Phototransformation of Amlodipine in Aqueous Solution: Toxicity of the Drug and Its Photoproduct on Aquatic Organisms

Marina Dellagreca,Sara Montanaro,Maria Rubino,Lucio Previtera,Maria Rosaria Iesce,Marina Isidori

doi:10.1155/2007/63459

Abstract

The phototransformation of amlodipine in water was investigated under various conditions. A quantum yield ΦS2.2×10−4 and a half-life time t1/2 0.419 days were calculated when the drug in water (10−4 M) was exposed to sunlight. The only photoproduct found was its pyridine derivative. Formation of this product was explained on the basis of a radical cation intermediate. The acute and chronic toxicity of the drug and its photoproduct were evaluated on different organisms of the freshwater chain (Brachionus calyciflorus, Thamnocephalus platyurus, Daphnia magna, Ceriodaphnia dubia). The photoproduct exhibited a stronger toxic potential than the parent drug on the long time for C. dubia.

Highlights

There is a growing literature relating to observation of human pharmaceuticals in the environment [1]
The acute and chronic toxicity of the drug and its photoproduct were evaluated on different organisms of the freshwater chain (Brachionus calyciflorus, Thamnocephalus platyurus, Daphnia magna, Ceriodaphnia dubia)
The European Scientific Committee on toxicity, ecotoxicity and the environment (CSTEE) has proposed in 2001 a draft on the environmental risk assessment of medicinal products, and the need to take into account the drugs and their transformation products is recommended [6]. In this context we have studied the abiotic transformation of some anti-inflammatory drugs in the aquatic environment and we have found that some byproducts are more harmful than the parent compounds [7]

Summary

Introduction

There is a growing literature relating to observation of human pharmaceuticals in the environment [1]. The European Scientific Committee on toxicity, ecotoxicity and the environment (CSTEE) has proposed in 2001 a draft on the environmental risk assessment of medicinal products, and the need to take into account the drugs and their transformation products is recommended [6]. In this context we have studied the abiotic transformation of some anti-inflammatory drugs in the aquatic environment and we have found that some byproducts are more harmful than the parent compounds [7]

Methods

Results

Conclusion