1998年7月至9月，澳大利亚悉尼发生了一场饮用水质量危机。在分配系统收集的水样中反复观察到高浓度的隐孢子虫卵囊和贾第鞭毛虫囊肿，尽管没有检测到水传播疾病的增加。报告的囊肿和卵囊浓度范围从未检测到到到每100升成品水中有数千种寄生虫。根据这些监测数据，在九周内发布了三份沸水警告。政府下令进行正式调查，以调查污染的原因。作者参观了相关设施，发现提供监测数据的实验室存在重大质量保证和质量控制问题，使原生动物数据成为可疑数据。 此外，来自其他实验室的数据表明，原始报告存在错误。作者认为，在事实上不存在水质问题或对公共健康的威胁的情况下，依赖低质量的监测数据造成了水质危机。包括28个参考文献和表格。

A drinking water quality crisis occurred in Sydney, Australia, from July through September 1998. High concentrations of Cryptosporidium oocysts and Giardia cysts were repeatedly observed in water samples collected in the distribution system, although no increase in waterborne disease was detected. The reported concentrations of both cysts and oocysts ranged from nondetects to thousands of parasites per 100 L of finished water. Based on these monitoring data, three boil-water advisories were issued over a nine-week period. A formal government inquiry was ordered to investigate the cause of the contamination. The author visited the facilities involved and found that the laboratory providing the monitoring data had significant quality assurance and quality control problems, rendering the protozoan data suspect. Furthermore, data from other laboratories indicated the original reports were in error. In the author's opinion, reliance on poor-quality monitoring data created a water quality crisis when, in fact, no water quality problems or threats to public health existed. Includes 28 references, tables.