Radiation burn

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(Redirected from
Radiation acne
)
Radiation burn
Other namesRadiodermatitis
Ionizing radiation burn: large red patches of skin on the back and arm from multiple prolonged fluoroscopy procedures
SpecialtyDermatology Edit this on Wikidata

A radiation burn is a damage to the

ultraviolet light and ionizing radiation
.

The most common type of radiation

beta particles are not able to penetrate deeply into a body; these burns can be similar to sunburn. Alpha particles
can cause internal alpha burns if inhaled, with external damage (if any) being limited to minor erythema.

Radiation burns can also occur with high power

radio transmitters at any frequency where the body absorbs radio frequency energy and converts it to heat.[1] The U.S. Federal Communications Commission (FCC) considers 50 watts to be the lowest power above which radio stations must evaluate emission safety. Frequencies considered especially dangerous occur where the human body can become resonant, at 35 MHz, 70 MHz, 80-100 MHz, 400 MHz, and 1 GHz.[2] Exposure to microwaves of too high intensity can cause microwave burns
.

Types

Radiation dermatitis (also known as radiodermatitis) is a

skin disease associated with prolonged exposure to ionizing radiation.[3]: 131–2  Radiation dermatitis occurs to some degree in most patients receiving radiation therapy, with or without chemotherapy.[4]

There are three specific types of radiodermatitis: acute radiodermatitis, chronic radiodermatitis, and eosinophilic, polymorphic, and pruritic eruption associated with radiotherapy.[3]: 39–40  Radiation therapy can also cause radiation cancer.[3]: 40 

With interventional fluoroscopy, because of the high skin doses that can be generated in the course of the intervention, some procedures have resulted in early (less than two months after exposure) and/or late (two months or more after exposure) skin reactions, including necrosis in some cases.[5]: 773 

Radiation dermatitis, in the form of intense erythema and vesiculation of the skin, may be observed in radiation ports.[3]: 131 

As many as 95% of patients treated with radiation therapy for cancer will experience a skin reaction. Some reactions are immediate, while others may be later (e.g., months after treatment).[6]

Acute

Acute radiodermatitis occurs when an "erythema dose" of ionizing radiation is given to the skin, after which visible erythema appears up to 24 hours after.[3]: 39  Radiation dermatitis generally manifests within a few weeks after the start of radiotherapy.[4]: 143  Acute radiodermatitis, while presenting as red patches, may sometimes also present with desquamation or blistering.[7] Erythema may occur at a dose of 2 Gy radiation or greater.[8]

Chronic

Chronic radiodermatitis on the neck and jaw from X-ray exposure

Chronic radiodermatitis occurs with chronic exposure to "sub-erythema" doses of ionizing radiation over a prolonged period, producing varying degrees of damage to the skin and its underlying parts after a variable latent period of several months to several decades.

radiologists and radiographers who were constantly exposed to ionizing radiation, especially before the use of X-ray filters.[3]
: 40  Chronic radiodermatitis, squamous and basal cell carcinomas may develop months to years after radiation exposure.[7]: 130 [9] Chronic radiodermatitis presents as atrophic indurated plaques, often whitish or yellowish, with telangiectasia, sometimes with hyperkeratosis.[7]: 130 

Other

Eosinophilic, polymorphic, and pruritic eruption associated with radiotherapy is a skin condition that occurs most often in women receiving cobalt radiotherapy for internal cancer.[3]: 39–40 

Radiation-induced erythema multiforme may occur when phenytoin is given prophylactically to neurosurgical patients who are receiving whole-brain therapy and systemic steroids.[3]: 130 

Delayed effects

Radiation acne is a cutaneous condition characterized by comedo-like papules occurring at sites of previous exposure to therapeutic ionizing radiation, skin lesions that begin to appear as the acute phase of radiation dermatitis begins to resolve.[10]: 501 

Radiation recall reactions occur months to years after radiation treatment, a reaction that follows recent administration of a chemotherapeutic agent and occurs with the prior radiation port, characterized by features of radiation dermatitis.[3][11] Restated, radiation recall dermatitis is an inflammatory skin reaction that occurs in a previously irradiated body part following drug administration.[12] There does not appear to be a minimum dose, nor an established radiotherapy dose relationship.[12]

