Types of Environmental Pollutants and Their Health Impacts
Classification of Pollutants
Pollutants can be classified according to their specific characteristics:
- Physical agents
- Chemical agents
- Biological agents
- Psychological pollutants
Physical Pollutants
Physical contaminants alter the environment’s quality by their mere presence. They are characterized by an energy exchange between a person and the environment at a rate the body cannot withstand. Radioactivity (natural or artificial) is a significant example of physical pollution related to environmental geology. Other examples include noise, bright light, ionizing radiation, vibration, temperature, and pressure.
Diseases Caused by Thermal Agents
Diseases caused by high temperatures: When body temperature rises due to working in a hot environment, the body increases blood circulation to transport heat to the skin’s surface and lose it by radiation (accelerated heart rate with resulting heart fatigue). It also increases sweating to lower the temperature by evaporation, which must be compensated by ingesting water and salt, as sweat contains 5% sodium chloride. Physical activity and performance decrease.
Diseases caused by cold temperatures: When body temperature drops, blood circulation reduces to minimize heat loss, and vasoconstriction occurs in the skin to reduce the radiating surface. If the body temperature falls below 34°C, the worker may become semi-conscious.
Diseases Caused by Mechanical Vibration
These occur mainly in groups of workers such as masons and miners who are subject to vibrations that can sometimes affect the entire body, as these are transmitted through the skeleton. Among the most significant local diseases are:
- Dead finger, which may appear after two years of work and only in the affected area.
- Kienbock disease or lunate necrosis at the wrist, although rare, may cause hand impotence with carpal pain.
- Muscle, nerve, or osteoarticular injuries.
- Loriga’s disease, typical of workers who use compressed air tools.
Radiation
Natural background radiation: Exposure to such radiation can lead to local skin effects depending on dose, cataracts, sterility, radio-epidermis, and temporary hair loss.
Artificial radiation: This comes from environmental pollution by radioactive wastes, sedimentation of radioactive dust or particles produced by nuclear devices, exposure of workers (radiographers, uranium miners, nuclear plant personnel, etc.), medical uses of radiation for diagnosis and treatment, or the use of certain radiation-emitting devices. Exposure to this radiation can lead to local skin effects depending on dose, blood disorders, plastic anemia, leukemia, bone necrosis, and cancer.
Diseases Caused by Noise
Intense noise can affect the human body in various ways, either by reflex action or impact on the psyche. The effects of loud noise on the human body include:
- Action on the circulatory system (increased blood pressure and heart activity, peripheral vasoconstriction)
- Action on the metabolism (acceleration)
- Muscular action (increased tension)
- Action on the digestive system (inhibition of organs)
When noise acts on the ear, depending on its intensity and duration, it can cause irreversible sound trauma to the organ of Corti. This can occur either through slow injury from intense noise or acute severe accidents that may lead to deformation or injury of the basilar membrane.
Factors influencing the development of deafness caused by noise exposure:
- Noise intensity
- Frequency
- Exposure time
- Individual susceptibility
Chemical Pollutants
Chemical pollutants are composed of organic or inorganic inert material, either natural or synthetic (gases, fumes, dust, mist). They alter the chemical makeup of the environment’s components, potentially affecting living things. Examples include toxic gases, heavy metals, halogens, organic and inorganic acids, strong alkaline compounds, pesticides, and cyanides.
Classification of chemical contaminants most studied by Occupational Health:
Solids
- Dust: (silica, asbestos, cotton, linen, wood, inert materials, metal oxides, talc, metals, grains, etc.) Airborne particulate matter from handling, grinding, polishing, etc., of organic or inorganic solids. Its size is highly variable, and its shape is irregular.
- Smoke: (coal, asphalt, oil) Airborne particulate matter, carbon, and soot from incomplete combustion.
- Metal Fumes: (chromium, iron, nickel, titanium, silver, lead, magnesium, etc.) Airborne particulate matter from gaseous condensation caused by the sublimation or melting of metals.
Liquids
- Mist: (hydrocyanic acid, hydrochloric acid, sulfuric acid, chromic acid, mineral oil, etc.) Air dispersion of liquid droplets, usually visible to the naked eye, caused by condensation of gaseous or liquid dispersion by spray, boiling, or gurgling.
- Haze: Air suspension of liquid droplets visible to the eye, produced by condensation from the gaseous state.
- Smog: Derived from smoke and haze, applicable to atmospheric contamination due to aerosols caused by a combination of natural and industrial causes.
Gases
- Gas: (carbon monoxide, carbon dioxide, chlorine, ozone, etc.) Substances in a gaseous state under normal pressure and temperature conditions.
- Vapor: (aromatic hydrocarbons, cyclic and aliphatic ketones, alcohols, etc.) Substances that are solid or liquid under normal pressure and temperature conditions.
Some diseases caused by chemical agents can be classified into diseases caused by:
- Dust
- Organic compounds
- Inorganic compounds
Diseases Caused by Dust
These are illnesses caused by contaminants in powder form, labeled as nosoconiosis, and named according to the affected organ:
- Pneumoconiosis affects the lungs.
- Dermaconiosis affects the skin.
- Rhinoconiosis affects the nose.
- Osteoconiosis affects the bones.
- Ophthalmoconiosis affects the eyes.
Biological Pollutants
Biological contaminants are mainly microorganisms that can degrade the quality of air, water, soil, and food. They consist of live agents that pollute the environment and can lead to infectious or parasitic diseases, such as microbes, insects, bacteria, and viruses.
Classification of biological contaminants most studied by Occupational Health:
- Viruses
- Fungi
- Bacteria
- Worms