An inventory of marine pollutants

A new method for non-targeted analysis of marine pollutants provides the basis for creating an inventory of persistent pollutants, exemplified by the analysis of dolphin blubber.

When scientists look for pollutants in life that inhabits the seas and oceans, they generally look for a particular group of compounds in a targeted analysis. The obvious limitation with this approach is that other important and toxic pollutants might be overlooked. An alternative method would be a non-targeted analysis to look for everything, a process that has been tested by scientists in the US who have published details in Environmental Science and Technology.

They employed a GC/MS method that uses two columns in series to gain better separation of all the components and which allows sample extracts to be analysed directly. By linking the second GC column to a time-of-flight mass spectrometer, the massive amount of data generated could be processed and used to identify the compounds present by a range of schemes, supported by custom-built software.

The system was tested with blubber of the common dolphin found in the Atlantic ocean and revealed a staggering total of 271 compounds, of which 270 were halogenated, including 54 halogenated natural products, the expected anthropogenic pollutants, and 86 anthropogenic pollutants that are "not routinely targeted in environmental surveys."

As well as creating a marine inventory of pollutants, the work will lead to the inclusion of newly discovered contaminants in targeted analyses in the future which will help to refine toxicological assessments.