Alpha burns

"Alpha burns" are caused by alpha particles, which can cause extensive tissue damage if inhaled.[13] Due to the keratin in the epidermal layer of the skin, external alpha burns are limited to only mild reddening of the outermost layer of skin.[14]

Beta burns

"Beta burns"—caused by beta particles—are shallow surface burns, usually of skin and less often of lungs or gastrointestinal tract, caused by beta particles, typically from hot particles or dissolved radionuclides that came to direct contact with or close proximity to the body. They can appear similar to sunburn. Unlike gamma rays, beta emissions are stopped much more effectively by materials and therefore deposit all their energy in only a shallow layer of tissue, causing more intense but more localized damage. On cellular level, the changes in skin are similar to radiodermatitis.

The dose is influenced by relatively low penetration of beta emissions through materials. The

epidermis has enough stopping power to absorb beta radiation with energies lower than 70 keV. Further protection is provided by clothing, especially shoes. The dose is further reduced by limited retention of radioactive particles on skin; a 1 millimeter particle is typically released in 2 hours, while a 50 micrometer particle usually does not adhere for more than 7 hours. Beta emissions are also severely attenuated by air; their range generally does not exceed 6 feet (1.8 m) and intensity rapidly diminishes with distance.[15]

The

Safety goggles are recommended to attenuate strong beta.[17]

Careful washing of exposed body surface, removing the radioactive particles, may provide significant dose reduction. Exchanging or at least brushing off clothes also provides a degree of protection.

If the exposure to beta radiation is intense, the beta burns may first manifest in 24–48 hours by itching and/or burning sensation that last for one or two days, sometimes accompanied by

nasopharyngeal region, ingestion may lead to burns of gastrointestinal tract; the latter being a risk especially for grazing
animals.

Lost hair begins regrowing in nine weeks and is completely restored in about half a year.[19]

The acute dose-dependent effects of beta radiation on skin are as follows:[20]

0–6 Gy no acute effect
6–20 Gy moderate early erythema
20–40 Gy early erythema in 24 hours,
skin breakdown
in 2 weeks
40–100 Gy severe erythema in less than 24 hours
100–150 Gy severe erythema in less than 4 hours, skin breakdown in 1–2 weeks
150–1000 Gy blistering immediate or up to 1 day

According to other source:[21]

2–6 Gy transient erythema 2–24 h
3–5 Gy dry desquamation in 3–6 weeks
3–4 Gy temporary epilation in 3 weeks
10–15 Gy erythema 18–20 days
15–20 Gy moist desquamation
25 Gy ulceration with slow healing
30–50 Gy blistering, necrosis in 3 weeks
100 Gy blistering, necrosis in 1–3 weeks

As shown, the dose thresholds for symptoms vary by source and even individually. In practice, determining the exact dose tends to be difficult.

Similar effects apply to animals, with fur acting as additional factor for both increased particle retention and partial skin shielding. Unshorn thickly wooled sheep are well protected; while the epilation threshold for sheared sheep is between 23 and 47 Gy (2500–5000

rep) and the threshold for normally wooled face is 47–93 Gy (5000–10000 rep), for thickly wooled (33 mm hair length) sheep it is 93–140 Gy (10000–15000 rep). To produce skin lesions comparable with contagious pustular dermatitis, the estimated dose is between 465 and 1395 Gy.[22]

Energy vs penetration depth

Medium-lived
fission products[further explanation needed]
t½
(year
)
Yield
(%)
keV
)
βγ
155Eu
4.76 0.0803 252 βγ
85Kr 10.76 0.2180 687 βγ
113mCd
14.1 0.0008 316 β
90Sr 28.9 4.505   2826 β
137Cs 30.23 6.337   1176 βγ
121mSn
43.9 0.00005 390 βγ
151Sm
88.8 0.5314 77 β

The effects depend on both the intensity and the energy of the radiation. Low-energy beta (sulfur-35, 170 keV) produces shallow ulcers with little damage to dermis, while

high-Z elements generate deeply penetrating gamma bremsstrahlung
.

The electron energies from

antineutrino which does not significantly interact and therefore does not contribute to the dose. Most energies of beta emissions are at about a third of the maximum energy.[17]
Beta emissions have much lower energies than what is achievable from particle accelerators, no more than few megaelectronvolts.

