Paul Musa Obadia

Introduction: Trace metals can negatively impact biological functions and brain development. Cognitive and neurobehavioral disorders in children are poorly documented in Haut-Katanga Province, an area with significant and multiple exposures to trace metals that can lead to the exacerbation of cognitive and behavioral disorders. Objective: This study aimed to characterize the behavior of schoolchildren linked to their cognitive performance in urban and rural environments. Methods: A cross-sectional pilot study was conducted on 52 schoolchildren aged 6 to 11 (22 from rural areas presumed less exposed to metals and 30 from Lubumbashi, DRC). This study employed NEPSY-II tests, the Strengths and Difficulties Questionnaire (SDQ-Tutor), ENA 2020 software and trace metal spectrometry assays. Statistical tests were carried out with SPSS-20 and Stata-18. Results: Our findings revealed a correlation between children’s malnutrition and low mother’s education. The “total difficulties score” was more prevalent in rural areas (73%) compared to urban settings (37%) p < 0.05), in contrast to the “negative impact of difficulties” (59% versus 57%, p > 0.05). Urban children demonstrated superior cognitive performance, particularly in “facial affect recognition” (8 versus 4, p = 0.013) and “inhibitory control” (6.5 versus 3, p = 0.032). As-U(urine), Cd-B(blood), Hg-B, Mo-U, Ni-U, Pb-U, Pb-B and Sb-U were elevated compared to references. In general, urban areas had higher metal levels than rural areas. Blood and urine metals showed a complex and significant relationship with behavioral difficulties or cognitive performance. Conclusions: The observed behavioral issues, cognitive performance deficits and their association with nutritional deficiencies and trace metal exposure suggest a multifactorial neurodevelopmental origin. These findings highlight the need for further research in the region.

Background: In a previous cross-sectional study to determine the prevalence and determinants of erectile dysfunction (ED) among artisanal mineworkers, we found a significant association between ED and consumption of locally produced plant-derived aphrodisiacs. Aim: We aimed to investigate the type and mode of consumption of aphrodisiacs, their possible health effects, and reasons for use among male workers in the Katanga province. Methods: We conducted a mixed method study, first doing a survey (March 2021) among a convenience sample of 127 artisanal miners and 122 collective taxi-drivers. Participants responded to the International Index of Erectile Function (IIEF) questionnaire and had measurements of serum urea, creatinine, hepatic enzymes, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides and sexual hormones. In a second qualitative phase, 16 participants, i.e., eight miners and eight drivers were interviewed. Results: Self-reported regular (at least once a week) consumption of aphrodisiacs was significantly more prevalent among taxi-drivers (75%) than among miners (47%). Mild-to-moderate and moderate ED were reported more frequently by aphrodisiacs consumers [20/152 (13%)] than non-consumers [6/97 (6%)]. Five types of plant-derived aphrodisiacs ( Zingiber officinale, Mitragyna stipulosa, Ocimum sp , Piper nigrum, Securidaca longepedunculata ) were consumed, via the oral or anal routes, sometimes together with alcohol. We found no evidence of nephrotoxicity, hepatotoxicity or disturbances in serum levels of sex hormones. Themes that emerged from interviews related to cultural perceptions about masculinity, with miners using aphrodisiacs to support failing erectile function, and taxi-drivers taking aphrodisiacs for preventing ED. Conclusion: We found a high prevalence of plant-derived aphrodisiacs use among working men in Katanga. While no serious adverse effects were identified, more ethno-botanical studies with isolation and rigorous identification of active constituents are needed to provide the poor population with correct information and to protect them against possible unwanted toxic effects.

