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FIGURE 3 Major Synthetic Route to 2,4-dichlorophenoxyacetic acid (2,4-))

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A third important and very toxic pesticide, pentachlorophenol (PCP) is known to undergo reactions leading to the formation of the 1, 2, 3, 4, 5, 6, 7, 8, 9-octachlorodibenzo-p-dioxin. The toxicity and harmful effects of this compound has not been fully evaluated but are perhaps less than the tetrachloro or the hexachloro analogs (cf. Figure 5):12

12-14

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1J. E. Johnson, Subcommittee on Energy, Natural Resources, and the Environment, April 15, 1970.

2. “Encyclopedia of Chemical Technology", 2d Ed. article by J. D. Doedens, vol. 5, p. 325-335.

3J. Kimmig and K. H. Schulz. Dermatologica 115, 540-6 (1957).

* M. Tomita, S. Leda, and M. Narisada. Yakugaku Zasshi, 79, 186-92 (1959); Chem. Abstr. 53, 13152f (1959).

5 H. Bauer, K. H. Schulz, and U. Speigelberg. Arch. Gewerbepath. Geweibehyg. 18, 538–55 (1961); Chem. Abstr. 56, 1720d (1962).

8 G. R. Higginbotham et. al. Nature 220, 702–3 (1968).
7 G. R. Bell. Botan. Gaz. 118, 133-6 (1956).
$P. C. Kearney et. al., Residue Reviews 29, 139 (1969).

R. B. Hemmett, Jr. and S. D. Faust. ibid. 29, 191-207 (1969). 10 O. M. Aly and S. D. Faust. J. Agr. Food Chem. 12, 541 (1964). 11 L. E. Mitchell. “Organic Pesticides in the Environment," Advan. Chem. Ser. 60, 17 (1966).

12 W. Sandermann, H. Stockmann, and R. Casten. Chem. Ber. 90, 690–2 (1957). 13 M. Kulka, Can. J. Chem. 39, 1973-6 (1961).

14 L. Denivelle, R. Fort, and P. Van Hal. Bull. Soc. Chim. France, 1960, 1538-43. Supplemental:

*Degradation of Herbicides" ed. by P. C. Kearney and D. D. Kaufman, Marcel Dekker, Inc., N.Y. (1969) p. 350.

Mr. WELLFORD. There is another compelling reason why the Government should take action to suspend Silvex and the cancelled and exempted uses of 2,4,5-T. It is time to dispel the secrecy which has shrouded these herbicides. In the hearing of this committee on April 7, we discussed the mysterious attempts to suppress the Bionetics report which revealed the birth defect properties of these herbicides.

I would remind the committee that as early as the fall of 1966, the Bionetics Laboratory, in a contract report to the National Cancer Institute, disclosed test results which showed that 2,4,5-T caused birth defects in mice. These results were concealed from other teratologists and the rest of the scientific community for 3 years.

In this time, no action was taken by the Government to minimize human exposure. Only in August of last year did Dr. Samuel Epstein succeed in prying the report loose for use by the Panel on Teratogenicity of the Mrak Commission. Unfortunately, the treatment of the Bionetics reports was not an isolated case.

As a general rule, data on the toxicology, efficacy, chemical identity and epidemiology of these chemicals has never been collected, disseminated or stored in ways which allow for rapid and easy access by interested scientists or the general public. It is imperative that data on these herbicides and on all pesticides which relate to the safety of the public and environmental quality be a matter of open record.

Few people realize the extent to which analysis of these chemicals has become a closed system for insiders only. Biological testing of these chemicals to anticipate the consequences of human exposure is neither impartial nor necessarily competent. This testing is performed through confidential contracts between the manufacturers and commercial testing laboratories. The possibilities, indeed the incentives, for abuse are obvious.

As one PRD staffer recently told us, “The manufacturer runs the tests he wants to run, selects the test results which are most favorable to him and sends them to us. Rarely, if ever, will PRD ask him to submit additional data.” Under the present system, a pesticide company has a clear incentive to avoid a laboratory which is embarrassingly thorough in its tests.

This initial testing is not open to independent scrutiny. Furthermore no independent tests are performed by USDA when the pesticide is presented for registration. Registration is, in effect, a paper procedure which largely accepts at face value data submitted by the manufacturer as to the safety and effectiveness of a product.

There is no access to the registration procedure for independent scientist who might want to comment before a new chemical agent is released in the environment. There is, for example, no publication of a new registration prior to its effective data.

Similarly, even well into cancellation proceedings, review of potential hazards of a pesticide remains a closed shop for Government and industry insiders.

The advisory committee, for which we are still awaiting appointment in the case of DDT, is appointed by USDA in collaboration with the NAS meeting in secret. USDA and company representatives may consult with the committee, but the public may not. All formal and informal discussions between the agencies, industry, and the committee of experts remain secret.

