| Three heavy metals and seven organic compounds of environmental estrogens were chosen as our study subject in this dissertation. After the successful development of simultaneous determination methodology of seven environmental estrogens, the migration behavior of three heavy metals and seven organic compounds was thoroughly studied together with the occurrence of the organic estrogens in twenty-three plastic toys.Firstly, the migration behavior of lead, cadmium and mercury from toys to hand was investigated. Such parameters as toy type, coating area and playing time were examined. The results confirmed the migration of Pb, Cd and Hg from toys coating through hand dust. When playing toys for 2 hours, the migration amount of Pb, Cd and Hg were 0.45-13.50, 0.02-0.26 and 2.198~4.7313μg per hand and the migration rate were 14.38%~77.01%, 0.01%~57.89% and 23.32%-73.23%, respectively. It was also found that washing hands with tap water after playing toys was an effective prevention for cadmium and mercury but not for lead.Secondly, an RP-HPLC was developed to determine five kinds of phthalates and two kinds of phenols within 16min simultaneously and successfully. The relationship coefficients of the calibration curve were >0.998. The detect limit was 0.343ng for dimethyl phthalate, 0.405ng for diethyl phthalate, 0.516ng for di-n-bjtyl phthalate, 0.385ng for di(2-ethylhexyl) phthalate, 0.443ng for di-n-octyl phthalate, 0.227ng for bisphenol A and 0.804ng for 4-nonylphenol.Thirdly, the migration of target compounds was studied in a simulation experiment.Plastic toys were cut into pieces and soaked in a simulating sweat solution or saliva solution. Some parameters, such as the amount of sample, the volume of soaking solution, soaking time and the concentration of salt and surfactants were tested. Experimental results showed that all target compounds were leaked out and some even up to several tens micrograms level. In tested samples the BPA, DBP and DEHP were frequently detected. In tested simulating sweat solution and saliva solution, the occurrence percentage of BPA, DBP and DEHP were 53.3, 56.8 and 86.7 and 78.4,55.6 and 59.5, respectively.Fourthly, evaporation behavior of target compounds was tested with a nitrogen gas flow. Tested samples were cut into pieces and placed in a glass tube. A nitrogen gas flow was led into the tube at the flow rate of 500ml/min. The target compounds were collected in methanol and determined as described above. Some influencing factors, for example, the amount of sample, nitrogen flow rate and temperature, sweeping time were studied. The results showed that all tested compounds were evaporated into the gas. The evaporation amount was increased with the increasing of sample amount, sweeping time and the nitrogen flow rate and temperature. Some tested compounds could be up to submilligram level when swept with nitrogen for 2 to 3 hours.Finally, organic estrogens in twenty-three plastic toys were determined and at least two tested compounds were found in all of them. Among twelve of tested samples at least one target compound was>1.0%.
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