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ABSTRACT
The goal of this study was to integrate the activities of paint deterioration of microbial communities (microcosms) on the basis of environmental factors. The effect of temperature and pH on bacterial degradation of latex paint under humid condition by bacterial isolates was studied. Results obtained revealed that paint industrial waste (PIW) and paint film scrap (PFS) contained approximately 28.2% to 37.3% of dry organic content (DOC), pH 6.6 to 8.3, optical density (OD) 2.5 to 3.9 and undetermined amount of Ca^sup 2+^, Na^sup +^, K^sup +^, SO^sub 4^^sup 2-^ and NO^sub 3^^sup -^. Thirteen (13) isolates were obtained from PIW and fifty two (52) from PFS. The main heterotrophic count ranged from 8.7 to 9.4 × 10^sup 8^ cfuml^sup -1^ for PIW and 3.4 to 6.8 × 10^sup 6^ cfuml^sup -1^ for PFS. The bacterial genera and their percentage occurance for PIW and PFS were: Pseudomonas (40:32%), Bacillus (26:44%), Norcadia (9:6%), Streptomyces (0:6%), Alcaligenes (11:3%), Micrococcus (14:7%) and Flavobacterium (0:27%) respectively. The organisms exhibited various degree of paint degradation under different temperature and pH points. Pseudomonas demonstrated the highest rate of degradation at pH 7.4 and the lowest at pH 4.2. Bacillus had its highest rate at pH 6.3 and lowest at pH 3.5 while that of Micrococcus occurred at pH 4.2 and 8.1 respectively. Equally, Pseudomonas and Bacillus had double peaks of degradation at 28oc and 40oc while that of Micrococcus occurred only at 40oc. However, 28oc and 40oc are considered optimal and maximal temperature for biodegradation of paint. Also, the effect of pH and temperature was independent and insignificance at P < 0.05. The study therefore, indicated that paint and painted surfaces (objects) can be preserved from bacterial contamination, deterioration and degradation by controlling the storing pH and temperature.
KEYWORDS: Paint, temperature, pH, biodegradation, significance.
INTRODUCTION
Paint is described as a liquefiable mastic material capable of being applied in a thin layer over a surface. On application, the thin layer is converted into an opaque solid film (Kappock,1977; Linder,2005). Paint is made of two distinct phases; the liquid phase which is mainly oil and a powdered solid phase which gives colour and body to the mixture. Paint therefore is used either for protection to prevent environmental weathering or for decorative and...