Uncertainties in risk analysis and modern approaches to their reduction

The article analyzes the most common approaches to the risk assessment procedure and focuses on uncertainties at each stage of risk analysis. These uncertainties not only impede risk analysis but are also able to skew its results. The greatest impact on reliability of final risk assessments is caused by uncertainties associated with assessment of exposure, in particular, with establishing toxicological parameters in experiments and their extrapolation onto assessed population groups. An effect of a selected toxicant on a test animal sample is identified with an expected negative effect produced by it on a real human population. In addition, in laboratory experiments, in contrast to natural conditions, a population is affected only by controlled factors in small amounts. Next, the article describes some uncertainties that arise at the stage of assessing the dose-effect relationship; in studies aimed at reducing uncertainties at this stage, it is almost impossible to detect a link between pollution and diseases not declared for research purposes. The problem of toxicological assessment of mixtures is described; the article highlights that at the moment there are no data on effects produced by most known mixtures on human health or any data on possible interactions between different chemicals either. The concept of exposome is described, which is an analysis of impacts of all environmental factors on an individual throughout his lifetime. It is concluded that the existing concepts of risk assessment are applicable mainly for comparing hypothetical benefits and hypothetical damage at the population level. Given that, it seems quite relevant to develop such a concept of risk assessment that can be additionally used in planning preventive measures aimed at reducing morbidity and mortality and increasing life expectancy. At the same time, this concept should include a comprehensive assessment of mixtures affecting the body, considering the influence of natural and climatic conditions and non-specific reactions of the body.