Abstract for Poster 29

Evaluation of occupational skin exposure to Folpet during pesticide use on grapes

A.M. Milon*, S.M. Mann, D.V. Vernez, P.O.D. Droz
Institute of Occupational Health Sciences, Lausanne, Switzerland

Background

The skin exposure of grape growers during the use of Folpet, a contact fungicide, was assessed in this study. The aims of this study were to (1) identify the determinant steps of the treatment for the occupational skin exposure, (2) evaluate the workers' awareness for the skin route and (3) work out preventive recommendations.

Method

The study was carried out with the collaboration of three different winegrowing sites where four different treatment systems were in use: manual atomizer, tractor, manual gun and atomizer on caterpillar.

Figure 1. Treatment of the grapes

Exposure with each treatment system was investigated using the following assessment techniques:

· Absorbing pads on various body locations to measure the amount of pesticide deposited on clothes or skin surfaces

· Hand washing to measure all the pesticide deposited at the surface of the hands

· Air sampling to measure the pesticide concentration in the breathing zone of the worker

All analysis was performed by gas chromatography.

The skin uptake corresponding to a 8hours work shift comprising 5hours of pesticide use was estimated using a simple permeation model. The model takes into account the physico-chemical properties of Folpet as well as the thickness of the skin. It allowed the assessment of the total intake referred to a single treatment and the relative contribution of skin absorption and inhalation.

Results

Table 1: total absorption, skin absorption vs inhalation

		Skin		Inhalation		Total/treatment
	Treatment	[mg]	%	[mg]	%	[mg]
1	Tractor	4.64	96.5	0.17	3.5	4.81
2	Tractor	4.64	99.1	0.04	0.9	4.68
3	Caterpillar	4.64	99.4	0.03	0.6	4.67
4	Gun	4.64	99.1	0.04	0.9	4.68
5	Manual work	4.64	100.0	Nd*	Nd*	4.64
6	Manual work	4.64	99.1	0.04	0.9	4.68
7	Atomizer	4.64	76.9	1.39	23.1	6.03
8	Atomizer	4.64	73.9	1.64	26.1	6.28

The main findings are:

· 90% of the total intake is due to skin absorption.

· Skin exposure happens during preparation, treatment and cleaning steps.

· Inhalation exposure increases with the use of atomizer.

Solubility and volatility of the chemicals are good predictors of the percutaneous absorption. The solubility increases the diffusion through the skin, whereas the volatility gives indication on stability on skin surface.

Figure 2. Short sleeves, contact with contaminated grape leaves

Skin exposure happens by deposition of aerosol on the skin, contact with a contaminated surface or splashes on the skin during treatment or preparation of the pesticide solution.

The probability of accidental exposure is function of the number of steps necessary during the preparation and treatment. The major cause of skin exposure is the lack of awareness demonstrated by the workers to this route of exposure and the poor prevention practices.

Conclusion

· The skin route can be the major route for occupational exposure to pesticide.

· The efficiency of the chemical absorption through the skin is determined by the concentration of the chemical, the exposed area and the time of exposure.

Occupational skin exposures will remain important for some time because of the lack of understanding amongst occupational health specialists of the associated risks. Research and dissemination of information on skin exposure should significantly reduce diseases from the dermal route of exposure.

Content last modified: 22 May 2005