This article briefly discusses the articles included in this special collection, reviews the history of military environmental exposures, both man-made and naturally occurring, and then reviews the exposure hazards of concern to US military members who have served in armed conflict over the past more than 40 years. Then, a special program within the Department of Veterans Affairs (VA) that addresses these concerns of veterans is described.
This issue of JOEM contains this Introduction, 14 original articles, and a letter in response to one of the articles. Several of these articles come from the staff of the New Jersey War Related Illness and Injury Study Center (WRIISC), several are from the US Army Public Health Command, four are from the Naval Health Research Center, and a few are from elsewhere. Each of these articles focuses on the two most recent US wars, in Afghanistan and Iraq. The war in Afghanistan, Operation Enduring Freedom (OEF), began in October 2001 and continues as this issue goes to press. The war in Iraq, Operation Iraqi Freedom (OIF), began in March 2003 and concluded in August 2010; the remaining actions in Iraq are now referred to as Operation New Dawn (OND).
The editor has attempted to present an array of studies looking at correlates of veterans' symptoms,1–3 at veterans' exposures of concern,4 at specific health outcomes and whether they are related to proximity to known open-air burn pits,5–8 and at possible health effects of exposure to two specific hazards—the largest known sulfur mine fire in history9 and depleted uranium.10
One of the most worrisome health problems being seen in the veterans from these two conflicts is pulmonary deficits, as yet ill defined. Two original articles looking at respiratory health in this population from different perspectives have been included.11,12 There is also an article that is the product of a working group with recommendations on how to further evaluate the pulmonary problems that are being seen.13 The letter to the editor by representatives of the Department of Defense specifically addresses some of the working group's recommendations.14
In recognition of the fact that JOEM is primarily for physicians who see patients, there is an article dedicated to risk communication and application of risk communication principles to discussions with patients about their exposure concerns.15
UNKNOWN EXPOSURES AND UNKNOWN LEVELS OF EXPOSURE
One limitation of much of the literature about environmental exposures in combat, including this special issue, is measurement of exposures. Attempts to conduct risk assessments on exposures of concern and their impact on health outcomes are imprecise because there are no real-time personal exposure data while in a combat theater. There are surrogates for some exposures, such as deployment within 2, 3, and 5 miles of a base with a known open-air burn pit and length of deployment to that assignment,5–8 linking ambient particulate matter data with personnel, medical, and meteorological data,11 and being within 50 miles of an exposure incident.9 Extensive modeling and testing of the model has been used with some combat zone exposures, for example, demolition of the munitions depot at Khamasiyah in March 1991, which subsequently was determined to have contained Sarin gas–loaded munitions.16
Unfortunately, there are shortcomings inherent in each of these methods, which are addressed by the authors in each article. As a result, it is often not feasible to accurately distinguish an exposure of concern versus an actual exposure, nor to accurately quantify an actual exposure to determine the likelihood of adverse health outcome. That is why there is such interest in exposures of concern, in lieu of simply exposures. That is also why risk communication is so important in these discussions.
BRIEF HISTORY OF MAN-MADE ENVIRONMENTAL HAZARDS OF WAR
This special issue focuses on environmental exposures in OEF/OIF. But any discussion of environmental exposures in combat should start with an understanding of the history of the topic. Members of the military while preparing for, or actively engaged in, combat have faced myriad man-made environmental exposure hazards for at least three millennia. Some would have been easy to identify by their distinctive odor or signature health effect, such as blistering agents in World War I. Others would have gone unnoticed or unidentified or both until it was too late to avoid the health effects, such as chemical weapons dropped on Kurdish civilians in Iraq in 1988.
