Environmental Engineering Reference
In-Depth Information
(Call.et.al..2001a,b)..As.an.example,.the.LC
50
.values.of.DMP,.DEP,.DBP,.and.
butylbenzyl.phthalate.(BBP).were.28.1,.4.21,.0.63,.and.0.46.mg/L,.respectively,.
for.the.amphipod.
Hyalella azteca
.
IndustrialApplication
PAEs.are.used.as.plasticizers.in.the.plastic.industries..Speciically,.they.are.
incorporated.in.the.polyvinyl.chloride.(PVC),.which.has.been.used.for.over.
half.a.century..PAEs.play.an.important.role.in.increasing.lexibility.and.soft-
ness.to.the.products.such.as.home.furnishings,.daily.used.containers,.food.
packaging,. medical. devices,. and. children's. toys. (Staples. et. al.. 1997).. The.
most.popular.PAE,.DEHP,.has.been.widely.used.as.the.plasticizer.in.chil-
dren's.toys,.toothbrushes,.and.clothing.(National.Toxicology.Program.1995)..
In. Germany,. between. 1994. and. 1995,. DEHP. was. consumed. by. more. than.
250,000.ton,. and. the. consumption. of. total. phthalates. reached. 400,000.ton.
(Fromme.et.al..2002)..DBP.is.used.in.the.manufacturing.of.epoxy.resins.and.
cellulose.esters..DMP,.the.simplest.structure.among.the.phthalate.diesters,.
is.utilized.as.plasticizer.in.cellulose.ester-based.plastics..These.plasticizers,.
due. to. their. benzene. and. alkyl. chain. structure,. combine. with. the. plastic.
molecules. to. form. the. noncovalent. bond. structure.. The. long. alkyl. chain.
structure. helps. reduce. the. rigidity. of. the. polymers. and. increase. the. lex-
ibility.of.their.products.
Not. only. do. PAEs. soften. the. long-chain. molecules. but. can. also. be. used.
as. the. monomer. in. the. polyester. synthesis.. For. example,. both. dimethyl.
isophthalate. (DMI). and. dimethyl. terephthalate. (DMTP). are. used. in. poly-
mer. manufacturing,. for. their. ability. to. react. with. other. esters. in. order. to.
produce.polyesters..They.are.mainly.used.in.the.manufacture.of.electric.and.
electronic. products,. including. video,. ilm,. electrical. capacitors,. and. ibers.
(like. polyethylene. isophthalate-co-terephthalate). (Monarca. et. al.. 1991,. Lee.
et.al..1999)..New.applications.have.also.been.found.recently..Ukielski.(2000).
has. used. these. monomers. to. synthesize. multiblock. terpolymers. as. well..
However,.because.of.their.potential.carcinogenicity,.their.application.is.more.
restricted.by.regulations.from.the.1980s.in.many.countries.(Wilkinson.and.
Lamb.IV.1999).
Occurrence and Fate in the Environment
When.PAEs.are.largely.produced.and.heavily.used.in.industrial.processes,.
their.fate.in.the.environment.has.been.regarded.as.a.problem.(Bauer.et.al..
1998)..Intensive.production.inevitably.increases.the.occurrence.rate.of.this.
group.of.chemicals.in.the.ambient.environment..For.the.purpose.of.moni-
toring. the. behavior. of. PAEs. and. evaluating. their. risks. to. human. health,.
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