According to the internet, a “positive test” for Cocaine is usually 0.3mg/L.
Some medical article I read said that it takes, on average, roughly 183mg/L to cause cardiac arrest, but obviously some people will be more susceptible.
I would consider it low, however, if this is a legal issue the any level might be considered to much.
I do not know the length of time cocaine stays in the human body, and what that means with regards to how long it has been since you (or whoever) had cocaine, etc.