Newsletter -SAFETY OF OUR FOODS AND LIFE-
1998, November, No.115
"Male sperm counts had dropped forty-five percent, from an average of 113 million per milliliter in 1940 to 66 million per million in 1990." Dr. Skakkebaek, a specialist in male reproduction and spermatogenesis and a chief of the Department of Growth and Reproduction at the University Hospital in Copenhagen, published this shocking report in 1992. Since then, this report has been used various books and magazines including "Our Stolen Future" and "Feminization of our nature."
The Citizens' Table on Endocrine Disruptors (CTED) invited Dr. Skakkebaek. Dr. Skakkebaek stayed in Japan for a week from October 9 th to give speeches organized by the CTED in Kyoto and in Fukuoka.
Although Dr. Skakkebaek has come to Japan for four times before, it was first time for him to give speech to Japanese general public. About 850 people in Kyoto and 2700 people in Fukuoka came to listen his speech.
<Infertility is a serious problem in Denmark>
Dr. Skakkebaek is a professor of University at Copenhagen, an advisor both to the Danish government and to the World Health Organization. He is working as a doctor at University Hospital, seeing patients with reproductive disorder, such as hermaphroditism (people who has both male and female characteristics), infertility, delayed puberty, and precocious puberty.
Infertility is a quite serious problem in Denmark. In 1997, 15 hospitals in Denmark carried out artificial reproductions for 1900 patients; IVF (In vitro fertilization) 1400 and ICSI (Intracytoplasmic Sperm Injection) 500. The rate of artificial reproduction in Denmark is 3.7%, which means 1 out of 25 children were born with artificial reproduction. Dr. Skakkebaek said that "Since many couples can not have a baby even with artificial reproduction, couples who could have babies are very lucky."
Why there are so many problems in reproductive systems? Are EDCs one of the causes? Various animal testing have already proved that bisphenol A (material of polycarbonate resin), dioxin, methoxychlor (pesticide), oxtylphenol (pesticide), and vinclozolin (fungicide) are endocrine disruptors which cause decreasing sperm counts. Are these chemicals affect not only testing animals but also humans?
In 1993, Dr. Skakkebaek and Dr. Sharp (England) hypothesized that "When fetus is exposed with estrogenic substances, the incident rate of testicular cancer, hypospadias, undescended testis, and abnormal sperm become high."
<Scary Testicular Cancer>
In Denmark, the incident rate of testicular cancer is the highest in the world, and 10 people out of 100 thousand people get the disease. In Finland, neighbor country of Denmark, the incident rate is 2.8 people out of 100 thousand people and 2.2 in Japan. It is very surprising that people in Denmark has so high incident of testicular cancer. Also it is worth while to pay attention to the fact of increasing rate of testicular cancer all over the world.
Why it is important to pay attention to testicular cancer? Because testicular cancer can be one disease that clearly shows recent changes of male reproduction. Testicular cancer is increasing among youth who are going to have children soon, and testicular cancer is one cause of infertility.
Generally, the older we are, the higher the risk of getting cancer we have. However, in the case of testicular cancer, young people during the age from 25 to 45 have higher risk.
After a cancer tumor made in human, it takes about 20 years to develop into its pathological states. That is why we have higher risk when we become older. Since the peak of the testicular cancer is highest during the age from 25 to 45, Dr. Skakkebaek hypothesed that "testicular cancer may begin when people are very young, probably from when the baby is in her mother's womb."
< People get testicular cancer before born?>
A research in semen shows that the average sperm counts among testicular cancer patients is 7.5 million/cc. This is much lower than that of reference, 58 mill/cc. Since people who have less than 40 million/cc have difficulty in having children, most testicular cancer patients may suffer from infertility problem.
Dr. Skakkebaek found precursor cell to the testicular cancer in 1987. The precursor cells, called as Carcinoma in situ (CIS), look like primitive cells that you see in embryos. It is very unusual for adults to have this kind of primitive cell, however, patients of testicular cancer have the CIS. It suggested that something has happened at very early in life, probably in the womb, and at that time, the cells may become fixed prematurely at an early stage of development. That is why the patients have the premature cells.
<Hormone level is related to the development of testicular cancer>
Dr. Skakkebaek tried to find fact to show the relationship between testicular cancer and fetal life. He investigated the correlation between low birth weight and testicular cancer. As a result, the person who was born with low birth weight has 3 times higher risk, which means that environment during fetus life may relate to testicular cancer.
There is a period with high incident rate of testicular cancer other than the age from 25 to 40; soon after born. This can be explained by hormone level.
