Environmental Engineering Reference
In-Depth Information
Mice.(C57B1/6)
TiO
2
.
2-5.nm
0.77.or.7.22.mg/m
3
.
(acute.exposure,.4.
hr);.8.8.mg/m
3
.
(subacute.exposure,.4.
hr/day.for.10.days)
Oxidative.stress/
cytotoxicity;.
lung.
histopathology
Acute.exposure:.at.the.high.
concentration,.BAL.luid.
signiicantly.increased;.other.
parameters.did.not.show.
inlammation..Subacute.
exposure:.alveolar.
macrophages.elevated.in.mice.
necropsied.at.weeks.0,.1,.and.
2.post.exposure,.not.elevated.
at.week.3.post.exposure.
Minimal.inlammatory.
response.likely.relects.a.
surface.area.threshold;.
anything.below.this.threshold.
will.cause.little.or.no.
inlammatory.response.
[38]
Mouse.microglia.
cells
Nanosize.TiO
2
.
(Degussa.P25)
826-2368.nm
5-120.ppm.for.6.or.18.
hr
Oxidative.stress
Signiicant.release.of.ROS.
occurred.at.60.min.post.
exposure.at.concentrations.
≥20.ppm;.cell.death.not.
observed.at.all.concentrations
Results.demonstrate.that.TiO
2
.
can.stimulate.microglia.to.
produce.ROS;.however,.
microglia.remained.viable..
Further.study.to.understand.if.
the.ROS.translates.into.neural.
damage.
in situ.
[39]
Human.red.blood.
cells
TiO
2
,.anatase
0.02-0.03.m
5.µg/mL;.incubated.4-
24.hours
Red.blood.cells
TiO
2
.aggregates.with.a.
diameter.≤0.2.µm.were.taken.
up.by.red.blood.cells;.larger.
aggregates.were.stuck.to.
surface.of.cell.membrane.
Results.suggest.that.
nanoparticles.may.penetrate.
red.blood.cells.by.a.
mechanism.other.than.
phagocytosis.and.endocytosis
[40]
Mouse.microglia;.rat.
dopaminergic.
neurons;.and.
embryonic.rat.
striatum
TiO
2
.
Diameter.of.
aggregates:.800.
to.1900.nm.(at.30.
min);.770.nm.(at.
2.hr)
2.5-120.ppm
Neurotoxicity.of.
nerve.cells.
(microglia,.
neuron)
Cytotoxicity.reported.for.
microglia.and.striatum;.TiO
2
.
did.not.cause.toxicity.to.the.
dopaminergic.neurons.
Results.suggest.that.the.
neurotoxicity.of.TiO
2
.is.
mediated.through.microglia-
generated.ROS.
[41]
