The article ''Veterans and Agent Orange: A Debate That Eludes Scientific Resolution" {Federal Page, Sept. 28} was both a light at the end of a very long tunnel and a disappointment to one who has been involved in the Agent Orange litigation since 1979. A disappointment in that many misconceptions still exist surrounding this controversy, and the press has yet to uncover the real truth. Such misconceptions have been created by the chemical companies that manufactured the product, by the Veterans Administration and by the judge who oversaw the litigation in New York.

For example, the article states that ''studies have given only disappointingly vague answers about whether dioxins cause severe health problems.'' This is simply not true. Animal studies have shown for years the cause-and-effect relationship between dioxin, an ingredient in Agent Orange, and such potentially deadly medical conditions as sarcoma, lymphoma, leukemia, immune system defects, birth defects and bone, nasal, brain, skin, liver, pancreatic, thyroid, gall-bladder, palate, tongue and respiratory cancer.

Also, less serious conditions have been proven almost conclusively, porphyria cutanea tarda (a severe liver condition) and chloracne (severe skin condition). What the article failed to indicate is that the chemical companies, the Veterans Administration and Judge Weinstein have refused to look at these. However, they were sufficient for the EPA to suspend all domestic use of the herbicide as far back as April 15, 1970, because of a ''potential health hazard to humans.''

Because this country does not experiment on humans, animal studies have always been the most reliable and best understood studies available. Also the most prominent members of the medical community have supported such associations and have testified to this under oath in a variety of different forms. Those opposed to the veterans do not want to accept this inevitable conclusion because of the inevitable consequences. There were potentially 2.1 million veterans exposed to Agent Orange in Vietnam.

What would happen if the courts accepted their cases and allowed them to go to trial? What would happen if the Veterans Administration accepted their right to compensation and medical benefits? And what would happen to the chemical companies if a jury found them responsible?

The second misconception is that the Agent Orange litigation is over. This is far from the case. On Sept. 15, petitions for certiorari were filed in the U.S. Supreme Court in regard to all the Agent Orange cases. In the meantime, all action by the U.S. District Court in New York is stayed. As Yogi Berra once said, ''It ain't over till it's over.'' The Supreme Court will be the final arbiter as to the veterans' rights.

Additionally, the article states that the VA study ''made no connections between the cancers and Agent Orange.'' However, the report clearly states in the abstract that ''Agent Orange may be suspected. . . .''

One cannot fault The Post's reporter for repeating the many misconceptions surrounding Agent Orange. But the veterans now need a journalistic uncovering of the entire Agent Orange controversy. There is a story here that needs to be told, a story about a country that has turned its back on its brave fighting men in their time of most need. A country that would never think of leaving the wounded unattended on the battlefield but who will today leave the victims of the Vietnam War without any recourse for the wounds they now have because of their exposure to Agent Orange in Vietnam.

Wayne M. Mansulla