Guest guest Posted January 23, 2003 Report Share Posted January 23, 2003 I thought this was interesting... Misty http://www..com Pesticide Makers Attempt to Show EPA Their Products Are Harmless Pesticide makers are hoping to persuade the EPA that if healthy adults suffer no adverse effects after consuming a bit of pesticide, then restrictions should be relaxed. by Sharon Begley The Wall Street Journal The World Health Organization lists aldicarb, a pesticide, as " extremely hazardous. " It calls the pesticide dichiorvos " highly hazard-ous " ; the U.S. Environmental Protection Agency classifies it as a " possible human carcinogen. " Yet, if you are healthy and up for an adven-ture, pesticide makers will pay you $500, $800, even $1,500 to imbibe in or the other, either once or daily for 18 days with your morning OJ. The controversy over the scientific value and ethics of testing pesticides on people is approaching, full boil, spurred by intense pressure from the pesticide industry to loosen federal pol-icies and by a law suit that manufacturers filed against the EPA to make it accept data from such experiments. At last count, 14 studies of 11 pesticides have been sub-mitted since 1996. The push for human testing was triggered by the 1996 Food Quality Pro-tection Act. In exchange for allowing traces of car- cinogenic pesticides to re-main on food (previously illegal), the act requires the EPA to use an additional " safety factor " in setting allowed residue levels, to protect children and fetuses. Pesticide makers have that safety factor in their cross hairs, hoping to persuade the EPA that if healthy adults suffer no adverse effects after consuming a bit of pesticide, then restrictions should be relaxed. THE RECENT EXPERIMENTS dosing people with pesticides haven’t exactly covered themselves in glory, ethically speaking. In one testing dichlorvos, in Scotland, many of the volunteers were cash- strapped college students. The possibility of financial coercion always is an ethical no-no. And in several places, the consent form referred to dichlorvos as a " drug " and said it was used as a medicine, misleading volunteers, as The Wall Street Journal reported in 1998. But leave aside ethics concerns for a mo-ment and focus on the science, for unless an experiment on humans yields valuable data it is by definition unethical. The argument in, favor is simple: " There is no substitute for the knowledge gained from human volunteer studies, " as Monty Eberhart of Bayer CropScience, a major pesticide maker, puts it. True ,but only in the abstract. The current round of studies have used small numbers (10 to 50, typically) of healthy adults, raising doubts about the studies statistical power. " If you see an effect, you can be reasonably confident in that finding even if you used only 10 or 15 people, " says toxicologist Michael Gallo of the Environmen-tal and Occupational Health Sciences Institute in Piscataway, N.J. " But to be confident that you have no effect is much more difficult. You may just happen to have studied 10 people who are not sensitive to the compound. To prove a negative you need many more people, " probably hundreds. The existing studies border on junk science for another reason: You can't volunteer for them unless you're a healthy adult. Given this " voluntarism bias, " as epidemiologist Lynn Gold-man of Johns Hopkins University, Baltimore, calls it, there are real doubts that a level found to produce no adverse effects in such a group also is safe for children, the ill and the elderly. When you run a toxicology study, you don't ask, " So, what does this chemical do, anyway? " You define an endpoint, such as, " How does this chemical affect acetyl cholinesterase activity? " " This is the basic fallacy of relying on these studies, " says Dr. Goldman, a former EPA pesticide official. The critical effects are things like developmental neurotoxicity in children and fetuses, and those might reflect chemical pathways unrelated to whatever is causing toxicity in adults. Organophosphate pesticides have been found to alter gene expression in the brains of fetal rats, for instance, yet are tested for how they inhibit enzyme activity in adult red blood cells. BUT LET'S SAY the endpoints are chosen properly, and the tests have enough subjects to offer statistical power. Let's say, too, that the studies adhere to ethical standards. Are they OK now? You still have an inherent ethical problem. When people volunteer to test the safety of drugs, " those Phase 1 trials are for things in- tended to make people better, " says bioethicist Jeffrey Kahn of the University of Minnesota, Minneapolis. " If the purpose is to allow industry to get higher levels of pesticides into the environment, then it's very questionable. " When an EPA Science Advisory Panel studied the acceptability of experimenting with pesticides on people, it