Introduction
Gloves are one of the most widely used types of Personal Protective Equipment (PPE). However, their effectiveness in reducing the risk of contamination can be very poor due to inappropriate choice or incorrect use. The mechanisms of skin contamination inside gloves are not well understood, nor are the health consequences of wearing them. Substances can permeate the glove material, but the quoted breakthrough times can be misleading. Permeation could increase with temperature and flexing of the glove during use. Ingress could be around the edges of the gloves, through the seams or through imperfections in the material. Contamination could be transferred from the gloves to the hands through handling. Knowledge of the routes of contamination is required if PPE is to be made more effective and control procedures improved.

Objectives
The main objective of this study is to determine quantitatively the routes and sites of internal contamination of gloves by carrying out a volunteer study.

Methods
The experimental plan comprised three sets of tests carried out in turn on each subject: a) no instruction (medium gloves), b) after instruction (medium gloves), c) after instruction (short gloves). In a), volunteers were asked to wear and remove a pair of medium length gloves and perform a simple task of washing the inside of a fume cupboard. Three repeats were carried out. They were observed to find out where contamination was occurring. Tracer techniques based on non-toxic fluorescent dye and strontium chloride were used to identify and quantify routes of entry. Transepidermal water loss (TEWL) and Corneometry monitored the skin condition of the volunteers before and after the tasks to show the effect on the skin of wearing the gloves. The study was repeated in b) as a second set of trials after showing the volunteers how to remove and use gloves correctly. A third set of trials c) were carried out using short disposable gloves.

Results
The results from the first set of tests (volunteers given no instruction or training) showed high levels of contamination on eight out of ten of the volunteers (equivalent to over 30 microliters of washing solution). The fluorescent dye was mainly on the fingertips that had removed the gloves. After instruction and training on how to use the gloves properly the levels of contamination were considerably reduced to one in ten (up to 3 microliters of solution), and little or no fluorescent dye was found on the volunteers' hands. However, contamination was found on the arms and around the cuff of the gloves of some volunteers even after instruction on how to use gloves. Hand contamination was much greater after using disposable gloves, appearing on three out of ten after training, but this was exacerbated by two faulty glove fingertips that allowed water through.

Discussion
The contamination of the hands can be greatly reduced with proper instruction and training on how to put on and remove gloves. However, even with instruction and training some volunteers still managed to transfer dye onto their arms. The occurrence of two faulty gloves out of thirty pairs is far above what would be expected from Quality Assurance standards.

Further data will be collected on the consequences of these findings by applying the same quantities of contamination to the hands with and without wearing gloves. This time, the contamination will contain n-methyl-pyrrolidone, which quickly penetrates the skin and can be detected by biological monitoring of urine. This experiment will show whether the increased temperature and humidity inside a glove enhances permeation through the skin.