About 2.85 billion people, or 46% of the worlds population in 2002, lacked access to basic sanitation, with almost one billion without basic sanitation in East Asia and South Asia and almost half a billion people in sub-Saharan Africa, it added.
The data released by the world body yesterday in its Little Green Data Book (LGDB) showed very little progress in the last 10 years, and experts said if the current trends continued, the developing world would not be able to achieve the UN millennium development goal of reducing by half the number of people without access to basic sanitation by 2015.
More than 50 countries in the developing world are off-track, and urgent action is needed to reverse this trend, the UN said, estimating that meeting the water supply and sanitation target would require doubling annual investment from $15 to $30 billion dollars a year.
Most of the increase is required for sanitation. However, increasing efficiency, quality and sustainability would require significant policy and institutional reform as well.
Wood fuel is still the primary source of energy for approximately two billion people. Indoor smoke from burning solid biomass is associated with respiratory problems. Most of the victims are infants, children, and women from poor rural families. Acute respiratory infections in children and chronic obstructive pulmonary disease in women is common in poor countries, says LGDB, released at the 13th session of the UN commission on sustainable development.
Poor countries, it said, faced the highest health risks caused by environmental factors such as use of biomass fuels and lack of access to clean water and sanitation, in addition to increased population pressures in urban areas.
LGDB tries to bring into focus the issues which need to tackled if better health for the poor is to be achieved.
In developing countries with high mortality rates, such as Cambodia, Burundi and Mozambique, indoor air pollution is the fourth leading cause of illness and death. Indoor smoke accounts for 3.6% of the burden of disease in developing countries with high mortality, following the lack of water supply and sanitation which accounted for 5.5% of death and illness.
"Environmental factors are often the invisible killers of the poor," said Warren Evans, World Bank environment director. "Reducing environmental risks will require new investments and significant policy and institutional reforms. Timely, accurate data are key to making decisions on environmental health.