biogas plant which produces methane from anaerobic digestion of wastewater. additionally, shehata al-moqadis, head of the garbage collectors union, inked a memorandum of understanding on may 21 with an italian company to build a waste recycling plant. ‘the new project aims at running a waste-to-energy plant with a capacity of 600-1100 tons per day that can be used to generate electricity or to produce gas’” another scheme supported by the world bank group has involved removing up to 40,000 old taxis from the streets of cairo. these taxis were sometimes up to 40 years old and lacked the technology to prevent harmful greenhouse gasses from entering the atmosphere. to date, the scheme has reduced 310,000 tonnes of carbon from cairo's emissions output. the old taxis are scrapped and recycled, whilst new taxis are provided to taxi drivers. health and environmental impacts according to a study, life expectancy for egyptians decreases by 1.85 years due to the level of air pollution, one of the worst ranked in the world. breath life estimates there are 67,283 annual deaths from air pollution, with the leading cause being ischemic heart disease. the water in egypt has also been found to contain heavy metal contaminants which can be harmful to health. lower egypt releases the most waste into the nile, it being the most populous, industrial and agricultural country in the basin. rivers in the upper egypt area are thought to have reduced fish varieties, phytoplankton and microorganisms. sources of pollutants in the nile include, oil pollution, municipal wastewater, agricultural drainage and industrial wastewater, among others. overall, the water quality isn't at crisis levels, however. only in local settings the water has been found to contain coli and so unsafe for use in fisheries and irrigation. close to industrial discharges and cities the water is quite polluted, but more generally the river holds a high dilution factor. cairo also has significant noise pollution. it is ranked as the second noisiest city in the world, with an average of 90 decibels, which is the equivalent to continuously living inside a factory. people living in very noisy cities tend to lose their hearing ten to fifteen years sooner than those living in quieter cities. continuous noise can also cause stress and anxiety. additionally, the improper disposal of waste in waterways is causing contamination of egypt's water supply. additionally, every october and november, farmers burn their rice straw in the delta districts causing a thick black smoke cloud to descend over the city. this has a number of health impacts for residents and makes the air harmful to breath, whilst also eroding the precious historical monuments in the city.