With the increasing interest in green chemistry and sustainability, analytical chemists are developing new methods and reexamining existing methods with a new emphasis on sustainability and environmental impact. Since the publication of the principles of green chemistry in the 1990s and the principles of green analytical chemistry in the 2000s, several scoring systems for evaluating the greenness or sustainability of analytical methods have been developed. In this column, we will examine three widely used scoring methods: Red, green blue (RGB), the analytical greenness metric (AGREE), and the analytical method greenness score (AMGS) with comments on how they all apply to gas chromatography (GC). We will see that classical GC, which has roots in the origins of the environmental movement, has been and remains among the greenest of analytical techniques.
