Background: The global consumption of herbal medicine is increasing steadily, posing an extinction risk to medicinal plants. Uganda is among the top ten countries with a high threat of herbal medicine extinction, and Traditional Medicinal Knowledge (TMK) erosion. This might be attributed to the inadequate documentation, plus many more unclear hindrances. In this study, plant species used to treat human diseases in Butaleja district in Eastern Uganda and their associated TMK were documented. The conservation methods for medicinal plants were also evaluated. The rationale was to support the preservation of ethnopharmacological knowledge. Methods: Data were collected from 80 herbalists using semi-structured questionnaires, from July 2020 to March 2021. Additionally, guided field walks and observations were conducted. Quantitative indices such as, use categories and informant consensus factor (ICF) were evaluated to elucidate the importance of the medicinal plants. Data were analyzed using STATA version-15.0 software. Results: In total, 133 species, belonging to 34 families and 125 genera were identified. Fabaceae (65%), and Solanaceae (29%) were the dominant families. Leaves (80%), and roots (15%), were the commonest parts used in medicinal preparations; mostly administered orally as decoctions (34.6%) and infusions (16%). The commonest illnesses treated were cough (7.74%), gastric ulcers (7.42%), and malaria (4.52%). The informant consensus factor was high for all disease categories (≥ 0.8), indicating homogeneity of knowledge about remedies used. Only 73% of the respondents made efforts to conserve medicinal plants. The commonest conservation strategy was preservation of forests with spiritually valued species (100%), while compliance with government regulations was the rarest (4.5%). Overall, efforts to stop the extinction of medicinal plants and TMK were inadequate. Conclusion and recommendations: There was enormous dependency on a rich diversity of medicinal plant species and TMK for healthcare and income generation. The potential for medicinal plant biodiversity loss was evident due to habitat destruction. Inclusion of traditional cultural norms in conservation strategies, and laboratory-based efficacy tests for the species identified are necessary, to promote the conservative and utilization of validated herbal medicines and TMK in rural settings.

Mercury (Hg) has been used for millennia in artisanal and small-scale gold mining (ASGM) to extract gold from ore as an amalgam that is heated to recover gold. Since there is hardly any sustainable technology that can be used to recover it, the vast percentage of released Hg finds its way into the environment. Currently, ASGM is the largest source of mercury pollution on Earth. Mercury (Hg) is listed among the top 10 most harmful metals by the World Health Organization (WHO), and it is known to cause several neurological disorders in humans. Thus, Hg levels in environmental systems surrounding pollution hotspots such as ASGM mines need to be monitored to ensure their proper management and protect vulnerable ecosystems and human health. This work was aimed to study the level of Hg pollution in soils and plants thriving around ASGM mines in Eastern Uganda and to evaluate the Hg phytoremediation potential of the plants. The total Hg contents were determined for soils, food crops and wild plants growing around ASGM mines. The results for the pH, organic carbon (OC) and electric conductivity (EC) of the soils in the study area were comparable to those of the control soils. The soils in the studied ASGM areas exhibited high Hg concentrations ranging between 723 and 2067 folds more than those of the control soils. All soils were moderately to heavily contaminated according to geoaccumulation (Igeo) index values that ranged between 1.16 and 3.31. The results of this study also showed that the food crops and wild plants accumulated Hg levels that were above the 20 ng/g (0.02 ppm) permissible limit. This study revealed relatively higher levels of Hg in the aerial parts of the plants compared with the underground organs, which can be attributed to Hg deposition, entry through stomata and foliar adsorption. Mercury levels in 47% of the food crop samples were above the FAO/WHO permissible mercury limit of 0.5 µg/g. Similarly, medicinal plants accumulated Hg to levels that were several folds higher than the 0.2 ppm permissible limit of mercury in herbal materials of Canada. Interestingly, this study showed that some wild plant species, especially sedges, exhibited relatively higher levels of mercury accumulation than others thriving in the same environment, an indication that such plants could be utilized in the phytoremediation of Hg-contaminated sites.

Background: There has been a lot of debate on genetically modified (GM) crops both globally and locally in Uganda. Whereas some of the debates have been informed by scientific research, many are not. The level of acceptance and attitudes of people towards GM crops is a function of their knowledge. However, there is a paucity of studies on the knowledge and attitudes of Ugandans on GM crops. This study aimed to assess the level of knowledge of GM crops in Uganda. Methods: We carried out a mixed methods study in September 2021 in Bushenyi, Jinja and Wakiso districts. We conducted 18 focus group discussions (FGDs), 13 key informant interviews (KIIs) and 698 quantitative interviews. The quantitative interviews were conducted using structured questionnaires. The FGD and KI interviews were audio recorded and transcribed verbatim. The qualitative data were analyzed using framework analysis and the quantitative data were analyzed using modified Poisson regression to identify factors associated with the level of knowledge of GM crops in STATA 15. Results: Out of the 698 respondents interviewed, only 273 (39.1%) had ever heard of GM crops. About 204 (74.7%) of the 273 respondents reported having a moderate–high understanding of GM crops and 62.3% (170) of the respondents further reported that GM crops are harmful to their health and environment, despite some of their intrinsic benefits, such as high productivity, improved income and resilience to pests and diseases. In addition, Out of the 698 respondents interviewed, only 37.7% were wary of the possibility of the emergence of super pests due to the development of resistance to some GM crops. Conclusions: Most of the community members do not have adequate knowledge about GM crops, hence, there is need for sensitization and legislation on GM crops before their release to the public.

Introduction: Destruction of vegetation resources emanating from deposition of mine wastes is a serious environmental problem. Conventional plant species restoration methodologies are costly and feasible only