Occupational Carbon Monoxide Poisoning in Washington State, 2000–2005

Abstract

Washington State workers’ compensation data can be used to guide prevention efforts focused on occupational carbon monoxide (CO) poisoning. Between 2000 and 2005, a total of 345 individual claims comprising 221 different exposure incidents were identified for the 6-year time period. The construction industry had 43 (20%) CO incidents, followed by wholesale trade with 32 (15%), and agriculture with 27 (12%) incidents. Fuel-powered forklifts caused 29% of all incidents, while autos/trucks/buses were responsible for 26%. The number of forklift incidents in fruit packing and cold storage companies declined significantly from 1994 through 2007 (Spearman's rho = 0.6659, p < 0.01). While this study used multiple medical records from workers’ compensation claims to identify CO poisoning, a surveillance system that lacks extensive medical records may rely principally on carboxyhemoglobin (COHb) tests. This study demonstrated that 71% of the identified workers’ compensation claims had associated COHb tests. The recurrence and timing of CO poisoning as well as control of the CO-generating source were determined. Approximately 8% of all work sites had recurring CO poisoning incidents. Two percent experienced a recurrent incident within 16 days of the initial incident, and 6% experienced a recurrent incident between 16 days and 3 years after the initial incident. Sixty-seven percent of claimants exposed to CO were not in direct control of the CO-generating source; this has implications for CO prevention and underscores the need for all employees to be trained on CO hazards.