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The large surface area of Lake Victoria (about 68,800 km2) makes it vulnerable to high atmospheric deposition of chemical pollutants. We present measurements of polychlorinated biphenyls (PCBs) from the lake's atmospheric environment. High volume air (24 h) samples were collected within the northern Lake Victoria watershed in Uganda over two periods; 1999–2004 [at Kakira (KAK) and Entebbe (EBB)] and 2008–2010 (at EBB only). Precipitation samples were also collected monthly during the 2008–2010 period at EBB. Analysis for PCBs was done using GC-μECD in a dual column approach. The ranges of ΣPCB concentrations in the KAK air samples were 154–462 pg m−3 (KAK 1999–2000), 26.7–226 pg m−3 (KAK 2003–2004), 27.0–186 pg m−3 (EBB 2003), 46.8–174 pg m−3 (EBB 2004), 19.2–128 pg m−3 (EBB 2008), 45.8–237 pg m−3 (EBB 2009) and 65.6–244 pg m−3 (EBB 2010). The di-, tri-, tetra- and penta-PCBs were predominant in air sample sets while the tetra- and penta-PCBs were predominant in precipitation samples. The mean flux of ΣPCBs in the precipitation samples was 26.9 ng m−2 (range of 14.8–41.5 and median of 27.5). Concentrations at EBB were lower than those reported elsewhere for urban sites in the East and Central African region. Multivariate analysis and analysis of air mass movements suggested influence of combustion sources on the PCB profiles from the region, especially, from the major East African urbanized regions.

In Uganda, malaria has been ranked as a leading cause of morbidity and mortality with Apac District having one of the highest transmission rates. The objective of this study was to assess the use of medicinal plants in preventing and treating malaria and to determine the traditional concept of malaria in Cegere Sub-County, Apac. A snowball sampling method was used to work through a network of informants. Ninety respondents, including traditional healers, were interviewed using focus group discussions and questionnaires. Twenty plant species from 15 families were used for preventing and treating malaria. Most of the plants were herbs (50%), and leaves (64%) were the most frequently used parts. Schkuhria pinnata (Lam.) Kuntze ex Thell. was the most frequently cited plant for treating malaria, mentioned by 77% of the respondents. Traditionally, malaria was known as atipa and was treated ritually. Fewer medicinal plant species were used to treat malaria in Apac compared to other parts of Uganda.

Information on historical deposition of persistent organic pollutants (POPs) for African lakes is very limited. We investigated historical deposition trends and sources of POPs in sediment cores from Lakes Victoria (SC1), Bujuku (Buju2) and Mahoma (Maho2). The latter two lakes are situated in the Rwenzori mountain range in western Uganda. SC1 was taken from a central depositional area within the Ugandan part of the lake. Profiles in Buju2 and Maho2 were used as a reference for historical atmospheric deposition. For the post-1940 sediment deposits in SC1, average focusing factor-adjusted fluxes (FFFs) of ΣDDTs, polychlorinated biphenyls (ΣPCBs), hexachlorocyclohexanes (ΣHCHs) and chlordanes (ΣCHLs) were 390, 230, 210 and 120 ng m(-2) yr(-1). Higher fluxes of ΣDDTs, ΣPCBs, and ΣCHLs were observed in Buju2 and Maho2. The average FFF of HCB in Buju2 was the highest while the values for Maho2 and SC1 were similar. The endosulfan FFFs in SC1 were lower than in the alpine lake cores. Generally, Buju2 was a better reference for historical atmospheric deposition of POPs than Maho2 probably due to distortion of the latter's profile by Lake Mahoma's forested catchment. Profiles of p,p'-DDE, ΣCHLs and HCB in SC1 were consistent with atmospheric deposition while profiles of PCBs and HCHs were indicative of particle-bound loadings from additional sources. Profiles of endosulfans, DDTs, and chlordanes were consistent with influence of other factors such as anoxia, and dilution. Further studies of spatial resolution of historical deposition, especially in near-shore deposition areas of the lake are recommended.

