4 research outputs found
Drinking water quality and identification of fluoritic areas in Machinga, Malawi
There is prevalence of dental fluorosis in certain parts of Machinga District that can be attributed to elevated drinking water fluoride content in the areas. Therefore, it is important to know the actual quality of water within the district and identify specific fluoride endemic areas that may require immediate adoption of remedial measures to manage the water resource and thus protect consumers. In this study, drinking water samples were collected from boreholes and pipes at 23 sampling sites, mostly villages within the district, for fluoride and other water physicochemical parameters during dry and rainy seasons of 2004 and 2005 respectively. Fluoride endemic sites were identified from the fluoride data. A survey of school children was also done in order to examine symptoms of dental fluorosis. Levels of fluoride ranged from 0.35 to 10.30 mg/L with 70 % of the sites sampled indicating levels above the World Health Organization (WHO) guideline of 1.50 mg/L. Fluoride endemic areas were identified as those villages around Mtubwi F.P School and Liwonde L.E.A School. This finding was supported by the prevalence of a high proportion of dental fluorosis in standard 3 and 4 pupils in these two schools. Values of pH ranged from 6.70 to 9.37; electroconductivity from 1950 to 31000 mS/cm; turbidity from 0.00 to 2.41, Formazin Turbidity Units (FTU); phosphates from 0.0 to 1.88mg/L; nitrates from trace to 58 mg/L; hardness from 1.08 to 276 mg CaCO3/L; sulphates from 6.09 to 109.98 mg/L; chlorides from 0.003 to 0.576 mg/L; carbonates from 2.01 to 85.30 mg/L and bicarbonates from 51.02 to 677.52 mg/L. Correlation of fluoride with other drinking water parameters was assessed using simple graphical methods. Positive correlation was observed between concentrations of fluoride with pH, total dissolved solids and carbonates, while phosphates correlated negatively with the fluorides. No correlation was observed between concentrations of fluoride with nitrates, electroconductivity, total hardness, carbonates and chlorides.Keywords: Machinga; fluoride; fluorosis; physicochemical parameter
Chemical variation and insecticidal activity of Lippia javanica (Burm. F.) Spreng essential oil against Sitophilus zeamais Motschulsky
Lippia javanica (Burm. f.) Spreng is used commercially as an herbal tea and medicinal plant in sub-Saharan Africa. Here we investigated the chemical variation and pesticidal potential of L. javanica essential oils against a major stored product pest, Sitophilus zeamais Motschulsky. We identified two morphologically distinct varieties of L. javanica growing at different locations in Malawi. Perillaldehyde was the major constituent in oil of L. javanica var. javanica while myrcenone (ipsdienone) was the major compound in oils of L. javanica var. whytei. Myrcene, linalool, carvone, β-caryophyllene and germacrene D were identified as the other most significant components in oils from both varieties. The yields of oil and the chemical composition also varied significantly with time of harvest during the season in both cases. In contact toxicity tests against S. zeamais, oils from both varieties were active. However, whereas perillaldehyde, linalool and carvone, components of the oil of L. javanica var. javanica, were all toxic against adult S. zeamais, myrcenone, the main component of oil from L. javanica var. whytei, was not. The oil from L. javanica var. javanica also showed some fumigant toxicity against S. zeamais. The high efficacy of L. javanica oil against S. zeamais suggests it is suitable to be used as a botanical insecticide to control S. zeamais in stored maize. However, further research is required to optimise and standardise the variety and harvest time to be recommended and to evaluate its activity against S. zeamais and other storage insect pests under farm conditions before it can be adopted by farmers more widely
Chemical variation and Insecticidal Activity of Lippia javanica Essential Oil against Sitophilus zeamais.
Evaluation of the implementation of the reaching every district approach in routine immunisation in Lusaka District, Zambia
Background: In 2003, the Government of Zambia in collaboration with implementing partners in immunisation introduced the Reaching Every District (RED) strategy to improve immunization coverage. The aim of this study is to evaluate the implementation of the RED strategy in Lusaka district.Methods: A questionnaire was administered among health centres in charge of all governmental health clinics in Lusaka districts (N = 27). RED implementation was quantified by calculating a RED implementation score (IS) for each of the RED components on a scale of 0 (low implementation score) to 5 (high implementation score).Results: The mean overall RED implementation score was 3.5. The RED component of linking services with community and re-establishing outreach were the two weakest components.Conclusions and recommendations: This evaluation showed that there are a number of elements of the RED strategy which are well implemented; however, some elements need further improvements. There is need for more research on the implementation of the RED strategy in Zambia in order to identify bottlenecks for improving immunization coverage at larger scale and a wider participation.Keywords: RED, Immunization, training, outreach, community links, monitoring, planning, supportivesupervision