MOD 5 - Early Radiation Effects

Acute Radiation Syndrome

collective term used for early effects of whole body, high dose exposures

ARS Response Period

minutes - months

somatic effects

experienced by the individual exposed, not genetic

deterministic effects

effects determined by the amount of exposure (both chance of occurrence and severity of effect rises with dose)

three syndromes of ARS

• hematopoietic

• GI

• Cerebrovascular

Hematopoietic Syndrome exposure range and fatal period

• seen within whole body exposures range from 1-10 Gy

• Death occurs due to complications of blood cell destruction in the bone marrow (6-8 weeks)

GI Syndrome exposure range and fatal period

• seen within whole body, high dose exposures in the range of 6 -10 Gy

• death occurs due to a combination of dehydration, infection and hemorrhage, unable to absorb nutrients (3-10 days)

stages of GI Syndrome

• prodromal (early symptoms)

• latent (up to several days)

• manifest

Cerebrovascular Syndrome exposure range and fatal period

• seen within whole body, high dose exposure to radiation of 50 Gy or more

• death occurs due to extreme inflammation leading to edema and swelling in the brain (few hours - few days)

(LD50/30)

Lethal Dose 50% in 30 days

• 50% of an adult population is expected to die within 30 days without medical support if they receive whole body exposures between 3-4 Gy

early tissue reactions

• considered a deterministic effect

• symptoms of partial body high dose exposures

eg. early tissue reactions

• hair loss (epilation)

• skin burn

• reduced fertility

• permanent sterility

high dose is

> 1 Gy

medical imaging dose is

• <0.1 Gy

• >100mSv