Combined Toxicity Of DBDPE And Cd To The Earthworm Eisenia Fetida

Decabromodiphenyl ethane is a new brominated flame retardant developed by Albemarle in the United States in 1990.It has strong stability and low exudation,it is used to produce high-grade materials such as computers,fax machines,copiers,and home appliances.In 2003,Kierkegaard et al first detected DBDPE in some environmental media.After words,DBDPE has been continuously detected in different environmental media such as atmosphere,water,soil and sediment.At present,DBDPE is widely used,the amount of use is also large,and there is an increasing trend.Cadmium is a transitional heavy metal and is listed as the seventh most dangerous substance for human health.Cadmium can accumulate in the bones and kidneys of the human body,leading to tubular damage,renal insufficiency,osteomalacia and osteoporosis and causing cancers such as lung cancer and prostate cancer.Cadmium slao affects the metabolic function,growth and development and physiological functions of plants and animals.In this study,the toxicity effects of DBDPE and its combination with Cd on earthworms?Eisenia fetida?were studied.In this study,we selected 0,2.5,5,10,20 mg/kg DBDPE and 5mg/kg Cd for single and compound tests in soils,and the indexes were sampled at the 7^th,14^th,21^th and 28^th days after staining.The changes of superoxide dismutase?SOD?,catalase?CAT?,peroxidase?POD?and glutathione s-transferases?GST?activity and the content of reactive oxygen species?ROS?,the content of malondialdehyde?MDA?,the degree of DNA damage of earthworms.The main results are as follows:?1?With the time of exposure increases,the SOD,CAT,and POD activity in the earthworm rose,SOD showed a trend of rising first and then falling.With the time of exposure increases,the MDA and ROS contents of each treatment group showed a trend of increasing first and then decreasing compared with the blank group.?2?With the increase of time,SOD,CAT and POD in earthworm showed an activation state,and overall,the activity was higher than that of DBDPE single group;GST activity was always in a suppressed state.The contents of MDA and ROS in each treatment group was significantly higher than that in the blank group,and the contents in combined group was higher than that in the single group of DBDPE.DBDPE and Cd behaved synergistically.?3?In the DBDPE group of 2.5 mg/kg,the OTM value of DNA in the coelomocyte cells of the earthworm increased significantly.With the increase of DBDPE concentrations,the OTM values increased,and the DNA damage degree of earthworm coelomocyte cells increased with time.?4?When DBDPE and Cd were combined,the OTM value of the earthworm coelomocyte cells increased with the increase of DBDPE concentration and exposure time.DBDPE and Cd behave synergistically.