| 1 | Determination of Fe,Ni,Cu,Zn,Cd and Pb in seawater by isotope dilution automatic solid-phase extraction—ICP-MS显示文摘A thorough understanding of the biogeochemical cycling of trace metals in the ocean is crucial because of the important role these elements play in regulating metabolism in marine biotas and thus,the climate.However,a precise and accurate analysis of trace metals in seawater is difficult because they are present at extremely low concentrations in a high salt matrix.In this study,we report an analytical method for the preconcentration and separation of six trace metals,Fe,Ni,Cu,Zn,Cd and Pb,in seawater using a sea FAST automatic solid-phase extraction device,analysis by a triple quadrupole collision/reaction technique with inductively coupled plasma mass spectrometry(ICP-MS),and quantification by the isotope dilution technique.A small volume(10 m L)of seawater sample was mixed with a multi-element isotope spike and subjected to sea FAST procedures.The preconcentrate solution was then analyzed using the optimized collision/reaction cell mode of ICP-MS,with NH_(3)gas for Fe and Cd with a flow rate of 0.22 m L/min and He for Ni,Cu,Zn and Pb with a flow rate of 4.0 m L/min.The procedure blanks were 130 pmol/L,3.0 pmol/L,6.8 pmol/L,37 pmol/L,0.29 pmol/L and 0.42 pmol/L,for Fe,Ni,Cu,Zn,Cd and Pb,respectively.The method was validated using five reference materials(SLRs-6,SLEW-3,CASS-6,NASS-7 and GEOTRACE-GSC),and our results were consistent with the consensus values.The method was further validated by measuring full-water-column seawater samples from the subtropical Northwest Pacific Ocean,and our results demonstrated good oceanic consistency. | Yuncong Ge Ruifeng Zhang Ziyuan Jiang Zhan Shen Maojun Yan | 2022 | Acta Oceanologica Sinica2022，41，8： | 3 |
| 2 | A Large Acute Gastroenteritis Outbreak Associated with Both Campylobacter coli and Human Sapovirus—Beijing Municipality,China,2021显示文摘Summary What is already known about this topic?Campylobacter is a significant foodborne pathogen that leads to global outbreaks of acute gastroenteritis(AGE)usually affecting less than 30 individuals.Human sapovirus(HuSaV)is an enteric virus responsible for sporadic cases and outbreaks of AGE worldwide.In a study conducted in Beijing,HuSaV detection ranked second after norovirus.What is added by this report?We present a discussion of the first large-scale outbreak of AGE caused by both Campylobacter coli(C.coli)and HuSaV.The outbreak involved a total of 996 patients and exhibited two distinct peaks over a period of 17 days.Through case-control studies,we identified exposure to raw water from a secondary water supply system as a significant risk factor.Among 83 patients,49 samples tested positive for C.coli,39 samples tested positive for HuSaV,and 27 samples tested positive for both pathogens using real-time polymerase chain reaction detection.Furthermore,whole-genome sequencing of 17 C.coli isolates obtained from 17 patients revealed that all isolates belonged to a highly clonal strain of C.coli.What are the implications for public health practice?Outbreaks of AGE resulting from multiple pathogen infections warrant increased attention.This report emphasizes the significance of ensuring the safety of drinking water,particularly in secondary supply systems. | Lin Zou Ying Li Guilan Zhou Zhenzhou Huang Changyan Ju Chunyan Zhao Xiang Gao Bojun Zhen Ping Zhang Xiaochen Guo Jing Zhang Yang Zhang Bo Liu Shaolei Zhou Aixia Yan Ying Kang Yanchun Wang Hongmei Ma Xiaohui Li Maojun Zhang | 2023 | China CDC weekly2023，5，52： | 0 |
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