Evaluation of single and joint toxic effects of diuron and its main metabolites on natural phototrophic biofilms using a pollution-induced community tolerance (PICT) approach.

This study assessed the single and joint acute toxicity of diuron and two of its metabolites (DCPMU and 3,4-DCA) on natural phototrophic biofilms using a PICT approach with photosynthesis bioassays. River biofilm communities were collected at three sampling stations exhibiting increasing concentrations of diuron, DCPMU and 3,4-DCA from upstream to downstream. Applied individually, the parent compound was more toxic than its metabolites, with DCPMU being more toxic than 3,4-DCA which only inhibited photosynthesis at very high concentrations (EC25 at about 5 mg/l).

Effect of a spreading adjuvant on mesotrione photolysis on wax films.

There is little information about pesticide photostability on plants, especially when considering the effects of the formulation. We evaluated the photostability of a herbicide, mesotrione, on wax films. These surfaces are good systems to mimic the outer layer of the leaf.

The effect of mixing two herbicides mesotrione and nicosulfuron on their photochemical reactivity on cuticular wax film.

There are growing concerns about the environmental impacts of pesticides with a consequent increasing demand for meaningful and accurate information on their consumption and use pattern. Pesticides reactivity towards light is rarely considered at the leaf surface after crop treatment although it is directly impacting the pesticide efficiency. We have established a test on thin wax films which mimic well the leaf surface.