Screening for extractables in additive-manufactured acrylonitrile butadiene styrene orthopedic cast

Abstract The use of additively-manufactured components in medical applications, specifically medical devices (e.g., orthopedic casts), has increased in recent years. Such devices may be fabricated at the point of care using consumer-grade additive manufacturing. Limited studies have been conducted to evaluate the extractable substances of these devices. Chemical characterization by mass spectrometry followed by toxicological risk assessment is one means of evaluating safety of devices. This study was designed to determine the extractables profile of additively-manufactured materials according to filament grade and post-processing method. Feedstock for additive manufacturing were tested as filament and manufactured casts, while the cast from consumer-grade filament (CGF) was post-processed. Samples were extracted using three solvents of varying polarities. Extracts were analyzed by gas chromatography/mass spectrometry (GC/MS) and liquid chromatography mass spectrometry (LC/MS) techniques. In GC/MS analysis, isopropanol extracts generated fewer compound identifications for USP Class VI filament (USPF)-based casts (3) compared with the respective filament (17) while hexane generated the most compound identifications for the finished cast manufactured from CGF. CGF was found to have the highest number of nonvolatile extractables for isopropanol (15) and hexane (34) by positive ion LC/MS. Additionally, CGF produced more non-polar extractables in hexane than the USPF. One of the compounds that were identified in both GC/MS and LC/MS is a potential genotoxicant, styrene acrylonitrile (SAN) trimer toxicant, and known polymer byproduct in quantities ranging from 19 to 270 μg g−1. Overall these results suggested that the extractables profile was affected by the filament material, printing procedure, and post-processing method.