By employing external fertilization (broadcast spawning) as a mating strategy, the gametes and subsequent fertilization of various marine invertebrates are directly subjected to pollution. Although microplastics (MPs) are ubiquitous in marine environments, their potential effects on the fertilization of broadcast spawners remain largely unknown. Therefore in this study, the impacts of polystyrene MPs on the fertilization success of broadcast spawning bivalve (Tegillarca granosa) were investigated. In order to reveal the underlying mechanisms affecting fertilization, the sperm swimming performance, sperm ATP status, sperm viability, DNA integrity, gamete collision probability, gamete fusion efficiency, enzymatic antioxidants, and key ion transport enzyme activities were analyzed. The results showed that MPs weakened the sperm swimming performance through reducing ATP production and cell viability, thus leading to the decreased probability of gamete collision. Furthermore, MPs affected ion transport in the gametes by inducing oxidative stress, which resulted in gamete fusion failure. In conclusion, this study demonstrates that MPs could significantly decrease the fertilization success of T. granosa through reducing gamete collision and lowering gamete fusion efficiency.

通过采用外部受精（广播产卵）作为交配策略，各种海洋无脊椎动物的配子和随后的受精直接受到污染。尽管微塑料 (MPs) 在海洋环境中无处不在，但它们对广播产卵器受精的潜在影响仍然很大程度上未知。因此在本研究中，聚苯乙烯 MPs 对播种产卵双壳贝 ( Tegillarca granosa ) 受精成功的影响) 进行了调查。为了揭示影响受精的潜在机制，分析了精子游泳性能、精子 ATP 状态、精子活力、DNA 完整性、配子碰撞概率、配子融合效率、酶抗氧化剂和关键离子转运酶活性。结果表明，MPs通过降低ATP的产生和细胞活力来削弱精子的游泳能力，从而导致配子碰撞的概率降低。此外，MPs 通过诱导氧化应激影响配子中的离子转运，从而导致配子融合失败。总之，本研究表明，MPs 可以通过减少配子碰撞和降低配子融合效率来显着降低T. granosa的受精成功率。