Dust allows nasty chemicals to bind to it. Adults, but more particularly children, are at risk of dangerous chemical exposure if dust in the home or workplace becomes contaminated with heavy metals. There are many ways this happens.
There is a delicate balance between sufficient nutrient intake and toxic chemical load. The detoxification system within humans has innate learning capabilities comparable to our immune system and our brain. At this point in history (2017), our exposure to unfettered horrendous chemicals increases daily. Like many other areas in life, imbalance leads to illness and anxiety.