"Evaluation of non-hazardous treatment efficiency of night soil in "" three-grille mode"" septic tanks" / 中国血吸虫病防治杂志

Objective To evaluate non-hazardous treatment efficiency of night soil in the three-grille mode septic tanks so as to give the evidence to government for policy-making. Methods One hundred and thirty normally runningthree-grille mode septic tanks were surveyed in five cities of Jiangsu Province in 2009. The fecal samples from first chamber and wastewater samples from third chamber were collected and examined for fecal coliform (FC) , parasite eggs including Schistosoma japonicum eggs, As-caris eggs and hookworm eggs, chemical oxygen demand ( COD), five-day chemical oxygen demand (BOD_5) and ammonia nitrogen (NH,-N) in lab. The data were analyzed by statistical software SPSS 13.0. Results The mean qualified rates of FC in the first chamber and third chamber of septic tanks were 3.1% and 100% respectively, showing significant difference (P <0.001). Hookworm eggs and Ascaris eggs were found in the first chamber of one and four septic tanks respectively and the density was one or two eggs in one hundred milliliter. The mean removal rates of FC, COD, BOD_5 and NH_3 -N were (99.96 ± 0.03) % , (60.69 ± 21.77) % , (60.13 ± 23. 20 ) % and (44. 14 ± 24.61) % , respectively. For the value of FC, COD, BOD, and NH_3 -N, there were significant difference between the first chamber and the third chamber (P_(FC) =0.000 1, P_(COD) =0.000 1, P_(BOD5) =0.000 1, P_(NH3-N) = 0.000 1, P < 0.001). Conclusion The treatment efficiency of septic tank could meet the sanitary standard for non-hazardous treatment of night soil, and it could use as a useful primary facility for human feces and urine treatment in rural areas.

Sanitary Clearance of Huaneng Qiaoqi Reservoir Bottom in Sichuan / 环境与健康杂志

Objective To assess the result of the sanitary clearance of Huaneng Qiaoqi reservoir bottom.Methods According to related standards and regulations,the sanitary clearance of Huaneng Qiaoqi reservoir bottom was conducted and the result was assessed in Oct.2006.Results 14 360 m~2 farm,417 excrement pits,390 latrines,1 599 graves were sanitarily cleaned. Deratization was carried out in reservoir bottom with Chinese area of 4 878 mu,rat density met the standard(

Survey of Current Status of Three-Chamber Septic Tanks at a Sampling Point in Chongqing / 环境与健康杂志

Objective To perform a hygienic assessment of the three-chamber septic tanks and analyze the efficiency of non- hazardous treatment of feces and the impact on the environment, so as to provide the reference for the three-chamber septic tanks improvement test. Methods From September 2007 to January 2008, the 20 latrines of residents and the three-chamber septic tanks were selected by simple random sampling method from A village of A town , Chongqing , as the investigation point,with suitable economic conditions,the status of the latrines with three-chamber septic tanks were surveyed, and the hygienic and environmental indicators of the third chamber feces samples were detected. Results After the implementation of the three-chamber septic tanks, the rural ecological environment was improved. The samples test showed that pH value was basically in the range of 8-9, the qualified rate was 85%, as for the other indicators, the qualified rates were generally lower. The qualified rate of chemical oxygen demand, ammonia nitrogen and total nitrogen was only 5% , five-day biochemical oxygen demand and total phosphorus was 10% , SS and the color was 15% , fecal coliform value of the samples were not qualified. Conclusion The management of the three-chamber septic tanks needs to be improved. If the liquid dung of septic tanks was directly discharged, it will cause secondary environmental pollution.So it should be deeply treated.

Effectiveness of Improvement of Latrines on Disease Prevention in Countryside / 环境与健康杂志

ve To explore the effectiveness of non-hazardous treatment of excreta on control of intestinal infectious diseases and parasitosis. Methods The popularization rate of sanitary latrines, the non-hazardous treatment rate of excreta, the prevalance rate of B-class intestinal infectious diseases and infectious rate of worm eggs were sta-tistically analyzed. Results With the increasing popularization rate of sanitary latrine and the non-hazardous treat-ment rate of excreta, the prevalance rates of 3 kinds of intestinal infectious diseases (dysentery, typhoid and hepatitis) decreased from 175.14/100 000 in 1991 to 57.78/100 000 in 2 000 namely decreased 67.01% . The infectious rates of helminth eggs decreased from 76.88% in 1991 to 22.16% in 2000 namely decreased 71.17%. Conclusion Non-hazardous treatment of excreta presented obvious effectiveness on disease prevention, which should be widely popularized in countryside.

EFFECT OF NON-HAZARDOUS TREATMENT OF TWO-GRILLE LATRINES / 中国血吸虫病防治杂志

Objective To understand the e ff ectiveness of parasite ova sediment and non-hazardous treatment of two-grille la trines. Methods Two-grille latrines were recon n oitered in the field according to the non-hazardous treatment criteria, and th e sediment of parasite ova, the value of fecal coliform bacteria, NH 3-N, CODcr of the samples from the Grille 1 and Grille 2 of latrines were detected.Results The structure of some two-grille latrines was n o t in accord with the non-hazardous treatment criteria.Parasite ova were detecte d from the Grille 2 of one latrine. Six of 16 latrines were not eligible for non -ha zardous treatment according to the value of fecal coliform bacteria in Grille 2. Conclusion It is not suggested to popularize th e two-grille latrine yet, but it can be used as an interim form for excrement n on-hazardous treatment in rural areas. [

Investigation on Quality of Construction and Sanitation of Double-urn-and-single-funel Latrines in Countryside of Zhengzhou / 环境与健康杂志

Objective To understand the quality of construction and sanitation of double_urn_and_single_funel(DUSF)latrines widely popularized in He'nan province and its current problems.Methods The qualities of contruction and sanitary management of 1269 DUSF latrines were investigated in countryside of Zhengzhou.Results The total qualified rate of the construction quality was 86.9% for 1269 observed DUSF latrines.The constituent ratios of latrines with good,moderate and bad sanitary management were 43.4%,33.4% and 23.2% respectively.The percentages of the latrines with auxiliary facilities such as flax brushes,tolet paper collectors and water storage tanks were 66.5%,67.3%and 39.4% respectively.Conclusion The quality of construction of DUSF latrines in countryside of Zhengzhou was qualified on the whole.But the sanitary management and maintenance of DUSF latrines should be improved further.