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over time and no easy solutions have energed. Federal leadership needs to find innovative ways to assure that all families have access to care.
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The last area that we are addressing is inadequate training of physicians. Our lead reporting system has shown that even in areas with high lead levels, physicians are not screening children for lead poisoning. Our experience with problems in communities 11ke McFarland has shown us that physicians have inadequate knowledge of problems such as pesticide poisoning, air pollution, and how to identify and report possible environmental health problems. In partnership with the private sector (Children's Hospital Oakland), the American Academy of Pediatrics and the ATSDR, California has been developing a curriculum to train physicians in pediatric environmental health. The course will be given for the first time on September 7 and 8, 1990. We hope that it will become a model for training all physicians who take care of children.
Thank you again for the opportunity to testify. Our state already has taken several steps to address the effects of environmental exposure on children. But much more needs to be done. All research in this area is hindered by inadequate levels of funding and by lack of appropriate priority setting. Our children are an investment in the future. We must take the necessary steps to ensure their health and well being, and thus to ensure our competitiveness as a nation. We urge you to take a close look at the problem and to develop federal policies that will enhance our ability to prevent harmful environmental exposures to children.
Chairman MILLER. Thank you. Dr. Jukes. STATEMENT OF THOMAS H. JUKES, PH.D., DEPARTMENT OF BIOPHYSICS, UNIVERSITY OF CALIFORNIA, BERKELEY, CA Mr. JUKES. My name is Thomas Jukes. I am Professor of Biophysics at the University of California.
Chairman MILLER. We will have to get you to speak up a little bit. It is a little hard for people in the back to hear.
Mr. JUKES. Should I get closer to the microphone? Chairman MILLER. Yes. There you go. Mr. JUKES. I have been a professor of Biophysics at the University of California in Berkeley since 1963. I have a Ph.D. degree in Biochemistry. And I have also worked in nutrition, vitamins, and cancer chemotherapy.
My wife and I have seven young grandchildren. My main involvement in cancer in children is that I received the Bruce F. Cain Memorial Award in 1987 in the American Association for Cancer Research, for my participation in work on methotrexate. This was the first compound that was successfully used for treating leukemia in children. Before that, childhood leukemia had no treatment. And my work on this was when I was at Lederle Laboratories from 1947 to 1952.
I support the proposal of the committee to investigate environmental toxins in children's health. This needs careful scientific analysis, because there have been recent panics. There has been more discussion about pesticides than any other topic this morning, and I was very glad to hear some attention given to lead, and to second-hand cigarette smoke, by the last two speakers.
It is quite easy to arouse fear by telling parents that their children may be poisoned by their food. In 1989, it was announced by FDA that Chilean grapes were contaminated with cyanide. As a result, tons of perfectly good fruit were dumped into the garbage, and the Chilean fruit industry was severely damaged.
The contaminated grapes that started the panic were found by the FDA to contain three micrograms of cyanide in each of two grapes. Now, the amount of cyanide normally present in lima beans is 100 micrograms per gram. So this panic was completely unnecessary. And I notice in the papers again this morning that the Chileans were threatening to sue the FDA for this matter.
I dwell upon these figures because this illustrates the basic principle of toxicity, that the dose alone makes the poison. And as analytical methods are refined, we can detect more substances in foods and produce at very, very low levels.
The use of pesticides in food production must benefit the consumer. And as has been brought out this morning by Congressman Stark, the person who applies the pesticides must be protected.
The value of pesticides is that pests are destroyed. And that pests consume and contaminate crops. Moths grow on food, and produce cancer-causing toxins. Moths are killed by fungicides, which are pesticides. One pesticide has saved more lives, and prevented more disease, especially in children in the third world, than any other chemical in history. That pesticide was DDT.
The yields of fruit and vegetables are increased by the use of pesticides that are applied by controlled methods that have been approved. Fruits and vegetables are recommended by all leading health authorities as variable for the prevention of cancer. Any program that deprives children of fruits and vegetables is removing nutritionally important foods that prevent cancer.
What are the risks? It is encouraging that during the years 1940 to 1983, in which synthetic pesticides came into use, life expectancy has risen from 63.6 years to 74.6 years.
Pesticide residues are not present in detectable amounts in most foods. The California Department of Food and Agriculture tested over 14,000 food samples in 1988, and again in 1989. No residues could be detected in more than 70 percent of the samples, both years. Residues were less than 50 percent of legal limits in another 20 percent of the samples. The legal limits provide about 100-fold margin of safety. Only one-quarter of one percent had residues above the limits. And these figures are on the table at the back of my testimony.
These figures tell us that to protect our children, we should be focusing primarily on something different from pesticide residues. There are many important problems. Lead poisoning is one. And I should mention here that when, before the introduction of organic pesticides, lead arsenate was used on foods. And you could see the lead arsenate on pears in the supermarket in the 1940s. So that is one thing that pesticides have done.
I would list also passive exposure to cigarette smoke, fetal alcohol syndrome. The fetal alcohol syndrome, I have written warnings against that. And my wife is a schoolteacher, and she sees the results of the fetal alcohol syndrome in children in her class.
Also malnutrition is a very important problem for children.
It is generally concluded that the incidence of cancer could be substantially reduced by improving the diet. This conclusion comes from comparing diets in different countries with incidence of various types of cancer. High-fat diets may definitely be a cause. More fiber in the diet, and more fruits and vegetables, are strongly advised. These conclusions are based on incidence of cancer in human beings.
The levels of carcinogens naturally present in the diet are thousands of times greater than residues of synthetic pesticides. Scorched or burned foods contain highly potent carcinogens, as shown by animal tests, reported by Sugimura in Japan. Plants produce toxic substances, some of which are carcinogens, to protect themselves against insects. Professor Ames estimates that 50 percent of all chemicals, either natural or synthetic, that have been tested, are carcinogenic at high levels of a toxic.
