Air Pollution and Kidney Disease: An Overview

Introduction

Kidney disease is an emerging global phenomenon with high incidence and mortality rates that affects the entire world, which includes irreversible damage and reduced ability for kidney regeneration. Recent studies have shown that there may be a direct correlation between air pollution exposure and the risk of chronic kidney disease. Evidence suggests that Inhaled airborne particles can induce glomerulosclerosis, intra-glomerular hypertension, or vascular damage through complicated interactions. So, it is necessary to thoroughly understand the causes, effects, and treatment options to diagnose and manage the disease effectively.

What Are the Air Pollutants that Cause Kidney Disease?

Heavy metals are the common environmental contaminants that cause kidney diseases. These air pollutants specifically include uranium and arsenic (As), but also Cadmium(Cd), Lead(Pb), Mercury(Hg), Uranium, and Particulate matter.

• Arsenic: Hypertension and kidney damage have been related to contamination of drinking water with arsenic. This may result in acute damage to the kidneys, leading to the formation of acute tubular necrosis, nephrocalcinosis, hypercalciuria, albuminuria, and necrosis of the renal papillae. It can also cause tubulointerstitial nephritis.

• Cadmium: It is found to be the leading cause of damage to kidneys in smokers as well as nonsmokers. It is generally found in high concentrations of tobacco, and for nonsmokers, it is exposed through contamination of food by cadmium. It causes tubular damage and loss of glomerular filtration rate.

• Lead: Lead is considered one of the dangerous substances that can injure the kidneys. On exposure, it tends to build up in the bones and kidneys. Lead in the kidneys can result in oxidative stress, inflammation, and cell damage.

• Mercury: It is one of the most harmful substances that cause irreversible damage to kidneys. It mainly enters the bloodstream through inhalation and causes damage to intrinsic cell organelles, such as damage to mitochondria, disruption of endoplasmic reticulum leading to impaired protein synthesis, nuclear pyknosis (a sign of cell damage), impairment of nutrient absorption, and finally to cell death.

• Uranium: Uranium is a radioactive substance that causes toxic kidney reactions. On accidental exposure, it is absorbed into the bloodstream and carried by transferrin as a complex molecule. It gets dissociated as a uranyl ion, reacts with proximal tubules of the kidneys, and causes damage.

• Particulate Matter (PM): These are the small solid particles present in the air derived from the combustion of gasoline, coal, and other fuels that cause air pollution. These are of different dimensions and diameters. PM10 worsens the symptoms of albuminuria (increased albumin in the urine), and PM2.5 causes membranous nephropathy (a type of kidney disease).

How Do Air Pollutants Damage the Kidneys?

There are numerous ways that air pollution can harm the kidneys. The following are a few mechanisms that have been suggested:

• Oxidative Stress: Reactive oxygen species are the chemical substances that cause damage to the cells, produced by air pollution. It usually affects the mitochondria, which are considered powerhouses of the cell. It causes an imbalance in free radicals, leading to cell death.

• Inflammation: Air pollution can trigger inflammatory pathways that generate inflammatory mediators in the kidneys. These mediators cause sustainable harm to kidney cells.

• Direct Cell Injury: Air pollution can cause direct kidney cell damage. For instance, the circulation can carry PM2.5 particles into the kidneys, directly harming the proximal tubule cells and causing glomerulosclerosis (scarring and damage of glomeruli).

• Impaired Renal Blood Flow: Air pollutants can cause impaired blood flow in kidneys, accumulating waste products, promoting inflammation, and impaired kidney function.

• Altered Gene Expression: Air pollutants can cause altered gene expression, leading to kidney function failure. However, the exact mechanism is still unclear and requires further research to understand the procedure.

• Increased Risk in Metabolic Disorders: Air pollutants increase the risk of hypertension and diabetes, which indirectly affects the health of the kidney, leading to kidney failure.

How to Reduce the Kidney Damage Caused by Air Pollutants?

Reducing air pollutants is usually a multidisciplinary approach that includes individual approaches and policy recommendations. These are a few simple steps that one can take to prevent kidney damage caused by air pollutants.

Individual Approach:

• Avoid Outdoor Activity During High Air Pollution: Always be cautious of air quality forecasts and avoid going out during elevated air pollution levels.

• Decrease Indoor Air Pollution: Prevent indoor air pollution by installing HEPA filters that help to remove particulate matter from the air within buildings. Refrain from smoking indoors and use scented candles and air fresheners sparingly.

• Stay Hydrated: Drinking plenty of water helps to remove unwanted accumulated toxins from the body and promotes kidney function effectively.

• Eat a Balanced Diet: Eat a balanced diet full of foods high in antioxidants and anti-inflammatory properties to help protect the kidneys from the damaging effects of air pollution.

• Avoid Smoking or Drinking Alcohol: Smoking and alcohol are found to be risk factors in raising blood pressure, which indirectly harms kidney function.

• Maintain a Healthy Lifestyle: Stress reduction, regular exercise, and enough sleep can all improve kidney function overall and lessen the harmful effects caused by air pollution.

• Do Regular Kidney Tests: It is essential to get regular kidney tests if the individual has a history of diabetes and hypertension, which are considered risk factors for kidney disease.

Policy Recommendations:

• Impose Stronger Air Quality Regulations: To prevent increased air pollution levels, governments should impose stronger regulations on the quality of air and implement them more strictly.

• Encourage the Use of Renewable Energy Sources: Switching to solar and wind power, for example, can reduce emissions from power plants and other industrial sources of air pollution.

• Invest in the Infrastructure of Public Transportation: Public transit systems can help reduce traffic emissions and the resulting air pollution by encouraging people to leave their automobiles at home.

• Increase Public Awareness: People can be inspired to take action to safeguard their kidney health by learning about the health concerns posed by air pollution and by being encouraged to adopt preventive measures.

Conclusion

In conclusion, it is necessary to remember that kidney damage usually occurs on exposure to certain metals in large concentrations for prolonged periods. To safeguard the public's health, safety standards, and guidelines have been set by regulatory bodies and public health groups to reduce exposure to certain hazardous metals. It is critical to get medical help right away if one suspects kidney injury or believes they may have been exposed to nephrotoxic metals. Kidney disease caused by air pollutants can be avoided by reducing exposure to these metals, proper health checkups, and following appropriate safety precautions and regulatory controls.