Original sentence: It specifically refers to systematic, high-altitude dumping of unknown substances for undisclosed purposes, resulting in the appearance of these unusual contrails.The Chemtrail conspiracy theory claims that some trails left behind jet aircraft are different in appearance and quality from those of normal contrails, may be composed of harmful chemicals, and that these different contrails are being deliberately produced, and covered up by the government.The belief is that a chemical and/or biological agent of some sort is being released.These unusual trails are referred to as "chemtrails" (a portmanteau of "chemical trails")
Edited sentence: It specifically refers to systematic, high-altitude dumping of unknown substances for undisclosed purposes, resulting in the appearance of unusual patterns not explained by normal contrail phenomenon.Numerous citizens in various countries have asserted that chemical and/or biological agent of some sort are being released, and such chemtrails have been associated with a number of medical conditions, including inter alia respiratory, skin, and memory problems.The term Chemtrail conspiracy theory is an attempt to minimize and belittle claims that some trails left behind jet aircraft are different in appearance and quality from those of normal contrails, are possibly composed of harmful chemicals, and deflects the fact that despite repeated attempts of citizens around the world to have such flights and chemicals addressed and explained, governments have consistently refused to address their concerns.These unusual trails, which are often left in complex, gridlike patterns, are referred to as "chemtrails" (a portmanteau of "chemical trails")