International Research Symposium on Pure and Applied Sciences (IRSPAS)
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Item Monitoring heavy metal air pollution using moss as a biomonitor and developing a mathematical relationship based on surrogate approach, to determine heavy metal loads in moss(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Yohani, A. A. R .; Deeyamulla, M. P.Atmospheric pollution is one of the major problems that mankind is dealing with. Under air pollutants, heavy metals are toxic and persist in the environment. Monitoring heavy metal loads in the atmosphere is therefore of immense importance for environmental studies. As direct monitoring instruments are expensive and difficult to handle in extreme conditions, the biomonitors can be used as an alternative, cost effective method to monitor heavy metal air pollution. In this study, Barbula unguiculata moss species was used as the biomonitor to determine atmospheric heavy metal content since it was readily available in all selected areas. Sampling areas were divided into 4 major categories i.e. Pettah and Borella under the heavy traffic areas, University of Kelaniya under the moderate traffic area, Kegalle (Nelumdeniya) under the less traffic area and Sapugaskanda as the model area for industrial pollution where number of major industries are present. In each study area, five sub sampling sites were chosen and those selected sites were triplicated. Five heavy metals (Cu, Cr, Zn, Pb and Ni) were analyzed using Flame Atomic Absorption Spectrophotometry. Sinharaja rainforest was treated as the background area where anthropogenic activities and industrial emissions were minimum. According to the native moss analysis, two heavy traffic areas, industrial area and moderate traffic area were in contaminated levels with all five selected heavy metals. Based on the calculated pollution load index values, atmospheric heavy metal pollution in selected areas follows the order, Pettah > Borella ~ Sapugaskanda > University of Kelaniya > Kegalle. Besides the atmospheric heavy metal loads, same heavy metal loads in soil samples from the same five areas were analyzed. The correlation analysis was performed and there was no any clear correlation among heavy metal loads in the atmosphere and the soil of the selected five areas as the soil heavy metal loads depend on several other external factors. It was found from the study that surrogate approach was an effective methodology for the determination of heavy metal contents by using only two surrogate heavy metals per each site. By using Pearson Correlation Analysis and Multiple Linear Regression Analysis, mathematical relationships were developed to estimate heavy metal loads and those were validated and the reliability was assessed.Item Comparison of the tolerance of cadmium (Cd2+), lead (Pb2+) and their mixtures by Staphylococcus sp. isolated from a water body receiving textile effluent(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Aththanayake, A. M. K. C. B.; Rathnayake, I. V. N.; Deeyamulla, M. P.Cd2+ and Pb2+ are widely used heavy metals in industries such as electroplating, battery, plastic and pigment production etc. These heavy metals are considered as highly threatening substances to human body, which can cause carcinogenic effects and organ dysfunctions. The isolated Staphylococcus sp. from waste effluent was exposed to a range of single and mixed metal concentrations of Cd2+ and Pb2+ in modified Tris-minimal medium. The growth patterns of Staphylococcus sp. during 24-hour intervals were monitored spectrophotometrically at 600 nm. The effective concentrations (EC50) of Staphylococcus sp. were calculated up to 72 hours. Staphylococcus sp. showed a gradually increasing growth in Pb2+ containing medium, where as a decreasing growth in Cd2+ containing medium was observed after 48 hours. It showed an increasing growth when grown in the presence of both metals. EC50 values at 24, 48 and 72 hours with Cd2+ and their mixture showed a gradual decrease while EC50 values of Pb2+ showed a gradual increase. Results of the study indicated that Staphylococcus sp. has comparatively high tolerance to Pb2+ than Cd2+ and their mixturesItem Determination of enhancement of atmospheric heavy metal concentration and total nitrogen content in moss from traffic exposure(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Perera, L. E. H.; Deeyamulla, M. P.Heavy metal concentration and total nitrogen content were surveyed using moss as a bioindicator. The effect of NOX emissions from traffic on moss tissue nitrogen and tissue concentrations of Pb, Cu, Cd and Cr were determined. Moss species, Barbula unguiculata (70 samples) growing next to roads that were exposed to different traffic densities as high, medium and low were collected from different sites in the Western province of Sri Lanka. Selection of the sampling sites were based on google map online traffic application. Results were compared with background level concentrations of heavy metals and total nitrogen content obtained from Sinharaja rain forest where the anthropogenic influence is minimum. Bioaccumulation of heavy metals were determined by Atomic Absorption Spectrophotometer (AAS). Colorimetric method and the conventional Kjeldhal method were compared for the determination of total nitrogen content and the total nitrogen amount was determined using the rapid colorimetric method. Background levels of Pb, Cu, Cd and Cr were 7.23 ± 2.11 µg/g, 5.53 ± 1.75 µg/g, 0.17 ± 0.06 µg/g and 6.61 ± 2.58 µg/g respectively. Background sites showed a total nitrogen content of 3.25 ± 0.05 mg/g. Mosses collected from sites that were exposed to high traffic had a total nitrogen content ranging between 7.19 - 13.16 mg/g. The Pb, Cu, Cd and Cr contents had ranges between 30.87 - 45.98 µg/g, 63.73 - 95.24 µg/g, 3.22 - 3.76 µg/g and 41.98 - 64.12 µg/g respectively. Sites that were exposed to medium traffic showed a total nitrogen content ranging between 6.62 - 8.67 mg/g. The Pb, Cu, Cd and Cr contents had ranges between 21.17 - 28.39 µg/g, 44.38 - 56.09 µg/g, 1.59 - 2.94 µg/g and 24.60 - 41.41 µg/g respectively. Sites that were exposed to