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Terrestrial Trophic Transfer of Bulk and Nanoparticle La2O3 Does Not Depend on Particle Size
journal contribution
posted on 2015-10-06, 00:00 authored by Roberto De la Torre Roche, Alia Servin, Joseph Hawthorne, Baoshan Xing, Lee A. Newman, Xingmao Ma, Guangcai Chen, Jason C. WhiteThe
bioaccumulation and trophic transfer of bulk and nanoparticle
(NP) La2O3 from soil through a terrestrial food
chain was determined. To investigate the impact of growth conditions,
lettuce (Lactuca sativa) was grown
in 350 or 1200 g of bulk/NP amended soil. Leaf tissues were fed to
crickets (Acheta domesticus) or darkling
beetles (Tenebrionoidea); select crickets
were fed to mantises. In the small pot (350 g), La2O3 exposure reduced plant biomass by 23–30% and La tissue
content did not differ with particle size. In the large pot (1200
g), biomass was unaffected by exposure and La content in the tissues
were significantly greater with bulk particle treatment. Darkling
beetles exposed to bulk and NP La2O3-contaminated
lettuce contained La at 0.18 and 0.08 mg/kg; respectively (significantly
different, P < 0.05). Crickets fed bulk or NP
La2O3-exposed lettuce contained 0.53 and 0.33
mg/kg, respectively (significantly different, P <
0.05) with 48 h of depuration. After 7 d of depuration, La content
did not differ with particle size, indicating that 48 h may be insufficient
to void the digestive system. Mantises that consumed crickets from
bulk and NP-exposed treatments contained La at 0.05–0.060 mg/kg
(statistically equivalent). These results demonstrate that although
La does trophically transfer, biomagnification does not occur and
NP levels are equivalent or less than the bulk metal.