Philips ignored or suppressed a series of studies that revealed problems with its sleep apnea devices as early as 2016, according to documents filed with a court in the US.

Independent laboratory PSN Labs claimed that the Amsterdam-based electronics giant failed to heed internal warnings about polyester noise cancelling foam used in its ventilators.

PSN Labs also accused the company of failing to notify US health authorities, such as the Food and Drug Administration, of the results of tests carried out by external laboratories.

In 2021 Philips recalled 15 million devices that used polyester foam to dampen the noise after it was found to have degraded during cleaning. More than 1,000 patients in the Netherlands and some 60,000 in the US are suing the company for health problems that they say were caused by the Dreamstation devices.

Some 70 patients in the Netherlands claim they developed cancer as a result of inhaling particles of foam that came loose during cleaning. Philips says independent tests have shown there is no link between the machines and cancer.

The company is suing PSN Labs for mistakes the laboratory allegedly made when Philips commissioned it to carry out a risk assessment of its sleep apnea devices.

“Egregious errors”

Philips says it would have “pursued a different and more focused recall” if PSN had not made “numerous egregious errors” and “greatly overestimated the potential threat to patients”.

But PSN Labs, in its 50-page submission to the court in Pittsburgh, said it had not been shown 14 critical internal reports about the polyester foam, according to a report in NRC. It claimed it had been put under pressure to produce a report that played down the health risks.

The laboratory accused Philips of covering up its mistakes by hiding test results and “selectively” citing reports with favourable outcomes, in order to “minimalise significant risks” and “hide them from the public and regulatory authorities”.