Study On DEHP Toxicity Based On DEHP Risk Assessment Safety Dose Design

DEHP belongs to the phthalate esters(PAEs),is one of the most widely used plasticizers in the world.DEHP is easily released from the product to the surrounding environment due to the use of time,and then through the drinking water,feeding and breathing and other ways to enter the organism,and ultimately to the environment And the health of the body causing harm.After the event of Taiwan's plasticizer in 2011,DEHP caused by food safety issues have been widely public attention.2012 China's food safety risk assessment expert committee gives the crowd contact DEHP recommended value,that for 60kg weight,the daily intake of 3.0mg DEHP is safe.Studies suggest that 90%of the body's intake of DEHP is from a diet,and that dietary intake actually refers to the amount of DEHP used in food packaging.Therefore,in the new national standard,which is to be used on October 19,2017 for restrictions on the use of additives in food contact materials and supplies,it is not only stipulated that DEHP should not add more than 5%of the amount of PVC material,and that DEHP-containing materials and articles Can not be used for contact with fatty foods,ethanol content of more than 20%of food and infant food,and the amount of migration should not exceed 1.5mg/kg.Although the national standard from the food contact materials control DEHP migration,but the current study reported in the medical equipment,decoration materials and cosmetics and other materials in the migration can not be underestimated.In recent years,DEHP has been identified as an environmental endocrine disrupter(EEDs),can have a certain impact on the reproductive and reproductive capacity of organisms,DEHP toxicity on the impact of research reports are increasing,people are increasingly concerned about DEHP on the human body Health does not cause an impact on the safety limits.Therefore,the experimental rats were subjected to DEHP 90 days oral toxicity test,the risk assessment committee recommended DEHP safety limit(3.0mg/person/day),that is,the human safety dose should be 0.05mg/kg for The lowest dose,taking into account the uncertainty of the coefficient of 100(10X10),that rats test to 5mg/kg as the lowest dose group,and then 5mg/kg 10,100 and 500 times the establishment of DEHP experimental group dose gradient of 5,50,500,2500mg/kg and the control group and DEHP exposure recovery group,a total of 6 rats,each group of 20 rats,male and female half.The animals in the restorative group were stopped for DEHP for 30 days to observe the reversibility,persistence and delayed effects of DEHP toxicity.During the test period,the general toxicity of the animals was observed at least once a day,and the signs,extent and duration of the poisoning of the rats were recorded.Daily intake of body weight,food intake,calculation of food utilization;blood tests,blood biochemical tests and other conventional indicators,focusing on the detection of neurotoxicity indicators and nerve and reproductive target organ anatomy and pathological examination.To determine the DEHP oral safety,reproductive and neurological and other target organ toxicity indicators DEHP on rats 90 days oral toxicity test,in order to get on the safety limits of DEHP toxicity,lay the foundation for further risk assessment of DEHP.MethodsEffects of sub-chronic exacerbation of DEHP on general indexes of rats Daily observation of the general situation of rats(including general performance,behavior,poisoning and death,etc.);Record a weekly weight and twice the food intake,and calculate the total food utilization;The liver,kidney,spleen,testis,epididymis,the whole brain were dissected and weighed,the ratio of dirty/body was calculated and analyzed statistically.Effects of DEHP exposure on biochemical and hematological parameters in rats The whole blood of rats was taken and the biochemical indexes such as TP,ALB,ALT,AST,ALP,BUN,Cre,GLU,K,Na,Ca,P,TG and CHOL were detected by serum biochemical analyzer.The parameters of WBC,RBC,HGB,HCT,MCV,MCH,MCHC,CMCH,RDW,HDW,PLT,MPV,NEUT,EOS,BASO,MONO,LYM,LUC and their corresponding percentage were measured by automatic blood cell analyzer.SPSS statistical software analysis results.Effects of DEHP exposure on sperm motility and brain lipid peroxidation in rats The effects of DEHP on the sperm motility of rats were studied by using the spermatozoa of rat epididymal sperm.The parameters of the spermatozoa were measured by CASA instrument,including VCL,VSL,VAP,ALH,LIN,STR,BCF And other parameters;DEHP on brain lipid peroxidation:The brain tissue was prepared by ultrasonic homogenate into a brain homogenate.The supernatant was cryopreserved