Contract manufacturer Viant Medical Inc. will close its sterilization operation in Grand Rapids, Mich., as an investigation continues into air emissions of a carcinogen.
However, a company spokesman said the closure planned for later this year and the ongoing probe are not directly related.
The sterilization chambers at the plant were included in the purchase of the property in 2015, and are only a small part of the business model, said Viant spokesman John Truscott, who is with the Lansing-based public relations firm Truscott Rossman.
"Viant is getting out of the business and has informed customers that they will need to find alternatives," Truscott told Plastics News.
The customers sell catheters and connectors that Viant manufactures. The medical devices can't be sterilized using steam so a flammable gas called ethylene oxide (EtO) is used to fumigate the products in a chamber. Viant will discontinue the process and focus on its core business of medical device manufacturing and assembly, Truscott said.
With estimated sales of $310 million, Viant ranks No. 28 among North American injection molders.
Viant, formerly MedPlast Inc., and the Grand Rapids site's predecessors (Vention and Medtronic) have been using EtO to sterilize medical equipment at the location for 30 years, according to the Michigan Department of Environmental Quality (MDEQ). EtO was regulated as a probable human carcinogen from 1982-2016, when it was classified as a known human carcinogen. MDEQ restricts emissions of the gas when it issues air permits to companies. Viant's permit requires pollution control equipment to remove EtO before emissions are exhausted to the atmosphere.
In July 2017, Viant reported an emission problem to state regulators related to a faulty rubber seal on a part of the sterilization system. The company says the malfunction was corrected within a day of its discovery.
"We immediately stopped operations and repaired the seal. We later received a notice of violation from the MDEQ as a result of that self-reported incident. Since then, we have worked closely with the MDEQ to test and monitor air quality at the plant," Viant says in a letter to residents who live by the facility, including students at Grand Valley State University.
The letter hit households just ahead of a March 6 community meeting organized by MDEQ, which says it continued its investigation after the seal was repaired because "levels of ethylene oxide emissions associated with the facility were found to be higher than expected."
During a November 2018 inspection, MDEQ environmental engineers said they learned cardboard boxes of the medical products needing sterilization are placed on racks in one of five fumigating chambers. Then, EtO is introduced into the chamber to sterilize the products. A vacuum pump then collects the EtO emissions and pulls them to a small scrubber, which vents to a larger scrubber. After the chamber is evacuated of EtO, the racks are removed and taken to aeration cells to ventilate residual EtO, which also vents to the large scrubber.
"Facility personnel stated that elevated levels of ethylene oxide are measured when racks are transported from fumigation chambers to aeration cells," MDEQ reported.