• Project number: F 2349
• Institution: Federal Institute for Occupational Safety and Health (BAuA) / TNO innovation for life Healthy Living (The Netherlands) / Benaki Phytopathological Institute [BPI] (Greece)
• Status: Completed Project

Description:

Various methods are deployed in workplaces to measure the contamination of the skin with hazardous chemical agents (dermal exposure). Up until now no adequate scientific studies have been carried out that would have allowed the comparability of these procedures to be assessed. Three measurement methods were therefore compared in the course of the SysDEA project.

Interception: This method involves intercepting the chemical agent that is being used in an activity with a layer of fabric or plastic (gloves, patches, coverall) before it comes into contact with the test subject’s skin, which the agent is prevented from reaching. This fabric or plastic is subsequently analysed chemically in order to determine the level of skin exposure.

Wiping or washing: After it has come into contact with the test subject’s skin during the activity, the chemical agent is either wiped off the skin with a moist wipe or washed off with a liquid. The moist wipe or washing solution is subsequently analysed chemically in order to determine the level of skin exposure.

Fluorescence measurement: In a fluorescence measurement, the test subjects are photographed before and after the activity with the chemical agent. When this is done, a special technique is used to visualize where the skin or clothing has been contaminated. A subsequent chemical analysis is not required if this method is applied.

The exposure of various parts of the body was analysed for several activities, including pouring between containers and spraying. The measurements were conducted for each of three test substances: a water-like liquid, a viscous liquid and a dusty powder.

Higher levels were usually detected on the hands by interception with gloves than by the washing method. Measurement using the glove method is therefore to be recommended for a conservative assessment of hand exposure.

When whole-body exposure was determined, interception using patches detected higher levels for almost all activities with liquids than interception using coveralls. How much the levels of exposure measured differ when patches or coveralls are used depends in particular on the pattern of exposure and therefore the nature of the activity. More measurements may be necessary in order to arrive at a reliable result, especially if uneven patterns of exposure occur during an activity.

Since patches only cover small, representative areas of skin, measurements taken with them have to be converted to find an exposure level for the surface of the whole body or a coverall. Depending on how this calculation was carried out, the total exposure levels found differed from those detected with the coverall method. It is consequently necessary to develop a suitable extrapolation procedure.

The results for body exposure proved to be markedly lower with the fluorescence method than with the other methods. In consequence, the fluorescence method appears less well-suited for the determination of exposure. Nevertheless, it may help to identify the pattern of exposure on the body.