World population set to reach 7bn
The world's population is set to reach seven billion by the end of the month.
The United Nations Population Fund is predicting that the milestone will be hit on October 31.
It also expects the world population to reach eight billion by 2025 and 10 billion by 2083.
Population Council vice-president John Bongaarts said the population surge is having a devastating impact on the environment.
"Rapid population growth is leading to fresh-water shortages and ground-water depletion, particularly in densely populated countries in the developing world," Mr Bongaarts said in a podcast for Woodrow Wilson Centre's New Security Beat blog.
"Steadily increasing population also contributes to pollution of both local and global environments."
The poorest regions of the world are set to be worst hit.
"Countries with limited natural resources and extremely rapid population growth, most of them in sub-Saharan Africa, will fare the worst," Mr Bongaarts said.
"And despite the Aids epidemic, sub-Saharan Africa is expected to add more than a billion to its current population in the next half century."