Pakistan 's sea shores are amongst the most polluted in the world, says a recent United Nations study. Other members of the Dirty Seas Club are Bangladesh , Indonesia , Mala-ysia and Nigeria .

Untreated sewage pouring into their seas pollutes their water and coastlines hurting the health and welfare of people and animals that inhabit their coasts.

UN report covers seas and oceans worldwide. Apart from the growing problem of urban sewage, oceans also suffer from rising levels of run-offs from agricultural land. It triggers toxic algal blooms that deprive water of oxygen.

This results in destruction of coastal ecosystems (mangroves) and a rising tide of ocean litter, says the report titled 'State of the Marine Environment'. The study was done by U.N. Environment Program.

According to the study, an estimated 80 per cent of marine pollution originates from the land. This could rise significantly by 2050, because coastal populations are likely to double about 40 years and combating the pollution is not expected to accelerate.

In 20th century the world had been thinking of converting oceans into sewage treatment plants, said an expert. But the seas have been declining to oblige, he added.

However, there is some good news: oil pollution is decreasing.