Revealing nature's secrets: A chemical forensics approach to decode the information stored in water

When thinking about water quality, many people probably think about individual pesticides or antibiotics that they heard about in the news. The truth is, there are hundreds, likely millions, of chemicals present in most surface water samples. These chemicals might seem like a random assortment of molecules, but they are a chemical record, or a receipt, of all the biological, chemical, and physical processes that are occurring within a system. When people disturb the land, it leaves a chemical signature in the water. When salmon spawn in the rivers, it leaves a chemical signature in the water. Whether processes occur on land or in the water, our surface waters are libraries of chemical information. If we can decode the chemical signatures in a water sample, we can theoretically collect data on anything and everything that occurs upstream. The challenge is decoding the chemical signatures present. This work has implications for understanding human and ecosystem health and provides a glimpse into how nature will respond to climate change.