Quality problems in determination of organic compounds in environmental samples, such as PAHs and PCBs

The literature shows that most interlaboratory comparisons deal with determination of inorganic compounds or physico-chemical parameters. The determination of organic compounds, particularly in environmental samples, is still a challenging analytical problem, which is why there are few interlaboratory comparisons on this subject.The amount and the quality of information obtained from interlaboratory comparisons depend on both their organizer (who selects and prepares material for investigation, and provides statistics based on the results of measurements) and participants (who carry out measurements, determine the validation parameters of the relevant analytical procedure, and publish the results of analyses).We discuss the difficulties in determining organic compounds on the basis of our own investigations on polyaromatic hydrocarbons and polychlorinated biphenyls in environmental samples. We present means of overcoming these difficulties as conclusions emerging from the results of interlaboratory comparisons.