Ground-level ozone exceeded
legal limits in every Member State and at
many individual measurement sites during
summer 2013, according to the European Environment
Agency's annual report on this harmful pollutant.
Although the number of exceedances is high,
they have decreased over recent decades,
the report notes.
Ozone pollution significantly
exceeded EU standards to protect health
during the summer of 2013, particularly
during July and the first days of August.
The most problematic areas were the Mediterranean
and Alpine regions. In some countries up
to two fifths of the population was exposed
to levels exceeding limits, the report says.
Recent scientific studies
have shown that ground-level ozone pollution
is harmful even at very low levels. This
means that levels are still far too high,
even though the the limits were exceeded
on fewer occasions than in many previous
years. Moreover, this does not necessarily
mean that exposure is falling a corresponding
amount. A separate study found that in 2012,
almost all inhabitants of cities in the
EU were exposed to ozone levels above World
Health Organisation guidelines, which are
stricter than the EU limits.
Ground-level ozone is
a 'secondary pollutant', which means it
is formed in chemical reactions between
other pollutants in the air. It is a particular
problem during the summer as it forms in
warm weather. High ozone concentrations
can cause serious health problems, especially
respiratory illnesses and cardiovascular
problems, leading to premature death in
some cases. It also damages vegetation such
as agricultural crops.
Key findings
The long-term objective
(LTO) for the protection of human health
(a maximum daily eight-hour mean concentration
of 120 µg/m3) was exceeded at least
once in all Member States and overall at
83 % of all reporting stations. Although
the number of exceedances is still very
high, it is the lowest percentage since
reporting started in 1997.
The LTO was exceeded
on more than 25 days across a significant
part of Europe.
The so-called 'information threshold' (a
one-hour average ozone concentration of
180 µg/m3) was exceeded at approximately
26 % of all operational stations, one of
the lowest percentages since 1997. In Northern
Europe, the information threshold was not
exceeded at all in 2013.
The 'alert threshold' (a one-hour average
ozone concentration of 240 µg/m3)
was exceeded 27 times, again one of the
lowest numbers on record.