The odor threshold for hydrogen cyanide is 0.58 parts per million (ppm).

Therefore, the odor concentration at the odor threshold is 1 OU by definition.

The odor threshold of p-xylene is 0.62 parts per million (ppm).

By contrast, ammonia has an odor threshold of 17 parts per million.

(1) The odor threshold for ethylbenzene is 2.3 parts per million (ppm).

An odor threshold of 1 ppb has been reported.

Both compounds have odor thresholds below 0.06 ng/l.

One favorable safety aspect is that ethyl acrylate has good warning properties; the odor threshold is much lower than any level of health concern.

Replies: No promises here because the odor threshold of some of these compounds is very low.

It has an odor threshold of 200 ppb and constitutes 0.16% of Bulgarian rose oil.