Breathtaking art under threat from exhalation The magnificent frescoes housed in the Sistine Chapel in Vatican City are under threat from the very visitors who flock to see the work of Michelangelo and Botticelli. The Vatican Museum has installed some 50 sensors that measure temperature, humidity and levels of carbon monoxide in the chapel as the very breath of art lovers eats away at the century's old works. More about: Pollution, Vatican