Wan Ruslan Ismail

Distribution, Sources Identification, and Ecological Risk of PAHs and PCBs in Coastal Surface Sediments from the Northern Persian Gulf

ABSTRACT Hormozgan Province plays a vital role in fishery, petroleum, and industrial activities in southern Iran. However, no comprehensive studies on organic pollution have been performed. PCBs and PAHs were analyzed in surface sediments from areas receiving industrial (nine sites), river (one site), and urban (two sites) effluents. The sediment samples were collected in March and September 2010 (in dry and wet seasons) at the highest tidal time. The overall pollution level of PCBs ranged from 2.5 ± 0.8 to 462.0 ± 206.7 ng/g dry weight. CB153 congener dominated in most of the sediment samples. Congener profiles of PCBs showed close similarity with formulations of commercial products such as Aroclor 1260 and 1254 g. A wide range of 55.3 to 1231.6 ng/g dry weight was detected for ∑PAHs. Results of PCA and PCA-MLR tests confirmed both petrogenic and pyrogenic origins for PAH pollution. The higher means of ∑PAHs and ∑PCBs in industrial and urban wastewaters were found near the shore, evidencing the role of these wastewaters in the PAH and PCB contamination in Hormozgan sediment. The concentrations of PAHs and PCBs in detected hotspots exceed the U.S. NOAA sediment quality guidelines.

Total petroleum hydrocarbons in sediments from the coastline and mangroves of the northern Persian Gulf.

To provide baseline information for the marine ecosystem of Hormozgan province, the distribution of petroleum hydrocarbons was evaluated in 52 stations involved in the mangrove and coastline ecosystem. Coastline sampling sites included areas facing harbor, river, domestic and industrial discharge. Sediment samples were analyzed based on ultraviolet fluorescence spectroscopy. Petroleum hydrocarbons showed narrow variations ranging from non-detectable (ND) to 1.71 and from 0.2 to 0.63μg/g dry weight for coastline and mangrove sediments, respectively. The detected concentrations for total petroleum hydrocarbons were lower than guideline values for ecological risk. Furthermore, the minimum environmental risk was confirmed by background levels for the Persian Gulf, the Sea of Oman, and detected values for reference areas. The results were regarded as background data in the studied area, and, considering the rapid expansion of activities related to the petroleum industry in Hormozgan province, the continuous monitoring of pollutants is recommended.

Health Risk of PCBs and DDTs in Seafood from Southern Iran

ABSTRACT Levels of polychlorinated biphenyls (PCBs) congeners and dichlorodiphenyltrichloroethane and its metabolites (DDTs) were measured in 18 species of fish, crab, shrimp, and bivalve samples collected from the northern region of the Persian Gulf in Iran. The levels of ∑PCBs varied from 259.92 ± 31.04 ng/g to 1648.88 ± 176.96 ng/g in lipid weight. CB118 showed the highest concentration. ∑DDT variations ranged from ND to 570.45 ± 806.74 ng/g in lipid weight. Health risk was assessed by estimating both dietary intakes and screening values (SVs). Daily intake levels were much lower than the Food and Agriculture Organization (FAO)/World Health Organization (WHO) standards for PCBs and DDTs. Based on an average bodyweight of 73 kg and consumption rates of 0.055 kg/person. day, the SVs for the carcinogen and non-carcinogen effects of PCB and DDT were calculated. Average concentrations of PCBs and DDTs showed that the levels of PCBs exceeded the established SV for carcinogens. This finding suggests the need to enhance risk management regarding seafood consumption through public advisory.

Residual concentration of PAHs in seafood from Hormozgan province, Iran : human health risk assessment for urban population.

This study is to determine the concentrations of sixteen poly aromatic hydrocarbons in eighteen pooled samples of fish, shrimp, crab and bivalve from markets of Hormozgan province, Iran. The poly aromatic hydrocarbon levels varied from 16 ± 8.4 to 28.18 ± 3.74 ng/g wet weight. The investigated samples were classified as minimally contaminated. Distribution patterns showed that PAHs with 4, 5 and 6 rings dominated, confirming the pyroge nic source of detected PAHs. Fish contributed more than other biota groups in transforming of PAHs to Hormozgan Province people. The average of B (a)P eq)values for the studied biota was 2.71 ± 2.28 ng/g that was greater than calculated local screen value. This finding was implemented in poor quality of studied biota and necessity for risk management.

