The Daphnia consumed these particles, and scientists found that, while the larger particles didn't seem to affect them, the smallest particles — around 50 nanometers — were deadly.

水蚤吃掉了这些颗粒，然后科学家发现，较大的颗粒似乎不会影响它们，但大约50纳米的那些小颗粒是致命的。