The Effects of Herbicide Use in Vietnam

(This is the second of a two-part feature. Part one appeared yesterday.)

WHAT has been the impact of massive infusion of chemical herbicides onto the land and people of Vietnam? In purely statistical terms, the quantity of herbicides dumped is frightening: one sixth of the surface area of Vietnam has been sprayed. There has been major destruction of mangrove forests, hardwood forests, and croplands, with consequent economic and social disruptions-many of which will last for years to come.

Any additional specific effects of the massive herbicide dosage in Vietnam remain largely unknown. Economic damage to forests can be measured; erosion problems and the creation of refugees are visible effects; but lasting chemical effects are more difficult to determine.

Are there herbicide residues in the ground in the sprayed areas which will prevent or alter the regrowth of vegetation? The HAC is uncertain. They do know that bamboo growth may choke off hardwood regeneration and that crabs and weeds may prevent mangrove reforestation, but little is known of the fate of the chemicals themselves.

And what of the direct effect of this chemical dosage on humans? The herbicides used include two chemicals, dioxin and 2,4,5-T, known to cause birth defects, which suggests the possibility that there has been a more permanent, grotesque effect brought by the herbicides:

Dioxin occurs as an impurity in Orange, the principal herbicide used in Vietnam. Its potential importance lies in the fact that it is exceedingly toxic, may be quite stable in the environment, and, being fat soluble, may be concentrated as it moves up the food chain into the human diet. Very rough model calculations suggest that it is not impossible that significant amounts of dioxin are entering the Vietnamese diet.

The HAC studied hospital records in South Vietnam to try to see if dioxin or another chemical herbicide, 2,4,5-T, were implicated in birth defects. Because of the scarcity of data on birth defects and the haphazard way most of them are collected, the HAC found it very difficult to find reliable information. Precise information on quantities of herbicide sprayed, the type of herbicide used, and the location of each spraying mission is classified confidential by the military and is inaccessible to the HAC researchers. The Commission does have enough information to evaluate the magnitude of the problem, however:

"The population directly exposed to 2,4,5-T presumably does not exceed five per cent (and may even be one per cent or less) of the total population of Vietnam, although this must be more accurately determined from precise spray data. This factor alone strikingly dilutes any apparent effects of the spraying on birth statistics when those directly exposed are added to the total statistics of the country, but this effect is even more accentuated by the fact that most of this population is necessarily in remote and usually insecure areas and therefore information regarding medical effects, if any, can only be gradually expected to filter out from the sites of direct exposure. An unknown proportion, but probably quite significant, of the exposed population, consists of Montagnard people whose births are normally at home or in villages and are rarely recorded in the Government of Vietnam medical system or allowed for in the GVN statistics."

Another problem in data collecting is that most of the Vietnam statistics are readily available from hospitals in the province capitals but reports from village and district dispensaries are harder to obtain. In addition, many cases of deformed births are referred out of the country provinces and taken to large city hospitals, so that the affected child is treated in a city (where no spraying has occurred) rather than in the province where the investigators are checking for herbicide effects.

Allowing for all these factors, John Constable, HAC team member, was able to interpret birth statistics from Tay Ninh Provincial Hospital. This hospital serves a heavily defoliated province, and "showed an average stillbirth rate in 1968 and 1969 of 68 per 1000 live births. During this same time, the Tu Do [in Saigon] rate was 27.5 per 1000 and that of the Army sample of the entire country 31.2 per 1000."

In addition, using data from a U. S. Army study, the HAC found "a decided upward trend in stillbirths, moles, and deformities" in the Vietnamese countryside, excluding data from Saigon (where no spraying has taken place, of course). Nevertheless, the HAC is cautious in drawing any conclusions. A scientific approach remains to be developed, concludes the Commission's preliminary report, for "determining the amounts of herbicide residues in the diet and in human tissues, waiting for future research to determine the implications, if any, of whatever levels are found."

Together with Robert Baughman of the Harvard Chemistry Department, Meselson is trying to develop the needed technology for detecting dioxin in food, human tissues, and other materials the HAC collected in Vietnam.

The present intentions of the U. S. government toward continued herbicide use in Vietnam are not too clear. At the project level, most spraying of mangroves and hardwoods has stopped, but crop spraying continues. The government, however, has promised to phase out herbicide use in a "rapid and orderly" manner. This position has led to some speculation that the government is just not going to ship any more herbicides over to Vietnam for use. But the situation is not so simple-the government recently has been buying Blue at a very rapid rate, and is now reported to have stockpiled a supply of Blue (the crop-destruction chemical containing arsenic) to last for the next five years.

THERE is also a pertinent legal aspect to the question of herbicide use in Vietnam. The United States has been ignoring overwhelming world opinion that the use of herbicides in warfare is contrary to international law.

The Geneva Protocol of 1925 prohibits the use in war of asphyxiating, poisonous or other gases, and of all analogous liquids, materials, or devices" as well as "the use of bacteriological methods of warfare." In 1969 the General Assembly of the U. N. adopted a resolution recognizing that the Geneva Protocol prohibits "any chemical agents of warfare-chemical substances, whether gaseous, liquid or solid-which might be employed because of their direct toxic effects on man, animals or plants . . . , " thus including herbicides.

Professor Richard Baxter of Harvard Law School, who has written interpretations of the legal aspects of the Geneva Protocol, writes that "the evidence is by no means conclusive with regard to anti-plant chemicals," but that the weight of opinion in international legal circles is that use of herbicides in war, such as the American spraying in Vietnam, is prohibited by the Protocol.

The 1969 General Assembly resolution was adopted by a vote of eighty to three with thirty-six abstentions. The three who voted against the resolution were the United States, Australia (who has troops in Vietnam), and Portugal (who reportedly uses herbicides and gases against liberation fighters in Africa).

The legal problem serves mainly to question the morality of our military leaders and suggests speculation about whether the U. S. will use massive chemical warfare in other situations. In any discussion of the war in Vietnam, however, speculation about horror seems ludicrous; we are killing and displacing entire peoples for imagined military honor, and it seems that the horror of that may not end for many more years.