Catherine Bach got a speck of flying glass in her eye when the glass shattered on the second mirror after Sorrel broke it himself while swatting at the fly with the folded newspaper; she states this in the bonus material. She does not mention having suffered any severe or permanent injury, and her eyes look fine in subsequent movies/photos, so she was apparently okay afterwards, but you can clearly see her dabbing at her face immediately after the mirror breaks.
Production Code: #167125. Filming Dates: October 13-22, 1980.