In industrial exposure to gaseous and particulate fluoride, absorption is mainly through the respiratory tract. Fluoride absorbed into the body is handled in two ways; by deposition in the skeletal system, and/or by urinary excretion.
Urinary excretion is prompt and closely related to the amount absorbed. This rapidity of excretion, and the variations in nature and magnitude of exposure during a working day make it impossible to assess general working conditions from a single spot urine from a single individual.
It is not considered necessary for the majority of workers exposed to fluoride to have regular urinary fluoride estimations. However, if, because of work practices, this is considered necessary, end-of-shift urine samples should be taken after four or more consecutive days of exposure.
If the pre-shift sample exceeds the recommended level, or the repeat post-shift sample exceeds the recommended level then the dietary sources (e.g. tea, coffee), personal hygiene, basic work practices and environmental control need to be evaluated.
Pre-shift samples are considered to be a measure of the workers body (skeletal) burden of fluoride. While the post-shift sample is considered to be representative of exposure conditions during that shift.
Lipids/Trace Metals
WFL
7 days
4068