E . coli is a bacterium present in the gut of humans and warm blooded animals . it is regarded as a sensitive indicator for faecal contamination 大肠杆菌则可在人类和温血动物的肠脏找到，是检测水质有否被粪便污染的敏感指标。
2.
This is a product of the metabolism of warm blooded animals . it is an important indicator of contamination of water source . the ammonia nitrogen in the water is not toxic or poisonous to humans 人畜等温体动物代谢之产物，为水源是否受到污染的重要指标，水中存在氨氮对人体几不具毒性，主要为味觉之困扰。
