Manufacturers bank on our beliefs

We often believe that legally marketed household cleaners are safe to human health and neurological function. Manufacturers bank on that. They know that people believe that because it is in stores for sale then they (the manufacturer) have met standards set by the government to sell this product. That is not true - well, not completely. Because very few hazardous chemicals are tested, very few have legislation created for manufacturers to meet.  Why is it that Asthma has increased by 400-600% (depending on who is stating it) since the early 90's? Why is it that when people change their household cleaners to more natural cleaners their asthma is greatly reduced, if not gone altogether? Why are these not the stories that make it to headlines more often?