Environmental Engineering Reference
In-Depth Information
CurrentContaminationStatusofPBDEs
Environmental Matrices
Air
PBDEs.are.emitted.into.air.and.deposited.into.water.and.soil.during.their.
manufacture. and. usage. in. consumer. products.. When. PBDEs. are. sus-
pended. in. air,. they. may. be. present. with. particles. and. can. deposit. onto.
land.or.water.column.as.the.dust.settles.and.are.eventually.washed.out.by.
snow.and.rainwater..It.is.dificult.to.estimate.how.long.PBDEs.remain.in.
the.air.or.how.far.they.may.travel..PBDEs.do.not.dissolve.easily.in.water;.
therefore,.high.levels.of.PBDEs.are.not.usually.detected.in.the.water.col-
umn.(Liu.et.al..2005a)..When.PBDEs.settle.into.water.columns,.they.tend.
to. stick. to. particles. and. eventually. settle. into. the. sediments. that. act. as.
reservoirs. for. PBDEs,. especially. for. deca-BDE.. Lower. brominated. PBDE.
congeners.such.as.tetra-.and.penta-.BDEs.in.the.water.column.may.enter.
aquatic.organisms.due.to.their.lipophilic.property;.however,.PBDEs.do.not.
enter. groundwater. since. they. tend. to. bind. strongly. to. soil. particles. (Liu.
et.al..2005a).
When.comparing.data.presented.in.Tables.7.1.and.7.2,.PBDEs.in.the.atmo-
sphere. of. coastal. areas. were. relatively. lower. among. industrial. areas. and.
densely. populated. cities;. for. example,. the. average. concentration. of. PBDEs.
in.Hsinchu.County.of.Taiwan.was.48.5.pg/m
3
.(Wang.et.al..2011),.a.rate.simi-
lar. to. Yuen. Long. (urban. site). and. Hok. Tsui. (rural. site). in. Hong. Kong. (69.0.
and.33.8.pg/m
3
.respectively),.whereas.in.Tsuen.Wan.(Hong.Kong),.a.residen-
tial. area. mixed. with. light. industry,. the. concentration. was. 358.pg/m
3
.. The.
concentrations. of. atmospheric. PBDEs. in. Li. Wan. and. Tian. He,. two. inland.
sites.within.Guangzhou.City,.with.heavy.trafic,.reached.204.and.372.pg/m
3
,.
respectively,. which. is. about. 4.5-8. times. higher. than. the. coastal. residen-
tial. areas.. The. atmosphere. over. the. industrial. areas. of. Dongguan. (mainly.
textiles). and. Shenzhen. had. rather. high. concentrations. of. PBDEs,. 204. and.
372.pg/m,.respectively..At.the.e-waste.recycling.site.of.Guiyu,.total.PBDEs.in.
air.reached.21,474.pg/m
3
.(Deng.et.al..2007),.which.was.430.times.higher.than.
that.found.in.the.coastal.areas.(Chen.et.al..2008a).
Among. all. the. PBDE. congeners,. BDE-47,. 99,. and. 209. were. the. main. con-
geners. in. the. air. samples. of. Dali. (e-waste. recycling. areas). and. Dongguan.
(mainly.textiles);.both.are.located.in.Guangdong.Province..The.low.bromi-
nated. congeners. such. as. BDE-28. mainly. exist. in. aerosol.. BDE-209. is. only.
associated.with.particles,.but.penta-,.hexa-,.and.octa-BDEs.exist.in.both.par-
ticles.and.aerosols,.which.was.deduced.from.the.air.samples.collected.from.
the. e-waste. recycling. site. in. Southern. China. (Dali.and. Guiyu).(Chen. et. al..
2008a,b).. The. air. of. industrial. and. urban. areas. of. Guangzhou. City. mainly.
contained.penta-BDE.and.deca-BDE,.relecting.that.the.two.congeners.were.
derived.from.manufacturing.industries.
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