At the end of the 8 h sunlight
exposure period, beakers were covered with
Parafilm, placed in the dark in an ice-filled cooler, and
returned to the lab where they were stored overnight
under refrigeration (4+18C) in the dark. Less than
24 h later, toxicity assays with the model test organism,
the fat-head minnow Pimephales promelas were initiated
with samples from the light exposure study