Polyaromatic Hydrocarbons (PAHs) and Inorganic Chemical Contaminants at Refuse Dumpsites in Awka, South Eastern Nigeria: A Public Health Implication
J. K. Nduka *
Environmental Chemistry Toxicology Research Unit, Pure and Industrial Chemistry Department, Nnamdi Azikiwe University, P.M.B. 5025, Awka, Anambra State, Nigeria.
C. Anyakora
Department of Pharmaceutical Chemistry, University of Lagos, Nigeria.
E. Obi
Department of Pharmacology, College of Health Sciences, Nnamdi Azikiwe University Teaching Hospital, Nnewi Campus, Nnewi, Nigeria.
F. O. Obumselu
Environmental Chemistry Toxicology Research Unit, Pure and Industrial Chemistry Department, Nnamdi Azikiwe University, P.M.B. 5025, Awka, Anambra State, Nigeria.
T. E. Ezenwa
Department of Chemistry, Anambra State University, Uli, Anambra State, Nigeria.
L. C. Ngozi-Olehi
Department of Chemistry, Alvan Ikoku Federal College of Education, Owerri, Imo State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aim: Is to determine the levels some PAHs and inorganic contaminants in refuse dump soil samples within residential areas in Awka in Anambra State, Nigeria.
Study Design: Ten soil samples (five study samples and five control samples) taken from five major refuse dumpsites in Awka, South Eastern Nigeria were analyzed for the presence of 16 polynuclear aromatic hydrocarbons (PAHs) (organic contaminant) and inorganic contaminants using their respective standard methods.
Place and Duration of Study: Soil samples were collected from Awka in Anambra State while the analysis was carried out at the Department of Pharmaceutical Chemistry, University of Lagos Nigeria between November 2010 and January 2011.
Methodology: Gas chromatography/mass spectrometry was used for the analysis of 16 specific target compounds which included naphthalene, acenaphthylene, acenaphthene, flourene, phenanthrene, anthracene, flouranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]flouranthene, benzo[k]flouranthene, benzo[a]pyrene, benzo[ghi]perylene,dibenz[a, h]anthracene and indeno[1,2,3-cd]pyrene. Four isotopically labelled polynuclear aromatic hydrocarbons (acenaphthene-d10, phennanthrene-d10, chrysene-d12 and perylene-d12) were used for internal standardization. Inorganic contaminants were analyzed using their respective standard methods, these include nitrate, nitrites, chloride, hardness, TDS in addition to heavy metals, cation exchange capacity (CEC) etc reported in our previous study.
Results: All 16 PAHs were found in most of the samples and their controls, with highest concentration in sites A, B and C. The range of PAHs in the sites where as follows; site A (14.20 – 710.02mg/kg), site B (Nd-2392.06mg/kg), site C (Nd – 1158.22mg/kg), site D (Nd – 0.92mg/kg) and site E (Nd – 0.84mg/kg). Nitrates were as follows: site A (52.43mg/kg), site B(50.30mg/kg), site C(62.45mg/kg),site D(45.20mg/kg) and site E(38.50mg/kg). These and other examined parameters were present in an amount that can constitute environmental and public health problem.
Conclusion: It is concluded that indiscriminate dumping of refuse within residential areas can accentuate the environmental and public health- problem of the inhabitants.
Keywords: PAH, inorganic contaminant, refuse dumpsite, environmental pollution, public health, South Eastern Nigeria