Nikkei Asia reported that one of the most important factories in Apple's production line suffered gas contamination.

The contamination occurred at TSMC's "Fab 18" plant, said to be the company's most advanced chip manufacturing facility. As the only company that supplies chips to Apple, TSMC's problems could affect millions of dollars of hardware.

Indeed, Nikkei Asia sources have revealed that all processors for upcoming Mac and iPhone devices are being produced at the troubled plant. This obviously means not only the yet-to-be-announced iPhone 13, but is also likely to cover laptops expected to feature the rumored Apple M2 and M1X chips, possibly including the MacBook Pro 2021.

"Some of TSMC's production lines in the Southern Taiwan Science Park received certain gases from suppliers that are believed to be contaminated," TSMC told the site. These were immediately replaced with other gas supplies."

While the company said that an assessment is underway to ensure that product quality is not affected, early indications are that production should not be significantly affected. TSMC said that the contamination does not appear to have had a "significant impact on operations," and unnamed sources at Nikkei Asia corroborated this, stating that chip production has only taken a limited hit.

Any worse would have been extremely bad news for Apple. The contamination was reportedly discovered Thursday night, just one day after the company warned investors about potential supply problems due to the ongoing chip shortage that has affected everything from PS5 restocking to car production. [Apple CFO Luca Maestri warned investors during the company's Q3 2021 earnings call that "supply constraints in the September quarter are expected to exceed those in the June quarter. This constraint will primarily affect the iPhone and iPad."

Given that he was still predicting "very strong double-digit YoY sales growth in the September quarter," this may just be a case of expectations getting out of control, lest anything but phenomenal growth come off as disappointing.

So far, Apple has largely avoided the worst effects of the global chip shortage. Even when warning of potential trouble, CEO Tim Cook was keen to point out that the supply constraints were primarily in "legacy nodes" rather than Apple's own silicon.

However, the story of the gas contamination at the TSMC plant is a timely reminder that even having your own proprietary production line does not exempt you from unexpected problems. Thankfully, the problem appears to be minor enough not to affect the iPhone 13, which is rumored to be announced in September, but it may serve as a reminder of how dependent Apple is on just one factory.