Radiation exposure is increasingly relevant in medical, environmental, and occupational contexts, bringing both benefits and health risks. This review evaluates the health impacts of ionizing and non-ionizing radiation, highlighting short- and long- term effects on human tissue and genetic material. Additionally, this paper discusses mechanisms of radiation protection, focusing on regulatory limits, shielding techniques, and advancements in personal protective equipment. Comprehensive understanding of these effects and protection strategies is crucial to reducing radiation-related risks, especially in medical and industrial settings where exposure is frequent.

• Radiation health effects
• Ionizing radiation
• Non-ionizing radiation
• Radiation protection
• Radiation shielding
• DNA damage

Yadeta GF (2024) Review on the Health Effects of Radiation and Its Protection Mechanisms. J Radiol Radiat Ther 12(1): 1106

Radiation is energy transmitted through space in the form of waves or particles, and it is commonly categorized into ionizing and non-ionizing radiation based on its energy and ability to ionize atoms. Ionizing radiation, such as X-rays and gamma rays, has enough energy to remove tightly bound electrons from atoms, leading to molecular changes and DNA damage [1]. Non- ionizing radiation, including ultraviolet (UV), microwaves, and radiofrequency, lacks sufficient energy to cause ionization but can still pose health risks, especially with prolonged exposure [2].

With the increasing use of radiation in medicine, industry, and telecommunications, understanding the health risks and protective mechanisms is essential. Studies have shown that while radiation can be beneficial in medical treatments such as cancer therapy, exposure to high doses or prolonged low-level exposure can result in adverse effects, including cancer, genetic mutations, and other health issues [3]. This review aims to explore the spectrum of radiation health effects and examine current and emerging methods of radiation protection.

Ionizing Radiation

Ionizing radiation has significant biological effects due to its high energy, which can cause cellular and molecular damage.

A. Acute Effects

Acute exposure to high doses of ionizing radiation can lead to immediate health effects, known as acute radiation syndrome (ARS), characterized by nausea, fatigue, skin burns, and, in severe cases, death [4]. ARS is commonly observed in radiation accidents or unshielded exposure to large doses of radiation.

B. Chronic Effects

Long-term exposure to ionizing radiation, even at low doses, is associated with an increased risk of cancer, cardiovascular disease, and cataracts [5]. Studies of atomic bomb survivors and nuclear industry workers show a clear correlation between radiation exposure and cancer incidence, particularly for leukemia, thyroid cancer, and lung cancer [6].

C. Genetic and Reproductive Effects

Ionizing radiation can cause mutations in DNA, leading to genetic disorders. These mutations can be passed on to future generations, raising concerns about genetic instability in populations exposed to radiation over multiple generations [7].

Non-Ionizing Radiation

Non-ionizing radiation, such as UV radiation, poses different health risks, often associated with long-term exposure rather than immediate effects.

D. Effects of Ultraviolet (UV) Radiation

UV radiation is the primary cause of skin cancer and premature aging of the skin. Chronic exposure to UV radiation increases the risk of melanoma and other skin cancers by causing DNA mutations [8].

E. Effects of Radiofrequency and Microwave Radiation

Although radiofrequency and microwave radiation do not ionize atoms, they can cause tissue heating and are associated with thermal damage, especially in high exposures. The International Agency for Research on Cancer (IARC) has classified radiofrequency electromagnetic fields as possibly carcinogenic (Group 2B), linking them to a potential increased risk of glioma [9].

Radiation Effects on Specific Organs

The impact of radiation varies based on the organ system exposed, with the following effects observed in specific organs:

• Brain and Central Nervous System: High doses can lead to radiation necrosis and  cognitive impairment [10].
• Cardiovascular System: Low to moderate exposure may increase the risk of heart disease and stroke [5].
• Reproductive System: Radiation can impair fertility and cause genetic mutations that affect offspring [11].

Principles of Radiation Protection

Radiation protection is based on three primary principles: time, distance, and shielding. Minimizing exposure time, maximizing distance from radiation sources, and using adequate shielding are fundamental to reducing exposure [2].

Regulatory Dose Limits

Regulatory bodies, including the International Commission on Radiological Protection (ICRP), and the Environmental Protection Agency (EPA), set dose limits to protect workers and the public. These limits are based on epidemiological data and aim to minimize cancer risks while allowing beneficial uses of radiation [2].

Shielding materials, such as lead for gamma rays and concrete for neutron shielding, are critical in reducing radiation exposure. Recent advancements include the development of lighter, flexible materials, such as lead-free composites for use in wearable protective garments [12].

Personal protective equipment, such as lead aprons, thyroid shields, and radiation-attenuating gloves, provide additional protection, especially in medical settings where healthcare workers are frequently exposed to diagnostic imaging equipment [13].

Emerging research focuses on biological countermeasures, including radio protective agents and antioxidants that can mitigate the harmful effects of radiation at the cellular level.

Amifostine, for example, is a radio protective agent used in radiation therapy to protect healthy tissues from damage [14].

Radiation exposure presents both acute and chronic health risks, necessitating comprehensive protection mechanisms to safeguard public health. Ionizing radiation’s effects are more pronounced due to its DNA-damaging capabilities, increasing cancer and genetic mutation risks, whereas non-ionizing radiation poses risks associated with prolonged exposure. Effective radiation protection strategies, including time, distance, shielding, and personal protective equipment, are essential, especially for medical professionals and radiation workers. Further research into biological protective agents could offer promising avenues for enhanced protection in high-exposure scenarios.

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