BEI's in the Occupational Exposure Evaluation to Chemicals

摘要

The technological development usually reduces chemical concentration in work environment. Simultaneously we meet growing number of low or even trace concentration of extremely dangerous chemicals like carcinogens, mutagens and teratogens. When we found larger quantity of different chemicals in air in various concentrations reliable measurement and analytical process could be difficult. Even using advanced analytical methods and procedures doesn't guarantee reliable results. Generally problems may be caused in two ways: collecting samples techniques and analytical procedures. Two techniques are commonly used for collecting the harmful chemical samples: bag air samples (like Tedlar) or vapor passive dosimetry badges. Both could be analyzed and then the concentration could be calculated in a period of time from the moment the exposure and sample collection took place. Both type samples frequently are sensitive for external factors like other chemicals concentration in the air, temperature, luminance or UV radiation as examples only. Analytical procedures that are performed in the laboratories could eliminate some errors but very rarely most of them, especially when higher number of chemicals has been identified. In described situation the classic methods of the evaluation of worker exposure are not sufficient and may result significant errors in estimation of health effect of the exposure. The commonly accepted procedures of monitoring harmful chemicals in occupational environment focuses on the measurement of the chemical concentration in the air and is usually performed as the series of samples collections. In the result we could obtain the average concentration level. The described procedure is accepted and effective for the workplaces of stable or repetitive operation scheme but is unaccepted when the operation scheme is accidental. The alternative for the classic monitoring method seems to be BEI (Biological Exposure Indicator) monitoring. We could find a lot of examples of positive results of BEI's implementation to the monitoring of human exposure (Kneip 1988, Boogard 1995 and 1996). The goal of this study is to verify and validate possibilities of implementation of BEI's in the assessment of occupational exposure to aromatic hydrocarbons - BTX group in the multiple and different levels concentration of other chemicals. Benzene, well known BTX representative is listed as carcinogen and mutagen factor. Other BTX hydrocarbons have not been listed as human carcinogens, however all their harmful health effects are not definitively examined epidemiologicaly, and their late effects are really difficult to discover. The precise and reliable assessment of exposure to BTX is critically important in this context. The measurement of the BTX concentration in the air doesn't cover the dermal exposure health effects neither the possible ingestion that is common because of frequently meet poor hygienic conditions and custom at the workplaces associated with the low risk perception among workers.