There are lots of carcinogens always in food. And we protect ourselves against their effects by means of natural anti-cancer substances, such as antioxidants. And of course, these can be added to an improved diet.
Of course, very large doses of carcinogens, such as cigarette smoke, alcohol, or sunburn can overcome the natural means of protection.
The Mayo Clinic Nutrition Letter, in June, 1989, said:
America's food supply is abundant, and generally quite safe, more so than in the past. We believe hysteria over pesticide residues is unwarranted. The pesticide residue limits are often set several hundred times lower than the level that caused no effects in test animals.
The results of the FDA market basket study show that after cleaning, peeling, and cooking, foods generally contain less than one-hundredth the amount of pesticide residues established by international organizations. Increasing your consumption of fruits and vegetables may lower your risk of developing some types of cancer. In general, you can feel confident in the safety of what you eat.
Now, Alar and UDMH have been mentioned several times today. On February 26, 1989, the TV program “60 Minutes” showed a red apple with a skull and crossbones. And the announcer stated that the "most potent cancer-causing agent in our food supply is a substance sprayed on apples.”
This TV program, which caused public panic nationwide, was based on data supplied by the Natural Resources Defense Council. I disagree with their conclusions.
Tests with Alar showed that it did not cause increased cancer in either mice or rats when fed at doses as high as one percent of the diet. The red apple on TV would have contained about 0.2 milligrams of Alar, or one-third of a microgram of UDMH.
When food containing Alar is processed, Alar breaks down to UDMH and succinic acid. The rate of breakdown was five percent to nine percent in processed applesauce, with a top level of 44 parts per billion of UDMH.
UDMH tested negatively for cancer in rats. And in mice, was negative at 10 and 20 parts per million in drinking water.
Tumors were observed in 20 percent of animals that received 80 parts per million, but 80 percent of the mice died prematurely, indicating that the minimum toxic dose had been exceeded. But tumors were probably caused by toxicity to the liver. And these findings show the existence of a threshold for the toxic action of UDMH.
The Natural Resources Defense Council said in their publication that "UDMH is the greatest source of the cancer risk from pesticides identified by NRDC.” The levels of intake of UDMH, from the EPA, FDA, and USDA data, are 1.6 micrograms daily for a 20-kilo child.
Now, let's compare that with some of the other things that we eat. Our normal intake of arsenic is about 1,000 micrograms daily. And of cadmium, 200 to 500 micrograms daily. Both arsenic and cadmium are regarded as human carcinogens.
We produce about 200 micrograms of steroid hormones daily, which are regarded as carcinogens. Extrapolation of carcinogenicity to such low levels as 1.6 micrograms is scientific nonsense, even if the biological tests were valid, which obviously was not the case.
California State Health Director, Dr. Kenneth Kizer, noted that giving up fruits and vegetables will surely result in more cases of cancer than would ever result from trace pesticide residues. Alar reduces the dropping of apples that rot on the ground and harbor pests, including molds. Molds on apples produce patulin, a suspected carcinogen. So that is the latest I have on that.
The NRDC declared on November 14, 1989, that “use of a chemical whenever the benefits outweigh the risks is absolutely anathema to the scientific community.”
Actually, we spend much of our lives taking actions in which the benefits outweigh the risks. Dr. Sanford Miller, a former director of the FDA Bureau of Foods, reportedly was quoted as saying in 1990, “The risk of pesticide residues to consumers is effectively zero. This is what some 14 scientific societies representing over 100,000 microbiologists, toxicologists and food scientists, said at the time of the ridiculous Alar scare."
Now, Dr. Richard H. Adamson, who is Director of the Division of Cancer Etiology of the National Cancer Institute, made the following statement on August 22, 1990: “At the present time, I am unaware of evidence that suggests that regulated and approved pesticide residues in food contribute to the total human cancer in the United States. Epidemiologic studies do suggest that certain herbicides and pesticides increase the risk for certain types of neoplasms in those persons who are heavily exposed to them, especially pesticide applicators,” as we have heard today.
Now, when DDT was banned, of course, the risk to farmworkers was greatly increased, because they switched to perithion, and that caused the deaths of several farmworkers, when DDT had never caused the death of a single worker.
Age-adjusted mortality rates among white children, ages zero to 14 years, have decreased by 35 percent between 1973 and 1986. The rate of cancer deaths at all sites in 1973 was 5.6 per 100,000 in this age group. And in 1986, was 3.6 per 100,000.
The incidence rate for acute lymphocytic leukemia, which I am interested, increased between 1973 and 1980. But the mortality rate decreased from 1.4 in 1973 to 0.7 in 1986, possibly because of chemotherapy. Data are from the National Center for Health Statistics.
My conclusions regarding pesticide residues in foods are as follows:
Analysis of foods show that in most cases, pesticide residues were not detected, and in nearly all other cases, the residues were within tolerance limits. These findings show that the problem is a minor one, regardless of other circumstances.
A National Cancer Institute spokesperson stated he was unaware of evidence that suggested that pesticide residues in food contribute to the toll of human cancer in the United States, as I have just stated.
Third, various public health authorities agree that protection against cancer by fruits and vegetables outweighs any effects of pesticide residues.
Fourth, plant protectant chemicals-pesticides-make a second contribution to the prevention of cancer by destroying molds that produce carcinogens in foods, and that are found in organic foods.
The apple scare was based on mouse tests for UDMH that were unreliable, incomplete, and flawed by toxicity.
Finally, the public is highly sensitive to scare stories about food, and scientists should at all times try to supply authoritative information on this topic.
I am fully aware of the political implications that Congressman Stark mentioned this morning. But surely we must base our deci