Quinolinic acid (QUIN), an occasional metabolite of the amino acid tryptophan, is found at 300% ordinary levels in the CSF of suicide attempters. Phthalates, a common component of plastics, can inhibit the enzyme that prevents QUIN's formation.

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Quinolinic acid (QUIN), an occasional metabolite of the amino acid tryptophan, is found at 300% ordinary levels in the CSF of suicide attempters. Phthalates, a common component of plastics, can inhibit the enzyme that prevents QUIN's formation.