Chronic pulmonary function loss from exposure to toluene diisocyanate

Abstract

In 1972 a total of 112 workers exposed to toluene diisocyanate (TDI) were examined for acute pulmonary function changes during a work shift on the first day of the working week. A dose-response relationship was demonstrated for the acute effects of TDI in this population. The cohort was restudied in 1974 to determine whether there was excessive loss of pulmonary function, and if so, whether there was an exposure level below which this did not occur. The original cohort was reduced to 63 workers available for re-survey of which 57 could be assigned reliable personal exposure levels for the two-year study period. Pulmonary function measurements were made again before and after work on the first day of the working week. A total of 132 environmental samples were collected on this and previous occasions during the study period. The 57 workers were divided into three exposure subgroups (≤ 0·0015; 0·0020 - 0·0030; ≥ 0·0035 ppm). Using the FEV1·0 as a measure of response, a dose-response relationship was observed. Only those in the lowest exposure subgroup showed normal two-year declines. The FEV1·0 of those in the highest exposure group fell 206 ml in two years (103 ml/year) which exceeds the expected value by three- to fourfold. The decrement of FEV1·0 in the middle exposure group was borderline (42 ml/year). These differences in FEV1·0 by exposure subgroup were not explained by age, months employed, smoking habits, or variables related to lung size. A significant association (r = 0·35, p < 0·005) between acute and chronic decrement in FEV1·0 was shown again. We conclude that chronic occupational exposure to TDI at 0·003 ppm or higher is unsafe.

Respiratory symptoms and pulmonary function of workers exposed to cork dust, toluene diisocyanate and conidia.

“…This is the first time that the aforementioned risk factor has been assessed as a possibleproducer of asthma in the cork industry. Three arguments in favor of this association were found: (i) the association of asthma only with exposure to TDI (specificity); (ii) the strength of the association (OR 3.22, 95 % CI 2.87-3.61); and (iii) coherence with previous studies on isocyanates (7)(8)(9)(38)(39)(40). We believe this finding contributes to the understanding of suberosis, since exposure to cork dust or conidia was not significantly associated with asthma in this study.…”

“…Despite the known risk of asthma with exposure to TDI (5)(6)(7)(8)(9)(10)(11), its etiologic role in suberosis has not been considered until now. Furthermore, occupational exposure to cork dust in grinding and polishing has not been studied as a possible risk factor for other respiratory diseases.…”

Industrial hygiene characterization of urea formaldehyde and polyurethane foam insulation.

“…However, at least several hundred workers were potentially exposed to polyurethane foam components provided by just one distributor. Although there are several reports related to occupational exposure to isocyanates used in the production of polyurethane foam (3)(4)(5)(6)(7)(8)(9), no report was found identifying worker exposure to total polyurethane foam production systems; therefore, polyurethane was placed in Category A.…”

Health hazard evaluation report: HETA-94-0124-2470, Whirlpool, Corp., Evansville, Indiana.

“…asymptomatic permanent loss of lung volumes. 23,24 Certain individuals may develop isocyanate sensitization, which is usually manifested as a debilitating asthma-like illness caused by very low, even unmeasurable isocyanate concentrations. 10 Other adverse health effects in humans due to isocyanate exposure are skin and eye irritation, 25,26 and skin hypersensitivity.…”