concluded in 2000 that if the study is conducted with rigorous ethical controls, if there is no other way to fill data gaps and if the goal is to protect public health, then the EPA should consider it. " We felt that only under the most extraordinary circumstances should human testing be done, " says toxicolo-gist Ronald Kendall of Texas Tech University in Lubbock, who chaired the panel. Interestingly, very few experiments would likely meet those guidelines. As Prof. Gall, who is viewed as sympathetic to industry, asks, " For existing pesticides, where we have a great deal of human data from epidemiology and biomonitoring of farmworkers exposed to pesti-cides, why do we need these studies? " Hoping for scientific and political cover, the EPA has asked a panel of the National Academy of Sciences to answer that. Its report is expected late this year. -- Does it concern anyone else that on top of everything else, the study only lasts for 18 days? Can that really be representative of a lifetime of ingesting pesticides? Misty. http://www..com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 23, 2003 Report Share Posted January 23, 2003 Thanks, Misty. So the chemical companies are still doing it! This reminds me of an experience I had as a 13 year old child in about 1950: I was born and raised on a big dairy farm. This was a few years after DDT became available to farmers and Rachel Carson had not yet written her book. The chemical company that made DDT called a county wide meeting of farmers to demonstrate the total safety of their product " once and for all " . We all gathered at the foot of the wide entry stairs to the front entry of the Grange Hall (where all big farmer meetings were held). It was a fine summer evening so the meeting of such a large # of farmers as attended did not have to crowd into the hall. When we were all gathered the chemical company rep was introduced, standing on the steps, and he said that this clear glass mug in his hand was filled with pure DDT. He had a few farmers come up and smell it since, having used so much of the pure stuff, they could recognize that that was what it really was. The rest of us could see that the oily liquid had the color and consistency of pure DDT. He had an assistant standing by who, the rep explained, was going to drink the entire mug. And, by God, that is exactly what he did! He chugged it down and handed the empty mug back to the rep. We waited for the guy to drop dead. However, after about 5 minutes of pregnant pause and nothing happened, the rep suggested that the alarmists were exactly that. We all knew that it only took a couple of cups of the pure stuff, to a 50-100 gallon sprayer, for effective fly killing. This guy had just drunk a full mug of the PURE STUFF and did not drop dead! I often wondered, later, how much they had paid that guy to do that and whether he was a disposable lackey who was replaced with another disposable lackey for each demonstration. My dad's and my response to the demo was that we were not nearly so careful where we sprayed DDT after that--and we had not been very careful before. I can remember spraying the cows, their feed, the barn, the milking parlor, milk storage area and environs while becoming soaked to the skin myself. This was done as often as it was needed to keep the cows and the barn fly free--at least once a week. It was considered a mark of cleanliness to have a fly-free barn, since before DDT no one had ever been able to do so. We poor, chemically unsophisticated farmers had no idea that DDT was a " cumulative poison " for humans that took 20-50 years to have it's deadly effect. We would not have even known what a " cumulative poison " was. Of course the chemical company rep knew! And now this? I guess they figure: Why tinker with a an effective approach? Walt Stoll, MD - <mistytrepke Wednesday, January 22, 2003 11:20 PM Pesticide Makers Attempt to Show EPA Their Products Are Harmless I thought this was interesting... Misty http://www..com Pesticide Makers Attempt to Show EPA Their Products Are Harmless Pesticide makers are hoping to persuade the EPA that if healthy adults suffer no adverse effects after consuming a bit of pesticide, then restrictions should be relaxed. by Sharon Begley The Wall Street Journal The World Health Organization lists aldicarb, a pesticide, as " extremely hazardous. " It calls the pesticide dichiorvos " highly hazard-ous " ; the U.S. Environmental Protection Agency classifies it as a " possible human carcinogen. " Yet, if you are healthy and up for an adven-ture, pesticide makers will pay you $500, $800, even $1,500 to imbibe in or the other, either once or daily for 18 days with your morning OJ. The controversy over the scientific value and ethics of testing pesticides on people is approaching, full boil, spurred by intense pressure from the pesticide industry to loosen federal pol-icies