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#382 - Some Dangers Of Hormones In Milk, 23-Mar-1994

Last month, the first genetically-engineered food product went on sale
in the U.S., after final approval by the Food and Drug Administration
(FDA). The product is a cow growth hormone (called recombinant bovine
growth hormone, or rBGH), intended for needle injection into milk cows
every two weeks to make them produce more milk. Norway, Sweden,
Denmark, the Netherlands, and the Canadian provinces of Alberta,
British Columbia, and Ontario have banned commercial use of synthetic
bovine growth hormones. (The rBGH hormone is sometimes called rBST,
recombinant bovine somatotropin.)

Bovine growth hormone (BGH) is a normal product of the pituitary gland
of cows. To make the synthetic product, rBGH, drug companies have
learned to snip out a fraction of cow DNA that codes for this hormone,
insert it into the DNA of E. COLI bacteria, grow the bacteria in vats,
and extract large quantities of rBGH from the vats. (A synthetic human
growth hormone has been manufactured by similar techniques for several

Introduction of the rBGH product last month was met by an uproar from
consumers who want the product banned until safety questions have been
resolved and who want milk labeled if it is produced from rBGH-treated
cows. Monsanto, the chemical company that has brought the first rBGH
product to market, vigorously opposes labeling.

FDA has sided with Monsanto in opposing labeling of milk produced by
drug-treated cows, and has gone one step further. FDA opposes labeling
of products that are free of rBGH. FDA has even threatened legal action
against milk suppliers and grocers who label their milk as free of the
rBGH drug.[2] FDA says there is "no significant difference" between
milk from rBGH-treated cows and milk from cows not treated, and thus a
label saying "rBGH-free" would imply a difference that did not exist,
and this would constitute false labeling.[3] Monsanto has filed two
lawsuits against milk processors who labeled their product as free of
rBGH and has mailed warnings to others who might be tempted to label
their milk as rBGH-free.[4] The FDA's position on labeling was
developed under the direction of Michael R. Taylor, a lawyer who joined
FDA in 1991 after almost a decade as a partner in the law firm that
Monsanto hired to gain FDA approval of rBGH and that last month brought
Monsanto's lawsuits against milk producers who labeled their products
rBGH-free. (See RHWN #381.)

Despite what FDA statements might lead consumers to think, Monsanto's
rBGH is not identical to a cow's natural growth hormone. The two
hormones have a different amino acid sequence. The Monsanto product is
the cow's natural hormone with an extra amino acid (methionine)

According to agricultural researchers at the University of California
at Davis, the FDA faced a similar situation once before, when the
agency evaluated synthetic human growth hormone (rHGH).[6] A
manufacturer of rHGH produced a product that differed from the natural
product (HGH) in the same way that Monsanto's rBGH differs from natural
BGH; that is to say, the rHGH had an additional methionine residue at
one end. The PHYSICIANS DESK REFERENCE, a standard medical reference
book on drugs, says that 30% of rHGH-treated patients developed
antibodies (in other words, had an allergic reaction) compared to only
2% of HGH-treated patients. By analogy, this seems to raise the
distinct possibility that some people will have an allergic reaction to
Monsanto's rBGH who might not have an allergic reaction to natural BGH.
FDA has steadfastly refused to evaluate the potential for human
allergic reactions to rBGH.

There is considerable evidence that rBGH appears in the milk of rBGH-
treated cows.[7] However, FDA has not developed, and has not required
Monsanto to develop, a measuring technique that can distinguish between
Monsanto's rBGH product and the cow's natural hormone. This appears to
be a violation of law by FDA. Section 512 of the 1968 Animal Drug
Amendments to the 1938 Federal Food, Drug and Cosmetic Act requires
manufacturers submitting new animal drug applications to provide "a
description of practical methods" for analysis and monitoring of drug
residues in food.[8] The American Medical Association pointed out in
1991 that it is possible to develop a measuring technique to
distinguish between the natural product BGH and the genetically-
engineered product rBGH.[9] For reasons that are known only to FDA, the
agency has not developed such a technique. Because FDA has not
developed the necessary analytic technique, the agency can continue to
say that rBGH is indistinguishable from BGH, implying falsely that the
two hormones are identical.

Although human health effects of milk from rBGH-treated cows are
uncertain, health effects on cows are better understood. Normally for
about 12 weeks after a cow calves, she produces milk at the expense of
her own tissues. She loses weight, she is infertile, and she is more
susceptible to diseases such as mastitis (inflammation of the udder).
Eventually her milk output diminishes, her food intake catches up, and
she begins to rebuild her body. By injecting rBGH, a farmer can
postpone for another 8 to 12 weeks the time when the cow begins
rebuilding her body. This means that the cow is stressed for another 8
to 12 weeks and is more susceptible to infection during that period.

