A water testing lab that runs analysis for VOCs, IOCs and SOCs would be able to do this. In the USA, it cost about $600 per sample to do a basic chemical contaminant analysis. There are very specific sampling, handling and preservation requirements that need to be carefully followed. Check with your local laboratory. Make sure that the laboratory is "ELAP" certified. In order for the lab to be certified, they need a very strict QA/QC program including QA analysis of routine "unknown" samples.
If the basic analysis shows some "detects" of some chemical "families", then you probably will need to do more testing to verify the detect and narrow down the possible source of contamination.
In laboratory analysis language, any material in a matrix is considered a "contaminant". The reported quantitative results will need to be compared to the results reported for a "clean" sample.