Concentrations of polycyclic aromatic hydrocarbons in samples of soil, feed and food collected in the Niger Delta region, Nigeria: A probabilistic human health risk assessment

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed compounds with two or more fused aromatic ring, being some of them classified as carcinogenic. In the present study, the concentrations of 16 PAHs and the sum of them (∑PAHs) were determined in samples of food, feed, plant and soil collected in six different heavily polluted areas (Choba, Khana, Trans Amadi, Eleme, Uyo and Yenagoa) of the Niger Delta Region (Nigeria). Principal component analysis (PCA) was then used to identify groups of variables (PAHs) and groups of samples that were the best in rendering the environmental pollution in that Region of Nigeria. In addition, PAHs food consumption and the derived carcinogenic risks were assessed in a probabilistic way. The highest ∑PAHs (mg/kg) were: 16.7 in cow meat, 8.06 in goat meat, 25.4 in chicken meat, 7.72 in fish, 28.70 in fish feed, 15.3 in chicken feed, 8.42 in plant, and 8.80 in soil. In most of the Nigerian areas, cooked cow meat, chicken and chicken feed presented the highest impact regarding PAHs contamination. The highest intake of PAHs was through meat consumption, with a very high and unassumable carcinogenic risk, which is quite above 10^-5 for some PAHs, including benzo [a]pyrene. The results of the present survey highlight the importance of reducing PAHs content in food, specially in meat, in the Niger Delta region.

Commercial Sex Work During Novel Coronavirus (SARS-CoV-2) Era in the Niger Delta Region: Relationships Between Knowledge, Preventive Practice, and Transmission Potential

BACKGROUND

Sex workers, like others, are facing economic hardships and anxiety about their health and safety due to coronavirus disease-2019 (COVID-19), an infectious disease caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Universally, most sex work has largely reduced, moved online, or undertaken covertly because of lockdown measures and need for social distancing to break the transmission of SARS-CoV-2. However, the ability of sex workers to protect themselves against COVID-19 depends on their individual and interpersonal behaviors and work environment. In this study, we sought to determine the relationships between COVID-19 knowledge, awareness and prevention practice (KAP) among female commercial sex workers (FCSW) in the Niger Delta region of Nigeria to inform the development of prevention interventions for this vulnerable population.

METHODS

Data used in this study were obtained from a cross-sectional survey of 604 FCSW operating in the Niger Delta region of Nigeria. We used descriptive and inferential statistics to assess their socio-demographic characteristics and COVID-19 KAP adopted against the novel coronavirus. Latent class analysis was used to systematically classify participants' attributes and behaviors into the most likely distinct clusters or risk groups.

RESULTS

The majority of the FCSW were singles (86.8%) of childbearing ages, 21-35 years (86.2%), with almost three quarters (73.2%) of them having sex with 3-4 clients per day during the COVID-19 pandemic. Overall, almost three quarters of the participants had both good knowledge and awareness about COVID-19 but less than half of them (41.1%) implemented good practice to prevent the spread of the disease. However, a highly significant and positive relationship was recorded between COVID-19 knowledge (r=0.90, p<0.0001) and awareness (r=0.65, p<0.0001), and preventive practice of FCSW, respectively. About 89.1% of the participants were not very familiar with the symptoms of COVID-19 (p<0.0001). Only 10.9% of the FCSW indicated that they wear facemask at all times, while 45.2% of them do not wear facemask during sexual intercourse with their clients (p<0.0001). Based on the FCSW attributes and behaviors, we identified three distinct clusters or risk groups (p<0.0001), namely, low-risk takers (Cluster 1), high-risk takers (Cluster 2) and very high-risk takers (Cluster 3) with latent class prevalence rates (γc) of 41.13% (95% CI: 37.26-45.10), 33.17% (95% CI: 29.53-37.02) and 25.71% (95% CI: 22.38-29.34), respectively.

CONCLUSION

Sex work has high transmission potentials for SARS-CoV-2 because of its operational nature, which does not permit social distancing, and thus, renders certain preventive measures practically ineffective. This is a major challenge in the fight against COVID-19 in this high-risk group and calls for the development of operational guidelines and targeted intervention strategies to help reduce the spread of COVID-19 in the Niger Delta region.

Stable isotopic composition of precipitation in a tropical rainforest region of the Niger Delta, Nigeria

The isotopic compositions of oxygen (δ ¹⁸O) and hydrogen (δ ²H) of precipitation were determined from three different locations in the western Niger Delta (Warri, Ughelli and Abraka) between 2014 and 2015. ¹⁸O and ²H in wet season precipitation were more depleted compared to the dry season. Similarly, d-excess computed for wet season precipitation is lower than that for the dry season. The δ ¹⁸O and δ ²H variations in precipitation suggest the effect of the convective system and north-easterly and south-westerly trade winds. The decrease in δ ¹⁸O and δ ²H was also observed in precipitation data of a continuous rain event of two successive days. The local meteoric water lines estimated for Warri, Ughelli and Abraka were δ ²H = 8.8 δ ¹⁸O + 9.1 ‰ (R ² = 0.93), δ ²H = 6.9 δ ¹⁸O + 10.7 ‰ (R ² = 0.98) and δ ²H = 7.9 δ ¹⁸O + 11.3 ‰ (R ² = 0.87), respectively. The Niger Delta regional meteoric water line of δ ²H = 7.7 δ ¹⁸O + 10.2 ‰ (R ² = 0.91) was derived from the monthly average from the three locations. The provided local meteoric water line for the Niger Delta from unweighted stable isotopic data represents a baseline for regional water resources studies.