Risk assessment for the daily intake of polycyclic aromatic hydrocarbons from the ingestion of cockle (Anadara granosa) and exposure to contaminated water and sediments along the west coast of Peninsular Malaysia

The concentration of carcinogenic polycyclic aromatic hydrocarbons （c-PAHs） present in the sediment and water of Peninsular Malaysia as well as in the cockle Anadara granosa was investigated. Samples were extracted and analysed with gas chromatographymass spectrometry. The concentrations of total carcinogenic polycyclic aromatic hydrocarbons （t-PAHs） were measured between 0.80±0.04 to 162.96 ±14.74 ng/g wet weight （ww） in sediment, between 21.85± 2.18 to 76.2± 10.82 ng/L in water samples and between 3.34 ±0.77 to 46.85 ± 5.50 ng/g ww in the cockle tissue. The risk assessment of probable human carcinogens in the Group B2 PAHs was calculated and assessed in accordance with the standards of the United States Environmental Protection Agency （US EPA）. Case I in the toxicity assessment analysed the cancer risk to consumers of Malaysian blood cockle. Case II assessed the risk of cancer from exposure to PAHs from multiple pathways. The average cancer risk of case I and case II were found to be classifiable as unsafe according to the US EPA standard. The cancer risk due to c-PAHs acquired by the ingestion of blood cockle was （8.82 ± 0.54） × 10^ 6 to （2.67 ± 0.06） × 10^-2, higher than the US EPA risk management criterion. The non-cancer risks associated with multiple pathways in Kuala Gula, Kuala Juru and Kuala Perlis were higher than the US EPA safe level, but the non-cancer risk for eating blood cockle was below the level of US EPA concern.

Coastal oceanographic processes associated with blood cockle (Anadara granosa) induce spawning season in Kapar, Selangor, Malaysia

Study on coastal processes in Kapar waters was conducted from 2008-2016.The aim of this study is to identify potential blood cockle(Anadara granosa)induce spawning ground based on physical intermittency.A total of 132 sampling stations were recorded.A thermal power station situated 2 km away is discharging treated warm water(<40℃)on to the open sea causing the Sea Surface Temperature at near-by cockle culture to intermittent between 31-34℃ while the temperature at the bottom(at 6-8 m Mean Sea Level,MSL)is constant between 29.5℃ and 30.5℃.The results suggested that Kapar waters have two seasons of low waters annually(January-March and June-September,respectively)and the Lowest Astronomical Tide(LAT)occur in late January-February while Great Diurnal Tide is observed on the same period.The bathymetry suggested the present of deep water(6-8 m,MSL)towards the end of cockle culture lot which is closed to merchant shipping lane near Port Klang.Based on water elevation,an area of 255.4 ha within cockle culture lots were identified to have this bottom temperature intermittency(29.5-34.0℃)during its GT and it associated with cockle induce spawning condition.But this area was left out for cockle culture due to its typical depth(>3 m MSL)which prevents cockle farmers from harvesting due to their maximum of 3 m long hand dredge.Thus,this information could be useful for cockle sustainable management plan in near future.

泥蚶34个EST-SSR标记的开发及在格粗饰蚶中的通用性检测

利用泥蚶转录组高通量测序、拼接获得的大量EST序列开发SSR标记,在1 123条EST序列里筛查到73条含有SSR位点的EST序列,其中54个位点适合设计引物,在位点两侧设计引物并进行PCR扩增。结果显示,46对引物获得稳定扩增的位点,引物在泥蚶奉化群体的多态性检测中发现,有34对引物表现出多态性,共扩增出122个等位基因,各位点的等位基因数Na为2～7个,平均每个位点产生3.59个等位基因,观测杂合度Ho、期望杂合度He、多态信息含量PIC范围分别为0.000～0.600、0.078～0.771、0.106～0.718;Hardy-Weinberg平衡检测显示,13个位点偏离了平衡状态;用Nr和Swiss-Prot蛋白质数据库对含有多态性SSR的EST进行了基因注释,25个SSR位点来自注释基因序列。将34对泥蚶多态性SSR引物在格粗饰蚶中进行了通用性检测,结果有11对成功扩增,8对表现为多态,通用率为23.53%,这些通用引物可用于两种蚶的遗传多样性评价、系统进化分析、比较作图和基因发掘等研究。

毛蚶、魁蚶和泥蚶核糖体DNA转录间隔区的RFLP分析

对毛蚶、魁蚶和泥蚶核糖体DNA转录间隔区(ITS区)进行限制性片段长度多态性(RFLP)分析发现,6种限制性内切酶(HaeⅢ,HhaⅠ,HpaⅡ,RsaⅠ,Sse9Ⅰ和TaqⅠ)均能将泥蚶与毛蚶及魁蚶区别开来,但未发现毛蚶和魁蚶间特异性的RFLP标记。对酶切图谱进行的数理分析结果显示,毛蚶与魁蚶之间的净遗传距离Pnet值为0,而泥蚶与毛蚶、泥蚶与魁蚶之间的Pnet值均为0.0797;泥蚶群体内检测到5种酶切复合单倍型,核苷酸多样性指数π值为0.0008外,而毛蚶和魁蚶群体内为相同的1种复合单倍型,π值均为0。

泥蚶及菲律宾蛤仔对环境中氨的耐受力

本文对泥蚶成贝、幼贝,菲律宾蛤仔成贝、幼贝的未离解氨氮 168h LCD_(50),EC_(50)(降低耐低氧环境能力50%的浓度)进行了试验,并对氨的致死和亚致死浓度与内湾养虾水域(乳山东湾)、试验虾池及利用虾池水的试验贝池底质环境的氨氮水平作了概略评价。

泥蚶人工育苗立体附苗技术的研究

采用不同附着基，进行泥蚶人工育苗中立体平面附着与池底平面附着的对比试验。结果：立体平面附着基使单位水体出苗量增加了3．4～5．3倍；透明和黑色波纹板附着效果较好，沙盘次之，扇贝盘和棕帘最差；底铺黑色有孔波纹板，好于透明波纹板。并发现泥蚶一般在大潮期间产卵，光照800～1000Lx下幼虫发育未见异常。