Risk assessment of combined exposure to environmental biological and chemical factors on man

The paper provides the results of experimental risk assessment of exposure to a biological factor combined with a chemical factor, which present with the protein-bearing dust and sulfur dioxide. The regularities and specific features of the functioning of the body's physiological systems have been revealed in the development of responses to combined exposure to biological and chemical factors, which show that the response may take three basic paths: sensitization, allergopathy, and toxic allergopathy. The essentials of the methodology evaluating and predicting the nature of the biological effects of a response in the experimental study of combined exposure to biological and chemical factors of the nature have been developed.     

Cumulative risk assessment for combined health effects from chemical and nonchemical stressors

Cumulative risk assessment is a science policy tool for organizing and analyzing information to examine, characterize, and possibly quantify combined threats from multiple environmental stressors. We briefly survey the state of the art regarding cumulative risk assessment, emphasizing challenges and complexities of moving beyond the current focus on chemical mixtures to incorporate nonchemical stressors, such as poverty and discrimination, into the assessment paradigm. Theoretical frameworks for integrating nonchemical stressors into cumulative risk assessments are discussed, the impact of geospatial issues on interpreting results of statistical analyses is described, and four assessment methods are used to illustrate the diversity of current approaches. Prospects for future progress depend on adequate research support as well as development and verification of appropriate analytic frameworks.     

长隧道理化因素变化及其对作业人员的影响研究

目的 探讨铁路特长、长隧道内污染物和疾病的发生发展规律,为国内特长、长隧道卫生标准的制定提供科学依据。方法 对某长隧道作业环境进行调查,同时对72名隧道作业工人和59名对照进行健康监护。结果 隧道内空气粉尘、噪声超过国家卫生标准,且粉尘、噪声、NOx、SO2污染日趋严重,氧含量逐年升高,健康危害以听力损害最严重,其次为心电图异常逐年上升,肺纹理改变逐年加重,红细胞、白细胞、淋巴细胞、中性粒细胞计数逐年下降。结论 某铁路长隧道对作业人员的危害表现为慢性职业危害。     

Experimental study of the combined biological and chemical factors

This experimental study deals with the immunobiochemical mechanisms of the body's response to the combined influence of biological and chemical factors. The response of guinea pigs has been established to have its peculiarities, depending on the succession of administration of the studied factors with the development of allergic or toxicoallergic reactions. A chemical factor followed by a biological factor has the highest destabilizing effect on the functioning of the body's physiological systems.     

The scientific assessment of combined effects of risk factors: different approaches in experimental biosciences and epidemiology

The analysis of combined effects of substances or risk factors has been a subject to science for more than a century. With different goals, combined effect analysis was addressed in almost all experimental biosciences. The major theoretical foundation can be traced back to two distinct origins. First, to the work by the pharmacologist Loewe on the concept of concentration additivity and second to the biometrician Bliss and the concept of independent action. In the search for a general solution and a unified terminology the interrelations of the concepts have extensively been studied and experimental findings reviewed. Meanwhile there seems to be consensus in experimental sciences that each concept has its role in predicting combined effect of agents and both are used for hazard und risk management. In contrast, epidemiologists describe combined effects mainly in terms of interactions in regression models. Although this approach started from a probabilistic model equivalent to the concept of independent action this origin is rarely acknowledged and effect summation is usually the preferred concept nowadays. Obscure biological meaning, the scale dependency of interaction terms as well as unavoidable residual confounding are taken as reasons why no new insights in combined effect analysis are likely to occur from epidemiology. In this paper we sketch the history of ideas and the state of the arts in combined effect analysis. We point to differences and common grounds in experimental biosciences and epidemiology.