Tire emissions have emerged as an environmental contaminant of concern. To fully understand their effects to biota, research is needed from different stages of a tire’s lifecycle. In this study we exposed freshwater Hyalella azteca to tire wear particles (TWPs) as particle suspensions or their respective chemical leachates (the chemicals released from tire particles into water) from a pristine (P-TWP) and worn (W-TWP) tire of same make and model. Acute and long-term toxicity experiments on H. azteca showed that P-TWP suspensions were more toxic than W-TWP suspensions with estimated LC₅₀ values of 364 ± 64 particles (0.19 ± 0.03 g L⁻¹) and 3073 ± 211 particles (0.91 ± 0.06 g L⁻¹), respectively. However, leachates from W- and P-TWPs appeared equally toxic, but did not conform to a sigmoidal dose-response pattern and LC₅₀ values could not be derived. In long-term tests (21 d) P-TWP suspensions showed no significant effects on H. azteca mortality (p = 0.970) or reproduction (p = 0.123), but growth was significantly reduced (p = 0.003) at the highest concentration tested (250 particles mL⁻¹ or 0.127 g L^-1). Chemical analysis of both particle types and their leachates showed that four compounds, benzothiazole, 1-indanone, aluminum and zinc, consistently leached from TWPs into water. Analysis of the two TWPs showed a difference in the concentration of the various compounds. Specifically, P-TWPs contained significantly more 1-octanethiol, phenanthrene, anthracene and aluminum than W-TWPs, suggesting that they are possible candidates for the increased toxicity observed following P-TWP exposure.

轮胎排放已成为令人关注的环境污染物。为了充分了解它们对生物群的影响，需要从轮胎生命周期的不同阶段进行研究。在这项研究中，我们将淡水阿兹特克鬣狗暴露于轮胎磨损颗粒（TWP）中，作为颗粒悬浮液或其各自的化学浸出液（从轮胎颗粒释放到水中的化学物质），来自原始（P-TWP）和磨损（W-TWP）轮胎相同的品牌和型号。对H. azteca的急性和长期毒性实验表明，P-TWP 悬浮液比 W-TWP 悬浮液毒性更大，估计 LC ₅₀值为 364 ± 64 个颗粒（0.19 ± 0.03 g L ^-1 ）和 3073 ± 211 个颗粒（分别为0.91±0.06gL ^-1 )。然而，W-TWP 和 P-TWP 的渗滤液似乎具有相同的毒性，但不符合 S 形剂量反应模式，并且无法得出 LC ₅₀值。在长期测试（21 天）中，P-TWP 悬浮液对阿兹台克人死亡率（p = 0.970）或繁殖（p = 0.123）没有显着影响，但在最高测试浓度下生长显着降低（p = 0.003） (250个颗粒mL ^-1或0.127 g L ^-1 )。对两种颗粒类型及其浸出液的化学分析表明，苯并噻唑、1-茚满酮、铝和锌这四种化合物始终从 TWP 浸出到水中。两种 TWP 的分析显示各种化合物的浓度存在差异。具体而言，P-TWP 比 W-TWP 含有明显更多的 1-辛硫醇、菲、蒽和铝，这表明它们可能是 P-TWP 暴露后观察到的毒性增加的候选者。