at-20 ? for reactive oxygen species(ROS),lipid oxidation product(MDA)As well as the determination of protein concentration.Effects of sub-chronic hypoxia on histopathology in rats rats were sacrificed and the liver,kidney,adrenal gland,spleen,gastrointestinal tract,testis(ovary),epididymis and whole brain were removed and removed of the tissue immediately placed in the pre-prepared 10%of the formalin fixative fixed.Histopathological paraffin sections were made and histopathological changes were observed.ResultsEffects of sub-chronic exacerbation of DEHP on general indexes of rats There were no significant differences in the control group,5,50 and 500mg/kg groups,while the 2500mg/kg DEHP group showed mental excitement,fluffy,(Including head and neck,limbs and abdomen)and other symptoms of poisoning,the food intake also decreased,the body weight decreased significantly after exposure(P<0.05);There was no significant difference in the overall utilization rate(P>0.05).Compared with the control group,the ratio of liver,kidney and epididymis of the rats was significantly different(P<0.05 or P<0.01).When the dose was increased to 2500mg/kg,the ratio of dirty body in liver,kidney,spleen,brain,testis and epididymis of rats was different from that of control group,and the difference was statistically significant(P<0.05 or P<0.01).Effects of DEHP exposure on biochemical and hematological parameters in rats Blood biochemical indicators:liver and kidney-related biochemical indicators in the DEHP exposure dose of 500mg/kg began to appear abnormal;The biochemical indexes associated with the metabolism of inorganic salts were abnormal when the dose of DEHP was 2500mg/kg.In the biochemical indexes related to lipid metabolism,the CHOL content decreased at 500mg/kg and 2500mg/kg,which was statistically significant compared with the control group(P<0.01).There was no abnormal TG content in the female and male rats.The effect of blood cells on white blood cells:When the dose was 500mg/kg,LYM increased and EOS decreased,and the number of white blood cells decreased at 2500mg/kg.For the red blood cell-related indicators,the dose of 500mg/kg,HGB and MCH indicators decreased,when the dose increased,all the changes in indicators;There was no significant difference in PLT between the DEHP group and the control group(P>0.05).The MPV of the rats was decreased after the recovery period,which was statistically significant(P<0.05 or P<0.01)compared with the control group.Effects of DEHP exposure on sperm motility and brain lipid peroxidation in rats Effects of sperm motility in rats:5mg/kg dose of DEHP can affect sperm motility LIN,DEHP exposure dose of 50mg/kg,the BCF also has an impact,indicating that the sperm activity is also reduced;in 500mg/kg In the dose group,VAP,VSL,VCL,ALH,BCF,LIN,STR and ELON were decreased in the dose group,and all CASA test results in DEHP group and recovery group were all 0.Effects of brain lipid peroxidation:ROS levels increased first and then decreased with the increase of exposure dose,and MDA level increased with the increase of exposure dose.Effects of sub-chronic hypoxia on histopathology in rats DEHP exposure to 5mg/kg,only observed in some rat organs see a small amount of inflammatory response,no pathological lesions;when the dose of 50mg/kg rats liver,kidney,testis,epididymis and ovaries were pathological changes,And with the dose of increased lesions increased;after 30 days after the recovery period,the epididymis no significant recovery.ConclusionThrough the 90-day oral toxicity test of rats,it can be concluded that the reproductive organs of the first male rats are the target organ of DEHP toxicity,especially the detection of the dirty body of the epididymis,the detection of sperm motility and the pathological examination The epididymis was most sensitive to DEHP toxicity,and the dose of 5mg/(kg · d)could have an effect on the motor linearity of the spermatozoa and was the most effective organ,and after 30 days of recovery period,no recovery.The toxicity of DEHP to female and male rats was different.The results showed that the tolerance of DEHP to female rats was stronger than that of male rats,and the delayed effects were obtained.The tolerance to male and female rats was different should also be further long-term experimental observation.Observed test indicators can be DEHP has a significant dose-effect relationship,most of the indicators with the DEHP dose increase significantly increased or decreased.DEHP has an effect on the metabolic process of rats.DEHP in rat brain lipid peroxidation test may be through its oxidative damage to rat brain cells,the brain tissue damage to rats,Of neurotoxicity.