Phosphate is certainly no concern. Phthalic acid on the other hand… not just that phthalates (esters of phthalic acid) have a bad reputation but there are alternatives such as malic, citric, or succinic acid paired with a strong base such as NaOH or KOH

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Dear Pharma, thank you so much for your answer! I will check on these accids ::smiley: