Egypt is preparing to tackle the “black cloud” smog, Mariam Rizk writes for BBC. The smog, which comes from burning rice straw, spread rapidly and now it accounts for 42% of the country's air pollution, according to the Environment Ministry. The ministry is tackling it by striking an agreement with a local company to use rice straw in cement production as well as using the waste and recycling it into fertilizer and fodder. Other “creative” solutions are yet to be picked up, Rizk notes, citing an attempt by an Egyptian engineer to use the gases coming out of burning the rice straw “to produce biodiesel, fertilisers, vitamin B and hydropower.”