| In this paper, phytoconcentration and phytodegradation of two types of typical endocrine disrupting chemicals, phthalates compounds (dibutyl phthalate (DBP) and diethylhexyl phthalate (DEHP))and organochlorine pesticides (Hexachlorocycloh- ex-ane (HCHs)and 1,1,1-trichloro-2, 2, bis(P-chloro-phenyl)ethane (DDTs)), in typical submerged plants in bioremediation, Hydrilla verticillata and Potamogeton crispus L. were investigated. Field monitoring of HCHs and DDTs in Potamogeton crispus L. in Haihe was also carried out.Results of field sampling showed that HCHs and DDTs were detected in all of the samples of waters and Potamogeton crispus L. from Haihe River. On March 29, 2008, HCHs concentrations in surface water of Haihe River were in the range of 11.11 14.34 ng/L (mean 13.06 ng/L). DDTs concentrations ranged from 6.88 8.23 ng/L, (mean 7.35 ng/L). Organochlorine pesticides concentrations in the whole Potamogeton crispus L. were in the range of 2.19 27.16 ng/g (mean 10.47 ng/g) for HCHs, 1.41 3.83 ng/g (mean 2.05 ng/g) for DDTs, respectively. Generally, concentration of HCHs in Potamogeton crispus L. was significantly higher than that of DDTs. The enrichment capacity of HCHs by Potamogeton crispus L. leaves was greater than that by stem, while the enrichment capacity of DDTs by stem was greater than that by leaves.The experimental results indicated that the phytodegradation of phthalates compounds and organochlorine pesticides in plant solution fitted well to the first-order kinetic equation. The accumulation and degradation processes of Hydrilla verticillata and Potamogeton crispus L. included three stages, which were surface adsorption, transfer in plants and degradation.Surface adsorption of DBP by Hydrilla verticillata was faster than that of DEHP. By transferring into the plants, concentrations and bioaccumulation factors of DBP and DEHP in Hydrilla verticillata reached the maxima of 15.04 mg/kg and 68.59 mg/kg, respectively. The bioaccumulation factors of DBP and DEHP by Hydrilla verticillata gradually increased during 192 hours, and reached the maxima of 342.18 and 280.18. DBP and DEHP in Hydrilla verticillata was mainly distributed in cell wall. The degradation rates of DBP and DEHP by Hydrilla verticillata were 1.04×10-2 h-1and 0.27×10-2 h-1, respectively.Concentration ofα-HCH,γ-HCH and p,p'-DDT in Hydrilla verticillata first increased then decreased and tended to be stable, reached the maxima of 0.71 mg/kg, 0.66 mg/kg and 4.35 mg/kg at 48 hours.α-HCH,γ-HCH and p,p'-DDT in Hydrilla verticillata was mainly stayed in the leaves. Degradation rates ofα-HCH,γ-HCH and p,p'-DDT by Hydrilla verticillata were 0.41×10-2 h-1, 0.42×10-2 h-1and 0.32×10-2 h-1, respectively.Concentration ofα-HCH andγ-HCH in Potamogeton crispus L. first increased and then decreased, reached the maxima of 0.43 mg/kg and 0.36 mg/kg at 96 hours. The concentration of p,p'-DDT in Potamogeton crispus L. first increased then decreased and went up continually, reached the maxima of 2.28 mg/kg at 24 hours.α-HCH andγ-HCH in Potamogeton crispus L., was mainly concentrated in the leaves and in the cell of the stem. p,p'-DDT was mainly concentrated on the cell wall of the leaves. The degradation rates ofα-HCH,γ-HCH and p,p'-DDT by Potamogeton crispus L. were 0.14×10-2 h-1, 0.20×10-2 h-1and 0.03×10-2 h-1, respectively. The degradation effect ofα-HCH,γ-HCH and p,p'-DDT by Hydrilla verticillata was significantly higher than that by Potamogeton crispus L..
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