No. The smoke used for this type of testing is non-toxic and non-hazardous, has little odor and creates no fire hazard. It is manufactured specifically for this purpose.
The smoke SCU utilizes is commonly used in the industry and while it is not considered harmful, it is recommended to avoid prolonged periods of exposure. Should smoke appear from a drain or vent inside your residence, open windows and ventilate well to dissipate the smoke.
Sanitary Sewer Smoke Testing