ABSTRACT
Objective To understand the status of new coronavirus contamination in the biosafety laboratory environment, identify key areas prone to contamination, and provide evidence for disinfection of central objects. Methods surfaces of high-frequency contact environment and protective equipment were sampled with moistened sterile cotton swabs after experiment and before disinfection, the results of the one-step real-time reverse transcription polymerase chain reaction (RT-PCR) of open reading frame 1ab and N fragment were used to evaluate the pollution status. Results Environmental surveys found 4 of 217 samples of environmental objects to be positive for new coronavirus RNA, that positive rate was 1.84%. Among them, BSL-3, BSL-2, and BSL-1 were sampled 23, 184, and 10 respectively. The 3 positive samples were from surfaces of nucleic acid extraction room of BSL-2 and from the handles of pass-through box, laboratory door handles and the outer surface of the alcohol watering pot respectively. The 1 positive sample was from the forearm of the protective clothing in BSL-2 laboratory. Conclusion There was a certain degree of virus pollution in key areas of the new coronavirus laboratory. The BSL-2 laboratory has a higher risk of environmental pollution than the BSL-3 and BSL-1 laboratories.
ABSTRACT
Objective To observe the toxicity of fangyouling after one month’s transdermal administration in rabbits and evaluate its security. Methods Forty rabbits were randomly divided into 4 groups including a control group and low,middle and high dose groups of fangyouling. The rabbits in the control group were administered with sunflower oil,and the other rabbits were administrated dermally with fangyouling of 50,300 and 2 000 mg/kg respectively once a day for 4 weeks. The general con?dition,the skin irritation reaction,body weight,food consumption,hematology,blood biochemistry,organ coefficients and his?topathological changes of all the rabbits were observed. Results There was no obvious effect on the general condition in all the rabbits. However,the mild skin irritation was observed in 2 rabbits of the middle dose group and 4 rabbits of the high?dose group. The decreases of body weight and food consumption were noted in the high dose group. No changes were detected of hema?tology,blood biochemistry or viscera pathological at all dose levels. Conclusion The dose of non?toxic response of fangyouling is 50 mg/kg at this study condition.