The energy-depth-dose profile is a curve starting with a surface dose, ascending to the maximum dose in a certain depth dm (usually normalized as 100% dose), then descends slowly through depths of 90% dose (d90) and 80% dose (d80), then falls off linearly and relatively sharply though depth of 50% dose (d50). The extrapolation of this linear part of the curve to zero defines the maximum electron range, Rp. In practice, there is a long tail of weaker but deep dose, called "bremsstrahlung tail", attributable to bremsstrahlung. The penetration depth depends also on beam shape, narrower beam tend to have less penetration. In water, broad electron beams, as is the case in homogeneous surface contamination of skin, have d80 about E/3 cm and Rp about E/2 cm, where E is the beta particle energy in MeV.[24]

The penetration depth of lower-energy beta in water (and soft tissues) is about 2 mm/MeV. For a 2.3 MeV beta the maximum depth in water is 11 mm, for 1.1 MeV it is 4.6 mm. The depth where maximum of the energy is deposited is significantly lower.[25]

The energy and penetration depth of several isotopes is as follows:[26]

isotope half-life specific activity
(TBq/g)
avg.
(keV)
max.
(keV)
in air
(mm)
in tissue
(mm)
comment
tritium 12.3 years 357 5.7 18.6 6 0.006 no beta passes the dead layer of skin; however, tritium and its compounds may diffuse through skin
carbon-14 5730 years 0.165 49 156 240 0.28 about 1% of beta passes through the dead layer of skin
sulfur-35
87.44 days 1580 48.8 167.47 260 0.32
phosphorus-33
25.3 days 5780 76.4 248.5 500 0.6
phosphorus-32 14.29 days 10600 695 1710 6100 7.6 risk of Bremsstrahlung if improperly shielded

For a wide beam, the depth-energy relation for dose ranges is as follows, for energies in

megaelectronvolts and depths in millimeters. The dependence of surface dose and penetration depth on beam energy is clearly visible.[24]

MeV surface
dose %
max.
depth
90% 80% 50% 10% Rp
5 74% 9 12 14 17 22 23
7 76% 16 20 22 27 33 34
10 82% 24 31 34 39 48 49
13 88% 32 40 43 51 61 64
16 93% 34 51 56 65 80 80
19 94% 26–36 59 67 78 95 95
22 96% 26–36 65 76 93 113 114
25 96% 26–36 65 80 101 124 124

Causes

Radiation burns are caused by exposure to high levels of radiation. Levels high enough to cause burn are generally lethal if received as a whole-body dose, whereas they may be treatable if received as a shallow or local dose.

Medical imaging

Fluoroscopy may cause burns if performed repeatedly or for too long.[10]

Similarly, X-ray

projectional radiography
have the potential to cause radiation burns if the exposure factors and exposure time are not appropriately controlled by the operator.

A study of radiation-induced skin injuries[27][28] has been performed by the Food and Drug Administration (FDA) based on results from 1994,[29] followed by an advisory to minimize further fluoroscopy-induced injuries.[30] The problem of radiation injuries due to fluoroscopy has been further investigated in review articles in 2000,[31] 2001,[32][33] 2009[34] and 2010.[35][36][37]

Radioactive fallout

Beta burns are frequently the result of exposure to

fission products
have very high beta activity, with about two beta emissions per each gamma photon.

After the

Trinity test, the fallout caused localized burns on the backs of cattle in the area downwind.[38] The fallout had the appearance of small flaky dust particles. The cattle showed temporary burns, bleeding, and loss of hair. Dogs were also affected; in addition to localized burns on their backs, they also had burned paws, likely from the particles lodged between their toes as hoofed animals did not show problems with feet. About 350–600 cattle were affected by superficial burns and localized temporary loss of dorsal hair; the army later bought 75 most affected cows as the discolored regrown hair lowered their market value.[39] The cows were shipped to Los Alamos and Oak Ridge, where they were observed. They healed, now sporting large patches of white fur; some looked as if they had been scalded.[40]

The fallout produced by the

USS Bairoko received beta burns, and there was an increased cancer rate.[15]

During the Zebra test of the

skin grafts. A fourth man showed weaker burns after the earlier Yoke test.[42]

The Upshot–Knothole Harry test at the Frenchman Flat site released a large amount of fallout. A significant number of sheep died after grazing on contaminated areas. The AEC however had a policy to compensate farmers only for animals showing external beta burns, so many claims were denied. Other tests on the Nevada Test Site also caused fallout and corresponding beta burns to sheep, horses and cattle.[43] During the Operation Upshot–Knothole, sheep as far as 50 miles (80 km) from the test site developed beta burns to their backs and nostrils.[42]

