Uncertainty in environmental analysis: theory and laboratory studies

In this paper, theoretical and practical aspects of uncertainty in environmental laboratory analysis are presented and discussed. A more detailed theory of uncertainty is described, with special emphasis on the factors which contribute to the understanding of this in order to obtain accurate environmental laboratory data analysis. A full discussion is reported relating to approaches used to evaluate uncertainty, particularly the so called "bottom-up" and "top-down" approaches. Relevant aspects of uncertainty related to instrumental analysis and calibration are discussed. Problems arising from linear and non linear calibration and outlier identification and their relationships with uncertainties were also fully examined.