The Distribution Of Dechlorane Plus In Plant Tissues

Dechlorane plus(DP)is a kind of flame retardant,which is widely added in a variety of products.DP has persistence,bioaccumulation and migration.These features make DP widely exists in various environmental media.As plant growth environment,soil is one of the main medium of DP enrichment,but studies about distribution of DP in plant are infrequent at present.Studies have shown that organic pollutants have different environmental behaviors inside and outside greenhouse.According to analyse the distribution of DP in tomato and cucumber tissues under different soil,this study concluded the distribution of DP in different environmental conditions,and forecasted concentration of DP in plant tissues by using partition-limited model.The DP mean percentages of tomato root,stem,leaf and fruit were 13±1.2%,18±3.9%,25±6.7% and 42±4.9% in aged DP soil inside greenhouse,respectively,BCFs ranged from 0.18 to 0.32.The DP mean percentages of cucumber root,stem,leaf and fruit were 18±5.9%,26±10%,14±6.7% and 41±11%,respectively,BCFs ranged from 0.15 to 0.61.The DP mean percentages of tomato root,stem,leaf and fruit were 20±13%,27±6%,18±6.0% and 35±13% in aged soil outside greenhouse,respectively,BCFs ranged from 0.17 to 0.41.The DP mean percentages of cucumber root,stem,leaf and fruit were 24±3.7%,35±9.5%,20±15% and 22±7.0%,respectively,BCFs ranged from 0.17 to 0.27.Because effect of rain and other weather in greenhouse is small,and the amount of particulate matter in the plant surface deposition time more,DP more allocate to the stem,leaf and fruit inside greenhouse.The DP mean percentages of tomato root,stem,leaf and fruit were 74±5.0%,10±5.9%,5.7±1.8% and 11±5.1% in fresh DP soil inside greenhouse,respectively,BCFs ranged from 0.37 to 0.60.The DP mean percentages of cucumber root,stem,leaf and fruit were 51±13%,11±5.4%,16±3.0% and 22±6.0%,respectively,BCFs ranged from 0.26 to 0.59.The DP mean percentages of tomato root,stem,leaf and fruit were 75±9.7%,8.2±1.9%,8.6±6.0% and 7.8±2.6% in aged soil outside greenhouse,respectively,BCFs ranged from 0.17 to 0.81.The DP mean percentages of cucumber root,stem,leaf and fruit were 73±8.6%,7.8±2.9%,11±7.1% and 8.0±2.0%,respectively,BCFs ranged from 0.13 to 0.70.The concentrations of DP in plant root and soil had significant correlation,but the concentrations of DP in stem and leaves had no significant correlation with the concentrations of DP in soil.It may be caused by the weak transmission capacity of DP in plant.The mean BCFs values of fresh DP tomatoes and cucumbers were higher than aged DP's,it may be due to the better biological availability of fresh DP.There was a high estimated accuracy by using partition-limited model to estimate DP concentraions of tomato and cucumber roots,the mean variation were 12% and 19%.To estimate the concentration of stems and leaves,the results were inaccurate,the mean variation were 42% and 47%.Through amending the effect of leaves absorption,the accuracy was improved.