How to evaluate methods used in chemical laboratories in terms of the total chemical risk? – a ChlorTox Scale

Reliable assessment of the health and environmental risk associated with the use of chemicals is critical to objectively evaluate the greenness and whiteness of an analytical method. An objective and useful way of risk assessment should take into account all the relevant properties of used substances, their actual amounts needed for application of the method, and quantify the assessment result using a standardized unit. This article presents a relatively simple approach to meet the above requirements, which we call the Chloroform-oriented Toxicity Estimation Scale (ChlorTox Scale). The risk posed by a given substance is expressed by the ChlorTox value, and the sum of the values obtained for all reagents is the overall risk posed by the method (Total ChlorTox). The ChlorTox value is calculated by comparing the hazards for the substance being assessed to the standard – chloroform, using the approach selected by the user as optimal, taking into account the amount of a pure substance needed for single analysis. The ChlorTox unit is the equivalent mass of chloroform which reflects the estimated degree of predicted risk. This tool can be used for risk assessment in laboratories of various profiles.