Bioaccumulation of heavy metals, lipid profiles, and antioxidant status of snails (Achatina achatina) around cement factory vicinities.

Some snails (Achatina spp) can be used as a biosensor of heavy metal poisoning. This study thus estimated some heavy metal levels, antioxidant markers, and lipid profiles of snails handpicked around cement factory vicinities in Ogun State, Nigeria. Snails and soil samples were collected from Oke, Ewekoro, Papalanto, and Mowodani Imeko-Afon (control site). Lead (Pb), cadmium (Cd), and arsenic (As) levels were estimated in the soil, snail foot, hemolymph, and shell using Atomic Absorption Spectrophotometry. Triacylglycerol (TAG), phospholipids (PHOL), cholesterol (CHOL), malondialdehyde (MDA), and reduced glutathione (GSH) levels, as well as glutathione-S-transferase (GST), lactate dehydrogenase (LDH), and arylesterase (AR) activities in the hemolymph, were estimated spectrophotometrically. The snails collected from the Oke site had the highest foot Pb (274.66 ± 13.50 mg/g tissue), CHOL, TAG, PHOL levels, and GST activity when compared with other sites. Snails collected from Papa had the highest Cd levels (1.79 ± 0.74 mg/kg), As (1206 ± 18.87 mg/g tissue) in the foot, and LDH activity, while Ewekoro snails had highest MDA levels and AR activities but the lowest GSH levels. Additionally, there were negative correlations between the heavy metal levels and the activities of GST and AR as well as GSH levels, while positively correlating with LDH activity and MDA level. Workers and the general public around cement factories are at a greater risk of heavy metal-induced pathologies. More so, consumption of snails around these sites may be deleterious to health.

Occurrence, removal and health risk assessment of phthalate esters in the process streams of two different wastewater treatment plants in Lagos and Ogun States, Nigeria.

Phthalate esters (PEs) are one of the environmentally active organic pollutants capable of causing endocrine disruption. The levels of PE congeners were determined in the influent and effluent from Covenant Oxidation Pond (COP) and Ikeja Wastewater Treatment Plant (IWWTP). Standard methods were adopted for determining the physical and chemical parameters of the water samples. The water samples for PE congener's determination were collected, acidified and stored at 4 °C prior to liquid-liquid extraction and analysis by gas chromatograph. The possible health risk associated with the usage of effluent-polluted river water was also investigated. The pH and temperature ranges were within the Federal Ministry of Environment (FME) 2001 guideline limits while the dissolved oxygen, biochemical oxygen demand and chemical oxygen demand were above the limits. The IWWTP performed better at removing PEs at 54% compared to 43.3% on average at COP. The health risk of individual PE congener showed no non-cancer effects (HQ) as the values varied from 5.01E-05 (DAP) to 1.52E-02 (DEHP) for adults and 1.17E-04 (DAP) to 3.76E-03 (DBP) for children at COP, while at IWWTP, it ranged from 8.06E-05 (DIBP) to 1.09E-02 (DEHP) for adults and 5.68E-04 (MMP) to 2.54E-02 (DEHP) for children. Notwithstanding, the usage of effluent-polluted river water by local communities downstream may result in carcinogenic effects due to the cumulative effects of the PE congeners as the values obtained for adults and children for the ingestion and dermal routes for the two waste process streams ranged from 4.67E-06 (IWWTP) to 6.22E-05 (IWWTP) and 2.18E-05 (IWWTP) to 7.18E-05 (COP), respectively.

Ionoregulatory Disruption and Acetylcholinesterase Activity in Aluminium Toxicity: Effects of Vitamins C and E.

To investigate the effects of vitamin C and E on electrolyte profile and the activity of acetylcholinesterase (AChE) in Aluminium (Al) chloride exposed rats, thirty-six male rats were used for this study. The animals were randomly grouped into six (n=6); group I (Control) was given normal saline. Group II (Al only) was exposed to 20mg/kg body weight (BW) of Al. Groups III (Vitamin C only) and IV (Vitamin E only) were administered 200mg/kg BW of vitamin C and vitamin E respectively. Groups V (Al + Vit C) and VI (Al + Vit E) were exposed to 20mg/kg Al and were treated with 200mg/kg vitamin C and vitamin E respectively. Al exposure resulted in a significant (P<0.05) increase in plasma calcium and erythrocyte magnesium concentrations compared with control. The erythrocyte sodium concentration of group treated with Al alone was significantly (P<0.05) higher by 2.01folds than the control group. While the two vitamins were unable to correct the disruption in calcium homeostasis, they ameliorated the intracellular levels of sodium and magnesium ions. A reduction in the activity of AChE (1378.90±130.02U/L)was observed in erythrocyte of the group exposed to Al when compared to the control (1968.80±283.72U/L). Treatment with vitamins C and E further inhibited erythrocyte AChE activity by 34% and 39% respectively compared to a 30% inhibition by Al only. Positive associations were observed between erythrocyte magnesium and blood sodium, and plasma calcium and erythrocyte sodium levels. Negative associations were however observed between plasma AChE activity and erythrocyte sodium and magnesium levels. In conclusion, vitamins C and E ameliorated ionoregulatory disruptions caused by sub-acute aluminium on only erythrocyte sodium and magnesium levels but not on plasma calcium level and erythrocyte acetylcholinesterase activity.

Heavy metal burdens of public primary school children related to playground soils and classroom dusts in Ibadan North-West local government area, Nigeria.

Information about heavy metal burden of children in Nigeria related to playground soils and classroom dusts is lacking. Playground soil, classroom dust, blood and spot urine samples (n=253) were collected from 6 urban and 2 semi-rural public schools in Ibadan North-West, Nigeria. Samples were analysed for Pb, Cu, Zn, Fe and Mn. Mean blood Pb levels in urban area (male, 41.66±8.78µg/dl vs. female, 40.64±5.46µg/dl) were twice as high as those in semi-rural area (male, 19.71±3.73µg/dl vs. female, 20.65±2.26µg/dl). Concentrations of Pb, Cu, Zn, and Fe in soil and dust samples in the urban schools were between 2- to 4-fold greater than that of semi-rural schools. No correlation was observed between blood and dust metals. A positive correlation (r=0.168, p=0.008) was observed between blood Pb and playground soil Pb. Pb burden in the children might be from their schools' playgrounds and other yet unidentified sources.