Antimony Pollution In Soil And Water Environment And Its Remediation At E-waste Dismantling Area In Guiyu

In electronic waste?e-waste?dismantling area,the informal e-waste dismantling activity is the main source of metal pollution.Many toxic and harmful metals will remain in e-waste dismantling area,which may disperse from the polluted site to the surrounding water and soil environment,causing further contamination.Therefore,it is necessary to evaluate and remediate the contaminated sites in the e-waste disassembly area.However,most academic research only focused on common metals?such as Cu,Cd,Pb and Zn?in the e-waste dismantling area,but little attention has been paid to some trace metals?e.g.Sb and Sn?,which the actual impact on the environment caused by informal e-waste dismantling activity may be underestimated.Therefore,it is necessary to systematically investigate the migration and transformation rule of metals in the environment nearby the e-waste dismantling area and remediate the heavily polluted metals to protect the environment and human health.In this article,the study area was located in a typical e-waste dismantling area in Guiyu.In the study area,namely burnt site,paddy field and stream were chosen to investigate the contamination distribution and vertical migration of metals.The geo-accumulation index was used to evaluate the metal pollution degree and hazard quotient?HQ?was used to evaluate the human health risk of metals in paddy.Then,Lian River as the study area,the horizontal distribution and pollution source of metal pollutants in the surface sediments were studied.The geo-accumulation index was evaluated metals pollution degree and the potential ecological risk assessment index was evaluated ecological risk.Moreover,the distribution characteristics of metals in water hyacinth were analyzed.Finally,Bidens Pilosa Linn was used to remedy Sb contaminated in the soil through a laboratory test.The main conclusions are as follows:?1?In the horizontal distribution,the concentration of metal in e-waste burnt site soil was significantly higher than that in paddy soil and stream sediment?P<0.05?.The result shows that the surface soil of Ag,Sb,Sn and Zn in e-waste burnt site are extremely severe pollution,and their average values??are 47.9,5003,2527 and 2978 mg·kg^-1,which are484,12202,683 and 82 times to the soil background value,respectively;The surface soil of Cd,Sb,Sn and Zn in paddy field are extremely polluted,and their average values??are3.15,1863,517 and 3126 mg·kg^-1,which are 77,4544,140 and 86 times to the soil background value,respectively;The surface sediment of Sb and Sn in stream are extremely severe pollution,the average values??of which are 294 and 251 mg·kg^-1,respectively,which are 717 and 68 times to the soil background value,respectively.In general,Sb and Sn are the main metal pollutants in the environment of this area.?2?In the vertical distribution,the soil of metals in e-waste burnt site,paddy field and the sediment of metals in stream first increasing then decreasing and tended to be stable,with the increase of the depth.The distribution of metals in paddy is:root>leaf>stem>grain.Among all metals,only BCF of Mo,Cr,Mn,and Ni than 1 indicates that these metals are eapanasddi dlyMy?oias 3bi n2s?oI5pr.na5 bt dehaddeny d sb ipsy3 a 04tp.i.6aa8 l,d?dd2Hi.ys.1Qt,r Tiab hn?uedt?i1ho,.an2z,w a?bhrHiedccQ haq ueus xoe?tt r?io,ee fn mwtte hhl?ieyc Hi hrQ mihs?pik agssc hhtte ooro wfhh suee-atmlwhtaaahnt s rthtieshe kaedlsi t stHhmo;QahT nuhotlefmi naHSgnb Q a h caeotnfai ldvtPi htbS.i,e ns M iinnn Guiyu,which causes the metal pollution in the surface sediments of the tributary of the Lian River is more serious than the mainstream.The geo-accumulation index shows that Ag,Cd,Cu and Sb in the surface sediments of the tributary in Lian River are extremely heavy pollution,Co,Ni,Pb and Sn are severe pollution;Sb in the surface sediments of the main stream in Lian River are severe pollution,Ag,Cd,Cu,Sn and Zn are moderately polluted.The potential ecological risk assessment index indicates that the average value of surface sediment RI in the tributaries of Lian River is 4678.98,which represents a very high ecological risk;the average value of surface sediment RI in the mainstream of Lian River is797.44,which is a high ecological risk.The correlation shows that the contents of Ag,Ni,Cd,Cu,Pb,Sb,Sn and Zn are significantly correlated?p<0.01?,indicating that these metals may ihCnar,v weCa ttuhe,re Mhsayn,am cSei bns,t ohSu fnrr coaen,m d w hZhiignc hih nt om wlaaoitnwelr y i shf yrbaoacsmii nceta-hl lwiysa:srrteoel oadttiissv em lsaytn ethlmiignsh g,alicentaidvviiectsia.et isT.n hgTe t hhceoa tcn otwenanttte enort f hoAyf agm,c ieCnttdah,l has a certain absorption capacity for these metals.?4?Laboratory test shows that the concentration of Sb in the soil for 10,50,and 100mg·kg^-1,Bidens Pilosa Linn has better tolerance to Sb.Moreover,the concentration of Sb in the soil for 250,500,and 1000 mg·kg^-1,Bidens Pilosa Linn has certain tolerance to Sb.At a certain concentration,with the increase of the concentration of Sb in the soil,which can be increased the absorption of Sb by Bidens Pilosa Linn.The bioconcentration factor?BCF?and translocation factor?TF?of Bidens Pilosa Linn are less than 1,but its translocation factor is greater than the bioconcentration factor,indicating that Bidens Pilosa Linn is relatively easy to transfer Sb in the soil to the ground.Bidens Pilosa Linn can be harvested on the plant ground multiple times to achieve the purpose of remediation,which is a potential Sb pollution remediation plant.Moreover,DGT technique is a better method to evaluate the bioavailability of Sb in contaminated soil.