Utilisation of natural cellulose fibres in wastewater treatment

Water safety and security are global problems. Indeed, researchers have taken this matter seriously and have begun to find alternative ways of treating wastewater. The conventional method for treating wastewater has been found to be uneconomical, and the polymeric materials used were not environmentally friendly. Biosorption techniques and mechanisms have been shown to be an effective alternative to replace conventional technologies. As agricultural waste is abundantly available, it has been chosen as the best starting material to produce biosorption material. Also, the hydroxyl functional groups in cellulose act as important parts to produce better absorbent materials. This review has explored the role of natural fibres as adsorbents for wastewater treatment while at the same time, for the removal of adsorbates such as oil, dyes, heavy metals, ionic compounds, and others as reported in the literature. Also investigated in this study, were the different modification types used to enhance the fibres and the mechanism of contaminant removal by the absorbents. Lastly, the physical forms of adsorbates and common types of effluents treated using natural fibres were examined and discussed.

Suspended sediment and phosphorus budget and trophic status of Bukit Merah Reservoir, Perak, Malaysia

Abstract Bukit Merah Reservoir (BMR) is one of the 51 impoundments in Malaysia. BMR is the oldest reservoir built in the early 1900s originally to store water for irrigation, but nowadays its functions include also flood control and water supply. Nowadays, it is threatened by land use change in the upper catchments and surrounding activities, which feeding eroded material and chemicals into the reservoir. Suspended sediment, as well as, nutrient fluxes into BMR are becoming an increasing threat to the reservoir, as its sedimentation and eutrophication accelerate. This paper discusses our study on the BMR carried out between March 2008 and April 2009 to assess the water quality status, and to determine the sediment and Total Phosphorus (TP) influx into the south pool lake. An estimated amount of suspended sediment fluxes of about 2,900 t year−1 came from the north pool lake (18%) and 12,900 t year−1 from the main Kurau River inlet (82% of the total input to the BMR). Of these total sediment input (nearly 15,800 t) about 5,600 t (36%) of the total sediment influx was trapped in the BMR. TP influx was about 18.8 t year−1 and about 7 t (37%) was trapped in the reservoir. The amount sediment and TP stored in the BMR affect the water quality of the lake, therefore the mean trophic state of the lake is eutrophic (TSI of 54.4) related to high productivity. Increasing sediment input into the reservoir has affected the reservoir volume and frequent flooding down-stream of the reservoir during rainy seasons, while eutrophication has caused the lake water quality deterioration.

Comparing typhoon intensity prediction with two different artificial intelligence models

In typhoon-prone areas, in order to announce catastrophe warnings in advance accurate storm-intensity prediction is essential. In this study, forecasting typhoon intensity with their characteristics has been supported by two different artificial intelligence methods, a simple artificial neural network (ANN) and an adaptive neuro-fuzzy inference system (ANFIS) based on genetic algorithm (GA). The data used throughout this paper are from the reanalysis data set of the National Centers for Environmental Prediction and the best track database of the National Oceanic and Atmospheric Administration. The typhoons selected for this study happened during 1985–2008 over the South China Sea. By comparing the results from these two methods, their advantages and disadvantages were investigated. The results of the study confirm the superiority of the ANFIS-GA method, because its root mean square error was 3.78, which is significantly lower than the value of 6.11 for the ANN method in the best experiments. Considering the literature in typhoon intensity prediction by ANN and ANFIS models, the contribution of this paper is to investigate whether or not these methods are able to forecast typhoon intensity. The study represents that the ANFIS model can produce more applicable predictions for typhoon intensity than the ANN model.

Spatial and temporal variations of sedimentation rate in the Timah Tasoh Water Reservoir, Perlis, Malaysia.

