No abstract

Lake Nokoué and Cotonou Lagoon are the most important and most productive continental freshwaters in Bénin, with an estimated fish production of over 2 tonnes per hectare in Lake Nokoué. Organochlorine pesticides are used in agriculture and to repel tsetse flies, malaria mosquitoes and other diseases raised. Sediment, fish, shrimp and oyster species were collected in Lake Nokoué and Cotonou Lagoon for pesticide residues analysis. The main pesticides identified in sediment were pp'-DDT and its metabolites pp-DDE and pp'-DDD, with residue levels between the detection limit and 24.4 μg/kg dry weight. Fish species commonly consumed such as Elops lacerta, Podamasys jubelini, Gobbienellus occidentalis, Ethmalosa fimbriata, Mugil cephalus and Hemichromis fasciatus were contaminated with residues of seven to nine pesticides, including pp-DDE, op'-DDD, pp'-DDD, op'-DDT, pp'-DDT, α-endosulfan, aldrin, dieldrin and γ-hexachlorocyclohexane. The levels ranged from detection limit to 289 ng/g lipid. The same pesticides were also detected in other aquatic species, such as shrimp and oysters. A summed risk assessment, comparing pesticide intake levels through fish consumption with tolerable daily intake levels proposed by the World Health Organization, showed in all cases a low risk for human health.

To evaluate lead and cadmium contamination in Moringa oleifera leaves powders marketed in Cotonou and health risks associated with its consumption, cross-sectional and analytical study were done from October 23 th , 2012 to June 20 th , 2013. Samples of Moringa powders were purchased at different outlets (health centers, supermarkets, pharmacy, etc.). Assays were performed by atomic absorption spectrophotometry after digestion according calcination method. Pb and Cd levels were compared with Codex Alimentarius standards, using the Student t test. Daily Exposure Doses (DDE) and Hazard Quotients (HQ) specific to each contaminant were calculated using a conventional method. Results revealed that the mean concentration of lead for all samples (1.526 mg/kg) exceeded of about 5.08 times the maximum allowable limit whereas cadmium levels (0.246 mg/kg) was not statistically higher than the standard. The highest concentrations of Pb and Cd are respectively 4.263 mg/kg and 0.354 mg/kg. Children are 2.3 to 3.8 times in greater danger * Corresponding author. A. K. Aissi et al. 771than adults although all QD calculated are less than 1, reflecting that there is a low risk to consumers in general. For both metals, DJE specifically linked to the consumption of Moringa was less than 2% compared to other kinds of food intake. In conclusion, the current level of contamination (with lead and cadmium) of Moringa leaves powders marketed in Cotonou is not yet an alarming threat to consumers' health. However, care must be taken to reduce chemical pollution especially soils where these plants grow.

No abstract

To determine possible human and environmental health risks, organochlorine pesticide residues were determined in vegetables grown in floodplains along the Ouémé River near Lowé in Bénin. Testing of vegetables found 13 pesticides with ΣDDT, α-endosulfan, Σdrin, and lindane being most important. The same pesticides were also detected in plants eaten by bovine cattle, sheep, and herbivorous fish. Human pesticide intake by vegetable consumption was compared with tolerable daily intake (TDI) values reported by the World Health Organization. Pesticide intake by fish consumption was estimated from residue levels in whole fish collected from the Ouémé River in 2004 and reported earlier. Fish consumption does not pose a risk for human health, but consuming vegetables that contain pesticide residues may lead to exceedance of TDI values. Based on these findings, concerns are warranted, and more work is needed to understand the full exposure profile for the local population.