The concentration of some heavy metals in the effluents of five (5) companies operating in Enugu State, Nigeria were determined using atomic absorption spectrophotometer. The heavy metals detected in this study include Arsenic (AS), Cadmium (Cd), Chromium (Cr), Iron (Fe), Mercury (Hg), Manganese (Mn), Nickel (Ni), Lead (Pb) and Zinc (Zn). Most of the samples were found to contain the metals in various concentrations. Most of concentration were above the W.H.O maximum recommended contaminant concentration level. The highest average concentration of heavy metal was detected in Lead with a concentration of 2.685mg/L. The highest average concentration were found to be 0.253mg/L for Arsenic, 0.105mg/L for Cadmium, 0.122mg/L for Chromium, 2.120mg/L for Iron, 0.050mg/L for mercury, 1.522Mg/L for Manganese, 0.546mg/L for Nickel and 0.885mg/L for Zinc. This study reveals the need for enforcing adequate effluent treatment method before their discharge to surface water or environment to reduce their potential environmental hazards.

TABLE OF CONTENTS

Title page i

Letter of approval ii

Certification/Approval Page iii

Approval page iv

Dedication v

Acknowledgement vi

Abstract v

Table of contents vi

CHAPTER 1

1.0 INTRODUCTION 1

1.1 Background of the Study 1

1.2 Statement of the Problem 2

1.3 Objectives of the Study 5

1.4 Scope and Limitation of the Study 3

1.4.1 Limitation 4

1.5 Method of Research 4

1.6 Significance of the Study 5

CHAPTER TWO

2.0 LITERATURE REVIEW 6

2.1 Heavy Metal 6

2.2 Harmful Effects to Humans and the Environment 11

2.2.1 Lead 11

2.2.2 Humans 12

2.2.3 Environment 16

2.3 Mercury 23

2.3.1 Humans 24

2.3.2 Environment 29

2.4 Cadmium 33

2.4.1 Humans 34

2.4.2 Environment 37

2.5 Chromium 43

2.5.1 Humans 44

2.5.2 Environment 47

CHAPTER THREE

3.0 METHODOLOGY 51

3.1 Instrumentation 51

3.2 Sampling 51

3.3 Sample Preparation 52

3.4 Procedure 53

CHAPTER FOUR

4.0 Results And Analysis 54

CHAPTER FIVE

5.0 Discussion 63

5.1 Conclusion 66

5.2 Recommendation 67

References 68

CHAPTER 1

6.0 INTRODUCTION

6.1 Background of the Study

Heavy metal is a member of a loosely defined sub-set of elements that exhibit metallic properties. This includes the transition metals metalloids, lanthanides and actinides (IUPAC).

Pharmaceutical effluents are waste generated by pharmaceutical industries during the process of drugs manufacturing. The increase in demand for pharmaceuticals has resulted in a consequent increase in pharmaceutical manufacturing companies in the country and hence increased pharmaceutical waste which most times contain substantial amount of heavy metals.

Heavy metals such as lead, mercury, cadmium Nickel, chromium and other toxic organic chemicals or phenolic compounds discharged from pharmaceutical industries are known to affect the surface and ground water (Foess and Ericson, 1980). These effluents are usually discharged into the environment and when improperly handled and disposed, they affect both human health and the environment (Osaigbovo and Orhue, 2006, Ayodele et al, 1996, Anetor et al., 1999).

Studies showed that for the last 40 years, various devastating ecological effects and human disasters have arisen majorly from industrial wastes containing heavy metals causing environmental degradation (Abdel-Shafy and Abdel-Basir, 1991 Sridhar et al 2000). Following the increasing use of pharmaceuticals products in recent years, this having caused the industry to become one of the major contributors to industrial waste containing heavy metal in the environment. It is on this background that the project is investigating to determine presence of heavy metals from pharmaceutical effluent

1.2 statement of the problem

Various devastating ecological effects and human disasters have arisen majorly from industrial wastes containing heavy metals causing environmental degradation (Abdel-Shafy and Abdel-Basir, 1991 Sridhar et al 2000).

Following the increasing use of pharmaceuticals products in recent years, this having caused the industry to become one of the major contributors to industrial waste containing heavy metal in the environment.

1.3 OBJECTIVE OF THE STUDY

The objective of this project is to determine the content and concentrations of heavy metals in effluents from some selected pharmaceutical companies in Enugu.

1.4 Scope /Delimitation of the Study

This project focused on the identification of heavy metals and their concentrations in effluent from some selected pharmaceutical companies in Enugu with a view to determining the rate of introduction of such metals into the environment.

It does not cover the treatment or purification of such effluent.

1.4.1 Limitation

The limitation of this project work include the challenges encountered in collecting effluent samples from pharmaceutical companies.

Financial constrain also pose some difficulties to the success of this project work.

1.5 Method of Research

The method of research adopted include the following:

v The use of World Wild Web (internet)

v Pharmaceutical handbook was used in writing the literature

v Samples were collected form pharmaceutical companies at their point of discharge.

v The collected samples were analyzed in the laboratory by the use of Atomic Absorption spectrophotometer (AAS) to identify the metals and obtain their concentrations in every sample.