Sequoia National Park can lay claim to two superlatives — its redwoods are the oldest single organisms on the planet and its air quality is the worst of any national park in the country.

The smog pollution in the park is so bad that levels reach L.A.-worthy heights.

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The park might seem like it’s in the middle of nowhere. But that nowhere happens to be right near the San Joaquin Valley, which is full of food-processing plants, diesel-burning freight trains, and trucks driving down one of the busiest highways in the country.

According to the Associated Press, the awesome redwoods might not be affected by this … or they might be! No one really knows. The park service does realize, though, that breathing in a buttload of ozone isn’t great for human beings. Park workers are at risk of heart and lung damage, and the government warns potential employees that the park is an unhealthy workplace. Not exactly what most people think they’re signing up for when they apply to work among groves of stately giants.

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