Copper uses in organic production are safe to the nervous system of Caenorhabditis elegans?

Abstract

AbstractThe Bordeaux mixture, fungicides composed of copper sulfate, is commonly used in organic production. This use has been questioned owing to the impact of copper accumulation in the environment, which can affect living organisms negatively. Here, was analyzed the presence of copper levels in soils and in orange and grape juices that received Bordeaux mixture fungicide treatments. Furthermore, we evaluated copper toxicity in Caenorhabditis elegans nematodes by assessing some of their biochemical and behavioral parameters after acute and chronic copper exposure. The metal exposure in vivo was performed at concentrations of 0.05, 0.1, 0.3, and 0.7 mg/L, compared with a control group that received ultrapure water. The results showed that copper was present in the sampled soils at higher levels than in the control area soil. Copper was detected in an average value of 0.25 mg/L in orange juice and 0.69 mg/L in grape juice. The acute and chronic exposure conditions showed behavioral changes and an activation of the acetylcholinesterase enzyme. However, chronic exposure to low copper concentrations led to inhibition of this enzyme. Thus, the copper concentrations detected in the fruit juices acted as modulators of the cholinergic system and modified the behavioral parameters in C. elegans.