Third Day Poster Session, 17 June 2010 - NanoTR-VI

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Poster Session, Thursday, June 17
Theme F686 - N1123
The Effects of Two Different Types Silver Nanoparticles on Survival of Sac Fry Rainbow Trout
(Oncorhynchus mykiss)
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USayed Ali JohariUP P* , Mohammad Reza KalbassiP Pand Saba AsghariP
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PPhD Student, Member of Young Researchers Club, Islamic Azad University, Science and Research Branch, Tehran, I. R. Iran
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PDepartment of Fisheries, Marine Science Faculty, Tarbiat Modares University, I. R. Iran
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PMember of Young Researchers Club, Islamic Azad University, Science and Research Branch, Tehran, I. R. Iran
Abstract- We studied responce of sac fry rainbow trout to powder and colloidal silver nanoparticles by calculating Median lethal concentration
(LCR50R) of these two AgNPs forms. 96h LCR50 Rvalues were 0.25 and 36.93 ppm for colloidal and powder AgNPs respectively. Our results
demonstrate that colloidal nanosilver is more toxic to sac fry rainbow trout compare to powdered type.
Manufactured nanomaterials are materials with diameters
ranging from 1 to 100 nanometers (nm), while nanotechnology
is one of the fastest growing sectors of the hi-tech economy
[1]. Although the applications of nanoparticles are increasing
broadly in every field, concerns about their environmental and
health impacts remain unresolved. The use of nanomaterials is
also likely to result in their release into aquatic environments
and may pose risks to aquatic ecosystems [2,3]. The aquatic
ecotoxicology of engineered nanomaterials is a relatively new
and evolving field.
Silver nanoparticles (AgNPs), have been, and continue to be,
recognized world wide as either a cure or as a preventive for
bacterial, fungal, and viral diseases [4]. Few researchers,
however, have investigated the toxicity of silver nanomaterials
in aquatic environments, especially in the case of fishes.
In this study, the lethal effects of two forms of silver
nanoparticles (powdered and colloidal forms) were surveyed
on sac fry rainbow trout. This stage of life cycle of fishes is
ecotoxicologically important because the sac fry are still
receiving nutrition from the yolk and haven’t any alimentary
relation to environment. Therefore results of this stage, will
shown only external impacts of chemicals on fishes.
The colloidal silver nanoparticle, type L (commercial name:
Nanocid, 4000ppm Ag concentration, 10 nm average size) was
supplied from Pars Nano Nasb Co. Ltd, (Tehran, I. R. Iran).
This product registered by United States Patent Application
No: HT20090013825TH [5].
The silver nanoparticle powder (99% pure, 20nm average size)
was purchased from Xuzhou Hongwu Nanometer Material Co.
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Ltd, (Jiangsu China). A Stock solution of 500 mg lP
Pdispersed
AgNPs was prepared after considering the recommendations
of the manufacturer. First 100mg suspending reagent was
added to 1 litter of deionized water, after stirring on magnet
stirrer, 500 mg AgNPs powder was added to this solution and
stirring was continued for 24 hours.
Sac fry rainbow trout (n=480) from same brood of the
holding stock were randomly selected two days after hatching,
and exposed in a 1L cylindrical glass beaker containing the
desired concentration of the test chemical in the statistic
exposure regime. Logarithmic series of nanosilver
concentrations were choice according to OECD guideline for
the testing of chemicals [6]. The selected concentrations were
0.1, 0.32, 1, 3.2, 10, 32, and 100 ppm for each chemical. Each
concentration was tested in triplicate, plus three control groups
for each form of AgNPs. Ten healthy sac fry rainbow trout
were tested in each replicate (30fish/treatment).
Calculated LCR50R values of colloidal nanosilver at 24, 48, 72
and 96 h were 2.75, 0.44, 0.35 and 0.25 ppm, respectively.
About powdered silver nanoparticles, LCR50R values were
calculated to be 186.42, 69.37, 36.93, and 28.25 ppm at 24,
48, 72 and 96 h respectively.
In summary, we think that more investigation about risks
potentials of silver and other nanoparticles should be attended
before they become more and more prevalence in routine
applications by all people in the world. Special attention
should be spending about fishes as some important part of
aquatic environments. More studies should be carrying out
about chronic effects of lowest doses of AgNPs on fishes such
as Rainbow trout. Also other life stages of fishes should be
considered in such nanoecoltoxicological studies.
Table 1. Magnitude of MATC, LOEC, NOEC of colloidal and
powdered silver nanoparticles on sac fry rainbow trout during 96h
Parameter MATC NOEC LOEC
Colloidal AgNPs 0.025 0.01 0.08
Powdered AgNPs 2.825 1 7.10
Figure 1. Agglomerated colloidal (Left) and powdered (Right) silver
nanoparticles in contact with fish mucus. Aggregated nanoparticles
were trap under gill operculum and inside the mouth of fishes
*Corresponding author: HTsajohari@gmail.comT
[1] Y. J. Chae et al., Aquat. Toxicol, 94, 320-327 (2009),
[2] M. N. Moore, Environ. Int. 32, 967–976 (2006),
[3] R. D. Handy et al., Ecotoxicology 17, 396–409 (2008),
[4] A. R. Shahverdi., et al Nanomedicine: Nanotechnology, Biology,
and Medicine 3, 168–171 (2007)
[5] J. Rahman Nia, US Patent application docket 20090013825
(2009)
[6] OECD 215, Fish, Juvenile Growth Test, (2000)
6th Nanoscience and Nanotechnology Conference, zmir, 2010 801