Azhari O. Abdelbagi

Organochlorine levels in human blood from residents in areas of limited pesticide use in Sudan

Ninety-nine human blood samples were collected from the riverine region of northern Sudan and the traditional and mechanized rain-fed areas of western and eastern Sudan, representing areas of limited pesticide use in Sudan. Blood samples were analyzed for organochlorine pesticides by gas liquid chromatography (GLC) followed by electron-capture detection (ECD). p,p′-DDE (a metabolite of DDT), heptachlor epoxide, β-hexachlorocyclohexane (β-HCH), and dieldrin were detected in all locations surveyed. The level of total organochlorine burden was highest in the traditional rain-fed area, followed by the mechanized rain-fed area, and the riverine area. A highly significant correlation was observed between total organochlorine blood burden and the age of the donors (r = 0.608**).

Use of volatile oils of garlic to control the cowpea weevil Callosobruchus maculatus (Bruchidae: Coleoptera)

Cowpea weevil causes losses of 50–90% in cowpea after harvest. Control has relied on toxic agrochemical fumigants that are no longer available or are dangerous and relatively expensive, making its control difficult for most farmers. This study was initiated to investigate alternative control methods to synthetic pesticides, namely the suitable fumigation period and oil concentration of volatile oils of garlic, Allium sativum, were evaluated as a fumigant against adults of the cowpea weevil, Callosobruchus maculatus (Bruchidae: Coleoptera). Fumigation was carried out in small plastic cups (200 mL) and jute sacks (100 g) after several exposure periods (6–24 h). Insect recoveries were observed for 4 d. The volatile oils were tested at concentrations ranging between 0.1% and 20% (v/v). The oils were effective and caused significant mortalities to the test insects in cups at all concentrations tested. Garlic oil vapour penetrated through jute sacks and caused significant mortality to test insects. Recovery cases were negatively correlated to the dose. The 24 h LD50 and LD90 were 0.036% (equivalent to 175.78 μL volatile oils m−3) and 3.61% (equivalent to 17.63 mL volatile oils m−3), respectively, in the cups and jute sacks. The concentration 10% gave 100% mortality within 24 h of exposure.

Effect of radiation and/or traditional processings on antinutrients and HCl extractability of calcium, phosphorus and iron of sorghum cultivars

Whole flours of sorghum cultivars Dabar, WadAhmed and Karamaka were irradiated and then fermented and/or cooked. Tannin and phytic acid contents were assayed for all treatments. Traditional processings (fermentation and cooking) were significantly (P ≥ 0.05) decreased tannin and phytate of the cultivars and further reduction was observed when the flour was irradiated before processing for all cultivars. Radiation process alone had no great effect on tannin and phytate contents but when followed by traditional processing the reduction level was significant (P ≥ 0.05) for all cultivars. Radiation alone had no significant (P ≥ 0.05) effect in increment of total and extractable calcium (Ca). However, radiation followed by fermentation and/or cooking significantly (P ≥ 0.05) increased both total and extractable Ca. Total phosphorus (P) was not significantly (P ≥ 0.05) increased at all levels of radiation and/or processing but the extractable P was increased. Total iron (Fe) was not affected by radiation and/or processings but the extractable Fe was increased significantly (P ≥ 0.05) with the radiation dose for all cultivars.