Can you imagine that several hundred years ago, tomatoes were seen as _ food in Europe? What made Europeans believe this was John Gerard's publication of Herbal in 1597. Gerard wrote: "The leaves and stalks of the tomato plant are toxic." Undoubtedly, Gerard's opinion was based on a misunderstanding of tomatoes. But his opinion was widely spread in Britain and North America for over two hundred years. In the late 1700s, a lot of Europeans held more fears for tomatoes. A nick name for the fruit was "poison apple" because it was believed that aristocrats  got sick and died after eating them. But the actual reason was the pewter plates they used. Since tomatoes are high in acidity, when placed on the plates, the lead  in the plates would dissolve . This caused many deaths. Unluckily, no one knew this at that time. So the innocent tomatoes were picked as the killer. Today, more than one and a half billion tons of tomatoes are produced every year around the world. Tomatoes are cooked in various ways. This healthy and tasty food finally wins its innocence  back. What's the key point for the death of the aristocrats mentioned in the passage?
Tomatoes. The pewter plate. Serious illness. Chemical reaction.