Heavy Metal Levels in Pine (Pinus caribeae Morelet L) Tree Barks as Biomonitors of Atmospheric Pollution in Calabar Municipality, South Eastern Nigeria

Abstract

Biomonitoring of the air quality in Calabar was carried out by analyzing barks from pine trees (Pinus caribeae Morelet). Barks were collected from trees along highways with heavy traffic; residential areas with low traffic and the control (Cross River University of Technology, Staff Residential Area, Calabar); and analysed using atomic absorption spectrophotometer for lead (Pb) and manganese (Mn). The result showed the highest Pb level in the heavy traffic site U. J. Esuene Stadium by Calabar Road, 0.66± 0.02 mg/kg and lowest 0.01mg/kg in the control. Manganese was highest in the heavy traffic site, U. J. Esuene Stadium by Calabar Road 0.57± 0.02 mg/kg and lowest at the control 0.05± 0.01.mg/kg. The apparently low level of lead obtained in this study, compared to values that have been obtained in some other countries might be due to the unleaded petrol imported into this country. However the level of manganese might be due to its inclusion in petrol to improve its antiknock properties.

Keywords: Biomonitoring, Emission, Toxicity, Contamination, Pine bark