Correlations among chemical constituents, cytotoxicities and tissue responses: in the case of natural rubber latex materials.

Natural rubber latex films obtained from 40 different brands of rubber gloves were tested by quantitative chemical analyses, two cytotoxicity tests (agar-diffusion assay using L929 cells and colony assay using V79 cells) and 7-day implantation test in the rabbit muscle. Multiple regression analysis of these data showed that dithiocarbamate accelerators caused the toxicities whereas antioxidants did not. Thickness of inflammatory layer was the most useful parameter to evaluate tissue response among 13 histological parameters investigated. There were good correlations between the cytotoxicity indices and the thickness of inflammatory layer.