ABSTRACT
Biological contaminants refer to environmental contamination and food source with living microorganisms such as bacteria, molds, viruses, and fungi, in addition to mites, house dust, and pollen. Temperature, relative humidity, movement of air, and sources of nutrients have influenced the presence and spread of biological contaminants. Numerous living microorganisms can grow independently on each other, such as bacteria and fungi. Viruses (a small obligate parasite) depend on other living organisms for their development and for performing vital functions. Indoor air can contaminate with biological contaminants by a different status, including living, dead, or debris of the dead microorganisms which were transported through ventilation systems, when the microorganism components dissolve in water. They become aerosolized when the contaminants are physically disturbed, like in renovation or construction, and when the contaminants discharge harmful gases into the indoor environment. Most studies conducted in recent years agree that air pollution rates are increasing, bringing more risks to human health, as pollution is related to the risk of heart and lung disease and its effect on children, especially infants and newborns. Also, environmental pollution may have become the most dangerous disaster faced by humans, because it means environment retrogradation in which humans lives as a result of an imbalance within the compatibility of the constituent elements and loses its ability to carry out its natural role in self-removal of contaminants by the natural factors noticeable within air, land, and water. In some cases, many common infections can spread through airborne contaminated microorganisms such as Mycobacterium tuberculosis, measles virus (MV), influenza virus, Morbillivirus, chickenpox virus, norovirus, enterovirus, less commonly coronavirus, adenovirus, and respiratory syncytial virus (RSV). When an infected person coughs, talks, sneezes, has throat secretions, and releases nasal into the air, the airborne infection can spread. Bacteria or viruses spread out noticeably in the air or ground and transport to other persons or surfaces. This review provides the conception of biological contaminants and their properties, nature of the indoor environment, and adverse health effects associated with biological contaminants. © 2022 Medical Journal of Babylon. All rights reserved.