TiO2 and ZnO nanoparticles negatively affect wheat growth and soil enzyme activities in agricultural soil.

The properties of nanoparticles and their increased use have raised concerns about their possible harmful effects within the environment. Most studies on their effects have been in aqueous systems. Here we investigated the effect of TiO(2) and ZnO nanoparticles on wheat growth and soil enzyme activities under field conditions. Both of the nanoparticles reduced the biomass of wheat. The TiO(2) nanoparticles were retained in the soil for long periods and primarily adhered to cell walls of wheat. The ZnO nanoparticles dissolved in the soil, thereby enhancing the uptake of toxic Zn by wheat. The nanoparticles also induced significant changes in soil enzyme activities, which are bioindicators of soil quality and health. Soil protease, catalase, and peroxidase activities were inhibited in the presence of the nanoparticles; urease activity was unaffected. The nanoparticles themselves or their dissolved ions were clearly toxic for the soil ecosystem.

[1]  Mark R Wiesner,et al.  Comparison of the abilities of ambient and manufactured nanoparticles to induce cellular toxicity according to an oxidative stress paradigm. , 2006, Nano letters.

[2]  J. Néve,et al.  Trace element status (Se, Cu, Zn) in healthy portuguese subjects of Lisbon population , 2004, Biological Trace Element Research.

[3]  H. Karlsson,et al.  Size-dependent toxicity of metal oxide particles--a comparison between nano- and micrometer size. , 2009, Toxicology letters.

[4]  Baoshan Xing,et al.  Root uptake and phytotoxicity of ZnO nanoparticles. , 2008, Environmental science & technology.

[5]  Stefan Vogt,et al.  Uptake and distribution of ultrasmall anatase TiO2 Alizarin red S nanoconjugates in Arabidopsis thaliana. , 2010, Nano letters.

[6]  B. Nowack,et al.  Occurrence, behavior and effects of nanoparticles in the environment. , 2007, Environmental pollution.

[7]  F. Eivazi,et al.  Factors affecting glucosidase and galactosidase activities in soils , 1990 .

[8]  Qian Hu,et al.  Uptake, translocation, and transmission of carbon nanomaterials in rice plants. , 2009, Small.

[9]  J. Munch,et al.  Lysimeter Experiments to Investigate the Fate of Chemicals in Soils – Comparison of Five Different Lysimeter Systems , 2008 .

[10]  Chao Liu,et al.  Influences of Nano-TiO2 on the chloroplast aging of spinach under light , 2005, Biological Trace Element Research.

[11]  Yunqing Kang,et al.  Toxicological effect of ZnO nanoparticles based on bacteria. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[12]  Pedro J J Alvarez,et al.  Comparative eco-toxicity of nanoscale TiO2, SiO2, and ZnO water suspensions. , 2006, Water research.

[13]  Yan Jin,et al.  Uptake, translocation, and accumulation of manufactured iron oxide nanoparticles by pumpkin plants. , 2008, Journal of environmental monitoring : JEM.

[14]  Rıdvan Kızılkaya,et al.  Effects of N-enriched sewage sludge on soil enzyme activities , 2005 .

[15]  Baoshan Xing,et al.  Phytotoxicity of nanoparticles: inhibition of seed germination and root growth. , 2007, Environmental pollution.

[16]  L. Pruzzo,et al.  Soil quality: a new index based on microbiological and biochemical parameters , 2002, Biology and Fertility of Soils.

[17]  P. Burgos,et al.  Soil enzymatic response to addition of heavy metals with organic residues , 2001, Biology and Fertility of Soils.

[18]  P. Burauel,et al.  Formation and long-term fate of non-extractable residues in outdoor lysimeter studies. , 2000, Environmental pollution.

[19]  D. Delmer,et al.  Determination of the Pore Size of Cell Walls of Living Plant Cells , 1979, Science.

[20]  Nick Serpone,et al.  Inorganic and organic UV filters: Their role and efficacy in sunscreens and suncare products , 2007 .

[21]  Jing Luo,et al.  Effects of particle composition and species on toxicity of metallic nanomaterials in aquatic organisms , 2008, Environmental toxicology and chemistry.

