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Chernobyl’s Subclinical Legacy: Prenatal Exposure To
Radioactive Fallout And School Outcomes In Sweden
Douglas AlmondLena Edlund
Marten Palme
CHERNOBYL ACCIDENT
Pictures sources:http://faculty.virginia.edu/metals/cases/kleinfeld3.htmlhttp://www.chernobylee.com/blog/2008/10/chernobyl-fallout-greater-in-s.php
CHERNOBYL ACCIDENT
Weather conditions caused it to receive about 5% of the accident’s cesium fallout
Background
Empirical studies in the human capital tradition have sought to isolate the role of latent variables – such as ability or family background – from differences in other inputs or production technologies.
A natural experiment could help. The magnitude of the reduced form impact on human
capital formation could be assessed. With data on baseline characteristics (e.g., family
background), we could observe how predetermined factors interact with the latent input in producing human capital.
The radioactive fallout from the 1986 Chernobyl accident in Sweden offers a natural experiment in cognitive ability.
Research question
Do radioactive fallout from the 1986 Chernobyl accident in Sweden affect the cognitive ability due to the prenatal radiation exposure ?
The Chernobyl accident
The core meltdown at Chernobyl occurred at 1:24 am April 26, 1986 in Ukraine. News of the accident came from Sweden, where heightened levels of radioactivity set off alarm bells at the Swedish nuclear plant Forsmark, some 680 miles away.
The Chernobyl accident provides a nearly ideal natural experiment in radiation exposure. Meteorological conditions resulted in Sweden receiving about 5 percent of the Caesium fallout, creating a pronounced spike in radiation levels.
There was also substantial geographic variation in deposition due primarily to differences in rainfall at the time of the accident
Daily Gamma Radiation in Njurunda, Sweden Source. Kjelle (1987)
Weather conditions caused it to receive about 5% of the accident’s cesium fallout
AREA
Figure II
SWEDISH SCHOOL SYSTEM
English SwedishMathematics
SwedishMathematics
Data
Radiation data from the Swedish Geological Co. (SGAB) Aerial measurements of ground deposition °-
radiation from Caesium-137 (May-October 1986) for 2,380 parishes (out of 2,517), and then aggregate to the municipality or county level.
In-situ gammaspectrometric measurements using high-resolution Gedetectors at 61 locations covering 48 municipalities
Based on the information from the aerial measurements and in situ measurements, we classify Sweden into four groups as detailed in Table I and mapped in Figure III.
GRADES
GRADES
DATA
Figure III
Data
School outcomes Compulsory school
children born between 1983-1988 Qualify to High School Average Grade
High school (73 percent), average and individual grades in Mathematics and
Swedish.
Control variables Parental education Local labor market condition
Birth Outcomes (Swedish birth register since 1973). birth weight (grams) gestation length (in days) Apgar score (test conducted 5 minutes after birth),
ranging scores 0-10 (no problems) Hospital data
Congenital malformations (ICD-7 750-759) Mental, nervous and sensory disorders Neoplasms Days Hospitalized
Hospital data Congenital malformations (ICD-7 750-759) Mental, nervous and sensory disorders Neoplasms Days Hospitalized
Estimation (radiation dummies)
Figure IV: Fraction of qualified to enter high school
Figure V: Diff in mean grade
Figure VI: Diff in math grade
Estimation (radiation continuous)
Measurement Error: IV