Safety evaluation of wood-based activated carbon fibers in a 28-day feeding study in Sprague-Dawley rats

Abstract

As a possible food moisture-proof material, wood-based activated carbon fibers (WACFs), prepared from one type of wood pulp: Laubholz Unbleached Kraft Pulp (LUKP) by the physical activation method with steam at an 850°C activation temperature with 60 min of activation time (850 LUKP WACFs), were evaluated in a 28-day feeding study of Sprague-Dawley rats (SD rats) after the Ames test had been carried out in a previous paper. SD rats were randomly distributed into five groups, including a blank group (reverse osmosis water), a control group (saline), and groups with low, moderate, and high (1.0, 2.5, and 5.0 g/kg/day, respectively) doses of 850 LUKP WACFs. All SD rats were sacrificed after a 28-day feeding toxicity study. Blood samples were analyzed for hematological and serum biochemical values, and histopathological examinations of the organs were investigated. There were insignificant differences from the clinical pathology; that is, no observable adverse effect levels (NOAEL) of 850 LUKP WACFs greater than 5.0g/kg/day. It is suggested that WACFs prepared from wood pulp can be a potential type of food moisture-proof material and a potential type of material for water quality improvement due to their biological safety results.