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Combined chemical, physical hazards make exposures harder to calculate.
Nelson-BK; Conover-DL; Lotz-WG
Occup Health Saf 1994 Jun; 63(6):50
Problems associated with the characterization of occupational hazards based on the effect of a single agent or the additive effects of several agents were addressed. The authors supported an approach that considered all hazards to which workers are exposed as a combined risk, rather than estimating risk associated with multiple exposures by adding the adverse effects of individual agents. Several examples were presented supporting the authors' view. A study by NIOSH demonstrated that the additive approach was accurate in predicting adverse developmental outcomes resulting from exposure to chemical and physical agents in only about 50% of the cases. Actual risks were overestimated using this approach in 25% of the cases and underestimated, some dramatically, in the other 25%. In addition, studies have indicated a markedly increased risk of developmental disorders for combined exposures to radiofrequency radiation and 2-methoxyethanol (109864) compared with the risk for exposure to either agent alone. Similar increased risks for hearing loss in humans exposed to both organic solvents and noise have been reported. The authors recommend that risk assessments take into account the interactive effects of combined chemical and physical agent exposures.
Occupational-exposure; Occupational-hazards; Synergism; Organic-solvents; Developmental-disorders; Ethanols; Radiation-exposure; Toxic-effects; Hearing-loss
Issue of Publication
Occupational Health and Safety
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division