lower Periyar as "a cesspool of toxins, which have alarming levels of deadly poisons like DDT, endosulfan, hexa and trivalent chromium, lead, cyanide, BHC". Several studies have pointed out that the riverbed has deposits of heavy metals like lead, cadmium, mercury, chromium, nickel, cobalt and zinc and the ecosystem of the river has many dead zones. Some of the major recommendations are ensuring zero effluent discharge from the industrial units in the Eloor-Edayar stretch and zero emission from companies. Pollution of the river and surrounding wetlands has almost wiped out traditional occupations, including fishing and farming. Illegal sand mining Illegal sand mining from the Periyar is another major environmental issue. Studies have pointed out that the quantity of sand being mined from the Periyar is at least 30 times the actual quantity that can be taken out without causing damage to the river’s environmental system. In the Periyar river basin, land sand mining is widespread in the plateau region in the highlands. Mining of sands from these areas impose severe environmental problems to the river basin environment. Environmental protection efforts Efforts have been made to prevent soil erosion on the banks of river periyar at Aluva Sivarathri manappuram (sand bank) through afforestation programs headed by renowned environmentalist, Prof. S. Sitaraman, since 1992. The Aluva Environmental Protection Forum started by Sitaraman and others have played a pivotal role in the prevention of illegal sand mining and water pollution in the lower reaches of the river. Dispute The control and safety of the Mullaperiyar dam on the river and the validity and fairness of the corresponding lease agreement have been points of dispute between Kerala and Tamil Nadu states. Intertwined with this, there is a dispute as to whether the Periyar should be classified as an inter-state river or not. Kerala states that the Periyar is an intrastate river since no part of it flows through Tamil Nadu. The river originates in Kerala, flows entirely through Kerala and joins the Arabian Sea in the Kerala. Although these facts have been admitted by Tamil Nadu, it counters that the Periyar should be considered an inter-state river since a part of the catchment of the river lies in Tamil Nadu. It has also cited a 1950 report signed by the then Kerala state irrigation minister V R Krishna Iyer recording that Periyar is an inter-state river since some of its drainage area lay in