Volatile Organic Compounds (VOCs) are potentially dangerous compounds created by both human industry and natural processes that vaporize under normal atmospheric conditions. VOC levels are much higher in indoor environments as they can be emitted by many manufactured products such as carpet, paint, and cleaning supplies. Outdoor sources can include landfills, industry, and hydrocarbon emissions. Prolonged human exposure to VOCs have been known to cause respiratory problems, cancer, and neurological damage. Environmental damage can include air, water, and soil pollution.