Sampling and Analytical Method Performance for Platinum Monitoring in an Occupational Hygiene Context

The objective of this project was to develop a comprehensive protocol detailing sampling and analytical methods that together will achieve the lowest practical limits-of-detection for occupational/industrial hygiene monitoring of soluble platinum.

After a review of the literature and discussions with industry experts, the following samplers were considered for further study as meeting most of a critical set of selection criteria:

1) An IOM operated at a flow rate of 2 L/min (the reference sampler)
       Collects the Inhalable Fraction of PM
2) A 37mm closed-face cassette (CFC) operated at 4-5 L/min
       Collects a pseudo-Inhalable Fraction of PM
3) An SKC Parallel Particle Impactor (PPI) operated at 8 L/min
       Collects the Respirable Fraction of PM
4) An SKC PPI operated at 2 L/min
       Collects the Respirable Fraction of PM

From the outcomes of laboratory blank and spike recovery experiments using chloroplatinates, more extensive field studies were conducted at a PGM facility in the USA with both Teflon and mixed cellulose ester (MCE) media and lessor effort with PVC media, in combination with the selected samplers.

The 'soluble platinum' extraction fluid, extraction time and agitation, extractant volume and a number of operational parameters, such as cleaning and media pretreatment, were characterised.

The studies identified the IOM (2 L/min - inhalable) and PPI (8 L/min - respirable) samplers configured with MCE filters as the optimum sampler/media configuration.

Field studies were then carried out at six facilities on three continents by IPA scientists and healthcare professionals, in order to test the efficacy of the laboratory and single facility trials and to broaden the industry experience with the new methodologies. Where comparable, these extended field trials confirmed the original studies.

Following the above program, an IPA workplace sampling procedure was recommended, which has since been incorporated into the IPA guidance 'Safe use of platinum group metals in the workplace' and is being widely adopted by the platinum industry.

This research programme is being written up for publication in the peer-reviewed scientific literature.