There is evidence that military forces were environmentally exposed to chemical agents during conflict for more than 3000 years. Chinese writings dating back to about 1000 BCE contain hundreds of recipes for the production of poisonous or irritating smokes for use in military campaigns along with numerous accounts of their use.17
Solon of Athens is said to have used hellebore roots (a purgative) to poison the water in an aqueduct leading from the Pleistrus River around 590 BCE during the siege of Cirrha, in the First Sacred War in Greece.17 Ancient Greek historians recount that Alexander the Great encountered poison arrows and fire incendiaries in India at Indus Basin in the fourth century BCE.18 During the siege of Plataea in 428 BCE, wood was saturated with pitch and sulfur to generate arsenic smoke, and then burned under the walls of the city to produce poisonous choking fumes (as well as fear and panic).19,20
One of the earliest recorded reactions to the use of chemical agents was from Rome. Struggling to defend themselves from the Roman legions, Germanic tribes poisoned the wells of their enemies, with Roman jurists declaring “armis bella non venenis geri,” meaning “war is fought with weapons, not with poisons.” Yet the Romans themselves resorted to poisoning wells of besieged cities in Anatolia in the second century BCE.17,18
Historian and philosopher David Hume, in his history of England, recounts how in the reign of Henry III (r.1216 to 1272) the English Navy destroyed an invading French fleet by blinding the enemy fleet with “quicklime,” the old name for calcium oxide.21
Leonardo da Vinci in the 15th century proposed a machine to fire shells containing a powder of sulfur, arsenic, and verdigris (copper acetate) to be thrown onto enemy ships with the use of small catapults. This mixture would become an asphyxiant when breathed by the enemy. It is unknown whether this powder was ever actually used.17,22 Also during the 15th century CE, arsenic smokes were used by Christians against the invading Turks at the siege of Delium.23
In the 17th century, during sieges, armies attempted to start fires by launching incendiary shells filled with sulfur, tallow, rosin, turpentine, saltpeter, and/or antimony. Even when fires were not started, the resulting smoke and fumes provided a considerable distraction. Although their primary function was never abandoned, a variety of fills for shells were developed to maximize the effects of the smoke.17,23
The first recorded international agreement banning the use of chemical weapons is the Strasbourg Agreement of 1675. France and the Holy Roman Empire were the signatories. The treaty was signed on August 27, 1675.24
In 1854, Lyon Playfair, a British chemist, proposed using a cacodyl cyanide-filled artillery shell against enemy ships during the Crimean War. The British Ordnance Department rejected the proposal as it was considered to be as bad as poisoning enemy wells.25
Military medical professionals are first known to be involved with systematically correcting exposures to environmental toxins during World War I. A historical review noted that medical professionals in the French Army identified and attempted to correct carbon monoxide poisoning from machine guns firing in enclosed spaces, such as a tank.26
BRIEF HISTORY OF NATURAL ENVIRONMENTAL HAZARDS OF WAR
Man-made hazards were not the only ones that military personnel needed to take heed of. For millennia and even today, the weather and natural environment are important components of planning a battle. Generals, kings, emperors, presidents, and madmen have attempted to use topography, weather, and weather predictions to the advantage of their troops and their causes. In many cases, harsh weather played a decisive role in the outcome of a battle. Armies came to expect harsh weather, whether it was monsoons, desert heat, severe storms, tropical jungles, or freezing cold, yet sometimes it seemed that the absence of the expected weather was also a problem.
