Breakfast networking meeting for International Year of Chemistry – University of Cambridge Scientists sharing a chemical moment in

time with scientists in West Africa

Date: 18th January 2011, Time: 8 – 10: 00 am

Venue: Rivers State College of Science and Technology, Port Harcourt, Nigeria and Department of Biochemistry, University of Cambridge

Mrs Comfort Uchendu, Chief Lecturer, Rivers State College of Science and Technology, BSc, MSc

Paper Presentation By

MRS COMFORT UCHENDU CHIEF LECTURER, RIVERS STATE COLLEGE OF SCIENCE AND

TECHNOLOGY,

BSC, BOTANY UNIVERSITY OF NIGERIA NSUKKA.

MSC, ENVIRONMENTAL BIOLOGY, UNIVERSITY OF SCIENCE AND TECHNOLOGY, PORT HARCOURT.

MA, PUBLIC ADMINISTRTION, AMBROSE ALLI UNIVERSITY, EKPOMA

THE IMPACT OF ORGANIC WASTE DISPOSAL ON THE WATER

QUALITY IN THE NEW CALABAR RIVER, NIGER DELTA, NIGERIA.

A study of the physico-chemical parameters of’ tile New Calabar River was carried out from January to June, 2007.

The parameters studied were temperature, Ph, turbidity, salinity, primary nutrients (nitrates and phosphates), DO, BOD, TDS, conductivity, redox potential, and heavy metals (zinc, lead, copper and cadmium).

INTRODUCTION

Five sampling stations were considered. Samples were collected with appropriate containers for water quality analysis. Water temperature varied slightly ranging from 24.5 to 31.1 degrees Celsius. The pH was relatively constant ranging between 6.47 and 7.29.

The trip provided an overview of the study area which enabled the establishment of points of activities along the river banks (stations one, two, three, four and five). Station one was a solid waste dump site in the river where a jetty was also located. Station two was occupied by Modant Engineering Limited and Pivot Nigeria Limited while station three was occupied Delta Marine Company. Stations four and five were river banks distant from these industrial sites and therefore served as control stations.

RESULTS

The following physico-chemical parameters showed significant differences both in time and space: Nitrate BOD Conductivity Total dissolved solids (TDS), The highest DO value

(8.00mg/L) was obtained at station five (control station) while the lowest (2.00mg/L) was recorded at station one which was a waste dump site.

Turbidity, salinity, redox potential, and phosphate showed no significant differences both in time and space. Copper showed significant difference in time.

RESULTS

Surface Water Temperature: The measurement of surface temperature was done in-situ in the field, using mercury in glass thermometer. The bulb of the thermometer was fully immersed in the water at each sampling station and held still until a constant reading was established. The value was noted and recorded in degrees Celsius.

  pH: pH in water was determined in the laboratory using a Membrane pH meter. The

sample was shaken thoroughly to provide homogeneity and the pH electrode was standardize in a standard buffer solution and then immersed in the sample and the result was read off from the pH meter (Model H 18314 membrane, HANNA instruments).

  Conductivity: The conductivity of the respective water samples was determined using a

conductivity meter. Samples were measured by putting a small quantity of the water sample into a cup-like probe attached to the water with the pointer pressed down. The knob was adjusted until it stabilized and the reading was recorded in µs/cm.

  Turbidity: The turbidity of the water samples was measured using an electrical device

(Water Checker Model U-10 micron HORIBA). A small quantity of the water sample was poured in a container, attached to the meter and the probe immersed into the water. The meter was allowed to stabilize before recording the readings in NTU.

 

METHODOLOGY

Dissolved Oxygen (DO) (Using Winkler’s Modification Method) and Biological Oxygen Demand (Bods): The methods used are as described in standard method for water and wastewater analysis (APHA, 1975, Section 422). The results were expressed in mg/L.

Salinity: The salinity of the collected samples was determined following Argentomertic method as described in the Standard Methods for Water and Wastewater Analysis (APHA, 1975, Section 408). The salinity was measured in practical salinity unit (psu).

  Nitrate in Water (Brucine Method): Nitrate (NO3) level in the water samples was

determined following the procedure described in the Standard Methods for Water and Wastewater Analysis (APHA, 1975, Section 419). The concentration of Nitrate (NO3) was calculated in mg/L.

Phosphate in Water (Ascorbic Acid Method): Phosphate in water was determined by Ascorbic Acid method as described in APHA (1975) section 425. The concentration of phosphorus was recorded in mg/L by referring the absorbance values to a standard reference curve.

Heavy Metals Analysis: The concentration of each heavy metal in water and sediment was determined from the samples after the calibration runs using appropriate salts of the metals to investigate Cadmium (Cd), Lead (Pb), Zinc (Zn), and Copper (Cu). Atomic Absorption Spectrophotometer (AAS, model 2380) was used to determine the values (precision + 0.01%).

METHODOLOGY

Recommendations

1) The waste dump at station one should be removed and another waste dump site provided for the people living along the New Calabar River water front (lwofe) where the wastes can be separated and recycled or incinerated.

2) The results of this study be used as a baseline study for comparison with other waters in the Niger Delta region which are already affected by human and industrial activities.

3) The Federal environmental regulatory body should evaluate existing sources of coastal pollutants as well as to develop marine monitoring programmes designed to generate information useful in making management decisions to protect the coastal environment of the Niger Delta.