|MadSci Network: Botany|
Hi, I am not sure how your duckweeds "met" the washing powder. If the washing powder is dissolved, its little molecules will form little micelles, there are also salt ions in the solution. Once meet plant cell, the salt will distruct the osmotic gradient which is required for cell living, the "little micelles" will destroy the cell membrane. Therefore whatever you are planting, it will be influenced by the chemicals such as wash powder, detergent. On the other hand, the pollution on the earth is very complex, not only some toxic salt, but also sulphite dioxite, chloride gas, nitrate, etc. There are different mechanisms on plant, maybe make distruction on cell membrane, chloroplast or mitochodia, but all destroy the plant's growth. Hope it is still helpful.
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