Polychlorinated biphenyls in canned sardines in Nigeria and health risk assessment

Safety evaluation of organochlorine pesticides and polybrominated diphenyl ethers in imported canned fish in Nigeria

Organochlorine pesticide (OCP) and polybrominated diphenyl ether (PBDE) concentrations were measured in thirty popular brands of imported canned fish (mackerel, sardines, and tuna) in Nigeria to ascertain potential threats to humans arising from their consumption. The Σ20 OCP concentrations in mackerel ranged from 0.47 to 7.36 ng g-1, while those of tuna and sardines varied from 1.06 to 2.19 and 0.11 to 12.7 ng g-1, respectively. The Σ39 PBDE concentrations in mackerel varied from 0.06 to 4.21 ng g-1, while those of tuna and sardines ranged from 0.19 to 3.18 and 0.04 to 8.26 ng g-1, respectively. The estimated daily intake (EDI) of OCPs and PBDEs from ingestion of the canned fish by adults and children were in the magnitude of 0.03 to 17.6 ng kg-1 bw day-1 and 9.9 × 10-3 to 11.5 ng kg-1 bw day-1 respectively. The hazard index (HI) and total cancer risk (TCR) values for OCPs and PBDEs from ingestion of the canned fish were less than 1 and 10-6, respectively. The dietary intakes of OCPs and PBDEs from these brands of canned fish by adults and children result in no adverse non-cancer and cancer risks.

Measurement of polychlorinated biphenyls in different high consumption canned foods, using the QuEChERS/GC-MS method

Polychlorinated biphenyls (PCBs) are organic pollutants containing chlorine, which can be carcinogenic to humans. The current research focused on the heart risk and determination of PCBs levels in canned foods using the modified QuEChERS (fast, easy, cheap, effective, resistant and safe) method and gas chromatograph/mass spectrometer (GC-MS) technique. In this study, LOD (limit of detection), LOQ (limit of quantification), and recovery ranged from 0.06 to 0.32, 0.18 to 1.07 ng/g, and 97.05 to 102.5 %, respectively. In canned foods, the highest median of PCBs was PCB 52 (0.27 ± 0.20 ng/g fat) and the lowest median were PCB 28 and 138 (not detected in samples). Also, the maximum median of PCB 28, 52, 101, 138, 153, and 180 were detected in eggplant samples (0.06 ng/g), haricot samples (0.49 ng/g), eggplant samples (0.36 ng/g), eggplant samples (0.19 ng/g), eggplant samples (0.11 ng/g) and lentiform samples (0.66 ng/g), respectively. The median PCBs levels of oral exposure were estimated to be in the range of 9.80E-07to 4.30E-05 ng/g.d for all population groups, which were meaningfully lesser than the Tolerable daily intake value. The Monte Carlo simulation (MCS) outcomes indicated that the rank order of PCBs in adults based on incremental lifetime cancer risk (ILCR) was Lentiform (7.05E-8) > canned fish (5.73E-8) > Eggplant (5.38E-8) > Haricot (4.33E-8) > pasta source (2.06E-8); and in children was Lentiform (3.40E-7) > canned fish (2.72E-7) > Eggplant (2.44E-7) > Haricot (2.06E-7) > pasta source (9.83E-8). The median values of the ILCR induced oral exposure for all groups were within safe limits (lower than 10-6). The heat map and multivariate principal component analysis (PCA) showed significantly different contributions of PCBs profile in samples as the PCA axis scores were correlated with the type of cans. Based on the obtained outcomes, it can be concluded that the PCBs of canned food do not potential health risks to Iranian consumers.

Environmental endocrine disruptors and pregnane X receptor action: A review

The pregnane X receptor (PXR) is a kind of orphan nuclear receptor activated by a series of ligands. Environmental endocrine disruptors (EEDs) are a wide class of molecules present in the environment that are suspected to have adverse effects on the endocrine system by interfering with the synthesis, transport, degradation, or action of endogenous hormones. Since EEDs may modulate human/rodent PXR, this review aims to summarize EEDs as PXR modulators, including agonists and antagonists. The modular structure of PXR is also described, interestingly, the pharmacology of PXR have been confirmed to vary among different species. Furthermore, PXR play a key role in the regulation of endocrine function. Endocrine disruption of EEDs via PXR and its related pathways are systematically summarized. In brief, this review may provide a way to understand the roles of EEDs in interaction with the nuclear receptors (such as PXR) and the related pathways.