In 54 BCE, Julius Caesar prepared to assault England with the entire Roman army, including 800 vessels. The weather forced him to wait a month for favorable winds to sail from the Normandy coast. Once at sea, his fleet came to almost a complete standstill due to a dramatic drop in the wind, leaving his forces to drift slowly into the North Sea. They finally ended up rowing their way to the eastern British shore. The invading force was so far behind schedule in his campaign that Caesar tried to attack the enemy without taking time to properly beach his ships. The next day, a severe storm damaged practically all the Roman vessels. Caesar and his men worked diligently to repair their vessels and this lack of focus on the battle aided the British immensely.27
In 1274, Kublai Khan sent a fleet with an estimated 23,000 warriors in 300 large vessels and 400 to 500 smaller craft to capture Japan. With superior weapons and tactics and more experienced officers, the Mongol armies won some early battles; however, a severe typhoon sank most of the ships and the invaders. In the spring of 1281, Kublai Khan tried again, this time with two forces totaling 140,000 troops in 4400 ships. Another typhoon, this one lasting 2 days, destroyed most of the invading force again.28,29
In 1709, Swedish king Charles XII became the first of several great European invaders to lead his men on a long march of death and exhaustion through the Russian winter. The winter attrition of the mighty Swedish forces during “the Great Northern War” had a great psychological impact and a great hand in the Swedish king's defeat.30
There were several battles during the US Revolutionary War whose outcome was heavily influenced by the weather. On December 25, 1776, George Washington managed to get most of his forces across the Delaware River despite severe winter weather. That force was able to surprise the Hessian troops stationed in Trenton and capture, wound, or kill more than 200 at a cost of only four wounded.29 In August 1776, a combined British and Hessian troop won a decisive defeat at the Battle of Brooklyn, with American losses outweighing British by about 5 to 1. Nevertheless, during the second night of the battle, an extremely dense fog descended on Brooklyn and under cover of this fog, General Washington was able to evacuate 9000 of his remaining forces to Manhattan.31
One hundred years after Charles XII failed, in 1812, Napoleon assembled the largest army Europe had ever seen—more than 600,000 strong—to march into Russia. He had not heeded the lesson of the Swedish king and was not worried that winter was approaching. Napoleon's soldiers succeeded in capturing and plundering Moscow, but as they marched away from the ruined city the temperatures fell to −40°C. The soldiers fell to frostbite and starvation. In one 24-hour period, 50,000 horses died from the cold. Of the 600,000 men who marched into Russia, only 150,000 would make it home. It was the beginning of the end for Napoleon's empire.30
Several years later, the weather still did not cooperate with Napoleon. In the Battle of Waterloo in 1815, weather again played a decisive role. A torrential rainstorm hampered Napoleon's forces and he postponed the French attack on the British. This delay allowed the Prussian army to catch up to the French army and combine with the British forces to defeat Napoleon's army.32
In the summer of 1941, Hitler's “blitzkrieg” forces had planned to take over Russia within 5 months or before the onset of the winter season. As the German offensive, with more than three million men, encountered the earliest and coldest winter in 50 years, the German armies and vehicles were literally frozen in their tracks. Their momentum was lost and Hitler was never able to successfully achieve victory on the Eastern Front.33
In the early centuries, personal hygiene during times of war was not much different at home and in a theater of war, primarily because the situation at home was not especially hygienic. As the personal hygiene and living conditions of civilians have improved, Service members have come to recognize that this would be another area of discomfort and deprivation during a time of war.
Armies and navies have been sent into battle in inhospitable environments for well more than 2000 years. In some cases, such as those mentioned earlier, the ambient environment and severe weather are major determinants of the outcome of the entire battle or even the whole war. In other cases, extreme weather, lack of hygiene, and other local factors have significant effects only on the individual members of the military, for example, frostbite in US soldiers in Korea, and malaria in US Service members in Vietnam. Although the technology of prevention and the methods of Force Protection have evolved tremendously in the past 100 years, there are still many issues unresolved. In many cases, the solution or preventive measure implemented comes with its own potential hazards and service member concerns, for example, pesticides and flea collars used by US troops in the Gulf War, and prophylactic immunizations administered to deploying troops since the Revolutionary War.
EXPOSURE CONCERNS AMONG VETERANS OF PREVIOUS CONFLICTS
Understandably these exposures have lead to concern or worry about the exposure. The bulk of the accumulated data about environmental health concerns of veterans has occurred since the Vietnam War and demonstrates that a large portion of military personnel are concerned about a large number of environmental exposures.34–37 What is striking is the consistency of these soldiers' concerns about exposures over the past four decades (Figure 1). Among three groups of veterans (Vietnam [1961–1975], the Gulf War [1990–1991], and Bosnia and Kosovo [1993–1995 and 1998–1999, respectively] conflicts combined), the percent prevalence of concerns about local food, harsh weather, insect bites, petrochemicals and fuels, missiles and weapon systems, and burning trash and burning feces is high (generally 50% or greater) and similar across conflicts (Fig.1).
