18
Apr
ALS Risk Elevated from Toxic Petrochemical Landscape Pesticides, Study Adds to Previous Findings
(Beyond Pesticides, April 18, 2024) University of Michigan researchers have found a statistically significant relationship between heightened risk of amyotrophic lateral sclerosis (ALS) and household exposure to lawn care products and pesticides. The study results were published earlier this month in Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration. The interdisciplinary research team concludes that modifying residential exposure to toxic substances, including pesticides, can play an important role in ALS susceptibility and prognosis. The results build on a substantial body of scientific literature identifying pesticide exposure in various ALS cohort studies. Advocates say that these adverse effects, along with other numerous health and environmental effects, inform their call for the phaseout of toxic pesticide use and the adoption of alternative practices and eco-compatible products.
All participants in this study are patients at the University of Michigan Pranger ALS Clinic with Gold Coast ALS diagnosis, which according to a Muscle & Nerve study refers to the identification of two factors: “progressive motor impairment documented by history or repeated clinical assessment†and “the presence of upper and lower motor neuron dysfunction in a least one body region.†All 367 ALS and 255 control patients were tasked with completing a survey in which they self-reported their exposure to a list of toxic substances at four households over their lives: current home, birth home, and two other homes where they had lived the longest. The researchers split up the patients into three “latent profile†groups. The first group consisted of participants with “high storage of chemicals in a detached garage;†the second group consisted of participants “who had high storage of chemicals in an attached garage;†and the third group consisted of participants “who had low storage of chemicals in a garage.†Generally, group three participants had a higher proportion of participants without ALS than the other two groups with detached and attached garages with higher proportions of chemicals.
The researchers in this study find that pesticide storage, lawn care product storage, and woodworking supplies storage indoors have a statistically significant relationship with poorer ALS survival.
Researchers used a descriptive statistical analysis for their study cohort, using logistic regression models “to estimate one-at-a-time association[s] between residential exposures and case/control status.†The researchers describe their analytical approach as follows: “[M]ultinomial [more than two categories] regression models estimated associations between residential exposures and three onset segments (bulbar, cervical, lumbar); and Cox proportional hazards models estimated associations between residential exposures and post-diagnosis survival.†Onset segments refer to the parts of the body in which patients noticed early indications of motor disfunction consistent with ALS. “Logistic and multinomial regression models were adjusted for military service, sex, education, life-years covered by self-reported residences, and life-years not covered by self-reported residences. The hazards models were adjusted for military service, sex, age at diagnosis, education, log-transformed time between symptom onset and diagnosis, El Escorial criteria [for ALS classification], onset segment, family history of ALS, life-years covered by the self-reported residences, and life-years not covered by the self-reported residences.†The use of logistic and multinomial regression is helpful in determining patient demographics not otherwise covered in the self-reported survey component of the study.       Â
A team of researchers at Michigan Medicine reached similar conclusions in a 2022 study published in International Archives of Occupational and Environmental Health, which indicated that ALS patients working in manufacturing, welding, and chemical jobs “reported higher occupational exposure to metals, particulate matter, volatile organic compounds and combustion pollutants prior to diagnosis.â€
While there is no confirmed treatment or cure for ALS, scientists have engaged in studies to better understand the triggers for this neurodegenerative condition since it was discovered in 1869 by French neurologist Jean-Martin Charcot. Approximately 5,000 new cases of ALS are documented annually in the United States, according to the Centers for Disease Control and Prevention. There is sporadic ALS and familial ALS, with the former making up more than 9 in 10 of all ALS cases. Sporadic ALS means that the condition is not necessarily onset by a particular risk factor or familial history. Cohort studies on sporadic ALS are important to follow because studies such as the one conducted by Michigan Medicine indicate the associated risks that pesticide applicators face with heightened risk of debilitating chronic illnesses such as ALS. Otherwise regarding familial history cases, according to National Institute of Neurological Disorders and Stroke, 25-40 percent of all cases are a result of a defect in the C9orf72 gene and another 12-20 percent of all cases are from a genetic mutation in the SOD1 gene.
Beyond Pesticides tracks the latest scientific literature on adverse health effects of toxic pesticide exposure, including ALS. A 2021 study published in Toxicology, for example, found individuals working or living in areas with frequent neurotoxic herbicide, insecticide, and fungicide (i.e. 2,4-D, glyphosate, carbaryl, and chlorpyrifos) use experience more ALS incidences than the general population. An earlier study published in International Journal of Environmental Research and Public Health in 2020 determined that exposure to agricultural and industrial pesticides, solvents (thinners), electromagnetic fields, and heavy metals predispose humans to ALS. For more studies and analysis, see the Daily News Blog section on ALS.
Advocates, scientists, community leaders, and physicians have engaged with Beyond Pesticides resources to mobilize their communities and institutions to address the longstanding adverse health effects of pesticide exposure. After tracking the latest scientific literature, synthetizing breaking developments and studies through the Daily News Blog, and submitting public comments and testimony at local, state and national levels for over four decades, advocates look to Beyond Pesticides to meet the mission of eliminating toxic petrochemical pesticide use by 2032. See Gateway on Pesticide Hazards and Safe Pest Management to learn about specific pesticide ingredients and the various adverse health impacts they impose on wildlife, ecosystems, and humans. See Pesticide-Induced Disease Database to learn about the impacts of toxic pesticides in contributing to chronic diseases, including ALS. See Non-Toxic Lawns and Landscapes to learn about strategies and access resources to move beyond the use of toxic petrochemicals in lawncare throughout your community.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.Â
Source: Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration
