珠江口担杆岛附近海域底栖腹足类重金属含量及评价

EVALUATION ON THE HEAVY METAL CONTENTS IN BENTHIC GASTROPODS FROM MARINE AREA NEAR DANG GANG ISLANDS

对分布于珠江口担杆岛附近海域的 17种底栖腹足类重金属的含量进行测定 ,结果显示 :所有种类的整体软体组织中所测得的Cu、Zn、Pb、Ni和Sn的含量都低于香港 (PHMSO)和广东省(MOPAS)对海产品管理的规定标准 .7种腹足类体内的Cd含量和 12种腹足类体内Cr含量分别超过PHMSO评价标准 (2 0 0 μg/g和 1 0 0 μg/g) ;仅 3种腹足类体内Cd含量和 5种腹足类体内Cr含量分别超过MOPAS评价标准 (5 5 0 μg/g和 5 5 0 μg/g) ;4种腹足类体内的Sb含量略超过PHMSO评价标准 (1 0 0 μg/g) .结果还表明 ,Cd、Pb、Cr和Sb含量随腹足类整体体质量的增加而增加 ,而Cu和Zn在腹足类体内的含量与个体质量成反比 .Cu、Zn、Pb、Ni、Sb和Sn含量在腹足类不同器官组织中的分布为 :肝脏 >肾脏 >性腺 >鳃 >足 (P <0 0 1) ;而Cd和Cr含量的分布则为 :肾脏 >肝脏 >性腺>鳃 >足 (P <0 0 1) .

Concentrations of heavy metals were determined in 17 species of benthic gastropods collected from the marine area near Dang Gang Islands of Pearl River estuary. The results indicate that Cu, Zn, Pb, Ni and Sn concentrations in 17 species of gastropods are within the local regulatory limits of Hong Kong (PHMSO) and Guangdong Province (MOPAS). However, 7 and 12 species of gastropod exceed the PHMSO levels of Cd (2 μg/g) and Cr (1 μg/g) respectively, while only 3 and 5 species of gastropods exceed the MOPAS levels of Cd (5 5 μg/g) and Cr (5 5 μg/g) respectively; 4 species of gastropods exceed the PHMSO levels of Sb (1 μg/g). Good correlation was observed for metal concentrations in soft tissues with the whole body weight of gastropods, except Ni and Sn. Small gastropods (whole body weight basis) has higher Cu and Zn levels than what of larger ones. However, larger individuals have high levels of Cd, Pb, Cr and Sb concentrations. Heavy metal concentrations of different tissues in gastropods are also significantly different (P<0 01). In general, kidney or liver tissue have the highest proportion of metal contents (20%-76%) as compared with other tissue parts (gonad, gill, and food), except for Cu, which shows the highest level in gill tissues. Zinc, Pb, Ni, Sb and Sn concentrations in the tissues generally decrease in the relative order as follows: liver> kidney> gonad>gill>food, while poisonous metals such as Cd and Cr concentrations in the tissues generally decrease in the relative order as follows: kidney >liver> gonad>gill>food.