Mercury – the famously liquid, famously toxic metal – is a contaminant with a worldwide scope. Of course, the beauty of studying global contaminants is that you get to see the globe. If you had asked me a year ago if I wanted to go to the Canary Islands, my answer would have been a deep sigh, a murmured “yes,” and a wistful gaze at the horizon. Imagine my delight on discovering there are legitimate scientific reasons to travel to spectacular tropical locales.