Parabens: These notorious and ubiquitous preservatives are found in nearly every type of cosmetic. Parabens mimic estrogen and are implicated in breast cancer, though no causal relationship has been established. Parabens will show up on labels as benzylparaben, butylparaben, ethylparaben, isobutylparaben, isopropylparaben, methylparaben, heptylparaben and/or propylparaben. Skin Deep Score: 5-6, depending on the paraben.