Lead: heavy metal is also an atmospheric pollutant
Presence of lead in the air is harmful to health
Lead (Pb) is a heavy metal commonly found in the earth's crust in its solid form, but in some processes it ends up becoming an atmospheric pollutant, classified as dangerous due to its toxicological potential. Despite being toxic as an atmospheric pollutant, the metal does not fit into the group of substances that serve as indicators of air quality and therefore does not appear in the indices published by CETESB.
According to a scientific source, hazardous pollutants such as lead, benzene, toluene, xylene and polycyclic organic materials (chromium, cadmium) are not frequent in the atmosphere and their occurrence is more related to the proximity of areas where there are production processes that emit these substances.
Lead is released into the environment through industrial processes, mainly in the chemical, automotive, construction and mining activities. Leaded industrial gases are transported for a few kilometers and, when sedimented, can contaminate air, soil and water.
In urban centers, pollution by this heavy metal used to happen on account of vehicles running on gasoline that contained lead. The potential for propagation of the substance in gasoline was a radius of up to 100 meters away, making it necessary to introduce unleaded gasoline, which significantly reduced the levels of the pollutant in the atmosphere.
The incorrect disposal of electronic devices is one of the ways in which the metal is spread more by nature. The most common items that contain lead are CRT monitors and fluorescent lights.
Effects
Lead contamination in the environment harms nature and human beings, as we are at the top of the chain and, when we eat contaminated food, lead can accumulate in our body.
A study shows that lead particles are inhaled as particulate material and are deposited in the lungs, although they can also be acquired through the digestive tract. From then on, when they are absorbed, the cumulative effect causes these gradual deposits to also accumulate in teeth and bones and trigger diseases.
By affecting the blood, lead can cause anemia, red blood cell degeneration, and interfere with hemoglobin production. In the nervous system, neuritis is observed in adults and encephalopathies in children.
How to avoid
State Decree No. 59113 of 23/04/2013 establishes values for lead emission, but its monitoring takes place only in specific areas, at the discretion of the Technology and Basic Sanitation Company of the State of São Paulo (Cetesb), being the final standard , for annual arithmetic means, in the state of São Paulo, of 0.5 μg/m³ (micrograms per cubic meter). Improving monitoring would be one of the ways to control emissions, in addition to stricter legislation for industries, with gas depollution measures reaching lower final standard values.
One of the measures already adopted was the introduction of unleaded gasoline, but aviation gasoline still has the metal in its composition. This affects the health of people who live near airports, especially children (learn more here). But there are already aircraft fuel alternatives that reduce the amount of aviation gasoline used or even replace it entirely.
To see more tips on how to avoid contact with metal and products that contain lead and are present in our daily lives, check out the article "Lead: applications, risks and prevention".
