cancer increased with radon concentration monotonically [5]. Analysis from
thirteen case-control studies conducted in nine European countries between 1982–
1995 also showed appreciable hazards from residential radon exposure, responsible
for an estimated 2% of all deaths from cancer in Europe [6]. The risk of lung cancer
increased by 8.4% per 100 Bq/m 3 (~2.7 pCi/L) increase in measured radon [6].
These residential studies provide evidence of a positive association between
residential radon exposure and lung cancer risk [7]. Currently, the World Health
Organization (WHO) and the United States Environmental Protection Agency
(USEPA) both classify radon as a leading causes of lung cancer, second only to
smoking.
Radon exposure at schools may have a considerable public health impact. It was
estimated that approximately 14% of the 300,000 annual lung cancer cases in the
United States are attributable to radon [8]. The risk of lung cancer in children
resulting from exposure to radon may be up to three- fold higher than that of adults
exposed to the same amount of radon [9] due to the morphometric differences
between the lungs of children and the lungs of adults [10], as well as higher
respiration rates of children compared with adults. Children also spend more time
indoors, and are generally more sensitive to environmental hazards exposure [11]. It
was estimated that U.S. children, on average, spend 6.64 h per day for 180 days per
year in school buildings [12]. This does not include the substantial additional hours
that children might spend in school buildings in after-school programs. Schools are
also workplaces for teachers and administrators and service staff, who might spend
even more time than children in school buildings. In the late 1980s, short-term
radon measurements were conducted in 3000 rooms in 130 U.S. schools in 16 states
[13]. Over half of the schools had at least one room with radon levels above 4
pCi/L, and all 16 tested states had some classrooms with radon above 4 pCi/L, with
the highest classroom showing 136.2 pCi/L. Therefore, high levels of radon in
school buildings may pose significant health risks to those who spend many
months, or years, at those schools [14].
Given the lack of U.S. Federal regulations concerning radon levels in schools, we
reviewed specific state statutes on radon that could influence exposure to school
children, including bills that passed in the 2017 U.S. legislative sessions. We further
discuss Federal and state regulations as they relate to radon reduction and control,
radon testing, dissemination of radon levels to the public, radon mitigation, and
various challenges and policy recommendations.
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