Bioaccumulation of Dichlorodiphenyltrichloroethane (ddt) and Heavy Metals in the Benthic Polychaete, Nereis Succinea from a Typical Mariculture Zone in South China

of Oral Presentation ICMPE-8 Abstract of Oral Presentation O-1 BIOACCUMULATION OF DICHLORODIPHENYLTRICHLOROETHANE (DDT) AND HEAVY METALS IN THE BENTHIC POLYCHAETE, NEREIS SUCCINEA FROM A TYPICAL MARICULTURE ZONE IN SOUTH CHINA H Z Li, F Wang and J You State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China Strong evidence has indicated that dichlorodiphenyltrichloroethane and its metabolites (DDTs) and heavy metals are ubiquitous contaminants in the sediments from mariculture zones in South China, yet bioaccumulation potential and toxicological effects of those contaminants to benthic organisms were scarcely studied in this area. The current study investigated the bioaccumulation potential of sediment-bound DDTs and heavy metals in benthic polychaete, Nereis succinea from the sediments collected from an aquafarming zone in Hailing Bay, a typical mariculture zone along the southern coastal of China. The concentrations of DDT and its metabolites in sediment ranged from 120 to 4882 ng/g dry weight (dw), with the parent DDT accounting for 40-68%. The estuary sediments were co-polluted by heavy metals, and Cu (2.16-3.53 mg/kg dw) was the most abundant metal, followed by Zn (1.41-3.02 mg/kg dw) and Cr (1.56-2.58 mg/kg dw). The bioaccumulation potential of DDTs and heavy metals to benthic organisms were assessed by exposing N. succinea to the estuary sediments for 28 d. Body residues of DDTs in N. succinea were 371-1898 ng/g dw, and the percentages of parent DDT were 11-26%, which was about three times smaller than that in the sediments. The biota-sediment accumulation factors (BSAFs) of the parent DDT and its metabolites were all lower than 1, except for DDE which had BSAFs higher than 1 and reached 4 for one sediment. This suggested that the bioavailability of DDTs in these sediments were low and the biotransformation of DDT to DDE occurred in the organisms. For heavy metals, body residues of Zn (10.3-66.5 mg/kg dw) was significantly higher than that of Cu (5.37-10.7 mg/kg dw), followed by Cr (0.20-3.2 mg/kg dw). The different order of Cu and Zn concentrations in sediment and organism implied that sediment-bound Zn possibly had higher bioavailability to N. succinea than Cu, while the low BSAFs suggested low bioavailability of the heavy metals in the estuary sediments. ICMPE-8 Abstract of Oral Presentation O-2 BIOACCUMULATION OF POLY AROMATIC HYDROCARBONS (PAHS) BY DIFFERENT BENTHIC ORGANISMS IN THE CENTRAL ARABIAN GULF Y S Soliman, E Al Ansari, J Sericano and T L Wade Qatar University, Department of Biology and Environmental Science, P.O. Box 2713, State of Qatar Qatar University, Environmental Sciences Center, P.O. Box 2713, State of Qatar Texas A&M University, Geochemical and Environmental Research Group, College Spatial and temporal variability of levels of Poly Aromatic Hydrocarbons (PAHs) bioaccumulation by dominant benthic invertebrates were examined during the period of 2014-2015. Dominants benthic organisms samples were collected seasonally from thirteen locations in the coastal water of Qatar starting in the winter of 2014 and for four consequent seasons. Ten abundant benthic invertebrate species representing different trophic levels were selected to assess the spatial and temporal variability of PAHs bioaccumulations in the Qatar costal water. The species included gastropods, bivalves, and crustaceans with different trophic positions including carnivores, omnivores, herbivores and filter feeders. Samples were analyzed for 16 parent PAHs including low molecular weight parent PAHs (LPAHS) and high molecular weight parent PAHs (HPAHs), 18 alkyl homologs and dibenzothiophenes. Levels of PAHs in tissue residues are found to vary significantly with species, locations, seasons and also with distance from shore (P< 0.05). PAHs concentrations in tissues were significantly higher than those in sediments (P< 0.05), (30 < PAHs < 4000 ng.gm dry wt) indicating tendency of these persistent contaminants to bioaccumulate in the organisms. Bioaccumulation rate normalized to lipid content varied with location, species and also with size of organisms. The Highest levels of PAHs were associated with point sources with very few reports of levels higher than 1000 ng/gm. The trophic position of the organisms used in the measurements of tissue residues were determined using δN signatures. Significant correlations (P< 0.05) were found between PAHs tissue residues concentrations and signatures of carbon and nitrogen stable isotopes emphasizing the roles of trophic pathways on the uptake and bioaccumulation levels of individual PAHs in marine invertebrates. The knowledge from this study intended to assist PAHs monitoring and identification of potential sources to guide management decisions. The outcome of the study is expected to help the regulatory agency (Qatar Ministry of Environment) as well as Gulf organizations such as ROPME to improve environmental laws and set standards based on these studies. ICMPE-8 Abstract of Oral Presentation O-3 CHANGES IN SEDIMENT QUALITY AND MACROBENTHIC COMMUNITIES IN HONG KONG WATERS: A COMPARISON BETWEEN 2001 AND 2012 Z Wang, K M Y Leung, X Li and J W Qiu Department of Biology, Hong Kong Baptist University, Hong Kong, China The Swire Institute of Marine Science and School of Biological Sciences, The University of Hong Kong, Hong Kong, China Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China