At the beginning of the process, a 100 milliliter water sample is concentrated with SPE (Solid Phase Extraction), and subsequently the organic substances are eluted on the HPLC (High Performance Liquid Chromatography) column using a gradient with methanol. Detection takes place with a UV/DAD detector. Together with the supplier, Het Waterlaboratorium has adapted the original laboratory system in such a way that in the case of an event, for example decreasing water quality, an SMS is automatically sent to the person on duty at Het Waterlaboratorium, who is responsible for responding to urgent situations. This person can then remotely determine whether the system has functioned correctly.
For the data analysis, Het Waterlaboratorium uses raw data that comes directly from the detector (see figure 1). The data (about 2.7 million data points) are analyzed using software, developed by Het Waterlaboratorium in the R language. The software compares the current measurement with previous measurements. If the “profile” of the measured water changes significantly compared to these previous measurements (figure 2), an alarm is immediately triggered.
In this case, an automatic sampling carousel is operational that takes a sample directly and which is then sent to Het Waterlaboratorium for additional analysis. The question is then answered whether the changed profile that caused the alarm can be linked to a known or unknown substance. The most modern and advanced equipment and methods are used for this. See also the text Emerging substances on how we do this.
With our special equipment and systems, we can automatically detect suspicious situations in the water and, based on this, take direct targeted action to prevent the quality of drinking water from being endangered.