| With the rapid development of coastal nuclear power in the past 20 years,the coastal ecological environment is facing an increased risk of radioactive pollution,while being affected by the Chernobyl nuclear power plant accident and the Fukushima nuclear power plant accident,the international community is increasingly concerned about the possible biological effects of nuclear radiation on non-human species in the large ecosystem of our earth,and the biological effects of ionizing radiation on marine non-human species are also one of the hotspots studied by domestic and foreign scholars.Studies have shown that a certain dose of ionizing radiation may have an impact on the growth,development,reproduction and heredity of organisms.Compared with the research carried out abroad,China started relatively late in the research on the radiation effects of aquatic organisms,especially marine life,and the basic data of biological species for reference is insufficient,thus further studies on the assessment of the radiation risks to marine ecosystems caused by nuclear radiation are impossible.In this research,the radiation biological effects of sciaenid fishes,the major marine economic fish inhabited around a nuclear power plant in eastern Fujian were studied.The sensitive indicators of gamma-ray radiation damage and the radioactivity level in organisms in the environment of the major economic fish-Pseudosciaena crocea and Nibea albiflora,were observed by indoor simulation and field investigation,the radiation damage of juvenile Pseudosciaena crocea in mortality,feeding rate,antioxidant capacity,digestion and other aspects,as well as the radioactivity level of different tissues and organs of adult Nibea albiflora were obtained.This research is expected to shed light on the future research on the marine fish radiation damage and the development of environment radioactivity safety assessment in the coastal waters surrounding the nuclear power and provide ideas for the research on the effects of ionizing radiation on Marine non-human species in China.The results include:1.60Co gamma-ray external irradiation with different doses(0,4,8,10,32 Gy)was employed in this research for investigating the ionizing radiation damage on the juvenile Pseudosciaena crocea.The results showed that different doses of ?-ray irradiation exposed to the juvenile P.seudo.sciaena crocea:(1)It had no significant effect on body weight,body length and organ index of juvenile Pseudosciaena crocea.(2)Mortality increased with the increase of dose;(3)The ingestion rate decreased with the increase of dose;(4)The stimulation or inhibition performance of antioxidant capacity for the liver and digestive capacity for the gut was present to be significantly different.Among which the significant promotion effect was present in the early stage of the low dose group after irradiation,which showed that the activity of Superoxide Dism utase(SOD),Total antioxidant capacity(T-AOC),amylase,Trypsin and glutathione(GSH)except Maleic Dialdehyde(MDA)increased,but tended to be normal with the increase of time;The high dose irradiation group was inhibited during the culture after irradiation,and the corresponding physiological and biochemical indexes of the internal organs decreased and caused irreversible damage to the juvenile fish.2.The radioactivity levels of artificial and natural radionuclides in different tissues and organs were compared and analyzed by collecting adult Nibea albiflora in the aquaculture base around the nuclear power plant in eastern Fujian.The results showed that:(1)The concentration ability of four tissues and organs(muscle,bone,viscera,gills)of Nibea albijlora was obviously different for different radionuclides.In terms of artificial radionuclides,values of 137Cs contents in muscle,visceral,bone and gill was present to decrease progressively;values of 90Sr contents in muscle,visceral,bone,gill was present to decrease progressively.In terms of natural radionuclides,values of 40K contents in muscle,visceral,gill,bone was present to decrease progressively;values of 23~Th contents in muscle,bone,visceral,gill was present to decrease progressively;values of 210Po contents in visceral,gill,bone,muscle was present to decrease progressively;the concentration regularity of 226Ra was not obvious,but the maxmum accumulation was in fishbone;(4)Since the generally high contribution rate of 210Po in the radiation dose of organisms,the Nibea albiflora collected on site and 8 other organisms include Boleophthalmus pectinirostris,Harpadon nehereus,ostrea gigas tnunb,barnacle,Sinonovacula constricta,Scapharca subcrenata,Charybdis japonica,Oratosquilla oratoria,among which the 210Po specif1c activity were compared and analyzed,the results showed that in biological species,the average specific activity of 210Po from high to low was shellfish>Crustacean>Fish,and the 210Po specific activity of Nibea albiflora muscle was 3.48 Bq·Kg-1(fresh),which is lower than the national limit concentration of 210Po(15 Bq·kg-1)in seafood;(3)Based on the national stand "Specification for assessments of intakes and internal doses of radionuclides",estimated annual effective dose of coastal residents caused by Nibea albiflora muscle intake of radionuclides is about 76.63 Sv·a-1,which was far lower than the annual limit of radionuclides intake given in the national limit of China;(4)The total annual intake of 210Po caused by the intake of the above single seafood is lower than the annual intake national limit of 200Po(2200 Bq·a-1).Firstly,based on the research method of of biology and toxicology,this paper researches the physiological response of Pseudosciaena crocea ionizing radiation damage in the sciaenid fishes of marine economic species in China,which can supplement the study of the biological effects of marine economic fish in China;Secondly,based on the research method of bioconcentration of nuclides,the radionuclide concentration of different tissues and organs of Nibea albiflora,the marine economic sciaenid fishes inhabited around a nuclear power plant in eastern Fujian were studied in this paper.And the specific activity of 210Po in 9 of the main seafood in the same sea area is evaluated,which can provide the basic data and scientific reference for the food safety. |
PDF Full Text Request