Phosphoric acid is originally an essential ingredient found in the body, and is also included in fertilizers, so there is no problem for those who promote sustainability.
This is an external link, but below is a summary of the scientific basis for this ▼
〇 Functions of phosphorus and daily intake/Foundation for the Promotion of Longevity Science ``The adult body contains up to 800g of phosphorus, and phosphorus itself is not poisonous.''
https://www.tyojyu.or.jp/net/kenkou-tyoju/eiyouso/mineral-p.html
〇Three elements of fertilizer - Functions of nitrogen, phosphoric acid, and potassium/NHK text "Nutritious substances that plants must ingest in order to survive"
http://textview.jp/post/hobby/29661
Related questions:
What is the environmental impact of "products containing phosphoric acid"?