low traffic showed a total nitrogen content ranging between 6.84 - 10.63 mg/g. The Pb, Cu, Cd and Cr contents had ranges between 10.40 - 13.62 µg/g, 26.36 - 39.83 µg/g, 1.06 - 1.62 µg/g and 16.71 - 19.54 µg/g respectively. This work indicates that the heavy metal contents have a positive correlation with the traffic exposure with Cu being greater than other heavy metals (Pb, Cr, Cd) and that the total nitrogen content does not show a clear correlation with the traffic exposure. Therefore, in order to obtain a positive correlation, the traffic exposure should be compared with the stable isotope ratio (δ 15N).Item Atmospheric heavy metal analysis in Chronic Kidney Diseases of unknown aetiology (CKDu) affected areas using moss bio-monitoring(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) De Silva, K. M. T.; Deeyamulla, M. P.Air pollution is a common issue faced by both urban and rural areas due to many factors. Heavy metals are one of the major types of air pollutants that can cause different health issues in humans including kidney diseases. Although only a handful of studies have been conducted so far to link air pollution with kidney disease, correlations have been found between atmospheric particulate matters with kidney diseases. These particulate matter are capable of absorbing heavy metals. Cr, Pb and Cd are three such heavy metals identified with a direct link towards kidney diseases. Therefore, in this study, the atmospheric levels of these three heavy metals were investigated in areas with high occurrence of Chronic Kidney Diseases. The study was carried out using moss biomonitoring as the method of atmospheric monitoring. Two variations of this method which are native moss analysis and moss bag technique were used. In native moss technique, moss samples (Hyophila involuta) of the selected species were collected from different locations of the study area and were analysed. In the moss bag method, nylon bags containing the selected moss species were placed in different locations of the study area, keeping undisturbed for 100 days, collected and analysed. In this study Medawachchiya was selected as the study area due to the high records of CKDu in the area. Levels of Cr, Cd and Pb in 4 different geographic locations within Medawachchiya were compared and the accumulation of heavy metal during 100 day period was analysed using moss bag technique. All the analysis was done using Flame Atomic Absorption Spectrophotometry (GBC 5000). According to the native moss analysis, highest amount of heavy metal detected was Cr (22.29 ± 3.15 μg/gmoss), followed by Pb (16.48 ± 1.80 μg/gmoss) and Cd (1.21 ± 0.06 μg/gmoss). According to the Native moss analysis, the highest levels of Cr, Pb and Cd were recorded at Kirigollewa Gramaniladhari division. There were no significant difference between Cd, and Pb amounts between Kirigollewa and other areas (P=0.357), but there was a significantly higher amount of Cr in this area compared to other areas (P=0.033). Considering the CKDu patient data, Kirigollewa can be recognized as a high prevalent area of the disease. Moss bag analysis revealed an increase of Pb and Cr levels during the given period but a decrease of Cd level in all areas. However, to establish a possible correlation with CKDu, more analysis is required.Item Assessment of polycyclic aromatic hydrocarbons and heavy metals in the vicinity of an oil refinery in Sri Lanka using moss as a bioindicator.(International Research Symposium on Pure and Applied Sciences, 2017 Faculty of Science, University of Kelaniya, Sri Lanka., 2017) Nirmani, L. P. T.; Deeyamulla, M. P.Polyaromatic hydrocarbons (PAHs) and heavy metals are toxic compounds emitted from various anthropogenic sources and have a great effect on the human health as well as on the environment. Population living closer to the vicinity of an oil refinery may be at a greater risk of exposure to PAHs through inhalation, ingestion, and direct contact with the contaminated media. Atmospheric deposition of pollutants occur through both wet and dry deposition. Biomonitoring agent and passive monitoring technique were used in this study to evaluate heavy metal and PAH content in moss (Hyophila Involuta) collected from 30 sampling sites around the Sapugaskanda oil refinery with a 5 km radii. Sample collection was carried out in two separate days in September 2016. This study aimed to obtain a possible correlation between the atmospheric deposition of heavy metals and radial distribution pattern using epiphyte mosses collected from each sites. 16 PAHs were identified and quantified using High Performance Liquid Chromatography (HPLC). Bioaccumulation ability of seven heavy metals (Cr, Ni, Cd, Cu, Pb, Fe and Zn) were evaluated by Ion coupled plasma mass spectroscopy (ICP – MS). Contamination factor (CF) and Pollution loading index (PLI) were determined with reference to the background heavy metal concentration values. Maximum heavy metal accumulation was observed in a 2 km radii from the oil refinery. All the sampling sites showed CF>1 except for heavy metals Cr and Cd in few sampling sites. Pollution loading index for each radius showed a higher value with reference to the background levels. Low molecular weight (LMW) PAHs move away from the source (Sapugaskanda refinery) and high molecular weight (HMW) PAHs deposit near the emission source. Total concentration of carcinogenic PAHs varied from 0.25 to 13.75 ng/g. According to the study, total PAHs deposition observed around the vicinity of the oil refinery was in the range of 20 – 4398 ng/g. Due to the similar pollution sources, PAHs have often been found to coexist with environmental pollutants including heavy metals. Correlation studies were carried out statistically. There was a positive correlation between the Fe with Low molecular weight Polyaromatic hydrocarbons (LMW PAH) and High molecular weight polyaromatic hydrocarbons (HMW PAH) (p< 0.05). There were few correlations among several metals. Fe showed a positive correlation with metals such as Ni, Cu and Cd whereas Ni showed positive correlation with Cu and Cd. There was no significant correlation among other metals and PAHs. (p> 0.05).