吡啶硫酮金属对华美盘管虫(Hydroides elegans)精子DNA的损伤效应

吡啶硫酮铜(Cu PT)和吡啶硫酮锌(Zn PT)在渗出型海洋防污涂料中的应用日益广泛,其生态毒性引起了人们的关注。本文以南海海域常见优势种——华美盘管虫(Hydroides elegans Haswell)为试验动物,采用彗星实验研究了吡啶硫酮金属对华美盘管虫精子细胞DNA的损伤情况。结果显示,低浓度(4μg·L~(-1)Cu PT或8μg·L~(-1)Zn PT)处理组的精子细胞,其"彗星"尾长、尾DNA含量及Olive尾矩都显著高于溶剂对照组(P0.05);较高浓度(8μg·L~(-1)或16μg·L~(-1)Cu PT,16μg·L~(-1)或32μg·L~(-1)Zn PT)处理组的精子细胞,其"彗星"尾长和尾矩多数显著高于溶剂对照组(P0.01)。此外,尾长和Olive尾矩在试验浓度范围内都呈现"效应-浓度"正相关。Cu PT为4μg·L~(-1)、Zn PT为8μg·L~(-1)时,对精子DNA造成轻度损伤;Cu PT为8μg·L~(-1)、16μg·L~(-1),Zn PT为16μg·L~(-1)、32μg·L~(-1)时,则达到了中度损伤的程度。可见吡啶硫酮金属具有较明显的海洋生态遗传毒性;另一方面,华美盘管虫精子细胞DNA对吡啶硫酮金属的胁迫呈现出较高的敏感性和效应-浓度相关性,在作为生态遗传毒性的生物指标方面具有潜在优势,进一步的研究将促进其在海洋重金属污染评价中的应用,特别是用于南海海洋环境的早期预警监测。

The Effects of Metal Pyrithione on Sperm DNA of Polychaete Hydroides elegans

The application of copper pyrithione (CuPT) and zinc pyrithione (ZnPT) are increasingly widespread in exudation antifouling coatings,and their potential ecotoxicity has attracted a plethora of concerns.In this paper,the effects of CuPT and ZnPT on sperm DNA damage of Hydroides elegans were investigated by comet assay.Results indicated that in groups with low concentration of CuPT (4 μg· L-1) or ZnPT (8 μg· L-1),the length of comet tail,DNA contents in tail,and comet Olive tail moment were significantly greater than that of the control (P＜0.05),and also those in the higher concentration groups (CuPT at 8 μg·L-1 or 16 μg·L-1,ZnPT at 16 μg·L-1 or 32 μg·L-1) were significantly greater than that of the control (P＜0.01).A positive "concentration-effect" relationship was observed within the concentration range of this experiment.When CuPT and ZnPT were at 4 μg· L-1 and 8 μg· L-1,respectively,DNA damage occurred in a slight degree,while at 8 μg· L-1 and 16 μg·L-1 CuPT or 16 μg·L-1 and 32 μg·L-1 ZnPT,moderate DNA damage was detected,indicating that CuPT and ZnPT could have obvious ecogenotoxicity in marine environment.In addition,the results also illustrated that Hydroides elegans sperm were sensitive to stress caused by CuPT and ZnPT,and therefore such test can be considered as a potential biomarker for ecogenotoxicity assessment of marine pollution caused by heavy metals,especially for early alert in the South China Sea.