Oral: Emerging Nano Materials for Disease Management and Insights from Findings in Nano-based Diagnostics
Trophic transfer of engineered nano materials: Will the food chain be compromised?
R. DE LA TORRE-ROCHE (1), J. White (1) (1) Connecticut Agricultural Experiment Station, U.S.A.
The trophic transfer of engineered nanoparticles from soil through terrestrial food chains was evaluated. Cerium oxide (CeO2) and lanthanum oxide (La2O3) bulk and nanoparticles (NP) were added to soil with zucchini, bean or lettuce plants. Leaves were fed to crickets or beetles, which were then fed to secondary consumers (wolf spiders, mantis, or spined soldier bugs). Results from the CeO2 studies showed that Ce content in zucchini and consumers (crickets and spiders) was significantly greater with the NP exposure than bulk metal. Conversely, Ce and La content in beans and lettuce, respectively, did not differ with particle size. Additionally, Ce transfer to beetles feeding on CeO2 NP exposed bean leaves was dependent on the growth stage of the beetles and feeding duration; and was biomagnified in the spined soldier bugs that fed on beetle larvae. Although La trophically transferred from crickets to predatory mantises, the NP levels were equivalent to the bulk metal. In another study, the aging effects of CuO on producers (lettuce) and consumers (crickets and lizards) were investigated. Copper accumulation in lettuce leaves and consumers showed no significant difference upon CuO exposure (0-400 mg/kg) and aging. Interestingly, expression levels of several target genes involved in Cu transport suggest that the mechanisms involved in CuO NPs accumulation are differentially regulated as compared to ionic Cu.