Health Implications of Occupational Exposure of Butchers to Emissions from Burning Tyres.

BACKGROUND: Flames from burning scrap tyres are used in de-furring animals for human consumption in most parts of Nigeria. Emissions from tyres are known to contain a myriad of toxic mixtures especially particulate matter (PM), volatile organic compounds, hazardous air pollutants, and inspirable metals, some of which are known human carcinogens. This cross-sectional study investigated the deleterious health effects of these emissions in occupationally-exposed workers at the Dei-Dei Abattoir, Abuja, Nigeria. METHODS: A total of 156 respondents were divided into two groups. Group 1 (124 butchers) and group 2 [32 administrative staff (AS)]. Data from digital spirometry were used to determine the association between chronic exposure to tyre emissions and lung function. Urinary 1-Hydroxypyrene concentration, phenolic compounds levels and heavy metal concentrations were determined. Also ambient PM and polycyclic aromatic hydrocarbons (PAHs) concentrations at 3 delineated points in the abattoir were measured. FINDINGS: Spirometry results showed significant deterioration of lung function in the butchers. The concentration of 1-Hydroxypyrene (µg/molCret) in the post-shift urine samples of the butchers was significantly higher (P < 0.05) in butchers relative to the AS (0.52 ± 0.13 Vs 0.20 ± 0.07, respectively). Similarly the concentrations of zinc and nickel (mg/l) were significantly higher in the butchers compared to the AS (zinc: 0.91 ± 0.19 Vs 0.31 ± 0.28, respectively; nickel: 0.11 ± 0.06 Vs 0.06 ± 0.02, respectively). Anthracene, fluoranthene, pyrene, benzo-a- pyrene, and PM concentrations were significantly higher at the de-furring point when compared to the wash bay and the administrative building, especially between 8.00 and 8.30 am. CONCLUSION: Occupational exposure to scrap tyre emissions resulted in significant adverse health effects. The existing laws banning the use of burning tyres in meat processing should be enforced while the use of personal protective equipment should be encouraged in abattoirs.

Biotechnological tools for environmental sustainability: prospects and challenges for environments in Nigeria-a standard review.

The environment is a very important component necessary for the existence of both man and other biotic organisms. The degree of sustainability of the physical environment is an index of the survival and well-being of the entire components in it. Additionally, it is not sufficient to try disposing toxic/deleterious substances with any known method. The best method of sustaining the environment is such that returns back all the components (wastes) in a recyclable way so that the waste becomes useful and helps the biotic and abiotic relationship to maintain an aesthetic and healthy equilibrium that characterizes an ideal environment. In this study, the method investigated includes biological method of environmental sustainability which seeks to investigate the various biotechnological tools (biotools) in current use and those undergoing investigations for future use.

Environmental pollution levels of lead and zinc in Ishiagu and Uburu communities of Ebonyi State, Nigeria.

Water and soil samples from the area were therefore analyzed for their lead and zinc content. Computation of pollution statuses of lead and zinc revealed topsoil lead geoaccumulation indices of -0.143 and -0.069 and zinc geoaccumulation indices of 1.168 and 0.713 for Ishiagu and Uburu respectively. The pollution indices were determined to be 0.499 and 0.3564 for soil in Ishiagu and Uburu respectively and also 5.11 and 2.42 for water in Ishiagu and Uburu communities respectively. Water/soil concentration ratio were found to be 0.0018 and 0.0014 for lead in Ishiagu and Uburu respectively. On the other hand, the water/soil concentration ratio for zinc was computed to be 0.001 and 0.0008 for Ishiagu and Uburu respectively. These results seem to suggest that the pollution of the environment by these heavy metals in the areas were as a result of the water being contaminated by lead and zinc not necessarily their concentrations in the soil.

Quantitative modelling of crude oil toxicity using the approach of cybernetics and structured mechanisms of microbial processes.

Cybernetics and structured approach to biochemical processes in microbial cells offer the status of using various cell components of Azotobacter as molecular markers in toxicity assay of environmental toxicants. The intra-linked dynamic physicochemical reactions of the basic macromolecules--DNA, protein and membrane lipids--with respect to the crude oil in the growth environment, results in an 'impulse transfer function'. The structured effects are reduction in both DNA and protein levels, and an elevated level of lipid peroxidation products. Toxicity index (Ti) of the crude oil, at a given concentration, is the percent ratio of the summation of the products of these effect parameters' and their respective weightings, relative to control. The EC50 is the effective percent (w/v) concentration of the crude oil at which a toxicity index of 50% was recorded, and this corresponded with about 44% loss in nitrogen fixation of the diazotrophic bacterium.