Threshold Limit Values committee

The Chemical Substances Threshold Limit Values Committee classifies certain substances found in the occupational environment as either confirmed or suspected human... 

The Chemical Substances Threshold Limit Values Committee classifies certain substances found in the occupational environment as either confirmed or suspected human carcinogens. The present listing of substances that have been identified as carcinogens takes two forms those for which a TLV has b n assigned and those for which environmental and exposure conditions have not been sufficiently defined to assign a TLV. Where a TLV has been assigned, it does not necessarily imply the existence of a biological threshold however, if exposures are controlled to this level, we would not expect to see a measurable increase in cancer incidence or mortality. 

Elizabeth K. Weisburger. History and background of the Threshold Limit Value Committee of the American Conference of Governmental Industrial Hygienists. Journal of Chemical Health and Safety 8(4) 10-12 (2001). 

Joint Expert Committee on Food Additives does not give an acceptable daily intake level. The American Conference of Governmental Industrial Hygienists threshold limit value, 8h time-weighted average is 10 ppm. 

Threshold Limits Committee Threshold Limit, Values of Airbone Contaminants, Cincinnati, OH, American Conference of Governmental Industrial Hygienists (published annually)... 

There are no established tolerances for chlordane or heptachlor in the ambient air in home environments. An interim guideline level of 5.0 pg/m3 (chlordane) and 2.0 pg/m (heptachlor) has been recommended by the Committee on toxicology of the National Academy of Sciences (8). The maximum allowable limit in work-space air during a 40 h workweek (Threshold Limit Value, Time Weighted Average) (TLV-TWA) is 500 pg/m for chlordane and heptachlor (9). 

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