There are two periods with high hormone level in our life: one is, as you can imagine, puberty, and the other is the period soon after born. Since hormone level soon after born is very high, we can call this period as "mini-puberty."
During "mini-puberty," if fetus have CIS, hormone stimulates the development of cancer. That is why the incident rate of testicular cancer is high soon after born. Hormone level relates to testicular cancer.
<What is the real cause of male reproductive problems? Environment or Genetic?>
Dr. Skakkebaek says "the cause of various male reproductive problems is environment in a broad sense." The reproductive problems occur just this one / two generations. Since genetic change can not be happen that quick, this can not be explained.
"In conclusion, we should be concerned about male reproductive health. Because the incidents rate of testis cancer is rising. In Denmark 1% of all men will get the testis cancer. Semen quality is declining in some European countries, and congenital abnormalities appeared to be more common than earlier. All these change may be due to harmful hormonal effects on the unborn. But we need much more research to find out whether endocrine disruptors are to be blamed. " "There is only one way to find out the cause... much more research."
Dr. Skakkebaek explained that there is three important researches in male reproductive problems. First research is multi center studies to investigate whether semen quality is declining or not in the world. Second is the research on mechanisms of EDCs, which can be cleared by molecular and clinical studies. The third is the identification and screening of chemicals to clarify which chemicals are EDCs. In the United States, US-EPA has already initiated the screening. Dr. Skakkebaek said that international co-operation is necessary, since the issue of EDCs are global.
During his stay in Japan, he met many scientists and researchers in the field of spermatogenesis, such as Dr. Iwamoto (St. Marianne university), Dr. Iguchi (Yokohama City University), and Dr. Mori (Kyoto University) and discussed the issues and exchanged information. It was great opportunity to develop further collaboration, and various international collaborative researches are about to begin to solve EDC issues.
We, as a consumer, have to make effort to get reliable information and make action to solve the EDC issues.
The Ministry of Agriculture, Forestry and Fishery in Japan (MAFF) accepts public comments on their proposal on GMO Food labeling. Proposal A; labeling obligation on "GMO" and "not segregated" foods, volunteer labeling on "GMO free", and Proposal B; volunteer labeling on all "GMO", "not segregated" and "GMO free" foods. Japan Offspring Fund sent comments to the MAFF to support proposal A. We also received some letters from our Japanese members that they send comments to the MAFF to support proposal A.
In addition, we received warm support form the US. Center for Science in the Public Interest (CSPI), a citizen's group in Washington DC with 1 million member, specializing food safety, sent a comment to support proposal A to the MAFF.
International Association of Consumer Food Organization (IACFO), an organization which works on food policy issues, and consisting of the CSPI, the Food Commission UK, and the Japan Offspring Fund, also send a comment to the MAFF to support proposal A. The reasons to support proposal A were as follows.
"While some consumers welcome the use of new technologies such as genetic engineering, others seek to purchase food that is produced using more traditional methods. If a food has been produced with genetically engineered ingredients, that fact should be clearly indicated on the label, just as foods that have been irradiated, or made with organic ingredients, disclose those facts on the label. The disclosure of such information is necessary to permit consumers to exercise free choice in the marketplace and "vote with their pocketbooks." Which is essential in a free market economy. If consumers are not given adequate information, then they cannot make informed purchasing decisions, and producers cannot respond with the types of products that consumers want to purchase. Thus by requiring labeling, the Ministry can help ensure that free market forces operate properly."
"Those consumers who which to avoid purchasing genetically engineered food may wish to do so for several reasons. For example, some consumers may have safety concerns about genetically engineered foods. It is possible, for instance, that a gene for an allergen could be transferred from one food to another food to which a consumer would not normally be allergic. Without proper labeling, consumers would not know whether a genetically engineered food contains an allergen."
"Many major producers of GMOs' have agreed to abide by labeling requirements
similar to those proposed by the Ministry. Novartis began labeling its
genetically modified corn in 1996 and has urged its customers to label
their products as coming from genetically engineered seeds. Wolfgang
Samo, head of agribusiness at Novartis has stated that egenetically
enhanced products are overall superior to conventional ones. Industry
should have many reasons to label themcIf we believe in the right
to choose for consumers, the industry cannot reasonably argue against
labels facilitating this choice.' Recently, the Monsanto Company has
agreed to label genetically engineered products sold in the European
Union (EU). The EU issued a regulation requiring labeling of GMO's in
1997. While Monsanto initially opposed the EU regulation, the company
now states that it will comply with the requirement."
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