Progress in the automatic detection of water contaminants

The new devices use ultraviolet LED as light source that detects contaminant substances thanks to a fluorescence method. This can result in many benefits compared to the current systems due to the development of faster, robust and affordable detection systems. These new devices will be useful for the search of potential dangerous substances present in continental waters, all this according to researchers of the Telecommunication School of the Universidad Politécnica de Madrid (UPM), who are currently studying its viability.

The demand for clean continental waters by European societies and governments is increasing. Thanks to the progress of technological measurement, many contaminants parameters are being measured on rivers and reservoirs (pH, conductivity, oxygen, etc) in order to establish their water quality.

However, there are some contaminants that can be found occasionally (usually by accident) and whose direct identification can be helpful since indirect detection is complex and inexact. On the other hand, rushing contaminants detections are primordial to avoid big mistakes.

Particularly, hydrocarbons are a type of contaminant that should not be present in contaminants water because it can alter dramatically wildlife when a spillage occurs in such water, not forgetting also its removal high cost. The fluorescence light method is non invasive and can help to detect contaminant substances. This method when used in water environment can help detect and identify hydrocarbons.

There are other researchers working in this matter, but are more focused on the marine environment and they also use powerful lasers as light sources. Once the samples are collected they are carried to a lab for their identification, but the time factor is very important and can affect this laser method.

Therefore, researchers launched a study of the light sources available today in order to develop a quick, robust and affordable system. This study discarded some lights used in labs such as xenon because are expensive and need monochromators. The study that is focused on LED light has advantages such as its small device size, quick response and the ability to transmit pulsed light.

These devices are improving faster on the wavelength comparing to the relatively high frequencies. Therefore, research is needed for the viability when working in bad weather conditions, humidity and different temperatures.

The researchers of this study also reveal the viability of obtaining predictable patterns of common fluorescence hydrocarbons that are susceptible of being contaminants (diesel and petrol in different variants or automotive lubricating oil). These patterns can be found thought algorithms. The obtained results confirm why this technique should continue in order to detect contaminants in different waters.