Soil and Water Science Department, University of Florida, 408 Newell Hall, Gainesville, FL 32611, United States.
Sci Total Environ. 2013 Jan 1;442:437-44. doi: 10.1016/j.scitotenv.2012.10.007. Epub 2012 Nov 24.
Triclocarban (TCC) is monitored under the USEPA High Production Volume (HPV) chemical program and is predominantly used as the active ingredient in select antibacterial bar soaps and other personal care products. The compound commonly occurs at parts-per-million concentrations in processed wastewater treatment residuals (i.e. biosolids), which are frequently land-applied as fertilizers and soil conditioners. Human and ecological risk assessment parameters measured by the authors in previous studies were integrated with existing data to perform a two-tiered human health and ecological risk assessment of land-applied biosolids-borne TCC. The 14 exposure pathways identified in the Part 503 Biosolids Rule were expanded, and conservative screening-level hazard quotients (HQ values) were first calculated to estimate risk to humans and a variety of terrestrial and aquatic organisms (Tier 1). The majority of biosolids-borne TCC exposure pathways resulted in no screening-level HQ values indicative of significant risks to exposed organisms (including humans), even under worst-case land application scenarios. The two pathways for which the conservative screening-level HQ values exceeded one (i.e. Pathway 10: biosolids➔soil➔soil organism➔predator, and Pathway 16: biosolids➔soil➔surface water➔aquatic organism) were then reexamined using modified parameters and scenarios (Tier 2). Adjusted HQ values remained greater than one for Exposure Pathway 10, with the exception of the final adjusted HQ values under a one-time 5 Mg ha(-1) (agronomic) biosolids loading rate scenario for the American woodcock (Scolopax minor) and short-tailed shrew (Blarina brevicauda). Results were used to prioritize recommendations for future biosolids-borne TCC research, which include additional measurements of toxicological effects and TCC concentrations in environmental matrices at the field level.
三氯卡班（TCC）受美国环保署高生产量（HPV）化学计划监管，主要用作某些抗菌皂和其他个人护理产品的活性成分。该化合物通常以百万分之几的浓度存在于经过处理的废水处理残留物（即生物固体）中，这些残留物经常作为肥料和土壤改良剂施用于土地。作者在之前的研究中测量的人类和生态风险评估参数与现有数据相结合，对土地施用生物固体携带的 TCC 进行了两级人类健康和生态风险评估。扩大了《第 503 部分生物固体规则》中确定的 14 种暴露途径，并首次计算了保守的筛选水平危害系数（HQ 值），以评估人类和各种陆地和水生生物（第 1 层）的风险。大多数生物固体携带的 TCC 暴露途径没有导致筛选水平 HQ 值表明暴露生物（包括人类）存在重大风险，即使在最坏情况下进行土地施用。两种保守的筛选水平 HQ 值超过 1 的生物固体携带 TCC 暴露途径（即途径 10：生物固体➔土壤➔土壤生物➔捕食者，以及途径 16：生物固体➔土壤➔地表水➔水生生物），然后使用修改后的参数和情景（第 2 层）重新检查。对于暴露途径 10，调整后的 HQ 值仍然大于 1，除了一次性 5 Mg ha(-1)（农业）生物固体施用量情景下美国木鸭（Scolopax minor）和短尾鼩鼱（Blarina brevicauda）的最终调整 HQ 值。结果用于确定未来生物固体携带 TCC 研究的建议的优先级，包括在田间水平对环境基质中的毒理学效应和 TCC 浓度进行更多测量。
