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