Environmental responsibility for Singapore is vested in the Ministry of the Environment and its Anti-Pollution Unit. Air quality is protected by the Clean Air Act, as adopted in 1971 and amended in 1975 and 1980, and by the Clean Air (Standards) Regulations of 1975. Regulations limiting the lead content of gasoline were imposed in 1981, and emissions standards for motor vehicles were tightened in 1986. Air pollution from transportation vehicles is a problem in the nation's growing urban areas. In 1992, Singapore was among 50 nations with the world's highest levels of industrial carbon dioxide emissions, which totaled 49.8 million metric tons, a per capita level of 17.99 metric tons. In 1996, the total rose to 65.8 million metric tons.
Water quality is regulated through the Water Pollution Control and Drainage Act of 1975 and the Trade Effluent Regulations of 1976. Singapore does not have enough water to support the needs of its people. In total, the nation about has 0.1 cubic miles of water. Four percent is used for farming and 51% for industrial purposes. Pollution from the nation's oil industry is also a significant problem, and its cities produce about 0.9 million tons of solid waste per year. Waste water is treated and recycled to conserve water supplies. Altogether, Singapore has lost 20 to 30% of its original mangrove area.
In 2001, two plant species, six mammal species, and nine bird species were considered to be in danger of extinction. Endangered species in Singapore include the Ridley's leaf-nosed bat, Chinese egret, yellow-crested cockatoo, batagur, tigers, and the Singapore roundleaf horseshoe bat.