The Potential Ecological Risk Of Neonicotinoids On Apis Mellifera And Its Health Risk To Human

This study selected commonly used neonicotinoids as the research object.According to the assessment method of relative efficiency factor?RPF?,we first investigated the spatial-temporal distribution characteristic of the integration residue of seven neonicotinoids(IMI_RPF)in the crop pollen samples from 12 areas in Zhejiang province for three months in 2016.Based on the preliminary exposure assessment experiment,Zhuji in Shaoxing of Zhejiang province was selected as the field experiment base.We mainly evaluated the effects of different doses and different kinds of neonicotinoids on the mitochondrial copy number of Apis mellifera,and preliminarily revealed the potential ecological risks of neonicotinoids on Apis mellifera.Considering the universality of neonicotinoids exposure in the population,35 young people were selected as subjects of study to determine the correlation between the levels of neonicotinoids residues in the urine of the population and mitochondrial damage in human oral mucosa cells.The main research results are as follows:?1?Different levels of neonicotinoids were detected in 12 stations.The detection frequency of imidacloprid?63.9%?was the highest among the seven neonicotinoids,followed by acetamiprid?58.3%?,clothianidin?36.1%?and dinotefuran?33.3%?.Imidacloprid occupied the biggest proportion in the detected neonicotinoids in Pujiang and Lin'an.Acetamiprid took up the most part in the detected neonicotinoids in Cixi,Wenzhou,Tonglu and Fotang.Dinotefuran was the most widely existed neonicotinoid in Zhuji,Deqing,Yunhe and Taizhou.The contamination pattern of neonicotinoids in the samples was dominated by single contamination pattern.IMI_RPF of seven neonicotinoids were ranged from ND to34.205 ng/g in pollen samples.Wuyi was the most polluted area,and taizhou was the least polluted.The pollution level in April was higher than that in May and June.Results in this section not only showed the residue and spatial-temporal variation of neonicotinoids in crop pollen,but also led us to think about the potential ecological risks of neonicotinoids to bees through this potential exposure pathway.?2?Based on the pollution level of neonicotinoids in crop pollen of 12 stations,we chose zhuji to carry out the field exposure experiment of bees.During the period of exposure,there were some abnormal phenomena in bee colonies,such as abnormal death of queen bee,decreased spawning ability of queen bee,no test flight of new bee,low flying altitude of bees,decline of colony potential,and mite infection,etc.It may be that pesticide exposure causes colony behavior disorders.From the perspective of time-effect relationship,the longer the exposure time of neonicotinoids,the higher the relative copy number of the mitochondrial DNA of bees?RmtDNAcn?.From the dose-effect relationship,compared with other exposure concentrations,the RmtDNAcn reached peak at the 1/2 exposure concentration among four colonies.Changes in the mitochondrial copy number are likely to be an important indicator of mitochondrial damage,and the dose causing the damage may have an effective interval,neither too high nor too low will cause significant changes in the copy number.?3?The detection frequencies of neonicotinoids in urine of young people were ranged from 11.4%to 74.3%,and 2-4 kinds of neonicotinoids were detected in most urine samples.Overall,the detection frequencies of imidacloprid and acetamiprid in urine samples were the highest,and the peak value was 74.3%.The overall detection frequnencies of thiamethoxam and imidaclothiz were the lowest and ranged from11.4%to 34.3%.The overall level of neonicotinoids residues in urine of rural participants were higher than that in the urine of urban participants.Peak residual of neonicotinoids were 4.301?g/L of dinotefuran.According to the correlation of exposure concentration and mtDNAcn,it was found that with the increase of the integrated exposure level of neonicotinoids,the RmtDNAcn in the oral mucosal cells of the population also increased.