In response to an article about my friend Dave Dowdell and his fight for life against cancer caused by his exposure to Agent Orange in Vietnam, a veteran widow expressed sympathy. She said that she is still fighting with the VA and the government for benefits several years after her husband’s passing. She asked if there is any current research linking Agent Orange with cancer?
Not being an expert on Agent Orange, nor a medical practitioner, I can only point to research. It is also fair to say that medical professionals based their linkage on probabilities and facts.
The government could accept the evidence or give veterans and their families a hard time. What do We the People want them to do?
“Agent Orange exposure increases skin cancer risk in Vietnam veterans
Sunday 2 February 2014 - 12am PST
Veterans / Ex-ServicemenCancer / OncologyDermatologyMelanoma / Skin Cancer
The Vietnam War ended in 1975, but - even 4 decades later - high rates of non-melanoma invasive skin cancer are reported in Vietnam veterans exposed to the controversial herbicide Agent Orange, according to a new study published in the journal Plastic and Reconstructive Surgery.
A potent jungle defoliant, millions of gallons of Agent Orange were sprayed across Vietnam in order to remove the forest cover concealing enemy troops and to destroy crops.
Containing a highly toxic dioxic contaminant called TCDD, Agent Orange is linked to a wide range of diseases in humans, including many cancers.
No one knows exactly how many people were exposed to TCDD during the Vietnam War, but about 1.5 million Americans served in Vietnam during the most intense period of herbicide use.”
“Does Agent Orange cause cancer?
Researchers use 2 main types of studies to try to determine if a substance or exposure causes cancer.
One type of study looks at cancer rates in different groups of people. Such a study might compare the cancer rate in a group exposed to a substance versus the rate in a group not exposed to it, or compare it to what the expected cancer rate would be in the general population. But studies of people can sometimes be hard to interpret, because other factors that are hard to account for might be affecting the results.
In studies done in the lab, animals are exposed to a substance (often in very large doses) to see if it causes tumors or other health problems. Researchers may also expose normal cells in a lab dish to the substance to see if it causes the types of changes that are seen in cancer cells. In these types of studies, other factors are easier to control for, but it’s not always clear if the results in lab dishes or animals would be the same in humans, for a number of reasons.
In most cases neither type of study provides definitive evidence on its own, so researchers usually look at both human and lab-based studies when trying to determine if something might cause cancer.
Studies in people
Studies of Vietnam veterans provide some of the most direct evidence of the health effects of Agent Orange exposure.
The Centers for Disease Control and Prevention (CDC), the US Air Force, and the Department of Veterans Affairs (VA) have conducted studies in thousands of Vietnam veterans. However, most of these studies have been limited by the fairly small number of people who were highly exposed to Agent Orange. About a dozen states have also conducted studies of their veterans, and some of them have yielded cancer risk information. A series of studies of Australian Vietnam veterans has also provided some information on cancer risk.
Because of the limits of the Vietnam veteran studies, studies of 3 other groups have provided important information on the potential cancer-causing properties of Agent Orange exposure:
Vietnamese soldiers and civilians exposed to the same herbicides as United States service personnel, often for more prolonged periods (although there have been few thorough health studies in these populations)
Workers exposed to herbicides in other settings, such as herbicide manufacturing workers, herbicide applicators, farmers, lumberjacks, and forest and soil conservationists, who often had much higher blood dioxin levels than Vietnam veterans
People exposed to dioxins after industrial accidents in Germany, Seveso (Italy), and California, and after chronic exposures at work and in the environment
Each of these groups differs from the Vietnam veterans in the characteristics of the people exposed, the nature of the dioxin exposures, and other factors such as diet and other chemical exposures.
Taken together, these studies have looked at possible links between Agent Orange (or dioxin) and a number of cancer types.
Soft tissue sarcoma: Most studies in Vietnam veterans have not found an increase in soft tissue sarcomas. However, soft tissue sarcomas have been linked to phenoxy herbicide exposure in a series of studies in Sweden and in some studies of industrially exposed workers. Many studies of farmers and agricultural workers show an increase in soft tissue sarcomas, which may relate to herbicide exposure. Soft tissue sarcomas have also been linked to dioxin exposure in some chemical manufacturing workers and in some other workplace studies.
Non-Hodgkin lymphoma: Most studies of Vietnam veterans have not shown an increase in non-Hodgkin lymphoma (NHL). But several studies have found a link between phenoxy herbicide exposure (usually on the job) and NHL. Some studies of farmers and agricultural workers also suggest this association, although not all studies have found such a link.
Hodgkin disease: Most studies of Vietnam veterans have not found an increase in Hodgkin disease.
However, Hodgkin disease has been linked to phenoxy herbicide exposure in some other studies. Many studies of farmers and agricultural workers show an increase in Hodgkin disease, which may relate to herbicide exposure.
The link between Hodgkin disease and dioxin exposure specifically is less clear, as studies have given mixed results.
Lung and other respiratory cancers: Most studies of Vietnam veterans have not shown an increase in respiratory cancers, such as those of the lung, trachea (windpipe), and larynx (voice box). Most studies of people exposed to herbicides at work, such as herbicide manufacturing workers, herbicide applicators, and farmers have not found an excess risk of lung cancer.
Most studies of groups of people highly exposed to dioxin after industrial accidents have not found an increase in respiratory cancers. However, chronic exposures to high levels of dioxin in the workplace have been linked with increased risk of respiratory cancers in some studies.
Prostate cancer: Most studies of Vietnam veterans have not found an excess risk of prostate cancer, but results from a few studies have suggested a possible link. For example, a recent study in veterans found that exposure to Agent Orange was linked to an increased risk of developing more aggressive forms of prostate cancer.
Studies of other groups have also yielded mixed results. Most studies of people exposed to phenoxy herbicides at work do not show an excess of prostate cancer. However, some studies have found a small excess risk of prostate cancer related to dioxin exposure.
Multiple myeloma: Most studies of Vietnam veterans have had too few cases of multiple myeloma (a type of immune system cancer that affects the bones) to be helpful in determining if there is a risk.
However, other studies of people exposed to pesticides, herbicides, and/or dioxins have suggested a possible link. Several studies of farmers and agricultural workers have reported a small increase in risk of multiple myeloma, although some studies show no excess risk.
Gastrointestinal (GI) cancer: Cancers of the GI system – esophagus, stomach, liver, pancreas, colon, and rectum – have been extensively studied in Vietnam veterans, groups with herbicide exposure in the workplace, and people exposed to dioxins. Most of these studies have not found a link between these exposures and any GI cancer.
Brain tumors: Most studies have not found a link between Vietnam service, workplace herbicide exposure, or dioxin exposure, and brain tumors.
Breast cancer: As most Vietnam veterans are men, in whom breast cancer is very rare, few studies have looked for possible links between Agent Orange and breast cancer. Some studies looking at exposure to dioxin in the workplace or from industrial accidents have noted a possible link, but others have not, so more research is needed in this area.
Other cancers: Few studies have looked at a possible link between Agent Orange exposure and other cancers, including cancers of the nose and nasopharynx (upper part of the throat), cervix, endometrium (uterus), ovaries, liver and bile ducts, bone, kidneys, bladder, testicles, or skin, or leukemias other than chronic lymphocytic leukemia (in veterans themselves, as opposed to their children).
Leukemia and other cancers in the children of veterans: A few studies have pointed to a possible link between a father’s exposure to Agent Orange or other herbicides and leukemia in his children. But several other studies have not found links with leukemia or other childhood cancers.”