We will compare the sediment quality and macrobenthic community structure in Hong Kong waters from 2001 to 2012. This period is particular interesting because the Phase I of the Harbour Treatment Scheme, a large scale engineering project aiming to improve the water quality in Hong Kong, was completed at the end of 2001, and it is expected that the improvement in sediment quality and recovery of macrobenthic community would take several years to accomplish. We will analyse data sets obtained from a study commissioned by the Agriculture, Fisheries and Conservation Department in 2001, and a study commissioned by the Environmental Protection Department in 2012. The data sets encompassed 35 sediment and benthic sampling stations across all of the seven Water Control Zones in Hong Kong, allowing us to distinguish background shifts from changes due to the implementation of pollution control measures. We will compare several parameters that are related to sediment quality, including sediment particle size distribution, organic matter, total Kjeldahl nitrogen and total phosphorus content, as well as the macrobenthic communities using univariate techniques and cluster analysis and multi-dimensional scaling ordination. We expect no substantial changes in a majority of the Water Control Zones that were not directly affected by the Harbour Treatment Scheme, significant recovery in Tolo Harbour and the eastern side of Victoria Harbour where sewage collection had reduced the direct discharge, and worsening of sediment and macrobenthic structure in the western side of Victoria Harbour where the treated effluent was discharged through a short submarine outfall. Overall, our analyses will provide a new baseline of sediment and macrobenthic community structure in Hong Kong, and establish an excellent example of faunal recovery from eutrophication in subtropical waters. ICMPE-8 Abstract of Oral Presentation O-4 TRACE METAL CONCENTRATIONS IN SEDIMENTS AND BIOTA OF THE SOUTH-EAST COAST OF NSW, AUSTRALIA WITH AN EMPHASIS ON METALS, Sn, Cu AND Zn USED AS ANTIFOULING AGENTS. “HOW PRISTINE IS THE PRISTINE SOUTH COAST?” I R McVay, W A Maher and F Krikowa University of Canberra, Bruce ACT 2601 Australia Tin, copper, zinc, cadmium, lead, selenium, cobalt, chromium, nickel and mercury concentrations were measured in sediments, and three organisms, the oyster, Saccostrea glomerata, a sediment dwelling gastropod, Batillaria australis and a rocky intertidal gastropod, Austrocochlea porcata, at 12 locations along the south coast of NSW Australia from Batemans Bay to Twofold Bay during 2009. Mean concentration in sediments were tin 0.05-1.8 g/g; copper 0.05-1,626 g/g, zinc 2.6-4,958 g/g, cadmium 0.05-5.2 g/g , lead 0.05-21.8 g/g, selenium 0.05-10.4 g/g, cobalt 0.05-5.92 g/g, chromium 0.05-13.6 g/g, nickel 0.91-22.4 g/g and mercury 0.05-0.17 g/g. Several locations exceeded the ANZECC/ARMCANZ (2000) interim sediment quality guidelines levels for copper, zinc, cadmium, nickel and mercury. Some sites had elevated tin concentrations that may potentially exceed guideline levels for Tributyltin (TBT). S. glomerata, B. australis and A. porcata generally had low mean concentrations of tin 0.05-1.42 g/g; copper 0.05-550 g/g, zinc 5-2363 g/g, cadmium 0.05-4.6 g/g , lead 0.0510.4 g/g, selenium 0.05-4.5 g/g, cobalt 0.05-5.5 g/g, chromium 0.05-9 g/g, nickel 0.05-18.8 g/g and mercury < 0.05 g/g respectively approaching background concentrations. Oyster have cadmium and lead concentrations below Australian food standards code. S. glomerata, and A. porcata mean tin concentrations were significantly correlated across locations indicating similar metal uptake processes. There were no significant correlations between trace metal concentrations in sediment and in organisms within locations, and no relationship with levels of boating activity and suspected antifouling contamination. Although not pristine, the low levels of trace metal contamination in gastropods and oysters indicate that this region is suitable for mariculture. ICMPE-8 Abstract of Oral Presentation O-5 APPLICATION OF RESPONSE SURFACE METHODOLOGY FOR OPTIMIZATION OF BIOSTIMULANT BALL FOR STABILISATON OF CHROMIUM AND ZINC IN CONTAMINATED COASTAL SEDIMENT B Subha, J H Woo and Y C Song Department of Environmental Engineering, Korea Maritime and Ocean University, South Korea Department of Nuclear Power Equipment Research Center, Korea Maritime and Ocean University, South Korea Numerous contaminants introduced to coastal sediment in urban area are accumulated in marine sediment and it significantly affect marine aquatic environment. The aim of present study is to optimize the bioremediation of slow releasing biostimulant ball (BSB) for stabilisation of the heavy metals (Cr, Zn) present in the sediment using Response Surface Methodology (RSM). The effective variables such as BSB size (1-5cm), distance (1-10cm) and month (1-4 months) on Cr and Zn stabilisation were investigated. The analyses of variance (ANOVA) and coefficient determination (R) of Cr and Zn were 0.9650 and 0.9666. The maximum stabilization percentages of Cr and Zn were 15.8% and 79.5%, were observed at a 3 cm ball size, 5.5 cm distance, and a period of 4 months; these values are the optimum conditions for effective remediation of contaminated coastal sediment. The determination coefficient of the R value suggests that more than 96.50%, and 96.66% of the variance is attributable to the variables of Cr and Zn. This result revealed that the BSB is effective for Cr and Zn stabilisation in coastal sediment.