and by a law suit that manufacturers filed against the EPA to make it accept data from such experiments. At last count, 14 studies of 11 pesticides have been sub-mitted since 1996. The push for human testing was triggered by the 1996 Food Quality Pro-tection Act. In exchange for allowing traces of car- cinogenic pesticides to re-main on food (previously illegal), the act requires the EPA to use an additional " safety factor " in setting allowed residue levels, to protect children and fetuses. Pesticide makers have that safety factor in their cross hairs, hoping to persuade the EPA that if healthy adults suffer no adverse effects after consuming a bit of pesticide, then restrictions should be relaxed. THE RECENT EXPERIMENTS dosing people with pesticides havenâ?Tt exactly covered themselves in glory, ethically speaking. In one testing dichlorvos, in Scotland, many of the volunteers were cash- strapped college students. The possibility of financial coercion always is an ethical no-no. And in several places, the consent form referred to dichlorvos as a " drug " and said it was used as a medicine, misleading volunteers, as The Wall Street Journal reported in 1998. But leave aside ethics concerns for a mo-ment and focus on the science, for unless an experiment on humans yields valuable data it is by definition unethical. The argument in, favor is simple: " There is no substitute for the knowledge gained from human volunteer studies, " as Monty Eberhart of Bayer CropScience, a major pesticide maker, puts it. True ,but only in the abstract. The current round of studies have used small numbers (10 to 50, typically) of healthy adults, raising doubts about the studies statistical power. " If you see an effect, you can be reasonably confident in that finding even if you used only 10 or 15 people, " says toxicologist Michael Gallo of the Environmen-tal and Occupational Health Sciences Institute in Piscataway, N.J. " But to be confident that you have no effect is much more difficult. You may just happen to have studied 10 people who are not sensitive to the compound. To prove a negative you need many more people, " probably hundreds. The existing studies border on junk science for another reason: You can't volunteer for them unless you're a healthy adult. Given this " voluntarism bias, " as epidemiologist Lynn Gold-man of Johns Hopkins University, Baltimore, calls it, there are real doubts that a level found to produce no adverse effects in such a group also is safe for children, the ill and the elderly. When you run a toxicology study, you don't ask, " So, what does this chemical do, anyway? " You define an endpoint, such as, " How does this chemical affect acetyl cholinesterase activity? " " This is the basic fallacy of relying on these studies, " says Dr. Goldman, a former EPA pesticide official. The critical effects are things like developmental neurotoxicity in children and fetuses, and those might reflect chemical pathways unrelated to whatever is causing toxicity in adults. Organophosphate pesticides have been found to alter gene expression in the brains of fetal rats, for instance, yet are tested for how they inhibit enzyme activity in adult red blood cells. BUT LET'S SAY the endpoints are chosen properly, and the tests have enough subjects to offer statistical power. Let's say, too, that the studies adhere to ethical standards. Are they OK now? You still have an inherent ethical problem. When people volunteer to test the safety of drugs, " those Phase 1 trials are for things in- tended to make people better, " says bioethicist Jeffrey Kahn of the University of Minnesota, Minneapolis. " If the purpose is to allow industry to get higher levels of pesticides into the environment, then it's very questionable. " When an EPA Science Advisory Panel studied the acceptability of experimenting with pesticides on people, it concluded in 2000 that if the study is conducted with rigorous ethical controls, if there is no other way to fill data gaps and if the goal is to protect public health, then the EPA should consider it. " We felt that only under the most extraordinary circumstances should human testing be done, " says toxicolo-gist Ronald Kendall of Texas Tech University in Lubbock, who chaired the panel. Interestingly, very few experiments would likely meet those guidelines. As Prof. Gall, who is viewed as sympathetic to industry, asks, " For existing pesticides, where we have a great deal of human data from epidemiology and biomonitoring of farmworkers exposed to pesti-cides, why do we need these studies? " Hoping for scientific and political cover, the EPA has asked a panel of the National Academy of Sciences to answer that. Its report is expected late this year. -- Does it concern anyone else that on top of everything else, the study only lasts for 18 days? Can that really be representative of a lifetime of ingesting pesticides? Misty. http://www..com Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 23, 2003 Report Share Posted January 23, 2003 Dr. Walt- That is the stuff nightmares are made of! What happened to the people in your community, your family? Have you attempted to detox the DDT? Misty http://www..com , <waltstoll@k...