Yalda Khalatbari - PhD Student of Environmental Law – Islamic Azad University- Science & Research Branch of Tehran
David Hermidas Bavand - Visiting Professor of Islamic Azad University, Science and Research Branch of Tehran
Ali Zare - Assistant professor, Department of private law, college of law and political science, Tehran science andresearch branch, Islamic Azad University, Tehran, Iran
Seyed Abbas Poorhashemi - Assistant Professor of Tehran University of Science and Research (IAU) and Member of the Center forthe Study of International Law and Globalization of University of Québec in Montréal, Canada

Due to the environmental degradation, pollution and other environmental damages caused by theuncontrolled economic development and population growth and other human activities have the multipleimpact and harmful effects on the environment (Larsson 2009). In fact, the environment doesn’t have anyborder, so any damage to the environment in one area or country cause damage to other countries(Poorhashemi, 2013). Some scientists and researchers predict the disappearance of the environmentalquality due to the irreversible damage that are and will continue to be done to the global environment.Environmental damage is a rather complex concept which to date has not yet found a unanimousdefinition universally accepted. Taking into account that the main purpose of international environmentallaw is the protection of the global environment, for this reason, unifying the concept of environmentaldamage is crucial to determine who is responsible for environmental degradation. The importance of thedefinition of environmental damage is based on States responsibility and liability to prevent, reduce andcompensate for environmental damage, accordingly, the unique definition of environmental damage hasan active role to play for states in environmental protection (Mitchel 2009). Basically, responsibility andliability treaties are not a panacea for pollution or environmental damage or other forms of transboundaryenvironmental damage and harm, and skeptics rightly question whether they have had much impact onindustry or contribute to improving standards (Brunnée 2004). In addition, the Report of the Secretary-General of the United Nations Conference on Sustainable Development on 22 December 2010 affirm thatthe sates have responsibility to utilise the natural resources in the manner which avoid the loss of land orenvironmental benefits or for environmental damages created by projects. (Report of the Secretary-General UN 2010)