Noise pollution
From blaring car horns to wedding parties, rising noise pollution in the 24-hour metropolis of Cairo has reached alarming levels, leading to health problems. Living in the city centre, where noise levels reach an average of 90 decibels (dB) and never drop below 70 dB, is like spending all day inside a factory, a 2007 study by the Egyptian National Research Centre (NRC) said "What's striking about Cairo is that noise levels on different streets at different times of day are well over limits set by the environmental protection agency (EPA)". Noise pollution can contribute to many health problems.