Biomedical Engineering Reference
In-Depth Information
TABLE 10.2 (Continued)
Summary of Ecotoxicity for Metallic Oxide Nanoparticles
Nanomaterial
(Size)
Test Organism
Effect
References
Bacterial
a
100% killing at 20 mg L
-1
[81]
E. coli
LD
50
= 21 mg L
-1
[96]
P. subcapitata
72-h EC
50
~5-10 mg L
-1
[110]
P. subcapitata
72-h EC
50
~0.04 mg L
-1
[92]
50-70 nm
D. magna
48-h LC
50
= 3.2 mg L
-1
[5]
T. platyurus
24-h EC
50
= 0.18 mg L
-1
[5]
C. elegans
24-h LC
50
= 2.3 mg L
-1
[83]
Zebrafish embryo
48-h LC
50
= 1.8 mg L
-1
[84]
20 nm
Plants
r
Root elongation IC
50
< 50 mg L
-1
[70]
ZrO
2
< 100 nm
Microtox
Nontoxic at 100 mg L
-1
[82]
Note:
Hal, adsorbed halides (iodine, bromine, chlorine); MTC, microbial toxic action (50%
effect) [93].
a
Killing efficiency given for three strains:
B. subtilis, E. coli
, and
Pseudomonas fluorescens
[81].
b
Seedlings (corn, cucumber,
Brassica oleracea
, and carrot
Daucus carota
). No effect for bulk alu-
mina. Size for NP aggregates, 200 nm.
c
Activity increase with decrease in nanoparticle diameter,
B. subtilis var. niger
,
S. aureus
[86].
d
Freshwater crustaceans
D. magna
and
Chironomus riparius
.
e
Saccharomyces cerevisiae
. Bulk and nano Zn similar toxicity, Nano-Cu more toxic than bulk.
f
Protozoa
Tetrahymena thermophila
.
g
Use of natural waters containing dissolved organic matter decreased toxicity up to 140-fold
compared with artificial freshwater [111].
h
Marine bacteria
P. phosphoreum
.
i
Bacterial consortium taken from an industrial anaerobic digester, matrix may bind nano-Ag/Cu.
j
Morphological changes in
Hydra attenuata
.
k
MARA = microbial array for risk assessment, growth inhibition of 11 microbial strains.
l
Antimicrobial potency increases from SiO
2
to TiO
2
to ZnO. TiO
2
activity increased by light.
m
Alga
Chroococcus
sp. [98,99] or freshwater alga
Desmodesmus subspicatus
[100].
n
Value for 0.22 μm filtered material [102] Sonicated TiO
2
without effects at 100 mg L
-1
.
o
Chronic (21-day) exposure resulted in severe growth retardation, mortality, and reproductive
defects.
p
Terrestrial isopod
Porcellio scaber
, decrease in antioxidant enzymes GST and catalase.
q
Inhalation study, DNA damage by comet assay, genetic instability as double-strand breaks.
r
For plants such as radish, rape, and ryegrass.
in the absence of sunlight or UV light [58]. Weathering of NM such as quan-
tum dots generally increases the toxicity; however, little is known about the
weathering of most of the NMs [59-61]. Gold NPs are relatively innocuous
in bacterial assays (although gold compounds can retard growth of tubercle
bacillus) [62]; however, a recent study suggests that higher organisms may
respond differently [62]. Gold in colloidal state is not bio-inert as it shows
potent antiarthritic activity in rats, approximately 1000 times more potent
than sodium aurothiomalate, a classic drug used against rheumatoid arthri-
tis and nondisseminated lupus erythematosus [62].