Spatial and temporal variations of sedimentation rate in the Timah Tasoh Water Reservoir, Perlis, Malaysia Human activities such as logging, land conservation, road construction and other disturbances in watersheds will increase erosion rate and thus the amount of sediment transported into the river that reaches lakes, reservoirs and sea. Accelerated sedimentation rate in the reservoir can significantly reduce a reservoirs surface area, eliminating wetland area surrounding the reservoir and shallow the areas near the shore of the reservoir. A study of sedimentation rate in the Timah Tasoh water reservoir was carried out from May 2001 to April 2002 by means of sediment traps. The aim of this study is to determine the spatial and temporal pattern of sedimentation rates in the reservoir. The sediment traps were installed at five different locations in the reservoir and replaced every month. Gross sedimentation rates measured in the sediment traps vary from about an average of 1.4 kg/m2/month or 16.3 kg/m2/yr in the deepest part of the reservoir to about 79.2 kg/m2/yr (monthly average of 6.6 kg/m2/month) and 47.1 kg/m2/yr (monthly average of 3.9 kg/m2/month) near the inlet of the Pelarit River and the Tasoh River respectively. The sedimentation rate near the Pelarit River and the Tasoh River inflow is correlated with the water and suspended sediment discharge in the river, owing to its proximity to the rivers and the flooding effect, mainly during the wet season. The sedimentation rate decreases southward along the reservoir, as a result of increasing distance from the river mouth. The total suspended sediment load of the Upper Pelarit River and the Jarum River flowing into the reservoir is 11.4 × 103 ton/year and 5.41 × 103 ton//year respectively. Analiza przestrzenna i czasowa zmienności ilości sedymentu w zbiorniku Timah Tasoh, Perlis w Malezji Na podstawie szczegółowych łapaczkowych pomiarów terenowych przedstawiono zmiany przestrzenne i czasowe (2001-2002) ilości sedymentu w zbiorniku wodnym Timah Tasoh w Malezji. Łapaczki umieszczone w pięciu punktach zbiornika opróżniano co 5 miesięcy. Zmiany ilości sedymentu wykazano liczbowo na tle ilości dostarczanego rumowiska do zbiornika z rzek Pelarit oraz Jarum.

Mapping of total suspended solids in reservoir using images captured by a conventional digital camera from a low-altitude light aircraft

The feasibility of using digital camera imagery for estimating the concentration of total suspended sediments (TSS) in the Timah Tasoh reservoir was investigated. Digital images were captured from a low-altitude light aircraft. Three selected images were mosaiced to produce bigger image of the study area. Atmospheric corrections and mosaic sincronourization were performed by using the average digital number of grass in the images as a reference value. Water samples were collected simultaneously with the airborne image acquisition and later analyzed in the laboratory. The color mosaic image was separated into three bands assigned as red, green and blue bands and analysis separately. The digital numbers for each bands corresponding to the ground-truth locations were extracted and used for calibration of the water quality algorithm. A single band second order polynomial algorithm was used in this study due to limited ground-truth data. The calibrated algorithm was used to generate the water quality maps. The proposed algorithm can estimate TSS concentration with linear correlation coefficient square (R2) of 0.98.

Concentrations and Source Identification of Polycyclic Aromatic Hydrocarbons (PAHs) in Mangrove Sediments from North of Persian Gulf

The concentrations of 16 Environmental Protection Agency (EPA) priority polyaromatic hydrocarbons (PAHs) were quantified in surface sediments from Hormozgan Province mangroves, south of Iran in dry and wet seasons. Sampling stations were selected in Laft and Khamir mangroves with international importance. Polyaromatic hydrocarbons varied from 75.24 ± 11.24 to 581.94 ± 637.39 ng/g dry weight basis. Pollution sources and their contribution for polyaromatic hydrocarbons pollution in sediments of Hormozgan mangroves were appointed based on molecular ratios and statistical methods, including principal components analysis (PCA) and multiple linear regression/principal components analysis (PCA/MLR) tests. Both of pyrogenic and petrogenic sources contributed in detected concentrations of PAHs. Contribution percentages of pyrogenic and petrogenic origins were estimated at 73.20 and 26.79%, respectively. Temporal variations showed that sediments contained higher levels of ∑PAHs in wet season than dry time. However, the mean detected ∑PAHs was lower than international quality guidelines; the high concentration of PAHs was found in Laft mangrove, suggesting the presence of PAH polluted localized area.