In 1972, researchers at Eawag started to apply advanced chromatographic techniques for the deter­mination of individual organic contaminants in the aquatic enmvironment. In this lecture, I will present a personal review on highlights that occurred in the discipline of analytically oriented environ­mental chemistry. In particular, I will emphasize the key role of the methodological progress of the quanti­tative determination of traces of individual organic contaminants, so-called micropollutants. A first pivotal development was in the early 1970’s the introduction the direct coupling of gas chro­matography to mass spectrometry (GC/MS). The Eawag research groups profited substantially from the co-operation with Professor Kurt Grob, who enabled them to apply high-resolution GC with glass capillaries. Target chemicals were several types of semivolatile and volatile environmental pollutants such as petroleum hydrocarbons, polycyclic aromatic hydrocarbons, chlorinated solvents (e.g. tetra­chloroethylene) and phenolic compounds. A broad range of environmental compartments were studied encompassing recent lake sediments, surface waters, groundwaters, airborne particulates and rain water.

In the early 1980’s the focus shifted to less volatile and more polar contaminants with a particular emphasis on constituents of household detergents including surfactants, complexing agents and fluorescent whiteners. In particular, nonylphenolic compounds were studied that derived from nonyl­phenol polyethoxylates used as nonionic surfactants. Additional analytes were sulfomnated aromatic substances with different inputs to the aquatic environment. Liquid chromatography with fluorescence detec­tion was a pivotal method. Besides wastewaters and natural waters also sewage sludges were analyzed. The environmental desaster of the so-called Sandoz chemical spill at Schweizerhalle in 1986 had a significant impact on environmental research activities at Eawag including well supported inter­national collaboration.

The application of liquid chromatography directly coupled to mass spectrometry (LC/MS) starting in the early 1990’s enabled investigations of more polar conta­minants such as pharmaceuticals and polar plant protection chemicals including environmentally relevant meta­bolites. The extremely persistent per- and polyfluorinated alkyl substances (PFAS) were added as analytes particularly studying their occurrence in sewage sludges. The very widely distributed PFAS are currently in the focus of monitoring studies in Switzerland. In addition, ongoing developments such as using LC coupled to high-resolution MS for suspects and non-target screening will be briefly mentioned.

This presentation is a modified and extended version of the lecture presented by Walter Giger at the International Conference of Chemistry and the Environment (ICCE 2023) in Venice. That talk was given on the occasion of receiving the Lifetime Achievement Award 2023 by the Division of Chemistry and the Environment of the European Chemical Society.