Pres de 10 % des 80 chimpanzes composant la communaute de chimpanzes sauvages (Pan troglodytes schweinfurthii) de Sebitoli, dans le parc national de Kibale en Ouganda, presentent des phenotypes faciaux singuliers. L'etiologie de cette malformation est inconnue mais des etudes menees sur des groupes de macaques au Japon et a Hong Kong severement affectes par des anomalies des membres (jusqu'a 17 % des individus dans les groupes de macaques approvisionnes en nourriture potentiellement contaminee par des pesticides) suspectent une origine congenitale liee aux agents teratogenes contenus dans les pesticides. Une etude a donc ete menee du 06/03/14 au 15/05/14 afin de mieux connaitre les consequences physiologiques d'une telle malformation chez les chimpanzes de Sebitoli et leur exposition aux pesticides utilises autour de la zone du parc. Des observations de type ''focal sampling'' d'une et dix minutes ainsi que des observations de type ''scan sampling'' toutes les minutes ont ete effectuees sur les chimpanzes sauvages (27 individus dont 8 atteints de dysplasie faciale) en cours d'habituation par le « Sebitoli Chimpanzee Project » dirigee par S. Krief. Afin de tester l'hypothese d'une origine de la malformation liee a la pollution environnementale, des entretiens ont ete effectues aupres d'agriculteurs cultivant du mais et/ou du the a la bordure du parc. Comme les chimpanzes pillent le mais et pratiquent la geophagie, 123 echantillons de sol, sediment et de mais ont ete recoltes dans le but de mesurer les residus de produits chimiques. Les travaux ethnographiques et agronomiques ont ete effectues en collaboration avec l’equipe du departement de chimie de l'universite de Makerere (Kampala, Ouganda). Les observations conduites sur les chimpanzes ont permis de mettre en evidence un gene respiratoire associee a la dysplasie faciale observee : les individus a dysplasie faciale ouvrent plus souvent la bouche que les individus normaux lors des activites de repos, de deplacement et d'alimentation, et leur rythme d’ingestion d’aliments sauvages (Ficus dawei) est egalement plus lent. Les entretiens ont revele que l'usage local de produits chimiques etait principalement freine par leurs couts eleves, y compris pour les petites exploitations de the. Cependant, la culture de the consomme une quantite importante d'herbicides et de fertilisants, ce qui entraine probablement une pollution environnementale sur le long terme. Au total, cinq produits chimiques ont ete designes candidats pour une cause toxique intra-uterine de la malformation faciale des chimpanzes. Mais excepte le mancozeb qui ne semble pas avoir d'effets teratogenes, il est impossible de cibler plus precisement un intrant chimique parmi ceux utilises regulierement a savoir : un fertilisant (le NPK), un insectide (la cypermethrine) et deux herbicides (le 2,4-D et le glyphosate). Les analyses en cours des echantillons de sol, sediments et mais recoltes permettront d'evaluer l'exposition reelle des chimpanzes aux pesticides et plus largement, l'exposition de la population humaine et de la faune et flore du parc national.

Ethnopharmacological relevance The plant Neoboutonia macrocalyx has been reported in traditional medicine to be used in the treatment of malaria. Aim of the study To study the in vitro antiplasmodial activity of compounds from the stem bark of Neoboutonia macrocalyx. Materials and methods Compounds were extracted and purified from stem bark of Neoboutonia macrocalyx and their structure identified and confirmed by spectroscopic methods. The crude ethyl acetate extract, aqueous extract and the isolated compounds were evaluated for antiplasmodial activity against the chloroquine sensitive Sierra Leone I (D6) and chloroquine-resistant Indochina I (W2) strains of Plasmodium falciparum. Results Chemical investigation of the ethyl acetate extract of Neoboutonia macrocalyx bark resulted in the identification of one new diterpenoid; neoboutomacroin (1) in addition to the four known compounds which included, a phenanthrene; 3,6-dihyroxy-1,7-dimethyl-9-methoxyphenanthrene (2), a sterol; 3-O-Acetyloleuritolic acid (3) and two diterpenoids; simplexin (4) and montanin (5). Compounds 1 and 5 displayed good antiplasmodial activity of IC50 values less than 10 μg/mL against both strains. However, all the compounds tested displayed high cytotoxic activity against MRC5 cell line with IC50 less than 10 μM. Conclusions Despite an indirect in vitro antiplasmodial activity of some compounds isolated from the stem bark of Neoboutonia macrocalyx, the identification of these bioactive compounds indicates that they may play a role in the pharmacological properties of this plant.