Resistance of medical gloves to permeation by Carmustine  (2001)

Authors

• Nicole Toyick (Deputy Technical Manager) 
• Pete Phillips (Deputy Director) 
• Bruce Fisher (Quality Manager) 
• Paul Edwards (Technical Officer) 

All employed at SMTL.

Introduction

The SMTL were requested to examine the permeability of medical gloves to the cytotoxic drug Carmustine. This document includes data generated for:

1. Welsh Health Supplies: Test results of the latex examination and surgical gloves currently on the All Wales Contract for 2000-2001.
2. Regional Pharmaceutical Committee: Test results of the nitrile examination glove currently on the All Wales Contract for 2000-2001.

Test Method and Definitions

Testing of the gloves was in accordance with BS EN 374 Part 3: 1994, Protective gloves against chemical and micro-organisms; Determination of resistance to permeation by chemicals. The principle of the test is to determine the resistance of a glove material to permeation by a solid or liquid chemical and for the purpose of this report, the alkylating drug Carmustine was utilised at a concentration of 100mg/30ml. With reference to the test results the following definitions apply:

• Permeation: The process by which a chemical moves through a protective glove material on a molecular level. Permeation involves the following:
  1. absorption of molecules of the chemical into the contacted (outside) surface of a material
  2. diffusion of the absorbed molecules in the material
  3. desorption of the molecules from the opposite (inside) surface of the material
• Breakthrough time: The elapsed time between the initial application of a test chemical and the time at which a permeation rate of 1µg/min/cm² is detected
• Permeation rate: The mass of test chemical permeating the glove per unit time per unit area.
• Drug transfer: The quantity of test chemical per unit area of sample which has passed through the sample at the termination of the test.

Test results

Medisavers Bodyguards nitrile powderfree non sterile examination gloves, Medium

Medisavers Bodyguards latex powderfree non sterile examination gloves, Medium

LRC Biogel latex powderfree sterile surgical gloves, 7

Semperit Sempermed Supreme latex powderfree sterile surgical gloves, 7

Notes:

The maximum permeation rate and drug transfer are not specified in the standard. They are included for information only, especially when breakthrough of the drug does not occur.

0.0.0.1 * Where breakthrough did not occur, the duration of the test is reported as required by the standard.

0.0.0.2 NA denotes not applicable

Discussion

As can be seen from the tables above, the nitrile gloves did not show breakthrough (see above for definition) of the carmustine over the test period of 3 hours. The maximum permeation rate during the test was 0.37 µg/min/cm² in one sample, the other two samples showing 0.06 and 0.03 µg/min/cm² respectively.

The latex gloves, in contrast, all broke through well inside the 4 hour test period, with the examination gloves breaking through in around 25 minutes, and the two surgeons gloves at around 45 (Semperit) and 100 (LRC) minutes respectively.

Permeation rates for the latex gloves ranged between 1.1 and 2.15 µg/min/cm².

The total amount of drug transferred (in the column headed `Drug Transfer') should be interpreted carefully, as the test is stopped once breakthrough is detected. This means that the test time for the Bodyguard latex glove was 20-30 minutes, and the total drug transfer of 10-15 µg/cm² took place over this relatively short period, whilst the worst performing Bodyguard Nitrile glove transferred approximately 24µg/cm² over a period of 4 hours.