A global loss of biodiversity has accelerated since the age of industrialization, approaching 1,000 times the normal rate for extinctions on the planet. The acceleration of extinctions is almost certain to continue, due primarily to habitat loss, pollution, over-harvesting, and the introduction of invasive species. Biodiversity provides innumerable services to humanity, including air and water quality, pollination, and agricultural productivity, Currently between 10 and 30 percent of land animals are threatened with extinction, and 75 percent of fisheries are over-exploited. Loss of biodiversity, and the complex ecological systems it supports, is irretrievable. The human population sits at the pinnacle of a food and sustenance chain that is breaking at ever faster rates of speed.
The world economy rests on the back of the environment. Over-harvesting of natural resources leads to scarcity. Pollution of air and water leads to deteriorating public health and requires additional expenditures to treat it. Pollution also renders land and water unsuitable for economic activity, whether agriculture, fisheries or tourism. Environmental degradation by definition means a loss of common resources, including forests, rivers and streams, topsoil and local biodiversity. When common resources are lost due to over-exploitation or pollution, human communities lose the future opportunity for economic use.
According to the World Health Organization, one-quarter of global disease, and one-third of childhood disease, is a result of environmental hazards. Environmental toxins caused by pollution are a major culprit. Water-born illnesses such as diarrhea afflict millions in developing countries, and are compounded by problems of food scarcity. Approximately one in eight people lacks access to safe water. Air pollution causes respiratory illness. Pollution also leads to increased rates of cancer throughout the developing and developed world.
Environmental catastrophes often occur due to neglect, whether through lack of adequate regulation and enforcement, or through willful violation of environmental standards. The BP Gulf oil spill was only the latest of many such catastrophes. The Chernobyl nuclear accident caused widespread human health problems and the evacuation of a large area in Ukraine. The Bhopal chemical disaster in India killed over 3500 people. Other environmental disasters include the pollution of the Niger delta in Nigeria, the Fukushima nuclear following the 2011 earthquake and tsunami and the environmental threat to the Great Barrier Reef in Australia.