Many veterans returning from the Gulf War reported increases in debilitating multisymptom illnesses. These unexplained symptoms resulted in great concern about potential environmental exposures during deployment. This in turn led to a significant amount of media attention and a large number of legislative committee hearings, both federal and state. Many of these symptoms have often been ascribed to a laundry list of environmental exposures, both individually and in combination, about which service members or researchers were and are concerned.35–41 This list includes: anthrax vaccine, bites from insects and rodents, pesticides and fleas collars, oil well fires, multiple vaccinations, pyridostigmine bromide, Sarin gas (nerve agent), Mission Oriented Protective Posture gear (specialized clothing and equipment designed to protect the wearer against nuclear, biological, and chemical contamination on the battlefield), mycoplasma infection, and many others. Unfortunately, there is still not a definitive answer for the cause or causes of these symptoms, nor is there a fully consistent symptom clustering among these veterans.
In large part, in response to these unexplained symptoms in Gulf War veterans, in 2001, the VA established two specialty centers for addressing the issues of veterans with postdeployment health problems and concerns and veterans with medically unexplained symptoms. These are the WRIISCs and they are located at the VA Medical Centers in Washington, DC (DC WRIISC), and East Orange, New Jersey (NJ WRIISC). In 2007, another WRIISC was created at the VA Medical Center in Palo Alto, California (PA WRIISC). The WRIISC program was established with a four-part mission: to provide state-of-the-art services to postdeployment veterans and their health care providers through (1) clinical evaluations and clinical services; (2) research; (3) education; and (4) risk communication. Further discussion of these four program elements has already been published.34
The initial two WRIISCs reported on the first 53 National Referral Program Veterans seen for comprehensive evaluations between January 2002 and March 2004.34 These veterans had on average six or more diagnoses. The top three diagnoses were chronic fatigue syndrome, neurotic depression, and post-traumatic stress disorder. The three most common presenting complaints were chronic pain, joint/muscle pain, and headaches.
These 53 veterans reported a mean of 9.2 exposures of concern to health hazards during their deployment.34 Eighty percent of these veterans served in the Gulf War. The top five environmental exposures of concern reported by this cohort were as follows:
Diesel, kerosene, other petrochemicals (n = 32)
Oil well fire smoke (n = 29)
Pesticides (n = 25)
Protective gear/alarms (n = 24)
Paints, solvents, or other petrochemicals (n = 24)
Other exposures of concern commonly cited include the following:
Anthrax vaccine (n = 27)
Hepatitis B vaccine (n = 24)
Pyridostigmine bromide pills (nerve agent prophylaxis) (n = 24)
Within 1 mile of ammunition or missiles (n = 24)
Insect bites (n = 23)
The DC WRIISC also reported on their initial experience with Gulf War veterans. The top 10 exposure concerns of this cohort of veterans can be seen in Table 1. As becomes obvious, when comparing Figure 1, the earlier-reported concerns, and Table 1, there is considerable overlap in the exposures of concern among veterans from different conflicts.
According to the latest figures released by the VA, as of September 30, 2011, 1,396,477 military members who have served in OEF/OIF/OND have separated and become veterans.42 The exact number of new veterans of OEF/OIF/OND who have been exposed to environmental hazards, are concerned about having been exposed, or both is unknown, but is likely to be between 20% and 35%, or between one quarter and one half of a million.4 According to the same VA report, approximately 53% of the new veterans have received health care from the VA. That means that 47% or 656,000 veterans have not turned to the VA for care. Some of those veterans are likely to have concerns about exposures they encountered during their deployment(s) and they are likely to seek health care from non-VA physicians. It is the hope of the authors and the guest editor that the collection of articles in this issue of JOEM will help to prepare the readers to be better able to help our country's veterans.
The author thanks Lisa M. McAndrew, PhD, for her invaluable assistance with the manuscript for this article.