Chemical and physical properties of processed newspaper compared to wheat straw and wood shavings as animal bedding.

Because of continuing concerns about the safety and the suitability of recycled newspaper as an animal bedding material, municipal curbside-collected newspaper was processed into chopped and pelleted forms for comparison studies with wheat straw and kiln-dried pinewood shavings. Measurements included nutrient, heavy metal, dioxin and furan content, particle size distribution, density, combustion potential, and water-holding capacity. Recycled newspaper, straw, and wood shavings tested below or equivalent to National Research Council dietary tolerance levels and US Environmental Protection Agency toxic equivalent levels. Small particle size distribution was shavings > straw > all forms of newspaper. The density of pelleted newspaper was 50-fold greater than that of chopped newspaper and straw and 15-fold greater than shavings. In simulated flash burns, chopped newspaper, straw, and shavings ignited, and flames spread rapidly in newspaper and shavings and lasted the longest in shavings. Pelleted newspaper did not ignite. Chopped and pelleted forms of newspaper and wood shavings had higher water holding capacities (>400%) than did straw (200%). Animal industries can, in confidence, utilize recycled newspaper as an animal bedding material, providing that sources of low toxicity are identified, and suitable processed forms are produced.