As a most common algal toxin in eutrophic freshwater body, microcystins can be produced by the bloom-forming Cyanophyta microcystis, it has become a potential hazardous substance in aquatic environments for its toxic, distribution and stability. With the increasing recognition of microcystins, China had added microcystin-LR into the related water quality standards. It is very important to detect and control the microcystins in the aquatic environment. This paper systematically introduced the current situation of researches about the determination and pollution control technique of microcystins in drinking water at home and abroad in resent years and then some issues worth of paying more attention to and doing further study in pollution control in future were presented.

Objective To study the effects of overdose fluoride on blood lipid and hemorheology in rabbits and the protective effect of selenium. Methods Twenty male rabbits were divided into 4 groups: normal group,fluorine group(100 mg/L),selenium group(1 mg/L) and selenium (1 mg/L) plus fluorine (100 mg/L) group. After 6 months of treatment,whole blood rheology,blood serum TC,TG,HDL-C,LDL-C,SOD activity,GSH-Px activity,the content of MDA were determined. Results The whole blood rheology of rabbit in fluorine group was abnormal. Compared with the normal group,significant increase of blood serum TC,HDL-C,LDL-C was seen,decrease of SOD activity and GSH-Px activity and increase of the content of MDA in fluorine group was found. The results of selenium plus fluorine group was more close to the normal group compared with fluorine group. Conclusion Fluorosis can induce hemorheology and lipid metabolism disorder and decrease the capacity of antioxidase and moderate selenium intake may have some protective effect.

Objective To investigate whether there was arsenic and selenium pollution besides fluorine pollution in the capsicum and corn roasted by coal-combustion in Zhaotong fluorosis areas were collected,and the cumulation in human hair. Methods In September 2005,the capsicum and corn samples were collected before they were roasted and after roasted by coal-combustion,and the hair samples from people living in Zhaotong fluorosis areas were collected,and the fluorine,arsenic and selenium content in these samples were determined. Results The average arsenic and selenium content in the fresh capsicum not roasted by coal-combustion were 0.034 mg/kg and 0.079 mg/kg respectively. The average arsenic and selenium content in the capsicum roasted by coal-combustion were 0.463 mg/kg and 1.088 mg/kg respectively. The average arsenic and selenium content in the fresh corn were 0.019 mg/kg and 0.051 mg/kg respectively. The average arsenic and selenium content in the corn roasted by coal-combustion were 0.058 mg/kg and 0.085 mg/kg respectively. Except for the average selenium content of the capsicum roasted by coal-combustion,others were all within the limits of arsenic and selenium in foods. Conclusion There is not only fluorine pollution in the capsicum and corn roasted by coal-combustion,but also arsenic and selenium pollution. Furthermore,the selenium pollution level was higher than that of arsenic pollution. The arsenic and selenium pollution level in capsicum was higher than that in the corn. Though this arsenic pollution in the capsicum and corn may be harmful for the people living on these capsicum and corn roasted by coal-combustion to some extent,it was not harmful enough to result in arsenism. Comparing with the arsenic pollution,the selenium pollution in the capsicum and corn may be beneficial for the people eating the capsicum and corn roasted by coal-combustion.

0.05). Conclusion The present method has many advantages such as simplicity of operation,rapidity,better accuracy for the accurate quantitative analysis of urinary manganese.

Objective To investigate and analyze nasal carriage of bacteria in medical staff and antibiotic susceptibility. Methods All study participants underwent swabbing of the anterior 1.5 cm of the nasal vestibule of both nares with a sterile swab,and did drug sensitivity test Apr.-Oct.,2007. Results In 41.08% of all samples (125/299),136 pathogenetic bacteria were isolated. Klebsiella pneumoniae,Staphylococcus aureus and Enterobacter aerogenes were the prominent bacteria,of which showed the resistance for more than three kinds of antibiotics were 35,accounting for 25.73% of all isolates,10 strains of Methicillin-resistant Staphylococcus (MRS) were detected. Conclusion The nasal carriage of bacteria and antibiotics resistance in medical staff in Tianjin should be paid attention to,for it may an important factor in the control of infection in hospitals.

Lead is a kind of poisonous heavy metal which is widely existed in our environment. It is so harmful for children’s health. The whole society has paid much attention to this problem all the time. Blood lead level is an important index which can measure how seriously children have been exposed to lead. By consulting the papers on the studies of children's blood lead levels,the sources and influencing factors of blood lead levels of children in China were reviewed in the present paper,meanwhile,some suggestions were provided to decrease the lead contact probability and improve children's health.

