concentrations of eight metals namely, cr, mn, fe, co, ni, cu, zn and pb were examined in the surface sediments of discharge channels of six industries in lagos using x-ray fluorescence spectrometry.these channels drain into the isolo canal which empties into the lagos lagoon and eventually into the atlantic ocean. this study was conducted to detect any contamination levels within the sediment...

Nanotechnology is an area of intense commercial development, and concerns have been raised about the possible impacts to the environment. Zinc oxide nanoparticles (nanoZnO) are used in transparent sunscreens and may find their way into the environment through wastewater treatment plants and through skin contact with water. The purpose of this study was to examine the bioavailability of Zn in fa...

The objective of the present study was to investigate the influence of chronic exposure to municipal sewage treatment effluent at environmentally relevant concentrations on immune parameters in rainbow trout (Oncorhynchus mykiss), including the assessment of potential differences in reactivity between sexually mature male and female fish. Trout were exposed to 1.5 and 15% (v/v) secondary treate...

The effluent from anaerobic digestion process has high concentrations of nutrients, particularly nitrogen, essential for plant growth but is not suitable for direct disposal or application due to high chemical oxygen demand (COD), low dissolved oxygen (DO), odour issues and is potentially phytotoxic. This research explored the optimum conditions of anaerobic effluent for application and dilutio...

A laboratory study was carried out to determine the effect of bark boiler ash on AOX concentration in bleach plant effluent. The removal of A O X was found not to be significant at typical daily discharge rates of boiler ash. To remove significant amounts of AOX, extremely large quantities of ash were required. When incremental quantities of ash were added to the bleach plant effluent, an incre...

The physicochemical qualities of a refinery effluent and water and sediment of an effluent receiving water body were investigated. The treated refinery effluent contained very high concentrations of phenol (11.06 mg/l), oil and grease (7.52 mg/l), ammonia (8.52 mg/l), COD (91.76 mg/l), TDS (390.6 mg/l) and phosphate (6.2 mg/l), but low in sulphide, nickel, lead, copper and chromium, which were ...

Industrial effluents, controversially, is one of the largest and major contributors of pollution in aquatic ecosystem and affects the aquatic organisms in general and fishes in particular. Several laboratory studies were conducted to evaluate the effects of both treated and untreated effluents on fish. The studies showed wide ranges of toxicity at organismal as well as at population levels. The...

The impact of industrial effluent on the Oruku River in southwestern region of Nigeria was investigated. Surface water, sediment, ground water and industrial effluent samples were obtained bimonthly for 18 months (March 2005 to September 2006). Effluent characteristics varied widely with averages of DO (4.25±1.3 mg/L), BOD (27.5±43 mg/L), Pb (0.41±0.26 mg/L), Cr (0.26±0.48 mg/L) and Ni (0.19±0....

Bacillus pumilus and Paenibacillus sp. were applied on the paper mill effluent to investigate the colour remotion. Inocula were individually applied in effluent at pH 7.0, 9.0 and 11.0. The real colour and COD remotion after 48h at pH 9.0 were, respectively, 41.87% and 22.08% for B. pumilus treatment and 42.30% and 22.89% for Paenibacillus sp. Gel permeation chromatography was used to verify th...

Laboratory single-species toxicity tests are used to assess the effects of contaminants on aquatic biota. Questions remain as to how accurately these toxicity tests predict site-specific bioavailability and chronic effects of metals, particularly in streams that are effluent-dominated or dependent on effluent discharge for flow. Concurrent 42-d Hyalella azteca exposures were performed with cadm...