Data from: Comparing bee species responses to chemical mixtures: common response patterns?

Pollinators in agricultural landscapes can be exposed to mixtures of
pesticides and environmental pollutants. Existing mixture toxicity
modelling approaches, such as the models of concentration addition and
independent action and the mechanistic DEBtox framework have been
previously shown as valuable tools for understanding and ultimately
predicting joint toxicity. Here we apply these mixture models to
investigate the potential to interpret the effects of semi-chronic binary
mixture exposure for three bee species: Apis mellifera, Bombus terrestris
and Osmia bicornis within potentiation and mixture toxicity experiments.
In the potentiation studies, the effect of the insecticide dimethoate with
added propiconazole fungicide and neonicotinoid insecticide clothianidin
with added tau-fluvalinate pyrethroid acaricide showed no difference in
toxicity compared to the single chemical alone. Clothianidin toxicity
showed a small scale, but temporally conserved increase in exposure
conducted in the presence of propiconazole, particularly for B. terrestris
and O. bicornis, the latter showing a near three-fold increase in
clothianidin toxicity in the presence of propiconazole. In the mixture
toxicity studies, the dominant response patterns were of additivity,
however, binary mixtures of clothianidin and dimethoate in A. mellifera,
B. terrestris and male O. bicornis there was evidence of a predominant
antagonistic interaction. Given the ubiquitous nature of exposures to
multiple chemicals, there is an urgent need to consider mixture effects in
pollinator risk assessments. Our analyses suggest that current models,
particularly those that utilise time-series data, such as DEBtox, can be
used to identify additivity as the dominant response pattern and also
those examples of interactions, even when small-scale, that may need to be
taken into account during risk assessment.