Benzene toxicity and risk assessment, 1972-1992: implications for future regulation.

Abstract

Acute and chronic exposure to benzene vapors poses a number of health hazards to humans. To evaluate the probability that a specific degree of exposure will produce an adverse effect, risk assessment methods must be used. This paper reviews much of the published information and evaluates the various risk assessments for benzene that have been conducted over the past 20 years. There is sufficient evidence that chronic exposure to relatively high concentrations of benzene can produce an increased incidence of acute myelogenous leukemia (AML). Some studies have indicated that benzene may cause other leukemias, but due to the inconsistency of results, the evidence is not conclusive. To predict the leukemogenic risk for humans exposed to much lower doses of benzene than those observed in most epidemiology studies, a model must be used. Although several models could yield plausible results, to date most risk assessments have used the linear-quadratic or conditional logistic models. These appear to be the most appropriate ones for providing the cancer risk for airborne concentrations of 1 ppb to 10 ppm, the range most often observed in the community and workplace. Of the seven major epidemiology studies that have been conducted, there is a consensus that the Pliofilm cohort (rubber workers) is the best one for estimating the cancer potency because it is the only one with good exposure and incidence of disease data. The current EPA, OSHA, and ACGIH cancer potency estimates for benzene are based largely on this cohort. A retrospective exposure assessment and an analysis of the incidence of disease in these workers were completed in 1991. All of these issues are discussed and the implications evaluated in this paper. The range of benzene exposures to which Americans are commonly exposed and the current regulatory criteria are also presented.

Potential Health Effects of Gasoline and Its Constituents: A Review of Current Literature (1990-1997) on Toxicological Data

“…Various papers reporting benzene blood levels in groups occupationally exposed to gasoline indicate that occupational activities are significant determinants of blood benzene concentrations (194)(195)(196)(197). A global evaluation of risks from benzene exposure is reported by Paustenbach et al (198) and Hughes et al (199).…”

Review of new evidence regarding the relationship of gasoline exposure to kidney cancer and leukemia

“…While it is possible that the excesses are related to the benzene content of gasoline, they need further study in the light of actual benzene exposure levels. Also, there are new data relating to the magnitude of the leukemia risk from benzene that need consideration (8).…”

“…At a meeting in Miami, Florida, November [5][6][7][8]1991, on the health effects of gasoline, a panel was formed to evaluate the evidence and express an opinion. Presented at the meeting were four new or updated sets of epidemiological data that dealt with deaths from kidney cancer and leukemia.…”

A hierarchically porous diatomite/silicalite-1 composite for benzene adsorption/desorption fabricated via a facile pre-modification in situ synthesis route

“…Benzene was used as the model organic compound to systematically evaluate the adsorption-desorption performance of the obtained diatomite/silicalite-1 composite. Benzene, a typical VOC, is primarily released from building and decoration materials in indoor environments and leads to massive environmental problems in industrial and domestic settings [41,42]. In this work, the benzene adsorption capacity of the novel synthesized composite was studied.…”