Daphnia magna negatively affected by chronic exposure to purified Cry-toxins
2016 (English)In: Food and Chemical Toxicology, ISSN 0278-6915, E-ISSN 1873-6351, Vol. 91, 130-140 p.Article in journal (Refereed) PublishedText
Cry-toxin genes originating from Bacillus thuringiensis are inserted into genetically modified (GM) plants, often called Bt-plants, to provide insect resistance to pests. Significant amounts of Bt-plant residues, and thus Cry-toxins, will be shed to soil and aquatic environments. We exposed Daphnia magna to purified Cry1Ab and Cry2Aa toxins for the full life-span of the animals. We used single toxins in different doses and combinations of toxins and Roundup, another potential stressor on the rise in agricultural ecosystems. Animals exposed to 4.5 mg/L (ppm) of Cry1Ab, Cry2Aa and the combination of both showed markedly higher mortality, smaller body size and very low juvenile production compared to controls. Animals exposed to 0.75 mg/L also showed a tendency towards increased mortality but with increased early fecundity compared to the controls. Roundup stimulated animals to strong early reproductive output at the cost of later rapid mortality. We conclude that i) purified Cry-toxins in high concentrations are toxic to D. magna, indicating alternative modes-of-action for these Cry-toxins; ii) Cry-toxins act in combination, indicating that 'stacked events' may have stronger effects on non-target organisms; iii) further studies need to be done on combinatorial effects of multiple Cry-toxins and herbicides that co-occur in the environment.
Place, publisher, year, edition, pages
2016. Vol. 91, 130-140 p.
Bt-transgenic plants, Cry-toxins, Daphnia magna, Non-target organisms, Roundup, Toxicity
Pharmacology and Toxicology Food Science
IdentifiersURN: urn:nbn:se:umu:diva-121455DOI: 10.1016/j.fct.2016.03.009ISI: 000375629200014PubMedID: 26993955OAI: oai:DiVA.org:umu-121455DiVA: diva2:941160