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Last Edited: 8/8/2013

Acute health effects of the Cantara Metam-Sodium spill: An epidemiologic assessment
Written: 1992

On July 14, 1991, a major pesticide spill occurred in a remote area of Northern California near the town of Dunsmuir.  Due to a train derailment, 19,000 gallons of the herbicide metam sodium were released into the Sacramento River.  Nearly all aquatic life in a 45-mile segment of the river from the spill site to Lake Shasta was killed as the chemical flowed downstream.  Individuals near the river reported a variety of symptoms from exposure to vapors released by the herbicide.  This report, prepared by the California Department of Health Services' Environmental Epidemiology and Toxicology Program, examines health effects of the spill reported to the local medical community from July 14 to August 16, 1991.



During the one-month period of study, 705 cases were identified. These individuals accounted for a total of 848 medical visits. The number of medical evaluations was approximately equally distributed between the hospital emergency rooms, private physicians, and triage center. Most of the cases were from Dunsmuir (70.6%), Mt. Shasta (7.2%) and Castella (6.4%) which were the three communities closest to the spill site. By age distribution, the largest number of cases were in the 30-39

age group. Relatively few cases were recorded for ages 50 and over. For each age group, more females than males reported symptoms. Seven hospitalizations were recorded. There were four respiratory-related admissions, two cases of possible syncope (fainting), and one case of a cardiac arrhythmia in a person involved in initial clean

up activities. All were discharged by July 28. There were no fatalities.



An analysis of Dunsmuir cases suggested that nearly 14% of the population within the city limits sought medical evaluation. Within the Dunsmuir area, it appeared that exposures occurred on both sides of the river at distances of up to 1500 feet away from the river. 





Full report (Size:  5 MB)

Suggested Citation

  • Goldman LR, Hewitt D, Kreutzer RA. Acute health effects of the Cantara metam-sodium spill: An epidemiologic assessment. California Department of Health Services, Environmental Epidemiology and Toxicology Program, Emeryville, CA. June 1992.