EO residuals/VHP residuals
Ethylene oxide (EO) gas sterilization is a dependable and effective method of sterilizing heat and/or moisture sensitive devices. Additionally it provides the following benefits:
- Materials can be prepackaged, then sterilized and maintained sterile until used.
- Ethylene oxide is relatively non-corrosive to plastic, metal, or rubber materials.
- Sterilization parameters may be monitored to ensure effectiveness and to distinguish processed from un-processed materials.
In an effort to insure that levels of Ethylene Oxide (EO) and Ethylene Chlorohydrin (ECH) pose a minimal risk to the patient in normal product use, exposure limits have been set. Established limits by ANSI/AAMI/ISO make analysis of EO residuals mandatory. Nelson Laboratories analyzes for ethylene oxide, ethyl chlorohydrin, and Ethylene Glycol (EG) using state of the art gas chromatographs.
Nelson Laboratories places EO residual samples on test within 24-48 hours. This is contingent upon receipt of a completed sample submission form and extraction specifics form (weekends excluded).
Optional Tests for EO residuals/VHP residuals
Hydrogen peroxide Determination extract & assay USP 28
This test determines the concentration of hydrogen peroxide in solutions. It is also used to determine the amount of residual hydrogen peroxide remaining on materials or devices after hydrogen peroxide sterilization. It is a titration assay that utilizes the oxidation-reduction reaction of hydrogen peroxide and potassium permanganate under acidic conditions.
Hydrogen peroxide Determination assay only USP 28
This test determines the concentration of hydrogen peroxide in solutions. It is also used to determine the amount of residual hydrogen peroxide remaining on materials or devices after hydrogen peroxide sterilization. It is a titration assay that utilizes the oxidation-reduction reaction of hydrogen peroxide and potassium permanganate under acidic conditions.
Prolonged (24 hr-30 days) or permanent use (30+ days): EO & ECH ISO 10993-7 (water extraction) ISO 10993-7
EO & ECH for liquid sample (no extraction) ISO 10993-7
Ethylene glycol (EG) only for liquid sample (no extraction) ISO 10993-7
The EO extraction specifics form is recommended when submitting samples for this study.
Ethylene chlorohydrin (ECH) only for liquid sample (no extraction) ISO 10993-7
The EO extraction specifics form is recommended when submitting samples for this study.
Ethylene oxide (EO) only for liquid sample (no extraction) ISO 10993
The EO extraction specifics form is recommended when submitting samples for this study.
EO, ECH & EG for liquid sample (no extraction) ISO 10993-7
Liquid samples either go unprocessed before analysis or may be diluted. Please be sure to specify ALL components of the liquid. It is recommended that a background sample is submitted with liquid samples to insure no interfering compounds present.
SAMPLE HANDLING
Do not freeze samples. Samples should be shipped refrigerated (on ice). It is recommended that samples are packed so that there is no direct contact with ice to avoid the potential for freezing.
The EO extraction specifics form is recommended when submitting samples for this study.
Limited use device (<24hrs) EO, ECH & EG (water extraction), one extraction only ISO 10993-7
Devices in this category have contact with the body for significant periods of time. They are extracted for several days as specified by client or are exhaustively extracted. In either case the sample is extracted in 24 hour increments. They are extracted either fluid path or by immersion with USP purified water and at either body temperature 35-39° or room temperature 20-25°. Exhaustive extractions are analyzed until a subsequent extraction is less than 10% of the first extraction.
EXPOSURE LIMITS (ISO) EXPOSURE LIMITS (FDA)
EO - 20 mg (first 24 hrs.) EO - 250 PPM
ECH - 12 mg (first 24 hrs.) ECH - 250 PPM
EO - 60 mg (first 30 days) EG - 5000 PPM
ECH - 60 mg (first 30 days)
EO 2.5g (Lifetime)
ECH - 50g (Lifetime)
EO average daily dose (prolonged) 2 mg/day
ECH average daily dose (prolonged) 2 mg/day
EO average daily dose (permanent) 0.1 mg/day
ECH average daily dose (Permanent) 2 mg/day
SAMPLE HANDLING
To insure that samples received by Nelson Laboratory are representative of product please be sure to include complete information on sterilization, aeration and proper handling of device. Samples must be sealed, shipped, and stored frozen when analysis is delayed. Samples MUST be shipped on dry ice. Dry ice should remain in the shipping container and be present when the package is opened in the laboratory. The means of shipping the samples will be noted in the final report.
The EO extraction specifics form is recommended when submitting samples for this study.
Limited use device (<24 hrs) EO & ECH (water extraction), one extraction only ISO 10993-7
Devices may be extracted simulated use (usually 3X the expected exposure) up to 24 hrs. They are extracted either fluid path or by immersion with USP purified water and at either body temperature 35-39° or room temperature 20-25°.
EXPOSURE LIMITS (ISO) EXPOSURE LIMITS (FDA)
EO - 20 mg EO - 250 PPM
ECH - 12 mg ECH - 250 PPM
EG - 5000 PPM
SAMPLE HANDLING
To insure that samples received by Nelson Laboratory are representative of product please be sure to include complete information on sterilization, aeration and proper handling of device. Samples must be sealed, shipped, and stored frozen when analysis is delayed. Samples MUST be shipped on dry ice. Dry ice should remain in the shipping container and be present when the package is opened in the laboratory. The means of shipping the samples will be noted in the final report.
The EO extration specific form is recommended when submitting samples for this study.
