The correct answer is March 1989 -Switzerland. Explanation & Key Takeaways: Basel Convention • The Basel Convention on the control of the transboundary movement of hazardous wastes and their disposal was adopted on 22nd March 1989 in Switzerland. • This came into being in furtherance of the public outcry over the disposal of hazardous wastes to Africa from other developed countries. • Some of its provisions include: The regulatory system of the Basel convention is based on the system of 'Prior informed consent' which requires the prospective exporter states to notify the importer and transit state regarding the detailed information on the intended movement. • Other provisions include: • Requiring states to observe environmentally sound principles of waste management • Provides for cooperation between parties on issues relevant to the implementation of the convention and provides technical assistance to developing countries. • The secretariat acts as a clearinghouse for cooperation. • It provides for sub-regional centers and assists in technological transfers for the management of hazardous wastes and minimization of their generation to cater to the specific needs of different regions and sub-regions.