The Monsanto rBGH product, sold under the trade name Posilac, comes
with an insert sheet containing information about the drug. The Posilac
insert sheet says, in part, "Cows injected with Posilac are at an
increased risk for clinical mastitis (visibly abnormal milk). The
number of cows affected with clinical mastitis and the number of cases
per cow may increase. In addition, the risk of subclinical mastitis
(milk not visibly abnormal) is increased. In some herds, use of Posilac
has been associated with increases in somatic cell counts."[11] Somatic
cell counts are another name for pus in milk. The insert sheet mentions
other health effects of rBGH on cows: "Use of Posilac has been
associated with increases in cystic ovaries and disorders of the uterus
during the treatment period." And: "Use of Posilac may result in
increased digestive disorders such as indigestion, bloat, and

There is abundant evidence that, when cows get mastitis, farmers give
them antibiotics. Mastitis (or the pus it puts into milk) is a major
cause of lost revenues to dairy farmers. According to the U.S. General
Accounting Office (GAO), FDA has approved use of 30 antibiotics on
dairy cows but an additional 50 antibiotics are suspected of being used
illegally on dairy cows. A 1988 Illinois survey found over 200
different animal drugs on dairy farms, 58% of them not approved for use
on dairy cows. Furthermore, the routine tests that FDA applies to milk
nationwide can only detect 4 types of antibiotics, so FDA is not in a
position to protect consumers from illegal use of antibiotics (which
are sold without prescription at farm supply stores). Antibiotic
residues in milk --which seem certain to increase with rBGH use --may
cause adverse allergic reactions in some consumers, and very likely
will contribute to development of strains of bacteria that are
resistant to antibiotics, thus reducing the effectiveness of antibiotic
medicinals against human and animal diseases.[12] [More next week.]

--Peter Montague


[1] Gail Feenstra, "Introduction," in William C. Liebhardt, THE DAIRY
TECHNOLOGIES (Davis, Cal.: University of California Sustainable
Agriculture Research and Education Program, 1993), pgs. 19-20.

[2] Keith Schneider, "F.D.A. Warns the Dairy Industry Not to Label Milk
Hormone-Free," NEW YORK TIMES February 8, 1994, pg. A1.

[3] Michael R. Taylor, "Interim Guidance on the Voluntary Labeling of
Milk and Milk Products From Cows That Have Not Been Treated With
Recombinant Bovine Somatotropin," FEDERAL REGISTER Vol. 59 No. 28 (Feb.
10, 1994), pgs. 6279-6280.

[4] "Statement on Misleading Promotion and Advertising Activities," an
anonymous statement on Monsanto letterhead dated March 4, 1994, faxed
to us by staff of Tom McDermott [(314) 694-3605] of Monsanto in St.
Louis, Mo.

[5] Judith C. Juskevich and C. Greg Guyer, "Bovine Growth Hormone:
Human Food Safety Evaluation." SCIENCE Vol. 249 (1990), pgs. 875-884.

[6] Gail Feenstra, cited above, pg. 27.

[7] This evidence is reviewed in Gail Feenstra, cited above, pgs. 20-

[8] FDA requirements are discussed in Samuel S. Epstein, "Potential
Public Health Hazards of Biosynthetic Milk Hormones," INTERNATIONAL
JOURNAL OF HEALTH SERVICES Vol. 20 No. 1 (1990), pgs. 73-84.

[9] Council on Scientific Affairs, American Medical Association,
"Biotechnology and the American Agricultural Industry," JOURNAL OF THE
AMERICAN MEDICAL ASSOCIATION Vol. 265 (March 20, 1991), pg. 1433 says,
"Therefore, an antibody-based detection assay could be devised to
determine the percentage of recombinant vs native bST present in the
milk from rbST-treated animals."

[10] Donella Meadows, "Out to Pasture," GREEN ALTERNATIVES,
February/March 1994, pg. 56. And Kathleen Byrnes, "Synthesis," in
California Sustainable Agriculture Research and Education Program,
1993), pgs. 319-349.

[11] We asked Monsanto for a copy of the Posilac insert sheet. Staff of
Tom McDermott [(314) 694-3605] in St. Louis, Mo., told us March 23 they
were not sure whether their division had a copy; they said they would
check and call us back, but we did not hear from them again before our
press deadline. We received a copy from the Pure Food Campaign [1130
17th Street, N.W., Suite 630, Washington, DC 20036; telephone (202)

[12] Michael K. Hansen, "Testimony before the Agriculture Committee of
the Canadian Parliament on Potential Animal and Human Health Effects of
rbGH Use by Michael K. Hansen, Ph.D.," dated March 9, 1994. Available
from: Consumer Policy Institute, Consumers Union, 101 Truman Ave.,
Yonkers, NY 10703-1057. Telephone (914) 378-2000.

[13] Marietta Sue Brady and others, "Resistance Development Potential
of Antibiotic/Antimicrobial Residue Levels Designated as 'Safe
Levels,'" JOURNAL OF FOOD PROTECTION Vol. 56 No. 3 (March 1993), pgs.

Descriptor terms: food safety; fda; genetic engineering; biotechnology;
bgh; hgh; dna; bacteria; milk; labeling; monsanto; lawsuits; rtk;
michael taylor; revolving door; amino acids; methionine; posilac; pus;
mastitis; antibiotics; resistance; diarrhea; allergies; allergic
reactions; antibodies; animal rights;