Emission of Hydrogen Sulphide (H2S) from dumpsites has become a global threat due to its impact on global climate change. This study assessed the spatial and seasonal levels of H2S emissions from 6 dumpsites (LA - LF), with portable air quality meter (AEROQUAL-Series 300). Results showed that the spatial level of H2S ranged from 1.40 ppm - 14.34 ppm. Based on seasonal variation level of H2S ranged from 1.88 ppm – 3.86 ppm (p<0.05), with higher values in wet season. Meanwhile H2S were not detected in the control station (LX). Based on model for Air Quality Index (AQI), H2S emission was predominantly rated as safe and moderate, except for the two stations in the central dumpsite (LE and LF). These results confirmed the emission of H2S from the dumpsite due to anthropogenic activities. We therefore recommend policies aimed at sequestration of H2S, by the reduce, reuse and recycle policy of waste stream.  Show less

Industrial effluents containing heavy metals may reach aquatic systems either through direct discharge or surface runoff and cause damage to aquatic organisms affecting their immune system and health. Hence the present study has been undertaken to observe the effects of hexavalent chromium on the WBCs of the fresh water fish, Labeorohita. WBCs play a major role in the immune response of the fish. For acute toxicity determination, healthy fish were subjected to static bioassays. The 24, 48, 72, and 96hr LC50 values were 50.88, 42.03, 28.09 and 10.87 ppm respectively. The fish were exposed to 0.5, 1, 1.5 and 2 ppm for 20 days. Differential count of WBCs and total WBC count were determined after every five days for twenty days. Lymphocytes exhibited a decline while the other cells and total WBC count exhibited an increase due to hexavalent chromium exposure. The results were subjected to two way analysis of variance. Show less

Background Local anesthetic neurotoxicity is a common complication in clinical anesthesia, which can cause permanent nerve damage in severe cases. The T-type calcium channel is an important channel for regulating the excitability of neurons. Normally, extracellular calcium ions enter the cell through the T-type calcium channel to change the excitability of neurons. When the intracellular calcium is overloaded, it can cause cell damage. Aims To investigated the roles of T-type calcium channel in the SH-SY5Y cells injury induced by the bupivacaine. Methods The SH-SY5Y cell culture model was used to observe the effect of T-type calcium channel blocker NNC55-0396 on the neurotoxicity of bupivacaine hydrochloride by MTT methold,flow cytometry, Western blotting and other methods. Results The results show that NNC55-0396 can block the T-type calcium channel of SH-SY5Y cells, improve the decrease of cell viability caused by bupivacaine hydrochloride, reduce the level of intracellular calcium ion, reduce the expression of Cleavedcaspase-3, and reduce cell apoptosis. Conclusion The above results indicate that the T-type calcium channel is involved in the SH-SY5Y cell damage caused by bupivacaine hydrochloride, and blocking the T-type calcium channel can reduce the neurotoxicity of bupivacaine hydrochloride. Show less

Microcystins (MCs) are toxins profusely synthesized by cyanobacteria, causing livestock poisonings and endangering human health. We design and execute an experiment to investigate the attenuation (degradation) of microcystins by exposing them to gamma radiation and electron beams at doses of 0 (control), 3, 5, 10 and 15 kGy. The experimental conditions simulate microcystin contamination of aquatic environments; we thus consider (1) microcystins inside whole cells and extracellular dissolved in water, simulated by non-sonicated and sonicated cells, respectively, and (2) two acute microcystin concentrations within water. Toxicity tests of Microcystis aeruginosa detected immobilization (i.e., paralysis) of Ceriodaphniasilvestrii exposed to aqueous crude extracts of irradiated and non-irradiated M. aeruginosa (NPLJ-4 strain) at concentrations of 45 and 90 mg.L-1 (mg dry weight of freeze-dried material), and the results were analyzed using the Trimmed Spearman-Karber statistical program to obtain 48-h EC50, the average effective concentration causing immobility in 50% of organisms after 48 hours. We conclude that electron beams are effective physical agents for toxin attenuation (degradation) and reach 100% effectiveness at 5 kGy and above; their efficiency is two orders of magnitude greater than that of gamma radiation. This new body of information contributes to (1) remediating environmental water sources; (2) designing water/wastewater treatment facilities; (3) combatting chronic microcystin environmental contamination; and (4) inspiring further studies to promote the use of biomonitors (e.g., Cladocerans) to detect and evaluate microalgae contamination. Show less