Publication Abstract

Project ME4117 – Development and Improvement of Analytical Methods for Marine Monitoring. 3.3b - Development of analytical methods for monitoring organophosphorus flame retardants and plasticisers in marine biota samples

Project ME4117 – Development and Improvement of Analytical Methods for Marine Monitoring. 3.3b - Development of analytical methods for monitoring organophosphorus flame retardants and plasticisers in marine biota samples

S. Losada*, J. L. Barber*, A. Papachlimitzou*, S. Morris* and P. Bersuder*

Organophosphorus flame retardants (OPFRs) are compounds with a wide range of uses and their application includes use in anti-foaming agents, hydraulic fluids and in paints.  Their main use is as flame retardants and as plasticizers.  For this reason, they have the potential to be present in the environment.  Due to the banning of the brominated flame retardants, polybrominated diphenyl ethers, the interest in the occurrence, behavior and fate of OPFRs has increased in recent times and this has been reflected in the increasing number of peer-reviewed publications.  Some of these publications have reported OPFRs in many environmental compartments such as within the atmosphere and in biota.  There is a clear need for environmental surveillance and monitoring to be undertaken to describe their distribution and assess their potential impact.

In the study reported here, a total of twenty one OPFR and plasticizer compounds were selected based in previous information concerning their commercial use, persistence and bioaccumulation properties.  A review of the published material has been conducted in order to compile this information as well as a review of methods of analysis for the measurement of these compounds. Based on the information, method development work was been carried out at the Cefas laboratory with the objective of evaluating different approaches and selecting an appropriate technique to adopt in-house.  The method of choice involved gas chromatography mass spectrometric detection (GC-MS). Injection conditions, injection port liners, source temperatures and voltages were optimized for the analysis of the target compounds. Since OPFRs and plasticisers have a tendency to fragment to low molecular weight product ions thus making the selection of specific transition ions difficult, the use of a triple quadrupole mass spectrometer would not permit selective analysis.  Hence, a method using selective ion monitoring (SIM) was developed.  Extraction conditions using the automated SpeedExtractor™ were studied to select the most appropriate solvent to recover all the compounds. However, some compounds with the lowest molecular weights were not quantitatively recovered during this process. This was most likely due volatility issues.  For extract clean up, several options were investigated; these included gel permeation chromatography (GPC), destructive clean up and solid phase extraction.  Results of these tests showed the necessity of two clean up steps (GPC and a column clean up with an amino sorbent) prior to their analysis by GC-MS.  However, it TEHP was lost during the GPC clean up step.

Although the extracts obtained were sufficiently clean following the clean up stages, validation studies showed that the developed method developed did not fully meet desired quality standards for all OPFRs under investigation. This was mainly due to poor recoveries.  Further investigations are required focusing on the optimization of the SPE component of the sample preparation procedure. Also, contamination was found to be a main problem during the sample treatment, making difficult the quantification of some compounds (TCPP, TPP, EHDPP and TIPPP).  Contamination was suspected to have been derived from plastic and Teflon components of the SpeedExtractor, GPC and SPE cartridges applied in the studies. Thus, careful removal of the background levels of these OPFRS and plasticisers is necessary for the accurate determination of environmental levels.

S. Losada*, J. L. Barber*, A. Papachlimitzou*, S. Morris* and P. Bersuder*

Cefas Technical Report