plasma
insulin-like growth factor 1 and prostate cancer risk: a prospective
study. Science, Vol. 279, Jan 23, 1998, pp 563-66). Other research
provides more evidence of IGF-1’s link to breast and colon cancer and
a strong link between cancer risk and a high level of IGF-1 is now
indisputable.
· All mammals produce IGF-1 molecules of similar structure and
human and bovine IGF-1 are completely identical. The question is why do
some people have high levels of IGF-1 while others do not? Is it all
genetically ordained or could there be other outside factors influencing
IGF-1 levels? In 1996 Dr. Samuel Epstein of the University of Illinois
clearly warned of the danger of high levels of IGF-1 contained in milk
from cows injected with synthetic bovine growth hormone (Epstein, Samuel
S. Unlabeled milk from cows treated with biosynthetic growth hormones: a
case of regulatory abdication. Internation Journal of Health Services, Vol
26, No1, 1996, pp 173-85).
· There is now genuine concern within the scientific community
about the safety of milk from BST - treated cows. Concerns that began as
early as 1988 in both England and the U.S. The main concern is the level
of IGF-1 found in milk from treated cows; estimates vary from twice as
high to 10 times higher than in normal cow’s milk (Mepham, T.B. et
al. Safety of milk from cows treated with bovine somatotrophin. The
Lancet, Vol. 344, July 16, 1994, pp 197-98). There is also concern that
the IGF-1 found in treated milk is much more potent that that found in
regular milk because it seems to be bound less firmly to its accompanying
proteins (see Epstein, Samuel, S.).
· Researchers at the FDA reported in 1990 that IGF-1 is not
destroyed by pasteurization and that pasteurization actually increases it
concentration in BST-milk. They also confirmed that undigested protein
could indeed cross the intestinal wall and cited tests which showed that
oral ingestion of IGF-1 produced a significant increase in the growth of a
group of male rats. It is not known whether IGF-1 in milk consumed by
humans is digested and broken down into its constitutive amino acids, as
no human studies have ever been conducted. Research done on a similar
hormone, Epidermal Growth Factor, has shown that this hormone is protected
against digestion in the human gut, when ingested in the presence of
casein which is a main component of milk (Playford, R.J., et al. Effects
of luminal grwoth factor preservation on intestinal growth. The Lancet,
Vol. 431, April 3 1993, pp 843-48).
· Thus there is a distinct possibility that IGF-1 in milk could
also avoid digestion and make its way into the intestine where it could
promote colon cancer. It is also conceivable that it could cross the
intestinal wall in sufficient amounts to increase the blood level of IGF-1
significantly and thereby increase the risk of breast and prostate
cancers.
There are too many serious questions surrounding the use of milk from
BST treated cows to allow its continued sale. In Europe we have maintained
a moratorium on the use of BST and products from BST-treated cows are not
sold in countries within the union. BST in banned in Austrilia and Japan
and Canada is also resisting pressure from the U.S. and the biotechnology
lobby to approve the use of BST commercially.
In light of the serious concerns about the safety of human consumption
of milk from BST-treated cows, I strongly suggest you exercise vigilance
and resist pressure to approve BST in New Zealand, so as to protect
yourselfves and others in the global market place against the very real
cancer risks posed by IGF-1.
Yours Faithfully
Dr Mae-Wan Ho
Open University
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