Basu P K, Avaria M, Hasany S M
Can J Ophthalmol. 1982 Apr;17(2):74-8.
The normal eyes of 6 men and 21 rabbits were exposed to samples of lake water, one eye to a sample of pH 4.6 and the other to a sample of pH 6.3. The men's eyes were exposed for 5 minutes on four occasions a week apart, whereas the rabbits' eyes were exposed for 15 minutes either on one occasion or once a day for 7 days. In the humans neither sample of water produced symptoms or signs of an adverse effect on the external eye tissues, apart from brief conjunctival congestion after every exposure. In the rabbits the two samples did not appear, in general, to have different effects on the ocular tissues, as judged from the osmolarity and cell count of the tears, conjunctival congestion, corneal staining with fluorescein, corneal permeability and histologic features of the cornea. In a few instances differences were observed, but their pathological significance was not apparent. These data suggest that lake water of a pH as low as 4.6 may not harm healthy eyes, however, larger and broader studies are essential.
6名男性和21只兔子的正常眼睛被暴露于湖水样本中，一只眼睛暴露于pH值为4.6的样本，另一只眼睛暴露于pH值为6.3的样本。男性的眼睛每周暴露4次，每次5分钟，而兔子的眼睛要么暴露15分钟一次，要么每天暴露一次，持续7天。在人类中，除了每次暴露后出现短暂的结膜充血外，两种水样均未对眼外部组织产生不良反应的症状或体征。在兔子中，从眼泪的渗透压和细胞计数、结膜充血、荧光素角膜染色、角膜通透性和角膜组织学特征判断，这两种水样总体上对眼组织没有不同影响。在少数情况下观察到了差异，但其病理意义并不明显。这些数据表明，pH值低至4.6的湖水可能不会伤害健康的眼睛，然而，更大范围和更广泛的研究至关重要。
