Pearl River Delta, A Number Of Organic Pollutants Analysis And Distribution Of Poison In The Sediment Characteristics

Kang Yuebui (Environmental Organic Geochemistry)Directed by: Prof. Sbeng Guoying, Fu JiamoOrganic compounds as PCBs, PAHs, organochlorine pesticides in sediments in pearlhiver Delta have been contminated the water. The purpose of this work was toobtain the data of distribution pattern and vertical variation of priority pollutants inthese areas. The pollution history was reconstructed by analysis the concentrations oftoxic contaminans in core sediments. The core was dated by210Pb method. Organicpollutans were extrated from sediments using Soxhelt procedure withdichloromethene and actone.The analysis method for Polychorobiphenyls(PCBs) in sediment samples werestudied. Quality assurance/quality control (QA/QC) study is also discussed in details.The results reveal that "multi-layer silica gel column" can clean up well the maininterference oforganochlorine pesticides. A standard material (PCB25) ---that is 25kinds of PCB congeners is employed to carry out QA/QC. The recoveries of PCBs asPCB25 range from 97% to ll8%. The detection limit are in the range of 0.5～l.4ng/g.The concendions of PCBs in surface sediments collected from main River in PearlRiver Delta wer quantified by GC/ECD. The order of PCBs concentration in thesediment sample as: GUangthou >Macao>>Shiziyang～West river～Lingdingyang.Each concentration is: Guangzhou 485.45 ng/g, Macao 338.53 ng/g, Shiziyang 25.4ng/g, West river l3. l3 ngig and Lingdingyang 11.46ng/g dry weigh. The distributionpattern of PCB congeners in samples from GuangZhu and Macao indicated that thePCBs of Guanghou came from industry mixtures of Aroclor l260, but that ofMacao from Aredor 1254 and Asoclor l260. The PCBs concentration in samplescollected from Pearl River suggested that the concentration decreased from the upperto lower reaches of the Pearl River with increasing distances from ihdustry area.Samples from Guangzhou Channel and Macao Harbor have been heavilycontaminated by organic compounds. A comparision of the concentration values withLong's guideline vaiues of marine and Estuarine sediment for causing adversebiological effects showed tha PCBs and DDTs were higher than the values ofEffects-Range Median(ERM).The organic contamination history was reconstrUct6d by analysis the concentration ofn- al kane, PAHs, organochlOrine Pestici des in thre e sed imentary core s located inMacao EstUarine, Shenwan in West hiver, Qi'ao in Lingdingyang.Concentfations and different distribUtion patterns of n-alkanes in thesse sedimentcores were reprenseted. FactOr anaiysis was used fOr disceming the contaminatedsoureces of alkanes in sedimenop core of Macao Estuarine. For sediment core ofMacao,the result of the study showed: the sedimenny core rePresented about 40years of dePositional times; The concentration for the total n-alkanes range from0.47-27.5mg/kg (dry wight). Two sarnples represented sedimentary time of l988-l990 which have very high concentration values were contamin8ted by oil. FactOranaIysis reveals may be 4 tyPes conboinated sources, among that the contribution ofland-nmoff is the largest one. The four types contamiIl8ni sources corresponded with4 different composition characteristics of n-alkanes in sedimenfory cores.Concentraton of n-alkan for sedimeniary core in WeSt hiver and Lindingyang werel .3-2.7mg/kg, 0.84-3.lmglkg respectively All three core smpples showed a rise inconcentraion of n-aikane after l989. These implied that the .oil contamination havebeen become seVerelyThe venica1 distribution p8hem of Pesticides concentration with the depthes in threecore sedimentS were discussed. The result shows the concentration of BHCs andDDTs in Macao sedimentary core ranged frOm 0.48-26.28nglg. l .92-39. l3ng/grespectively The distributng charWristics Qf orghanochlorinated pesticides in thecore varied with the water fluxes of Pearl River. They may came from the residue ofagricultural soils. Concentration of DDTs was above the ERL (E...