In medical devices, ETO gas sterilization (ethylene oxide sterilization) treated 68% of heat-sensitive devices worldwide, including endoscopes (lumens up to 3 m long) and heart stents (1.5-5mm diameter). According to Johnson & Johnson Medical’s statistics in 2023, its Suzhou factory sterilized 240 million orthopedic implants annually by ETO technology, the qualification rate of sterilization reached up to 99.9999%, and the material loss cost dropped to 0.5 yuan/piece (3.2 yuan/piece for traditional steam sterilization). For artificial joints with precision sensors (surface roughness Ra≤0.8μm), the ETO sterilization treatment cycle at 55℃ is cut down to 6 hours, compared to 24 hours for gamma-ray sterilization, and the annual production capacity of the instrument is increased by 38%. The FDA says that ETO has a ≤2% effect on tensile strength of silicone catheters (electron beam in the control group decreases by 9%), thus making it the optimal option for indenture catheter sterilization.
The pharmaceutical packaging industry relies on the ETO gas sterilization treatment of sterile syringes (more than 50 billion units a year), whose gas penetration capacity can penetrate a 0.3mm thick multilayer composite film at 30% humidity. Ever since Pfizer applied this technology, the pre-poked syringes’ microbiological challenge test pass rate increased from 98.7% to 99.999%, and the contamination complaint rate decreased by 83%. For temperature-sensitive mRNA vaccine vials (cold chain requirement -70 ° C), ETO sterilization is performed at 40 ° C, which conserves 92% of cold chain energy consumption compared to conventional radiation sterilization. Roche validation data in 2022 showed that the sealing deviation of the corkplug after ETO treatment was less than 0.02mm³/s, and therefore the vaccine validity was prolonged to 24 months (the original process was 18 months).
In the disposable protective material production process, 1.2 million N95 masks per day were processed by ETO gas sterilization at the peak of the COVID-19 pandemic. In 2020, Wuhan Leishenshan Hospital utilized this technology to shorten the sterilization cycle of protective clothing from the traditional 7 days to 36 hours, and the microbial kill log value was as high as 6.0 (national standard requirements ≥4.0). 3M tests showed that the filtration efficiency of FFP2 masks after ETO treatment decreased by only 0.3% (99.2% of the initial value), while the charge attenuation of melt-blown fabric caused by high temperature sterilization lowered the efficiency by 4.7%. According to OSHA statistics, production cost of ETO sterilization protective devices is $0.12 / device less than that of electron beam sterilization protective devices, and cost savings amount to over $230 million annually.
Electronic medical device manufacturers prefer ETO gas sterilization for devices with precision circuits. A 32-bit Medtronic microcontroller (4 x 4mm in dimensions) for cardiac pacemakers was sterilized with ETO, and the electrostatic discharge sensitivity was improved from HBM 500V to 2000V, and the failure rate was reduced from 0.7% to 0.03%. During the production of smart insulin pump, the effect of ETO on antenna impedance of the Bluetooth module is less than 1.2Ω (8.5Ω is gamma ray induced deviation), which increases the communication stability of the device by 89%. According to Boston Scientific’s 2023 annual finance report, 83% of its annual production of vascular intervention devices (approximately 120 million pieces) used the ETO production line and the rate of quality cost reduced by 2.4 percentage points from previous year.
Evidently in the industry for laboratory consumables sterilization, the market share of eto gas sterilization was 55%, used dominantly for 50ml centrifuge tube sterilization (thickness of wall = 0.8mm) and 0.1-10μL pipette tips. Once this technology was utilized by Thermo Fisher, the rate of sterilization batch qualification of cell culture dishes increased from 99.1% to 99.98%, while the unit cost was reduced to 0.08 yuan/piece (64% reduction versus autoclaving). According to the PCR plate 384 holes (aperture 1.2mm) sterilization requirements, ETO achieved 100% penetration at 45℃, and the residue amount of DNA enzyme was < 0.01IU/plate (0.15IU/plate after radiation sterilization), which can ensure the accuracy of gene detection.
The food packaging employed ETO gas sterilization to treat infant food composite membrane (thickness of 120μm), which extended the shelf life from 9 months to 15 months and reduced the failure rate from 0.12% to 0.003%. The equipment uses double-cycle analysis, therefore the amount of remaining ethylene oxide is less than 1ppm (national requirement ≤20ppm), and the treatment price is 0.4 yuan /m² lower than for hydrogen peroxide plasma sterilization. In 2023, Danone Group testified that when ETO sterilized aluminum foil sealing film was being cooked at 121℃, the sealing strength retention rate was 98.7% (89.2% for control group epoxide sterilization).
In phytosanitary treatment, egg mortality rate of imported flower balls (3-8cm in diameter) via ETO gas sterilization was 99.99%. Following the application of this method by Royal Netherlands Floriculture, the treatment time of quarantine for lily balls reduced from 21 days to 72 hours and survival improved from 82% to 97%. Usda statistics show that the efficiency of inactivation against nematode of pine packages fumigated with ETO is 37% higher than by bromomethane fumigation, and the bending strength of wood fell by only 0.8% (while bromomethane fell 4.5%). In 2022, Ming Dynasty silk fabric (thickness: 0.15mm) was introduced into ETO treatment in insect control at the Palace Museum, and the colonies diminished completely to <10²CFU/g from the original 10⁶CFU/g, while ΔE value increased by only 0.3 (international standard of preservation for cultural relics: ΔE≤1.5).
