Tampons were tested for effect on growth and production of toxic shock syndrome toxin 1 byStaphylococcus aureus. Under good growth conditions, regular absorbency tampons had little effect on bacterial growth and inhibited toxin production two- to four-fold. In contrast, higher absorbency tampons had three different effects: 1) some tampons had no effect on bacterial growth but inhibited toxin production; 2) many tampons inhibited both growth and toxin production; 3) one tampon inhibited growth but increased exotoxin per cell. These effects were independent of degree of saturation of the tampons and were observed at incubation times of six, 12, and 18 hours. In no instance was the production of toxic shock syndrome toxin 1 per milliliter increased in the presence of tampons when compared with control.