Author: Ip Tsz Yan Natalie, BBA (Law) IV; HKU
The plaintiffs were residents of Ilo, Peru, and representatives of deceased Ilo residents. The defendant’s operations emitted large quantities of sulfur dioxide and very fine particles of heavy metals into the local air and water. Plaintiffs claimed that these emissions have caused their respiratory illnesses and that this "egregious and deadly" local pollution constitutes a customary international law offense because it violates the "right to life," "right to health," and right to "sustainable development."
The District Court noted that, in order to allege a violation of customary international law, "a plaintiff must demonstrate that a defendant's alleged conduct violated 'well-established, universally recognized norms of international law.'
The appeal was dismissed. The treaties, conventions or covenants relied on by plaintiffs do not support the existence of a customary international law rule against intranational pollution.
The principles are boundless and indeterminate. They express virtuous goals understandably expressed at a level of abstraction needed to secure the adherence of States that disagree on many of the particulars regarding how actually to achieve them. 
- ↑ http://openjurist.org/414/f3d/233/flores-v-southern-peru-copper-corporation- last accessed 7/8/10