The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol.

Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608 μg Cd L⁻¹). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20 ± 1 °C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56 days were reproducible between laboratories (68 < EC_50–56d < 124 μg L⁻¹) and were consistent with literature data. EC_50–56d and EC_10–56d values were comprised within a factor of 1.8 and 3.6, respectively, which is in the range of acceptable variation defined for reference chemicals in OECD test guidelines for invertebrates. The inter-laboratory reproducibility coefficient of variation (CV) for the Cd LC_50–56d values was 8.19%. The inter-laboratory comparison of fecundity within the controls gave a CV of 29.12%, while exposure to Cd gave a CV of 25.49% based on the EC_50–56d values. The OECD has acknowledged the success of this prevalidation exercise and a validation ring-test involving 14 laboratories in Europe, North- and South-America is currently being implemented using four chemicals (Cd, prochloraz, trenbolone and tributyltin).

经合组织（OECD）的测试指南制定计划已在2011年扩展，以建立部分生命周期协议，以评估化学品对几种软体动物物种的生殖毒性，包括大蜗牛田螺（Lymnaea stagnalis）。在本文中，我们总结了该物种繁殖测试的标准方案草案，并介绍了使用该方案在56天的预验证环试验中获得的比对结果。

七个欧洲实验室使用暴露于标称浓度的氯化镉（53至608μgCd L ^-1）下的Renilys®菌株培养的蜗牛进行了半静态测试。通过分析确定测试溶液中的Cd浓度，以确认所有实验室中金属暴露浓度的准确性。在测试期内符合理化和生物学有效性标准（即溶解氧含量> 60％ASV，水温20±1°C，对照蜗牛存活率> 80％和对照蜗牛繁殖力> 8个鸡蛋/蜗牛）。所有实验室都使用拟议的方案草案一贯证明了镉在蜗牛中的生殖毒性。在实验室之间重现56天后的生殖力有效浓度（68 <EC _50–56d <124μgL ^-1），并且与文献数据一致。EC _50–56d和EC _10–56d值分别在1.8和3.6的范围内，这在OECD无脊椎动物测试指南中为参考化学品定义的可接受范围内。Cd LC _50–56d值的实验室间重现性变异系数（CV）为8.19％。实验室间对生殖力进行比较，对照组的CV为29.12％，而暴露于Cd的CV为25.49％（基于EC _50-56d）价值观。经合组织已经确认了这种预验证工作的成功，目前正在使用四种化学药品（镉，丙草胺，群勃龙和三丁锡）在欧洲，北美和南美的14个实验室进行验证环试验。