Kelly Young, Edited by David G. Fairchild, MD, MPH, and Jaye Elizabeth Hefner, MD

Occupational exposure to pesticides is associated with elevated risk for amyotrophic lateral sclerosis

(ALS), according to a case­control study in JAMA Neurology.

Roughly 150 patients with ALS were matched with 125 controls without a neurodegenerative condition. Participants completed surveys about their occupational exposures to pollutants, and blood samples were tested for 122 persistent neurotoxic organic pollutants.

Survey data indicated that occupational pesticide exposure was associated with increased risk for developing ALS (odds ratio, 5.09). Blood tests suggested significantly increased ALS risk for the following pollutants: pentachlorobenzene, cis­chlordane, polychlorinated biphenyl (PCB) 175, PCB 202, and polybrominated diphenyl ether (PBDE) 47.

The authors conclude that these chemicals “may represent modifiable ALS disease risk factors.” Lead exposure, surprisingly, had a protective effect for ALS, as did PCB 151 and PBDE 66.

Personal comment: In every episode of House, the staff would break into the patient’s home to find any toxins that may be causing the symptoms. We rarely ask about travel, occupation, or possible work related exposure to toxins, when evaluating patients. And there are who­knows how many patients suffering needlessly because no doctor ever thought to ask if the patient works in a garden and what pesticides are used.


JAMA Neurology article (Free)

JAMA Neurology editorial (Subscription required)

Background: NEJM Journal Watch Neurology coverage of guideline on ALS treatment and management(Free)