A Department of Defence statement released on Tuesday evening said that “as measurement techniques and test equipment continually improve routine maintenance” had detected strontium chromate inside the aircraft’s environmental control system.
“Subsequent cleaning of the fleet has been carried out and the aircraft will return to service throughout August,” the statement reads.
“Results from laboratory tests thus far do not indicate any concerning levels of chromate or cadmium being detected in aircrew.”
According to Wikipedia strontium chromate is used as “an anti-corrosive primer for zinc, magnesium, aluminium, and alloys used in aircraft manufacture”.
The US National Library of Medicine’s PubChem website notes that: “Strontium chromate primarily affects the lungs causing shortness of breath, bronchitis, pneumonia and asthma but can also affect the gastrointestinal tract, liver, kidneys and immune system. This substance is a known human carcinogen and is associated with an increased risk of developing lung cancer and cancer of the sinonasal cavity.”
The King Air 350 is operated by RAAF Townsville-based 38 Squadron as a light transport and by East Sale-based 32 Squadron for air combat officer training.