Registration Dossier

Administrative data

Description of key information

There is one reliable human clinical study (Dow Corning Corporation, 1997d) and some employee health surveillance data, which is of unknown reliability as the original study report was not available for review (Dow Corning Corporation, 1977).

Additional information

In a human clinical study (Dow Corning Corporation, 1997d), the respiratory intake and uptake of D4 were measured in 12 healthy volunteers following exposure to 10 ppm for 1 hour. Mean D4 intake was 137 +/- 25 mg (SD). Plasma measurement of D4 gave a mean peak value of 79 +/- 5 ng/g (SEM) and indicated a rapid nonlinear blood clearance. 


In a health evaluation of employees exposed to D4 conducted to determine whether measurable health effects are produced by long-term exposure to typical concentrations of D4 in the workplace (Dow Corning Corporation, 1977), the 8 hour TWA exposure to D4 was found to range from 0.17 to 2.2 ppm with an average of 0.75 ppm. The highest concentration found during the survey was 4.4 ppm. The results indicate that there are no measurable health effects produced by long-term exposures to typical levels of D4 found in the workplace.