During underground nuclear testing in Nevada, several workers developed burns and skin ulcers, in part attributed to exposure to tritium.[44]

Nuclear accidents

Beta burns were a serious medical issue for some victims of the

basal layer of the skin, resulting in large area portals for infections, exacerbated by damage to bone marrow and weakened immune system. Some patients received skin dose of 400–500 Gy. The infections caused more than half of the acute deaths. Several died of fourth degree beta burns between 9–28 days after dose of 6–16 Gy. Seven died after dose of 4–6 Gy and third degree beta burns in 4–6 weeks. One died later from second degree beta burns and dose 1-4 Gy.[44] The survivors have atrophied skin which is spider veined and with underlying fibrosis.[15]

The burns may manifest at different times at different body areas. The Chernobyl liquidators' burns first appeared on wrists, face, neck and feet, followed by chest and back, then by knees, hips and buttocks.[45]

Industrial radiography sources are a common source of beta burns in workers.

Radiation therapy sources can cause beta burns during exposure of the patients. The sources can be also lost and mishandled, as in the Goiânia accident, during which several people had external beta burns and more serious gamma burns, and several died. Numerous accidents also occur during radiotherapy due to equipment failures, operator errors, or wrong dosage.

Electron beam sources and particle accelerators can be also sources of beta burns.[46] The burns may be fairly deep and require skin grafts, tissue resection or even amputation of fingers or limbs.[47]

Treatment

Radiation burns should be covered by a clean, dry dressing as soon as possible to prevent infection. Wet dressings are not recommended.[48] The presence of combined injury (exposure to radiation plus trauma or radiation burn) increases the likelihood of generalized sepsis.[49] This requires administration of systemic antimicrobial therapy.[50]

See also

References

  1. ^ ARRL: RF Exposure Regulations News Archived 2008-05-17 at the Wayback Machine
  2. ^ ARRL: RF Radiation and Electromagnetic Field Safety
  3. ^ .
  4. ^ .
  5. .
  6. .
  7. ^ .
  8. .
  9. .
  10. ^ .
  11. ^ Hird AE, Wilson J, Symons S, Sinclair E, Davis M, Chow E. Radiation recall dermatitis: case report and review of the literature. Current Oncology. 2008 February; 15(1):53-62.
  12. ^
    S2CID 10211887
    .
  13. .
  14. ^ "Multi-side Approach to the Realities of the Chernobyl NPP Accident" (PDF). Kyoto University, Research Reactor Institute. Retrieved May 16, 2019.
  15. ^ .
  16. .
  17. ^ .
  18. .
  19. .
  20. ^ a b United States. Dept. of the Army (1990). Nuclear handbook for medical service personnel. p. 18.
  21. ^ Medical decision making and care of casualties from delayed effects of a nuclear detonation[permanent dead link], Fred A. Mettler Jr., New Mexico Federal Regional Medical Center
  22. .
  23. .
  24. ^ .
  25. ^ α, β, γ Penetration and Shielding. Fas.harvard.edu.
  26. ^ Isotope Safety Data Sheets
  27. ^ Shope, T. B. (1995). "Radiation-induced Skin Injuries from Fluoroscopy". FDA / Center for Devices and Radiological Health.
  28. PMID 8888398
    .
  29. .
  30. ^ "FDA Public Health Advisory: Avoidance of Serious X-Ray-Induced Skin Injuries to Patients During Fluoroscopically-Guided Procedures". FDA / Center for Devices and Radiological Health. September 30, 1994.
  31. S2CID 70923586
    .
  32. .
  33. .
  34. .
  35. .
  36. .
  37. .
  38. ^ a b National Research Council (U.S.). Committee on Fire Research, United States. Office of Civil Defense (1969). Mass burns: proceedings of a workshop, 13–14 March 1968. National Academies. p. 248.
  39. . beta burns.
  40. .
  41. .
  42. ^ .
  43. .
  44. ^ .
  45. .
  46. .
  47. .
  48. ^ Of The Army, United States. Dept (1982). Nuclear handbook for medical service personnel.
  49. PMID 21233728
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  50. .

External links