The drinking water at Marine Corps Base Camp Lejeune was contaminated with the industrial solvent trichloroethylene (TCE), tetrachloroethylene, and other volatile organic compounds from 1953 until 1987, when testing required by the Safe Drinking Water Act uncovered polluted wells. Monthly median levels of the base’s water supply were 70-fold higher than the permissible amount.
TCE is a colorless liquid that readily crosses biological membranes. It turns into vapor quickly and can be absorbed by ingestion, through skin, or by inhalation. In the 20th century, TCE was used for many purposes, including making decaffeinated coffee, dry cleaning, carpet cleaning, and as an inhaled surgical anesthetic for children and women in labor. Today it is used mainly in producing refrigerants and as a degreaser in heavy industry.
The water supply at Camp Lejeune was contaminated by leaking underground storage tanks, industrial spills, waste disposal sites, and an off-base dry cleaning business. Recruits could have ingested TCE in food or water, been exposed through their skin when bathing or showering, or inhaled the highly volatile compound. The Agency for Toxic Substances and Disease Registry has indicated that as many as 1 million military and civilian staff might have been exposed to the contaminated water.
Neurologist Samuel Goldman published a study in 2011 of 99 twin pairs discordant for Parkinson disease that found exposure to TCE was associated with a 6-fold increase in the risk of of the condition.
In 2017, the U.S. government agreed to pay disability benefits totaling more than $2 billion to veterans who had been exposed to contaminated drinking water while assigned to Camp Lejeune between 1953 and 1987. Eight diseases were covered, including several types of cancer and Parkinson’s disease.
Goldman published a much larger study in 2023 that compared the number of Parkinson disease cases and prodromal symptoms among more than 172,000 veterans who had been stationed at Camp Lejeune in Jacksonville, North Carolina, and more than 168,000 at Marine Corps Base Camp Pendleton in Oceanside, California, which did not have contaminated drinking water. Health data was available for more than 158,000 of them during the follow-up period from January 1, 1997 to February 17, 2021.
The veterans averaged 20 years of age when they arrived and spent an average of 2 years living on their respective bases between 1975 and 1985, when TCE contamination at Camp Lejeune was highest. More than 30 years later, 279 veterans at Camp Lejeune and 151 from Camp Pendleton have been diagnosed with Parkinson disease, for a prevalence of 0.33% and 0.21%, respectively. After adjusting for differences in age, sex, race, and ethnicity, the scientists found veterans from Camp Lejeune had a 70% higher rate of Parkinson’s disease than the Camp Pendleton group.
The Camp Lejeune veterans also had higher rates of symptoms known to precede the onset of Parkinson disease such as anxiety, tremor, and erectile dysfunction. Because the recruits were so young when they attended the training camp, they had an average age of 59 when the analysis of their health records ended in 2021. That suggests even more of the Camp Lejeune veterans may eventually develop Parkinson disease because it most commonly occurs after age 60.
Animal studies have confirmed that TCE is a mitochondrial toxin that increases the activity of leucine-rich repeat kinase-2, (LRRK2), which is an enzyme that regulates the movement of proteins and vesicles inside cells. Increased LRRK2 activity damages the function of lysosomes and allows unwanted proteins to accumulate in cells inducing Parkinson-like pathology in the brains of older rats. This research has provided grist for an incipient class action lawsuit from people who decades ago drank contaminated water at the Marine Corps base at Camp Lejeune in North Carolina.
Experts believe that TCE exposure has contributed to more than a doubling of Parkinson disease cases worldwide, from 2.3 million people in 1991 to 6.1 million in 2016. According to the WHO, disability and death due to Parkinson disease are increasing faster worldwide than for any other neurological disorder.
References
Rubin, R., Large Study Links Industrial Solvent in Drinking Water to Parkinson Disease Risk in Camp Jejeune Veterans, June 6, 2023, Volume 329, (#21) 1814-1816.
Goldman S et al. Risk of Parkinson Disease Among Service Members at Marine Corps Base Camp Lejeune, JAMA Neurology, May 15, 2023, doi:10.1001/jamaneurol.2023.1168
Wadman M., TWIST OF FATE, Science, May 5, 2023,
Wadman M, Widely used chemical strongly linked to Parkinson disease, Science, May 15, 2023, doi: 10.1126/science.adi740