Previously, an elaborate cotton blending and dust collection protocol was developed and implemented to produce uniform, vertically elutriated dust samples that were used in a two-part interlaboratory endotoxin assay study. The results from that study generated interest in extending the interlaboratory endotoxin assay study. To satisfy this need, a second series of dust samples on glass filters, as well as on the polyvinyl chloride filters used previously, were collected. Three sources of cotton were used. The cottons were blended to produce a uniform and homogenized cotton, and then carded. The dust collection was made on vertical elutriators using the model cardroom at the Cotton Quality Research Station in Clemson, SC. Dust samples containing a low, medium and high endotoxin concentration were obtained. A full 120 separate collection runs were made and they resulted in more than 1500 dust samples on polyvinyl chloride filters and 1500 dust samples on glass filters, each with 0.3 to 0.8 mg cotton dust per filter. The dust samples collected should satisfy the need for dust samples for present and future endotoxin assay studies.