§ 795.225 Dermal pharmacokinetics of DGBE and DGBA.
(a) Purpose. The purpose of these studies is to determine:
(1) The absorption of diethylene glycol butyl ether (DGBE) after administration by the dermal route.
(2) The biotransformation of DGBE administered dermally.
(3) The dermal absorption of DGBE and diethylene glycol butyl ether acetate (DGBA).
(b) Test procedures—(1) Animal selection—(i) Species. The species utilized for investigating DGBE and DGBA shall be the rat, a species for which historical data on the toxicity and carcinogenicity of many compounds are available and which is used extensively in percutaneous absorption studies.
(ii) Animals. Adult female Sprague Dawley rats shall be used. The rats shall be 7 to 8 weeks old and weigh 180 to 220 grams. Prior to testing, the animals shall be selected at random for each group. Animals showing signs of ill health shall not be used.
(iii) Animal care. (A) The animals should be housed in environmentally controlled rooms with 10 to 15 air changes per hour. The rooms should be maintained at a temperature of 25 ±2 °C and humidity of 50 ±10 percent with a 12-hour light/dark cycle per day. The rats should be isolated for at least 7 days prior to use.
(B) During the acclimatization period, the rats should be housed in cages on hardwood chip bedding. All animals shall be provided with conventional laboratory diets and water ad libitum.