Malcolm Gladwell's May 31 article, "Scientists Temper Views on Cancer-Causing Potential of Dioxin" states that one of the reasons scientists are questioning whether dioxin is as potent a carcinogen as currently believed is that epidemiological studies involving Vietnam veterans exposed to the dioxin contaminants contained in Agent Orange "have failed to show that dioxin has the same effect on humans as it does on laboratory animals." If such "reasons" are prompting the Environmental Protection Agency or other governmental agencies to consider relaxing the standards for dioxin, we can reasonably expect a host of Love Canal horror stories to grace the pages of this paper in the years to come.
As I recently reported to Secretary Edward Derwinski of the Department of Veterans Affairs, there is an overwhelming body of credited scientific research which confirms that the probable cause of various cancers contracted by Vietnam veterans and the birth defects among their progeny is exposure to the dioxin contaminants contained in the defoliant Agent Orange.
Regrettably, there is also substantial evidence to indicate that the epidemiological studies involving Vietnam veterans were intentionally manipulated to prevent any probability of finding a relationship between health problems and exposure to dioxins. Indeed, the irregularities surrounding the Agent Orange studies have prompted numerous officials and epidemiologists to request a full-scale investigation of the "science" so heavily relied upon by those who would deny the existence of a link between dioxin and adverse health effects.
The Agent Orange charade of the last several years demonstrates that science has been poorly served by those who so readily manipulated the available data to foreclose the Agent Orange debate. Only those who have been duped by the disingenuous studies and foolishly remain resistant to acknowledging the direct link between dioxin and debilitating diseases could have the audacity to suggest that scientific views could or should be tempered.
E. R. ZUMWALT JR.
Admiral, U.S. Navy (Retired)
Arlington The writer was chief of naval operations from 1970 to 1974.