Presumably, if proceedings reach the stage of a public hearing, independent scientists and representatives of environmental and consumer groups may be able to appear, but even this is not clear.

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J. E. Johnson, Subcommittee on Energy, Natural Resources, and the Environment, April 15, 1970.

2 "Encyclopedia of Chemical Technology", 2d Ed. article by J. D. Doedens, vol. 5, p. 325-338.

3 J. Kimmig and K. H. Schulz. Dermatologica 115, 540-6 (1957). - M. Tomita, S. Veda, and M. Narisada. Yakugaku Zasshi, 79, 186-92 (1959); Chem. Abstr. 53, 13152f (1959).

5 H. Bauer, K. H. Schulz, and U. Speigelberg. Arch. Gewerbepath. Geweibehyg. 18, 538-55 (1961); Chem. Abstr. 56, 1720d (1962).

& G. R. Higginbotham et. al. Nature 220, 702–3 (1968).
7 G. R. Bell. Botan. Gaz. 118, 133-6 (1956).
8 P. C. Kearney et. al., Residue Reviews 29, 139 (1969).
.R. B. Hemmett, Jr. and S. D. Faust. ibid. 29, 191--207 (1969).
10 O. M. Aly and S. D. Faust. J. Agr. Food Chem. 12, 541 (1964).

11 L. E. Mitchell. “Organic Pesticides in the Environment," Advan. Chem. Ser. 60, 17 (1966).

12 W. Sandermann, H. Stockmann, and R. Casten. Chem. Ber. 90, 690-2 (1957). 13 M. Kulka, Can. J. Chem. 39, 1973-6 (1961).

14 L. Denivelle, R. Fort, and P. Van Hai. Bull. Soc. Chim. France, 1960, 1538–43. Supplemental:

"Degradation of Herbicides” ed. by P. C. Kearney and D. D. Kaufman, Marcel Dekker, Inc., N.Y. (1969) p. 350.

Mr. WELLFORD. There is another compelling reason why the Government should take action to suspend Silvex and the cancelled and exempted uses of 2.4,5-T. It is time to dispel the secrecy which has shrouded these herbicides. In the hearing of this committee on April 7, we discussed the mysterious attempts to suppress the Bionetics report which revealed the birth defect properties of these herbicides.

I would remind the committee that as early as the fall of 1966, the Bionetics Laboratory, in a contract report to the National Cancer Institute, disclosed test results which showed that 2,4,5-T caused birth defects in mice. These results were concealed from other teratologists and the rest of the scientific community for 3 years.

In this time, no action was taken by the Government to minimize human exposure. Only in August of last year did Dr. Samuel Epstein succeed in prying the report loose for use by the Panel on Teratogenicity of the Mrak Commission. Unfortunately, the treatment of the Bionetics reports was not an isolated case.

As a general rule, data on the toxicology, efficacy, chemical identity and epidemiology of these chemicals has never been collected, disseminated or stored in ways which allow for rapid and easy access by interested scientists or the general public. It is imperative that data on these herbicides and on all pesticides which relate to the safety of the public and environmental quality be a matter of open record.

Few people realize the extent to which analysis of these chemicals has become a closed system for insiders only. Biological testing of these chemicals to anticipate the consequences of human exposure is neither impartial nor necessarily competent. This testing is performed through confidential contracts between the manufacturers and commercial testing laboratories. The possibilities, indeed the incentives, for abuse are obvious.

As one PRD staffer recently told us, “The manufacturer runs the tests he wants to run, selects the test results which are most favorable to him and sends them to us. Rarely, if ever, will PRD ask him to submit additional data.” Under the present system, a pesticide company has a clear incentive to avoid a laboratory which is embarrassingly thorough in its tests.

This initial testing is not open to independent scrutiny. Furthermore no independent tests are performed by USDA when the pesticide is presented for registration. Registration is, in effect, a paper procedure which largely accepts at face value data submitted by the manufacturer as to the safety and effectiveness of a product.

There is no access to the registration procedure for independent scientist who might want to comment before a new chemical agent is released in the environment. There is, for example, no publication of a new registration prior to its effective data.

Similarly, even well into cancellation proceedings, review of potential hazards of a pesticide remains a closed shop for Government and industry insiders.

The advisory committee, for which we are still awaiting appointment in the case of DDT, is appointed by USDA in collaboration with the NAS meeting in secret. USDA and company representatives may consult with the committee, but the public may not. All formal and informal discussions between the agencies, industry, and the committee of experts remain secret.

Presumably, if proceedings reach the stage of a public hearing, independent scientists and representatives of environmental and consumer groups may be able to appear, but even this is not clear.

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