The department of chemistry at the college of education for pure and applied sciences (Ibn Al-Haytham) has sponsored a training course entitled (Negative effects of chemicals on human health) in which the professors at first defined the negative impact as an abnormal, unwanted or harmful change resulting from exposure to toxic chemicals. These effects may appear either in the form of skin rashes or allergic reactions in the respiratory or digestive system and they may sometimes lead to blindness or cancer.
The participants then talked about the chemicals that have become an integral part of our lives as they support many of our activities, prevent or control many diseases, increase the agricultural productivity, so we can say that their benefits are countless, but on the other hand, they may pose a threat to our health and damage our environment. Humans are exposed to a range of chemicals, whether in the form of medical, industrial or environmental chemicals, and even naturally occurring substances. All substances have the ability to cause harmful effects which are referred to as adverse or side effects.