The African Copperbelt is a site of intense artisanal and industrial mining and refining of copper and cobalt. We aimed to investigate factors that are possibly associated with erectile dysfunction (ED) in metal miners in the former Katanga province of the Democratic Republic of the Congo. In a cross-sectional study of 138 miners and 139 controls (bakers), we administered questionnaires to obtain sociodemographic and occupational data and to assess male sexual function (International Index of Erectile Function [IIEF]) and marital relation quality (Revised Dyadic Adjustment Scale). Furthermore, we measured trace metals in blood and urine, as well as testosterone and thyroid hormones in serum. Outcomes included the prevalence of questionnaire-derived ED and the relation of ED with individual characteristics, serum testosterone, and environmental factors. Miners were on average 4 years older than bakers (mean ± SD, 37.5 ± 6.9 vs 33.3 ± 5.7 years). Miners had significantly lower scores than bakers on the IIEF (median [IQR], 66 [49-73] vs 73 [66-74]) and the 3 domains of the Revised Dyadic Adjustment Scale (consensus, satisfaction, cohesion). Free testosterone was significantly lower in miners than bakers (ng/dL; 8.11 [6.90–10.10] vs 10.52 [8.83-12.58]; P ˂ .001). In miners, sex hormone–binding globulin correlated positively with blood Pb and urinary Cd. In a multivariable analysis, mild to moderate ED or moderate ED (IIEF–erectile function score ≤18) was significantly associated with having a mining-related job (adjusted odds ratio [aOR], 2.6; 95% CI, 1.3-5.3), work seniority ˃5 years (aOR, 2.3; 95% CI, 1.1-4.6), alcohol consumption (aOR, 2.8; 95% CI, 1.2-6.7), and aphrodisiacs use (aOR, 4.2; 95% CI, 2.2-8.0). Mediation analysis showed that marital relationship partially mediated the relation between work seniority >5 years in mining and ED. The high prevalence of ED found in artisanal mine workers indicates that work-related factors should be considered as possibly contributing, directly or indirectly, to sexual dysfunction in men. Strengths include being the first epidemiologic study documenting ED with validated questionnaires and its possible determinants, including exposure to toxic metals, among young artisanal miners vs a suitable control group. Limitations are the cross-sectional design with convenience sampling and absence of objective confirmation of ED. As compared with controls, miners reported poorer sexual function and lower quality of their marital relationship, and they had lower free testosterone levels, which may be due to their high exposure to trace metals.

Background: The consumption of energy drinks (EDs) is increasing in the general population, but little is known about the consumption of EDs among pupils in Africa. This study was designed to assess the consumption of EDs among pupils between 10 and 17 years of age and to assess average caffeine concentrations contained in EDs sold in Lubumbashi. Methods: We conducted a cross-sectional survey in five schools using a standardised questionnaire taken face-to-face. Samples of locally purchased EDs were analysed by High Performance Liquid Chromatography with Ultra-Violet spectrometry (HPLC-UV). Results: Of 338 pupils (54% girls), 63% reported having consumed at least one ED in the last week and 34% drank at least one ED a day. The cheapest ED was the most widely consumed. Among pupils having consumed at least one ED in the last week, 79% reported consuming it for refreshment and 15% to get energy. For those who reported not consuming EDs, 40% reported that their parents or teachers forbade them to drink EDs. Some (14%) teenagers, mainly boys, mixed ED with alcohol. The concentrations of caffeine measured in twelve brands of EDs ranged from 7.6 to 29.4 mg/100 mL (median 23.3), giving caffeine contents of 37.5 to 160 mg (median 90 mg) per can or bottle. The estimated daily intake of caffeine through EDs was between 51.3 mg and 441.3 mg among those consuming EDs regularly. Conclusion: Our study convincingly demonstrates that caffeine-containing EDs are not only consumed by youngsters living in affluent societies. We documented widespread regular consumption of EDs among (pre-)adolescent schoolchildren living in Lubumbashi, a large city of the Democratic Republic of Congo (DRC). In view of the global market expansion of caffeinated EDs, it is reasonable to suspect that similar surveys in other urban areas of sub-Saharan Africa would yield similar findings. Pricing and advertising regulations and education on EDs are necessary to limit the regular consumption of EDs among adolescents.

Objective Bakers are at high risk of rhinitis and asthma, but the prevalence of these occupational diseases is not well known in Sub-Saharan Africa. We investigated the prevalence of occupational rhinitis and asthma among industrial bakers in the former province of Katanga. Methods In a cross-sectional study conducted in eight towns from October 2018 to September 2019, we included 276 male workers from 18 industrial bakeries and 113 male controls (35 butchers and 78 bread sellers), all nonsmokers. Participants replied to a validated questionnaire (European Community of Respiratory Health Survey II), administered face to face, and performed spirometry at the work place. In 15 bakers with symptoms of work-related asthma, records of self-measured peak expiratory flow (PEF) 4 times per day during 4 weeks were analyzed by the OASYS (Occupational Asthma System) protocol. Results The bakers and controls did not differ by age (32.2 ± 7.3 y vs 32.8 ± 10.3 y). According to the questionnaire, work-related rhinitis and asthma were significantly more prevalent among bakers (31% and 5%, respectively) than among controls (2% and 0%, respectively). However, the groups did not differ significantly with regard to spirometric parameters. Based on PEF records, 10 out of 15 were positive for occupational asthma (OASYS score > 2.5), so the rate of occupational asthma was 3.6% in this study. Conclusion This first study in DR Congo demonstrates the existence of occupational rhinitis and asthma among industrial bakers in Katanga. Further epidemiological studies are needed to clarify the extent and risk factors of baker’s asthma in the area. In the meantime, advocacy and implementation of appropriate occupational hygiene measures are warranted to protect bakery workers in DR Congo.

