Environmental Behavior And Ecotoxicological Effects Of P-dichlorobenzene

With the extensive application, attention has been paid to relevant human health and ecological risk of organic synthetic materials such as p-dichlorobenzene (P-DCB) in the old industrial base, northeast China in recent years. Thus, contaminative behavior of P-DCB atmospheric volatilization from snow, water and soil was examined on the basis of the determination of residual dynamics of P-DCB in snow, water and soil using the gas chromatogram method. The study indicated that the volatilization of P-DCB was very rapid with a high rate and obeyed to the first-rank reactive dynamics equation. Under natural conditions, the half-life of P-DCB in water, snow and soil was 2.32-3.25, 0.76-1.20 and 3.60-5.34 days, respectively. The residual time of P-DCB in soil was longer than that in water and snow. Moreover, volatilization of P-DCB in water, snow and soil became faster with the increase in the initial concentration of P-DCB in water, snow and soil, the half-life of P-DCB through volatilization was also shorter with the increase in the initial concentration of P-DCB in water, snow and soil.Ecotoxicological effects of P-DCB on wheat and cabbage seeds were also invistigated. The results showed that there was significantly linear relationship between the inhibitory rate of wheat and cabbage root elongation and shoot elongation and the concentration of P-DCB in soil. With an increase in the concentration of P-DCB in soil, the inhibitory rate of root and shoot elongation of the two crops was linearly and gradually increased. Toxic inhibitory action of P-DCB on wheat and cabbage seeds was different. The half-effect value (IC50) of wheat and cabbage shoot elongation inhibition by P-DCB was 775mg/kg and 851mg/kg, and the half-effect concentration (IC50) based on the inhibition of wheat and cabbage root elongation was 653 mg/kg and 1.83 × 10~3mg/kg, respectively. In the exposed concentration, toxicity of P-DCB inhibiting wheat and cabbage root and shoot elongation was in sequence wheat > cabbage. The endurance of wheat to P-DCB was lower than that of cabbage to P-DCB.In a word, migration behavior of P-DCB in water, snow and soil environment and its toxicological effects on crops were systematically studied. This work provides a...