system
Given the following post, respond as if you're commenting on Reddit:
human
[Biology] Why do dogs smell so bad when wet?
gpt
Even on the cleanest, healthiest dogs, millions of yeast and bacteria call the fur home.  They produce a lot of volatile organic compounds, such as phenols and aldehydes.  These compounds don't get a chance to fully assault your nostrils until they are liberated by water; as the water evaporates to vapor, it is carried to your olfactory receptors more easily (humidity helps to hold odor molecules suspended in the air).