Medical surveillance of workers exposed to chloroplatinates

Medical surveillance is one component of an occupational health programme to protect and maintain the health of all employees at the given workplace who are at risk of developing adverse health effects resulting from exposure to workplace hazards.

Workers within PGM industries – most notably those exposed to complex halogenated platinum salts (CHPS) – can develop platinum salt sensitivity (PSS) and appropriate medical surveillance of workers at risk of PSS should be routinely conducted.

It is important to bear in mind that, in the refining of platinum and handling of platinum compounds, there may be exposure to hazards other than CHPS (e.g., acid mists, chlorine, ammonia, hydrazine, formaldehyde and other chemical agents). Many of these may cause adverse health effects or aggravate pre-existing conditions.

The principal tools for surveillance, investigation and diagnosis of PSS include questionnaires for assessing clinical symptoms, objective tests of immunological response (IgE) to confirm sensitisation to CHPS, and respiratory function tests to confirm or exclude occupational asthma.

Any medical surveillance programme specific to a particular facility should be developed in consultation with appropriate medical and occupational health professionals. Considerable clinical skill and judgment are required in implementing such programmes and consultation with properly trained personnel is critical. Issues such as the invasiveness, safety, sensitivity, and accuracy of testing procedures in compliance with the constantly evolving legal conditions and requirements in the respective jurisdiction must be considered carefully, as should the rights of the workers.

A number of tests that have been used to investigate PSS — including specific inhalation challenge (SIC) with chloroplatinate salts, and tests for measurement of non-specific bronchial hyperresponsiveness (NSBHR) — will not be routinely available for use by most occupational physicians responsible for medical surveillance, as such tests are usually available only in specialised research laboratories.

A medical surveillance programme should include a preplacement examination followed by periodic assessments and examination on termination of employment. Periodic assessments may be conducted routinely (e.g., semi-annually, yearly, etc.) or under special circumstances (e.g., when a worker is moved between workplaces with different exposure levels, or if workers suspect a causal link between illness and their workplace exposures).

While biological monitoring for systemic absorption of Pt has been conducted in workers, no predictive correlation has been established with respect to Pt found in biological media and risk of sensitisation. Some regulatory bodies have proposed the use of platinum urinary levels as potential indicators of workplace exposures, but they have cautioned that such levels are not necessarily related to health risks. Requirements for biological monitoring vary across jurisdictions and consultation with appropriate regulatory authorities is recommended.

Additional information and detail on medical surveillance options for workers exposed to complex halogenated platinum salts (CHPS) is provided within the IPA Guidance Document: Safe Use of Platinum Group Metals in the Workplace".

The usage of the methods and testing procedures described here and within the IPA guidance document remains under the sole responsibility of the user. The invasiveness, safety, sensitivity, and accuracy of testing procedures in compliance with the legal requirements in the respective jurisdictions must be carefully verified in each individual case in advance.