Heavy Metal Contamination of Vegetation by Sawmill Activities along Udu River

Abstract

Water bodies are acknowledged dumping ground for both industrial, manufacturing and domestic activities along coastlines. The Owhase creek, a typical example of a stream receiving wood wastes from sawmill industries is a source of water and livelihood to indigenous community and also as a routes to neighbouring communities. Hence, this study is carried out to review the “Heavy Metal Contamination of Vegetation by Sawmill Activities along Udu River”. While fish sampling was carried out twice, one during the wet season (July) and another one during the dry season (December), both samples were tested for heavy metal contamination using the APHA 3111A test method exploring the single acid wet oxidation method to extract the heavy metals. Results from this study revealed that sawmill activities has significant environmental impact on the Owhase creeks and its environment. The values for heavy metals investigated in this study such as Iron (Fe) and Cadmium (Cd) values ranging from 1.921 to 12.412 mg/l and 0.044 to 0.147 mg/l respectively and they are above the national regulatory limits of <1 mg/l and 0.005 mg/l respectively (NSDWQ, 2015). Also, Iron (Fe) values across kolokolo (Synodontis rukwaensis) and bounds (Cirrhinus reba) internal organs were higher than the permissible limits. Zinc (Zn) values was higher than the permissible limits in the intestine of the Kolokolo (Synodontis rukwaensis) and the gills and intestines of the bounds (Cirrhinus reba). Cadmium (Cd) values were higher than the permissible limits in the gills, intestines, and bones of the bounds (Cirrhinus reba) fish species only. It was recommended that sawdust from sawmill should not be dumped into the waterways to avoid further pollution of the waters. The level of heavy metal contamination in the water body should be monitored regularly. Such data should be used for the assessment of health risk in the habitat.