Background: Air pollution is one of the world’s leading mortality risk factors contributing to seven million deaths annually. COVID-19 pandemic has claimed about one million deaths in less than a year. However, it is unclear whether exposure to acute and chronic air pollution influences the COVID-19 epidemiologic curve. Methods: We searched for relevant studies listed in six electronic databases between December 2019 and September 2020. We applied no language or publication status limits. Studies presented as original articles, studies that assessed risk, incidence, prevalence, or lethality of COVID-19 in relation with exposure to either short-term or long-term exposure to ambient air pollution were included. All patients regardless of age, sex and location diagnosed as having COVID-19 of any severity were taken into consideration. We synthesised results using harvest plots based on effect direction. Results: Included studies were cross-sectional (n = 10), retrospective cohorts (n = 9), ecological (n = 6 of which two were time-series) and hypothesis (n = 1). Of these studies, 52 and 48% assessed the effect of short-term and long-term pollutant exposure, respectively and one evaluated both. Pollutants mostly studied were PM_2.5 (64%), NO₂ (50%), PM₁₀ (43%) and O₃ (29%) for acute effects and PM_2.5 (85%), NO₂ (39%) and O₃ (23%) then PM₁₀ (15%) for chronic effects. Most assessed COVID-19 outcomes were incidence and mortality rate. Acutely, pollutants independently associated with COVID-19 incidence and mortality were first PM_2.5 then PM₁₀, NO₂ and O₃ (only for incident cases). Chronically, similar relationships were found for PM_2.5 and NO₂. High overall risk of bias judgments (86 and 39% in short-term and long-term exposure studies, respectively) was predominantly due to a failure to adjust aggregated data for important confounders, and to a lesser extent because of a lack of comparative analysis. Conclusion: The body of evidence indicates that both acute and chronic exposure to air pollution can affect COVID-19 epidemiology. The evidence is unclear for acute exposure due to a higher level of bias in existing studies as compared to moderate evidence with chronic exposure. Public health interventions that help minimize anthropogenic pollutant source and socio-economic injustice/disparities may reduce the planetary threat posed by both COVID-19 and air pollution pandemics.

Background: Thousands of artisanal workers are exposed to mineral dusts from various origins in the African Copperbelt. We determined the prevalence of respiratory symptoms, pulmonary function, and urinary metals among artisanal stone-crushers in Lubumbashi. Methods: We conducted a cross-sectional study of 48 male artisanal stone-crushers and 50 male taxi-drivers using a standardized questionnaire and spirometry. Concentrations of trace metals were measured by Inductively Coupled - Plasma Mass Spectrometry (ICP-MS) in urine spot samples. Results: Urinary Co, Ni, As, and Se were higher in stone-crushers than in control participants. Wheezing was more prevalent (p = 0.021) among stone-crushers (23%) than among taxi-drivers (6%). In multiple logistic regression analysis, the job of a stone-crusher was associated to wheezing (adjusted Odds Ratio 4.45, 95% Confidence Interval 1.09–18.24). Stone-crushers had higher values (% predicted) than taxi-drivers for Forced Vital Capacity (105.4 ± 15.9 vs. 92.2 ± 17.8, p = 0.048), Forced Expiratory Volume in 1 Second (104.4 ± 13.7 vs. 88.0 ± 19.6, p = 0.052), and Maximum Expiratory Flow at 25% of the Forced Vital Capacity (79.0.1 ± 20.7 vs. 55.7 ± 30.1, p = 0.078). Conclusion: Stone-crushers were more heavily exposed to mineral dust and various trace elements than taxi-drivers, and they had a fourfold increased risk of reporting wheezing, but they did not have evidence of more respiratory impairment than taxi-drivers.

Background. Public markets were exempted from the restrictive regulations instituted to limit the rapid spread of the COVID-19 pandemic in the Democratic Republic of the Congo (DRC). In the early stage of the pandemic, we assessed people’s knowledge, attitudes, and behavior on public markets towards COVID-19. Methods. We conducted a cross-sectional study from 16 to 29 April 2020 among sellers and customers frequenting the food sections of ten public markets in three large cities (Kolwezi, Likasi, and Lubumbashi) and one small town (Lwambo) of the former Katanga province. We administered a questionnaire on knowledge (about clinical characteristics, transmission and prevention) and on attitudes in relation to COVID-19. We also observed prevailing practices (hand-washing and mask-wearing). Results: Of the 347 included participants (83% women, 83% sellers), most had low socioeconomic status and a low level of education. Only 30% of participants had correct knowledge of COVID-19. The majority of the respondents (88%) showed no confidence in the government’s ability to manage the upcoming pandemic crisis. Nearly all respondents (98%) were concerned about the associated increase in food insecurity. Preventive practices were rarely in place. Conclusion: For an effective implementation of measures to prevent the spread of COVID-19 in Africa, appropriate health education programs to improve knowledge and attitudes are warranted among the population frequenting public markets.