> wrote: > Thanks, Misty. > > So the chemical companies are still doing it! > > This reminds me of an experience I had as a 13 year old child in about 1950: > > I was born and raised on a big dairy farm. This was a few years after DDT > became available to farmers and Rachel Carson had not yet written her book. > The chemical company that made DDT called a county wide meeting of farmers > to demonstrate the total safety of their product " once and for all " . > > We all gathered at the foot of the wide entry stairs to the front entry of > the Grange Hall (where all big farmer meetings were held). It was a fine > summer evening so the meeting of such a large # of farmers as attended did > not have to crowd into the hall. When we were all gathered the chemical > company rep was introduced, standing on the steps, and he said that this > clear glass mug in his hand was filled with pure DDT. He had a few farmers > come up and smell it since, having used so much of the pure stuff, they > could recognize that that was what it really was. The rest of us could see > that the oily liquid had the color and consistency of pure DDT. > > He had an assistant standing by who, the rep explained, was going to drink > the entire mug. And, by God, that is exactly what he did! He chugged it down > and handed the empty mug back to the rep. We waited for the guy to drop > dead. However, after about 5 minutes of pregnant pause and nothing > happened, the rep suggested that the alarmists were exactly that. We all > knew that it only took a couple of cups of the pure stuff, to a 50- 100 > gallon sprayer, for effective fly killing. This guy had just drunk a full > mug of the PURE STUFF and did not drop dead! > > I often wondered, later, how much they had paid that guy to do that and > whether he was a disposable lackey who was replaced with another disposable > lackey for each demonstration. My dad's and my response to the demo was > that we were not nearly so careful where we sprayed DDT after that- -and we > had not been very careful before. I can remember spraying the cows, their > feed, the barn, the milking parlor, milk storage area and environs while > becoming soaked to the skin myself. This was done as often as it was needed > to keep the cows and the barn fly free--at least once a week. It was > considered a mark of cleanliness to have a fly-free barn, since before DDT > no one had ever been able to do so. > > We poor, chemically unsophisticated farmers had no idea that DDT was a > " cumulative poison " for humans that took 20-50 years to have it's deadly > effect. We would not have even known what a " cumulative poison " was. Of > course the chemical company rep knew! > > And now this? I guess they figure: Why tinker with a an effective approach? > > Walt Stoll, MD > > - > <mistytrepke> > > Wednesday, January 22, 2003 11:20 PM > Pesticide Makers Attempt to Show EPA Their > Products Are Harmless > > > I thought this was interesting... > Misty > http://www..com > > > Pesticide Makers Attempt to Show EPA Their Products Are Harmless > > Pesticide makers are hoping to persuade the EPA that if healthy > adults suffer no adverse effects after consuming a bit of pesticide, > then restrictions should be relaxed. > > by Sharon Begley > The Wall Street Journal > > The World Health Organization lists aldicarb, a pesticide, as > " extremely hazardous. " It calls the pesticide dichiorvos " highly > hazard-ous " ; the U.S. Environmental Protection Agency classifies it > as a " possible human carcinogen. " Yet, if you are healthy and up > for an adven-ture, pesticide makers will pay you $500, $800, even > $1,500 to imbibe in or the other, either once or daily > for 18 days with your morning OJ. > > The controversy over the scientific value and ethics of testing > pesticides on people is approaching, full boil, spurred by intense > pressure from the pesticide industry to loosen federal pol-icies and > by a law suit that manufacturers filed against the EPA to make it > accept data from such experiments. At last count, 14 studies of 11 > pesticides have been sub-mitted since 1996. > > The push for human testing was triggered by the 1996 Food > Quality Pro-tection Act. In exchange for allowing traces of car- > cinogenic pesticides to re-main on food (previously illegal), the > act requires the EPA to use an additional " safety factor " in setting > allowed residue levels, to protect children and fetuses. Pesticide > makers have that safety factor in their cross hairs, hoping to > persuade the EPA that if healthy adults suffer no adverse > effects after consuming a bit of pesticide, then restrictions should > be relaxed. > > > THE RECENT EXPERIMENTS dosing people with pesticides havenâ?Tt > exactly covered themselves in glory, ethically speaking. In one > testing dichlorvos, in Scotland, many of the volunteers were cash- > strapped college students. The possibility of financial coercion > always is an ethical no-no. And in several places, the consent form > referred to dichlorvos as a " drug " and said it was used as a > medicine, misleading volunteers, as The Wall Street Journal > reported in 1998. > > But leave aside ethics concerns for a mo-ment and focus on the > science, for unless an experiment on humans yields valuable data it > is by definition unethical. The argument in, favor is simple: " There > is no substitute for the knowledge gained from human volunteer > studies, " as Monty Eberhart of Bayer CropScience, a major pesticide > maker, puts it. > > True ,but only in the abstract. The current round of studies have > used small numbers (10 to 50, typically) of healthy adults, raising > doubts about the studies statistical power. " If you see an effect, > you can be reasonably confident in that finding even if you used > only 10 or 15 people, " says toxicologist Michael Gallo of the > Environmen-tal and Occupational Health Sciences Institute in > Piscataway, N.J. " But to be confident that you have no > effect is much more difficult. You may just happen to have studied > 10 people who are not sensitive to the compound. To prove a negative > you need many more people, " probably hundreds. > > The existing studies border on junk science for another reason: You > can't volunteer for them unless you're a healthy adult. Given this > " voluntarism bias, " as epidemiologist Lynn Gold-man of Johns Hopkins > University, Baltimore, calls it, there are real doubts that a level > found to produce no adverse effects in such a group also is safe for > children, the ill and the elderly. > > When you run a toxicology study, you don't ask, " So, what does this > chemical do, anyway? " You define an endpoint, such as, " How does > this chemical affect acetyl cholinesterase activity? " " This is the > basic fallacy of relying on these studies, " says Dr. Goldman, a > former EPA pesticide official. The critical effects are things like > developmental neurotoxicity in children and fetuses, and those might > reflect chemical pathways unrelated to whatever is causing toxicity > in adults. Organophosphate pesticides have been found to alter gene > expression in the brains of fetal rats, for instance, yet are tested > for how they inhibit enzyme activity in adult red blood cells. > > > BUT LET'S SAY the endpoints are chosen properly, and the tests have > enough subjects to offer statistical power. Let's say, too, that the > studies adhere to ethical standards. Are they OK now? You still > have an inherent ethical problem. When people volunteer to > test the safety of drugs, " those Phase 1 trials are for things in- > tended to make people better, " says bioethicist Jeffrey Kahn of the > University of Minnesota, Minneapolis. " If the purpose is to allow > industry to get higher levels of pesticides into the environment, > then it's very questionable. " > > When an EPA Science Advisory Panel studied the acceptability of > experimenting with pesticides on people, it concluded in 2000 that > if the study is conducted with rigorous ethical controls, if there > is no other way to fill data gaps and if the goal is to protect > public health, then the EPA should consider it. " We felt that only > under the most extraordinary circumstances should human testing be > done, " says toxicolo-gist Ronald Kendall of Texas Tech University in > Lubbock, who chaired the panel. > > Interestingly, very few experiments would likely meet those > guidelines. As Prof. Gall, who is viewed as sympathetic to industry, > asks, " For existing pesticides, where we have a great deal of human > data from epidemiology and biomonitoring of farmworkers exposed to > pesti-cides, why do we need these studies? " > > Hoping for scientific and political cover, the EPA has asked a panel > of the National Academy of Sciences to answer that. Its report is > expected late this year. > > - - > > Does it concern anyone else that on top of everything else, the > study only lasts for 18 days? Can that really be representative of > a lifetime of ingesting pesticides? > > Misty. > http://www..com > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 24, 2003 Report Share Posted January 24, 2003 Hi, Misty. The legacy of DDT is still to be written. The thinning of the eggshells of the predator birds, that almost spelled their extinction, was just the " canary in the coal mine " warning of what was to come. Who knows how much cancer, arthritis, mental problems, etc., will ultimately be shown to have been increased in incidence by the influence of DDT? Since it takes so many years to find out, the chemical companies tend to get away with their lack of concern for the public. I feel that the wellness I have practiced has helped my bodymind detox itself. " There are many paths to the top of the mountain. " Namaste` Walt - <mistytrepke Thursday, January 23, 2003 10:16 AM Re: Pesticide Makers Attempt to Show EPA Their Products Are Harmless Dr. Walt- That is the stuff nightmares are made of! What happened to the people in your community, your family? Have you attempted to detox the DDT? Misty http://www..com , <waltstoll@k...