Alpha-emitting radiation (None (commonly referred to as "alpha radiation" but no formal abbreviation))

Alpha-emitting radiation consists of helium nuclei ejected by unstable isotopes (such as radium-223, actinium-225, bismuth-213, and others)[5][9]. The particles possess high energy but extremely short tissue penetration (less than 0.1 mm), making them toxic to cells they contact but generally sparing nearby healthy tissue if selectively delivered[7][8]. In medicine, alpha-emitting radiopharmaceuticals are attached to tumor-targeted carriers (like antibodies or peptides) in targeted alpha therapy (TAT). When administered, they release alpha radiation directly to cancer cells, massively damaging their DNA and inducing cell death[1][7]. This approach allows localized tumor destruction with minimized side effects compared to broader radiation[8][9]. Alpha particles are also significant environmental carcinogens if internalized, exemplified by radon causing lung cancer after inhalation[4][5]. Their use is expanding in oncology, with agents like radium-223 already in clinical use for prostate cancer bone metastases[3][6][9].

Other names

Alpha radiationAlpha particle radiationAlpha particlesAlpha-emitter therapyTargeted alpha therapy (TAT)

High-energy alpha particles cause double-strand DNA breaks and complex DNA lesions in targeted cells, leading to cell cycle arrest and death[6][8][9] Activation of DNA damage signaling pathways, including ATM and MAP kinases; induction of apoptosis via sphingomyelin pathway[2][6] Membrane damage and generation of reactive oxygen species; possible effects on surrounding cells ("bystander effect")[2]