Perchlorate is a new emerging environmental pollutant that is very stable and persistent,and it can diffuse rapidly in the environment. The environmental problems caused by perchlorate have attracted a great attention from many environmental scientists. However,up to now,a few reports on perchlorate pollution have been reported in China. In this paper,for perchlorate as an environmental pollutant,the sources,characteristics,detecting methods and toxicological effect on human body were reviewed,and the further research topics were presented.

Objective To investigate the acaroid mite pollution in houses in Huaibei area,Anhui province and to prevent allergic diseases caused by acaroid mites. Methods The samples of acaroid mites were collected from the houses,hotels and undergraduate dormitories,then the acaroid mites were separated,classed and counted. Results Fifteen kinds of acaroid mites were detected from the samples,belonging to 5 families,11 genera. The analysis showed that average density of acaroid mites in the common houses ranked the first,32.5. The values of the species richness index R was 1.36,the species diversity index was 2.16,the species evenness index was 0.9. Conclution The density of acaroid mites in the common houses is higher in Huaibei area and the effective measure should be taken to control the acaroid mites.

Objective To understand the water source type,the water supply way and drinking water quality in the pastoral areas in Qinghai Province. Methods One hundred and thirteen water samples in 11 counties were collected in the rainy season in 2006 and the water samples were tested according to the methods in Analytical Methods for Water and Sanitary Standard for Drinking Water Quality (2001),Sanitary Standard for Drinking Water Quality(2001). Results 1 741 231 population were investigated,the population consuming centralized water supply and dispersed water supply were 1 013 283(58.19%) and 727 948(41.8%) respectively. The population of drinking underground water occupied 76.4%,of which,drinking spring water occupied 83.2% and drinking well water occupied 4.6%. The population of drinking ground water occupied 23.6%,of which,drinking river water occupied 53.6%,drinking lake water occupied 0.2%. There were 638 centralized water supply plants,of which,only 11 water plants had complete water treatment. The dispersed water supply was consisted of manpower(84.7%),handpump(9.8%) and machine(5.5%). 51 of 113 water samples were up to standard,the overall eligible rate was 45.1%,of which the eligible rate of ground water was 25.9%,underground water was 51.2%,centralized water supply was 56.8%,dispersed water supply was 15.6%,showed the significant difference(P

Objective For drinking water deep treatment,this study compared the abilities of several common domestic products of activated carbon in virus removal from water through adsorption. Methods This study compared the abilities in virus removal of two types of granular activated carbon (GAC) materials (domestic product made of coconut shell) and one type of activated carbon fiber (ACF) material (domestic product made of mucilage glue-based ACF felt) under a fixed condition (phosphate buffered saline-PBS solution,pH =7.3,25 ℃) and the abilities of one of the above two GAC types under various conditions (before and after pretreatment,15-35 ℃,pH= 6.0-8.4,concentration of Ca2+ 0-500 mg/L,ionic strength 0-0.1 mol/L). The tested virus was the indicator phages obtained from sewage with an enterobacterium (Escherichia coli 285). Results The removal process with the GACs followed the first order kinetic model (R2: 0.83-0.99),whereas that of the ACF did not (R2: 0.44-0.64),with the rate constants of 0.505 3-2.606 8 (GACs) and 0.219 2-0.413 8 (ACF). Pretreatment (boiling for 2 h and then washing in deionized water) could both increase and decrease the removal effects,depending on the GAC sources. Different abilities in virus removal were found between the two GACs with their comparative outcomes depending on if they were subject to the pretreatment; higher levels of temperature,Ca2+ concentration,and ionic strength,and slight acidic and alkaline conditions favored virus removal. Calculation from the first order kinetic simulation showed that: the removal percentage within 15 min was around 30% with the highest 40% and the lowest 5%; and the maximum removal during the experimental period of 5 h reached 5-log. Although the amount (1 g) of the GACs used was ten times of that of the ACF (0.1 g),the measured values showed that the latter had faster initial removal rates than the former. Conclusion The three domestic products of activated carbon showed a large difference in their abilities to remove the viruses from water through adsorption with their comparative outcomes depending on the experimental conditions. If the short duration (about 15 min) currently employed in activated carbon treatment process is considered,it will be necessary to study the ways in promoting virus removal through adsorption onto the activated carbon materials of domestic products used in this experiment.