Can kinoki detox pads make you nauseous or cause harm?

Yes, but it depends on the chemicals that are used. The skin allows for trans-dermal absorption of practically any solution into the blood - and somewhat directly. Because this bypasses digestive break-down, it is wise to be even more careful about what is placed upon the skin than into the mouth. While there are certain chelating (heavy metal detox) agents that can be administered by skin absorption (in particular DMSO and possibly EDTA), it is very unlikely that any commercial retail products actually contain these things. It is also very likely that there could be serious impurity problems with such products, for they are practically unregulated. In other Words, you are unlikely to find a detox pad that is either safe or effective. For most people, all that is needed for basic detoxification is changes in the diet (like green vegetables), adding selenium supplements, the amino acid NAC, and perhaps some cilantro. While there are turn-key products for this sort of thing, there is always an issue of trust with the respective companies. Doing it yourself is better, because if you cannot take ownership of your health then detoxification not going to do you good for long anyway. You must take the time to actually learn about what you are doing, and why you are doing it, because a little bit of knowledge is a dangerous thing.