Organochlorine pesticides and polychlorinated biphenyls in city drains in Makurdi, central Nigeria: Seasonal variations, source apportionment and risk assessment

A study of seasonal variation, sources and potential risks of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in open city drains in Makurdi, Central Nigeria was carried out. OCPs and PCBs were quantified using gas chromatograph-mass spectrometer. The total (∑₈OCPs) concentrations (ngL^-1) of OCPs in water was 2.99 with a mean ± SD of 0.75 ± 0.12 during wet season, while during dry season, the values were 11.43 and 2.86 ± 1.54 respectively. In sediment, the total concentration (ngg^-1) of OCPs was 5270.66 with a mean ± SD of 1756.89 ± 450.01 during wet season and a total concentration of 5837.93 and the mean ± SD of 1945.98 ± 646.04, during dry season. Source apportionment of OCPs suggested historic application of the pollutants. The total (∑₇PCBs) concentration (ngL^-1) of PCBs in water was 0.24 with a mean ± SD of 0.03 ± 0.02 during wet season and a total concentration of 0.61 with a mean ± SD of 0.09 ± 0.11 during dry season. The total concentration (ngg^-1) of PCBs in sediment was 37.88, mean ± SD of 5.41 ± 5.93 during wet season and a total of 47.07 and mean ± SD of 6.72 ± 7.27 during dry season. Ecological risk assessment based on effect range low (ERL) and effect range median (ERM) or threshold effect level (TEL) and probable effect level (PEL) that ecological risks were possible for some OCPs in this study, which calls for source control and remediation of the affected sites. Toxicity equivalency (TEQ) of PCB-118, the dioxin-like congener, indicated that it was most harmful to humans/mammals followed by birds, then fish.

Polychlorinated biphenyls and polychlorinated dibenzo-p-dioxins and furans in imported canned fish in Nigeria and risk assessment

Concentrations of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) were measured in imported canned fish such as mackerel, sardine and tuna to evaluate the risk relating to human consumption of these products. Gas chromatography-mass spectrometry (GC/MS) was used to evaluate the concentrations of PCBs and PCDD/Fs in the samples. The ∑28 PCB concentrations in the canned mackerel, tuna and sardine ranged from 0.33 to 9.48 ng g ^-1, <LOQ to 8.8 ng g^-1 and <LOQ to 15.1 ng g^-1, respectively, while the ∑14 PCDD/Fs concentrations varied from 0.06 to 4.70 ng g^-1 for mackerel, 0.72 to 9.43 ng g^-1 for tuna and not detected to 22.0 ng g ^-1 for sardines. Health risk analysis suggests that ingestion of these samples could lead to adverse non-carcinogenic and carcinogenic risks over a lifetime.

Concentrations, sources, and exposure risk of polychlorinated biphenyls in soil profiles of the floodplain of the lower reaches of the River Niger, Nigeria

The concentrations of 28 polychlorinated biphenyls (PCBs) were determined in soils collected at three depths from thirteen different sites along the floodplain of the lower reaches of the River Niger (LRRN) in Nigeria. The aim of the study was to provide data on the levels of contamination, sources of the contaminants, and risks to the ecosystem and humans. Soil samples were Soxhlet extracted with a solvent mixture of dichloromethane (DCM)/n-hexane and cleaned up on a column packed with Florisil and silica gel. The PCBs in the samples were quantified by gas chromatography-mass spectrometry. The Ʃ28 PCB concentrations in the floodplain soils varied between not detected (nd) and 11,151 ng g^-1 for different sampling sites and depths. The PCB concentrations and homologue distribution patterns in soil profiles of the floodplain of the LRRN showed remarkable differences with respect to sites and depths. The results obtained were used to evaluate the ecological and human health risks, which indicated that there is a potential risk to organisms and humans from exposure to PCBs in these soil profiles. The source evaluation as determined by principal component analysis suggested that PCBs in these soil profiles came from burnt circuit boards, cable wires, use of paints, discharges from transformers, long-range migration, and deposition.

Food security and safety concerns in animal production and public health issues in Africa: A perspective of COVID-19 pandemic era

The impact of COVID-19 on food security can best be understood from the downturn on agricultural and other related economic activities which were almost brought to a total halt during the pandemic. The restriction of movement/lockdown policy instituted by various governments heavily affected local and national food production as farmers could not go to their farmlands. More so, there was price gouging on raw food items as local farmers were reducing cultivation and harvest because of their safety. The lockdown also affected the transportation of food products from farms and local companies to the market and across inter-state/province borders. Additionally, many human infections traceable to disease outbreak from animal origin suggest a great risk of exposure to infectious agents by live animal farmers. In combating this menace, local food production needs to be encouraged more, while measures should be put in place to facilitate farmer's participation in government regulations on enforcing biosecurity, health standards, disease monitoring, and surveillance practices.