> wrote: > Thanks, Misty. > > So the chemical companies are still doing it! > > This reminds me of an experience I had as a 13 year old child in about 1950: > > I was born and raised on a big dairy farm. This was a few years after DDT > became available to farmers and Rachel Carson had not yet written her book. > The chemical company that made DDT called a county wide meeting of farmers > to demonstrate the total safety of their product " once and for all " . > > We all gathered at the foot of the wide entry stairs to the front entry of > the Grange Hall (where all big farmer meetings were held). It was a fine > summer evening so the meeting of such a large # of farmers as attended did > not have to crowd into the hall. When we were all gathered the chemical > company rep was introduced, standing on the steps, and he said that this > clear glass mug in his hand was filled with pure DDT. He had a few farmers > come up and smell it since, having used so much of the pure stuff, they > could recognize that that was what it really was. The rest of us could see > that the oily liquid had the color and consistency of pure DDT. > > He had an assistant standing by who, the rep explained, was going to drink > the entire mug. And, by God, that is exactly what he did! He chugged it down > and handed the empty mug back to the rep. We waited for the guy to drop > dead. However, after about 5 minutes of pregnant pause and nothing > happened, the rep suggested that the alarmists were exactly that. We all > knew that it only took a couple of cups of the pure stuff, to a 50- 100 > gallon sprayer, for effective fly killing. This guy had just drunk a full > mug of the PURE STUFF and did not drop dead! > > I often wondered, later, how much they had paid that guy to do that and > whether he was a disposable lackey who was replaced with another disposable > lackey for each demonstration. My dad's and my response to the demo was > that we were not nearly so careful where we sprayed DDT after that- -and we > had not been very careful before. I can remember spraying the cows, their > feed, the barn, the milking parlor, milk storage area and environs while > becoming soaked to the skin myself. This was done as often as it was needed > to keep the cows and the barn fly free--at least once a week. It was > considered a mark of cleanliness to have a fly-free barn, since before DDT > no one had ever been able to do so. > > We poor, chemically unsophisticated farmers had no idea that DDT was a > " cumulative poison " for humans that took 20-50 years to have it's deadly > effect. We would not have even known what a " cumulative poison " was. Of > course the chemical company rep knew! > > And now this? I guess they figure: Why tinker with a an effective approach? > > Walt Stoll, MD > > - > <mistytrepke> > > Wednesday, January 22, 2003 11:20 PM > Pesticide Makers Attempt to Show EPA Their > Products Are Harmless > > > I thought this was interesting... > Misty > http://www..com > > > Pesticide Makers Attempt to Show EPA Their Products Are Harmless > > Pesticide makers are hoping to persuade the EPA that if healthy > adults suffer no adverse effects after consuming a bit of pesticide, > then restrictions should be relaxed. > > by Sharon Begley > The Wall Street Journal > > The World Health Organization lists aldicarb, a pesticide, as > " extremely hazardous. " It calls the pesticide dichiorvos " highly > hazard-ous " ; the U.S. Environmental Protection Agency classifies it > as a " possible human carcinogen. " Yet, if you are healthy and up > for an adven-ture, pesticide makers will pay you $500, $800, even > $1,500 to imbibe in or the other, either once or daily > for 18 days with your morning OJ. > > The controversy over the scientific value and ethics of testing > pesticides on people is approaching, full boil, spurred by intense > pressure from the pesticide industry to loosen federal pol-icies and > by a law suit that manufacturers filed against the EPA to make it > accept data from such experiments. At last count, 14 studies of 11 > pesticides have been sub-mitted since 1996. > > The push for human testing was triggered by the 1996 Food > Quality Pro-tection Act. In exchange for allowing traces of car- > cinogenic pesticides to re-main on food (previously illegal), the > act requires the EPA to use an additional " safety factor " in setting > allowed residue levels, to protect children and fetuses. Pesticide > makers have that safety factor in their cross hairs, hoping to > persuade the EPA that if healthy adults suffer no adverse > effects after consuming a bit of pesticide, then restrictions should > be relaxed. > > > THE RECENT EXPERIMENTS dosing people with pesticides havenâ?Tt > exactly covered themselves in glory, ethically speaking. In one > testing dichlorvos, in Scotland, many of the volunteers were cash- > strapped college students. The possibility of financial coercion > always is an ethical no-no. And in several places, the consent form > referred to dichlorvos as a " drug " and said it was used as a > medicine, misleading volunteers, as The Wall Street Journal > reported in 1998. > > But leave aside ethics concerns for a mo-ment and focus on the > science, for unless an experiment on humans yields valuable data it > is by definition unethical. The argument in, favor is simple: " There > is no substitute for the knowledge gained from human volunteer > studies, " as Monty Eberhart of Bayer CropScience, a major pesticide > maker, puts it. > > True ,but only in the abstract. The current round of studies have > used small numbers (10 to 50, typically) of healthy adults, raising > doubts about the studies statistical power. " If you see an effect, > you can be reasonably confident in that finding even if you used > only 10 or 15 people, " says toxicologist Michael Gallo of the > Environmen-tal and Occupational Health Sciences Institute in > Piscataway, N.J. " But to be confident that you have no > effect is much more difficult. You may just happen to have studied > 10 people who are not sensitive to the compound. To prove a negative > you need many more people, " probably hundreds. > > The existing studies border on junk science for another reason: You > can't volunteer for them unless you're a healthy adult. Given this > " voluntarism bias, " as epidemiologist Lynn Gold-man of Johns Hopkins > University, Baltimore, calls it, there are real doubts that a level > found to produce no adverse effects in such a group also is safe for > children, the ill and the elderly. > > When you run a toxicology study, you don't ask, " So, what does this > chemical do, anyway? " You define an endpoint, such as, " How does > this chemical affect acetyl cholinesterase activity? " " This is the > basic fallacy of relying on these studies, " says Dr. Goldman, a > former EPA pesticide official. The critical effects are things like > developmental neurotoxicity in children and fetuses, and those might > reflect chemical pathways unrelated to whatever is causing toxicity > in adults. Organophosphate pesticides have been found to alter gene > expression in the brains of fetal rats, for instance, yet are tested > for how they inhibit enzyme activity in adult red blood cells. > > > BUT LET'S SAY the endpoints are chosen properly, and the tests have > enough subjects to offer statistical power. Let's say, too, that the > studies adhere to ethical standards. Are they OK now? You still > have an inherent ethical problem. When people volunteer to > test the safety of drugs, " those Phase 1 trials are for things in- > tended to make people better, " says bioethicist Jeffrey Kahn of the > University of Minnesota, Minneapolis. " If the purpose is to allow > industry to get higher levels of pesticides into the environment, > then it's very questionable. " > > When an EPA Science Advisory Panel studied the acceptability of > experimenting with pesticides on people, it concluded in 2000 that > if the study is conducted with rigorous ethical controls, if there > is no other way to fill data gaps and if the goal is to protect > public health, then the EPA should consider it. " We felt that only > under the most extraordinary circumstances should human testing be > done, " says toxicolo-gist Ronald Kendall of Texas Tech University in > Lubbock, who chaired the panel. > > Interestingly, very few experiments would likely meet those > guidelines. As Prof. Gall, who is viewed as sympathetic to industry, > asks, " For existing pesticides, where we have a great deal of human > data from epidemiology and biomonitoring of farmworkers exposed to > pesti-cides, why do we need these studies? " > > Hoping for scientific and political cover, the EPA has asked a panel > of the National Academy of Sciences to answer that. Its report is > expected late this year. > > - - > > Does it concern anyone else that on top of everything else, the > study only lasts for 18 days? Can that really be representative of > a lifetime of ingesting pesticides? > > Misty. > http://www..com > > > > > Quote Link to comment Share on other sites More sharing options...
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