Environmental Engineering Reference
In-Depth Information
quantum.physics.than.Newtonian.physics..As.the.science.emerges,.the.mysteries.of.
nanomaterials.will.become.puzzles.that.will.be.solved..The.scientiic.paradigms.for.
nanotechnology.may.take.much.longer.to.decipher.because.conventional.scientiic.
methodologies,.instrumentation,.or.principles.may.not.apply.in.some.of.the.upcom-
ing.studies..Many.fear.that.regulations.put.into.place.to.protect.both.the.workplace.
and.the.environment.will.be.too.little,.too.late.
This.chapter.discusses.one.of.the.mysteries.surrounding.nanotechnology.and.pres-
ents.data.that.scientists.will.ultimately.use.to.solve.the.puzzle..It.faces.the.question:
“If.a.nanomaterial.were.to.be.released.into.the.general.environment,.would.it.pose.a.
signiicant.risk.to.ecological.organisms.such.as.ish.or.wildlife?”
The. answer. begins. with. some. background. information. on. how. toxicologists. assess.
impacts. to. ish. and. wildlife,. referred. to. in. ecological. assessments. as. “ecological.
receptors.”
. undeRlYing PRinCiPles oF eCologiCal
exPosuRe, eFFeCts, and “Risk”
This. section. provides. a. brief. primer. on. ecological. risk. assessment,. to. provide. the.
reader.with.the.context.for.discussing.the.potential.hazards.of.nanomaterials.
8.1.1
t
errestrial
vs
. a
quatiC
e
COsystems
Because. of.obvious.differences. in. habitat,.ecotoxicology.comprises. two.main. cat-
egories. of. environmental. assessment:. (1). terrestrial. and. (2). aquatic.. The. former.
category.addresses.the.impacts.of.chemicals.released.into.the.environment.on.ter-
restrial.species..Examples.include.invertebrates.such.as.earthworms,.bees,.beetles,.
and.grubs;.birds,.including.doves,.quail,.robins,.and.hawks;.reptiles,.such.as.lizards.
and.snakes;.and.mammals,.such.as.shrews,.mice,.foxes,.or.bears..The.latter.category.
includes.aquatic.species,.such.as.phytoplankton.(e.g.,.single.or.multicellular.algae),.
zooplankton. (e.g.,. rotifers,. cladocercans,. paramecia),. benthic. invertebrates. and.
insect.larvae.(e.g.,.maylies,.caddislies,.stonelies).and.ish.(e.g.,.embryos,.fry,.juve-
niles,.or.adults)..Of.course,.some.animals.—.for.example,.amphibians.such.as.frogs,.
toads,.and.salamanders.—.may.spend.portions.of.their.life.cycle.in.both.the.aquatic.
and.terrestrial.environment..Organisms.in.a.third.category,.semiaquatic.receptors,.
strongly. depend. on. waterbodies. for. food. or. sustenance.. These. semiaquatic. recep-
tors.include.ish-eating.birds.(e.g.,.kingisher,.heron,.osprey,.and.eagle).or.mammals.
whose.habitat.is.primarily.aquatic.(e.g.,.beaver,.muskrat,.and.otter).
With.the.possible.exception.of.some.deserts,.these.different.types.of.habitat.are.
not.mutually.exclusive..The.forces.of.the.water.cycle.will.strongly.affect.both.the.fate.
and.the.transport.of.contaminants.within.a.terrestrial.ecosystem..In.addition,.animal.
activity.can.affect.markedly.the.landscape.of.a.terrestrial.ecosystem..The.leg-trap-
ping.of.beavers,.for.example,.was.once.an.accepted.method.in.the.United.States.to.
obtain.their.thick.pelts..Many.states,.however,.now.view.these.traps.as.inhumane.and.
have.banned.their.use..Consequently,.their.populations.are.back.on.the.rise.and,.as.a.
