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Pollution

The air pollution in Cairo is a matter of serious concern. Greater Cairo's volatile aromatic hydrocarbon levels are higher than many other similar cities. Air quality measurements in Cairo have also been recording dangerous levels of lead, carbon dioxide, sulphur dioxide, and suspended particulate matter concentrations due to decades of unregulated vehicle emissions, urban industrial operations, and chaff and trash burning. There are over 4,500,000 cars on the streets of Cairo, 60% of which are over 10 years old, and therefore lack modern emission cutting features. Cairo has a very poor dispersion factor because of its lack of rain and its layout of tall buildings and narrow streets, which create a bowl effect.

In recent years, a black cloud (as Egyptians refer to it) of smog has appeared over Cairo every autumn due to temperature inversion. Smog causes serious respiratory diseases and eye irritations for the city's citizens. Tourists who are not familiar with such high levels of pollution must take extra care.

Cairo also has many unregistered lead and copper smelters which heavily pollute the city. The results of this has been a permanent haze over the city with particulate matter in the air reaching over three times normal levels. It is estimated that 10,000 to 25,000 people a year in Cairo die due to air pollution-related diseases. Lead has been shown to cause harm to the central nervous system and neurotoxicity particularly in children. In 1995, the first environmental acts were introduced and the situation has seen some improvement with 36 air monitoring stations and emissions tests on cars. Twenty thousand buses have also been commissioned to the city to improve congestion levels, which are very high.

The city also suffers from a high level of land pollution. Cairo produces 10,000 tons of waste material each day, 4,000 tons of which is not collected or managed. This is a huge health hazard, and the Egyptian Government is looking for ways to combat this. The Cairo Cleaning and Beautification Agency was founded to collect and recycle the waste; they work with the Zabbaleen community that has been collecting and recycling Cairo's waste since the turn of the 20th century and live in an area known locally as Manshiyat naser. Both are working together to pick up as much waste as possible within the city limits, though it remains a pressing problem.

Water pollution is also a serious problem in the city as the sewer system tends to fail and overflow. On occasion, sewage has escaped onto the streets to create a health hazard. This problem is hoped to be solved by a new sewer system funded by the European Union, which could cope with the demand of the city. The dangerously high levels of mercury in the city's water system has global health officials concerned over related health risks.