[22]  Milton Sommerfeld,et al.  Toxicity assessment of manufactured nanomaterials using the unicellular green alga Chlamydomonas reinhardtii. , 2008, Chemosphere.

[23]  Anne Kahru,et al.  Toxicity of nanosized and bulk ZnO, CuO and TiO2 to bacteria Vibrio fischeri and crustaceans Daphnia magna and Thamnocephalus platyurus. , 2008, Chemosphere.

[24]  Yang Deng,et al.  Interactions between engineered nanoparticles (ENPs) and plants: phytotoxicity, uptake and accumulation. , 2010, The Science of the total environment.

[25]  Ayten Karaca,et al.  Effect of cadmium contamination with sewage sludge and phosphate fertiliser amendments on soil enzyme activities, microbial structure and available cadmium , 2002, Biology and Fertility of Soils.

[26]  E. Kandeler,et al.  Enzyme Activities and Microbiological and Biochemical Processes in Soil , 2002 .

[27]  T. Hernández,et al.  Toxic effect of cadmium and nickel on soil enzymes and the influence of adding sewage sludge , 2003 .

[28]  G. Oberdörster,et al.  Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine Particles , 2005, Environmental health perspectives.

[29]  F. Hong,et al.  Was improvement of spinach growth by nano-TiO2 treatment related to the changes of Rubisco activase? , 2008, BioMetals.

[30]  E. Bååth.  Effects of heavy metals in soil on microbial processes and populations (a review) , 1989 .

[31]  Baoshan Xing,et al.  Toxicity of nanoparticulate and bulk ZnO, Al2O3 and TiO2 to the nematode Caenorhabditis elegans. , 2009, Environmental pollution.

[32]  Rebecca Klaper,et al.  Behavioral and physiological changes in Daphnia magna when exposed to nanoparticle suspensions (titanium dioxide, nano-C60, and C60HxC70Hx). , 2007, Environmental science & technology.

[33]  T. Xia,et al.  Toxic Potential of Materials at the Nanolevel , 2006, Science.

[34]  Wei Zhu,et al.  Investigation on liver function among population in high background of rare earth area in South China , 2005, Biological Trace Element Research.

[35]  Ghislaine Lacroix,et al.  Biodistribution and clearance of instilled carbon nanotubes in rat lung , 2008, Particle and Fibre Toxicology.

[36]  Janeck J Scott-Fordsmand,et al.  Effects of C60 fullerene nanoparticles on soil bacteria and protozoans , 2008, Environmental toxicology and chemistry.

[37]  C. Rondeau-Mouro,et al.  Assessment of cell wall porosity in Arabidopsis thaliana by NMR spectroscopy. , 2008, International journal of biological macromolecules.

[38]  R Cai,et al.  Solar-driven self-cleaning coating for a painted surface , 2006 .

[39]  Franck Chauvat,et al.  Cytotoxicity of CeO2 nanoparticles for Escherichia coli. Physico-chemical insight of the cytotoxicity mechanism. , 2006, Environmental science & technology.

[40]  Wei Jiang,et al.  Bacterial toxicity comparison between nano- and micro-scaled oxide particles. , 2009, Environmental pollution.

[41]  G. E. Gadd,et al.  Comparative toxicity of nanoparticulate ZnO, bulk ZnO, and ZnCl2 to a freshwater microalga (Pseudokirchneriella subcapitata): the importance of particle solubility. , 2007, Environmental science & technology.

[42]  Fan Yang,et al.  The Improvement of Spinach Growth by Nano-anatase TiO2 Treatment Is Related to Nitrogen Photoreduction , 2007, Biological Trace Element Research.

[43]  A. Stork,et al.  A wind tunnel for measuring the gaseous losses of environmental chemicals from the soil/plant system under field-like conditions , 1994, Environmental science and pollution research international.

[44]  Diego Rubiales,et al.  Nanoparticle penetration and transport in living pumpkin plants: in situ subcellular identification , 2009, BMC Plant Biology.

[45]  Nanna B. Hartmann,et al.  Environmental behavior and ecotoxicity of engineered nanoparticles to algae, plants, and fungi , 2008, Ecotoxicology.