What is pollution?
Any substance that has the potential to cause harm to people, animals, plants, or things is considered to be an air pollutant. Pollutants in the air may be either a direct or indirect threat to human health, as they may increase the risk of death or serious disease.
Pollution is mainly classified into the following categories.
1. Gaseous pollutants
Ozone and nitrogen dioxide are the two most harmful gases polluting our cities and regions today. Chemical interactions between nitrogen oxides (NOx) and volatile organic compounds (VOC) in the presence of sunlight produce photochemical smog, in which these pollutants play a significant role.
2. Persistent organic pollutants
The group of chemicals known as “persistence organic pollutants” is extremely dangerous. They stay around for a long time, and their impact grows as they go higher and higher in the food chain (bio-magnification). Pesticides, dioxins, furans, and PCBs are all examples of such chemicals.
3. Heavy metals
Lead, mercury, cadmium, silver, nickel, vanadium, chromium, and manganese are all examples of heavy metals. They are elements found in the crust of the earth and hence cannot be degraded or eliminated, can be carried by air, and can contaminate our drinking water and food. Furthermore, they are introduced into the environment by many other routes, including combustion, wastewater discharge, and industrial facilities.
4. Particulate matter
Particulate matter (PM) refers to a broad category of air pollutants that includes a wide range of different types of microscopic and non-microscopic particles that are suspended in the air we breathe.
Effects of air pollutants on different organs and systems
a. Effect of pollution on the respiratory system
Numerous studies have shown that high levels of any sort of air pollution can have negative effects on the respiratory system. However, long-term exposure to lower pollutant concentrations also results in similar effects. Sulfur dioxide, nitrogen oxides, and some heavy metals like arsenic, nickel, or vanadium can cause nasal and throat irritation, bronchoconstriction, and dyspnea, especially in asthmatic persons. Additionally, ozone and particulate matter that enters the alveolar epithelium cause lung inflammation. Pollutants can exacerbate the symptoms of people with preexisting lung lesions or lung diseases by triggering an inflammatory response. In addition, breathing in nitrogen oxides and other air pollutants makes you more susceptible to respiratory diseases.
b. Effect of pollution on the cardiovascular system and pollution
Blood artery obstruction (cardiac) can cause angina or even myocardial infarction (MI) due to air pollution’s effects on the lungs and blood coagulation. Heavy metal contamination (particularly mercury, nickel, and arsenic) has been linked to symptoms like tachycardia, high blood pressure, and anemia due to an inhibitory influence on hematopoiesis. Lastly, dioxin exposure has been associated in epidemiological studies with an increase in ischemic heart disease-related mortality, and heavy metal exposure has been demonstrated to increase triglyceride levels
c. Nervous system and pollution
Dioxins and heavy metals like lead, mercury, and arsenic have devastating effects on the nervous system. Arsenic, lead, and mercury exposure have all been linked to neurotoxicity and subsequent neuropathies, with symptoms including memory loss, sleeplessness, rage, exhaustion, hand tremors, blurred vision, and slurred speech. Particularly crucial for memory processes are the dopamine system, the glutamate system, and the N-methyl-D-aspartate (NMDA) receptor complex, all of which are damaged by lead exposure. In addition, mercury contributes to the development of some forms of cancer in the nervous system. Children that were exposed to dioxins had slower nerve conduction velocities and poorer cognitive development.
d. Effect of pollution on the urinary system
Injuries to the kidneys, such as those caused by heavy metals, can have an abnormality in tubular function manifested by an increase in the excretion of lower-weight proteins, which leads to a decline in GFR, or the glomerular filtration rate (GFR). Further, they amplify the threat of kidney stone development and kidney cancer.
e. Digestive system
Dioxins increase the levels of certain enzymes in the liver, suggesting that they induce cell damage in the liver and may also contribute to the development of digestive and liver cancers.
f. Exposure during pregnancy
Fetal development can be negatively impacted by exposure to air pollution, which is something that should be noted. Spontaneous abortions and stunted fetal growth (preterm delivery, low birth weight) are more likely when a pregnant woman is exposed to heavy metals, especially lead. In addition to producing significant impairment in newborns’ motor and cognitive capacities, there is evidence to show that parental lead exposure is responsible for congenital abnormalities and lesions of the developing nervous system. Dioxins were also shown to cross the placental barrier and reach the developing baby. They have endocrine-disrupting effects, altering CNS development and growth.
Natural protection against pollution
Drug or xenobiotic metabolizing enzymes (DMEs or XMEs) serve a major role in the biotransformation, metabolism, and/or detoxification of xenobiotics or foreign chemicals, including many types of pollutants, to protect the human body from potential harmful insults from the environment. Cytochrome P450 (P450 or CYP), epoxide hydrolase, glutathione transferase, UDP-glucuronosyltransferase, sulfotransferase, NAD(P)H quinone oxidoreductase 1, and Aldo-keto reductase are all examples of xenobiotic metabolizing enzymes (XMEs).
There are a variety of dietary items that aid in the body’s natural chelation processes and are advantageous to health in general. Antioxidants, herbs, minerals, vital amino acids, various detoxifying or protecting agents, and fiber all have natural chelating capabilities and may aid in the detoxification process. Antioxidant enzymes (like peroxidase) and nonenzymatic substances (like glutathione, or food-derived like vitamin E or polyphenols) contribute to the antioxidant defense system in the body, along with other enzymes involved in damage removal and repair.
The important takeaway is that in light of people’s rising exposure to a wide range of contaminants, diets high in plant-based foods can help shield against or mitigate the ill effects on many body systems. Several epidemiological studies demonstrating the health benefits of Mediterranean diet support this view.