Copper levels in buccal cells of vineyard workers engaged in various activities

Copper-based compounds have been used as agricultural fungicides for many years. Their use in Australia is escalating with increase in the scale of planting and associated pest problems. The objective of this study was to identify viticulture activities associated with high exposure to foliage sprays. It would be determined if occupational exposure of vineyard workers to copper-based sprays was associated with raised body copper levels through analysis of saliva and buccal cells.

The activities of six vineyard workers from four vineyards in the Yarra Valley Victoria, Australia, were monitored over a period of 2 years. During this period, workers carried out seasonal activities, including fungicide spraying, canopy management, and tractor operation. Saliva and buccal cells from workers were collected and analysed for copper levels that were then correlated with the different types of vineyard activity.

The buccal cells of vineyard workers exposed to copper through seasonal activities including fungicide spraying, canopy management, and tractor operation contained copper levels of 0.87, 1.24, and 0.95 ng Cu per 10(6) cells, respectively. This was up to 10-fold higher than the copper levels in buccal cells from the control subjects (0.1 ng Cu per 10(6)). Copper levels in buccal cells from workers participating in other viticulture activities such as shoot thinning, bunch counting, and disbudding were not significantly different from those of control subjects. The levels of copper in saliva samples of both workers undertaking any vineyard activity and control subjects were below the level of detection.

Seasonal activities undertaken in vineyards that involved direct contact with copper, in particular canopy management, fungicidal spraying, and tractor operation were associated with high copper levels in buccal cells of workers. This indicates that copper derived from copper-based fungicidal compounds is accumulated within body cells. The lack of detectable copper levels in saliva suggests that the route of transport of copper into buccal cells is not through saliva. The results indicate potential adverse health risks associated with use of copper fungicide. Recommendations are made in relation to the precautions that should be taken in relation to use of copper sprays and to validate buccal cells as an indicator of body copper status.