Multiwalled Carbon Nanotubes and C₆₀ Fullerenes Differentially Impact the Accumulation of Weathered Pesticides in Four Agricultural Plants

Abstract

The effect of multiwalled carbon nanotubes (MWCNT) or C60 fullerenes on the uptake of weathered chlordane or DDx (DDT + metabolites) by Cucurbita pepo (zucchini), Zea mays (corn), Solanum lycopersicum (tomato), and Glycine max (soybean) was investigated. The plants were grown in 50 g of soil with weathered chlordane (2150 ng/g) and DDx (118 ng/g) that was amended with 0, 500, 1000, or 5000 mg/kg MWCNT or C60. After 28 d, the root and shoot content of chlordane components and DDx was determined by GC-MS. Zucchini and tomato growth were unaffected by carbon nanomaterial coexposure, although C60 at 500 mg/kg reduced corn and soybean biomass by 36.5-45.0%. Total chlordane content ranged from 1490 (tomato) to 4780 (zucchini) ng; DDx amounts ranged from 77.8 (corn) to 395 ng (zucchini). MWCNT coexposure decreased chlordane and DDx accumulation 21-80% across all crops, depending on species and nanotube concentration. Conversely, C60 had species- and contaminant-specific effects on pesticide uptake, ranging from complete suppression of DDx uptake (corn/tomato) to 34.9% increases in chlordane accumulation (tomato/soybean). The data show that pesticide accumulation varies greatly with crop species and carbon nanomaterial type/concentration. These findings have implications for food safety and for the use of engineered nanomaterials in agriculture.

Carbon nanomaterials: production, impact on plant development, agricultural and environmental applications

“…Uptake of fullerene 14 C60 was also reported for radish (Raphanus sativus), grown for 2 weeks in a sand substrate and hydroponic culture, while a rock wool substrate limited the availability of C60 for plant uptake [146]. Although the principal capacity of plant roots to take up fullerenes has been repeatedly demonstrated, unfortunately more detailed studies on plant availability and root uptake under real soil conditions are still lacking [138,139].…”

“…Analyses of plant tissues revealed no membrane disruptions, suggesting that the contaminants did not enter the plant simply via damaged tissues. Genotypic differences in the uptake rates of DTT metabolites in the presence of fullerene C60 have been reported in plants grown on a vermiculite-soil mixture [138] with inhibitory effects recorded for maize (Z. mays) and tomato (S. lycopersicum) but stimulation in soybean (G. max) and zucchini (C. pepo). Interestingly, in a study conducted on a loamy field soil, containing naturally aged DDE residues, no impact of fullerene C60 amendments on contaminant uptake by pumpkin (C. pepo) was detectable [139].…”

“…In a study of terrestrial plants with fullerene soil amendments used for immobilization of pesticide residues, reduced biomass accumulation was reported at higher fullerene concentrations (500-5000 mg kg −1 soil): up to 40 % reduction for soybean (Glycine max), 44 % for maize (Zea mays) and 10 % for tomato (Solanum lycopersicum) [138], while inhibition of root growth was detected in pumpkin (Cucurbita pepo) [139].…”

Carbon nanotubes: Impacts and behaviour in the terrestrial ecosystem - A review

“…MWCNTs generally minimized toxicity of highly bioavailable PAHs on microbial community. De la TorreRoche et al [70] studied the impacts of MWCNTs and C 60 fullerenes on pesticide accumulation in agricultural plants. MWCNTs decreased chlordane and DDx (DDT þ metabolites) accumulation across the 4 studied plants while C 60 fullerenes completely suppressed DDx uptake but increased chlordane accumulation.…”

“…3) [85,93,94]. Lin et al [93] studied the intergenerational transfer of carbon nanomaterials (carbon nanoparticles C 70 and MWCNTs 40e70 nm diameter) in rice (Oryza sativa L. ssp. japonica, cv Taipei 309).…”