One risk associated with the growing of insect-resistant genetically engineered maize varieties expressing Cry proteins derived from Bacillus thuringiensis (Bt) is their potential to adversely affect non-target organisms. Adults of the common green lacewing, Chrysoperla carnea, are prevalent pollen-consumers in maize that could therefore be exposed to insecticidal proteins expressed in the pollen of these maize varieties.

Yunhe Li, Michael Meissle and Jörg Romeis from Agroscope ART in Zurich, Switzerland, conducted a laboratory experiment to evaluate the impact of pollen from both Cry3Bb1(Event MON 88017) and Cry1Ab (Event Bt176)-expressing transgenic maize varieties on a number of fitness parameters of adult C. carnea. An additional experiment aimed at adding certainty to the hazard assessment included feeding adult C. carnea with an artificial diet containing purified Cry3Bb1 or Cry1Ab toxin at a 10 times higher concentration than in maize pollen. This worst-case experiment intended to prove that the insects are not sensitive to the tested toxins independent from the plant background. In both experiments, no impacts of the two Cry proteins on any of the tested life-table parameters were recorded. The results show that consumption of maize pollen containing those Bt toxins poses a negligible risk to adult C. carnea.

The open access article published in PLoS ONE is available at http://www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0002909.