Transport of oxaliplatin species in water-saturated natural soil

The Dark Side of Platinum Based Cytostatic Drugs: From Detection to Removal

The uncontrolled release of pharmaceutical drugs into the environment raised serious concerns in the last decades as they can potentially exert adverse effects on living organisms even at the low concentrations at which they are typically found. Among them, platinum based cytostatic drugs (Pt CDs) are among the most used drugs in cancer treatments which are administered via intravenous infusion and released partially intact or as transformation products. In this review, the studies on environmental occurrence, transformation, potential ecotoxicity, and possible treatment for the removal of platinum cytostatic compounds are revised. The analysis of the literature highlighted the generally low total platinum concentration values (from a few tens of ng L−1 to a few hundred μg L−1) found in hospital effluents. Additionally, several studies highlighted how hospitals are sources of a minor fraction of the total Pt CDs found in the environment due to the slow excretion rate which is longer than the usual treatment durations. Only some data about the impact of the exposure to low levels of Pt CDs on the health of flora and fauna are present in literature. In some cases, adverse effects have been shown to occur in living organisms, even at low concentrations. Further ecotoxicity data are needed to support or exclude their chronic effects on the ecosystem. Finally, fundamental understanding is required on the platinum drugs removal by MBR, AOPs, technologies, and adsorption.

Transport of platinum-based pharmaceuticals in water-saturated sand and natural soil: Carboplatin and cisplatin species

This study reports the transport characteristics of the pharmaceutical compounds carboplatin and cisplatin, and their respective derivatives, in saturated sand and soil columns. Pharmaceuticals are recognized as emerging pollutants of soil and water resources, but studies of the transport characteristics of organometallic pharmaceuticals in soil-water environments are rare. A recent study of oxaliplatin transport in natural soil raises the question of whether or not its behavior is representative of all Pt-based pharmaceuticals behavior in soil-water systems. To address this question, transport behaviors of carboplatin and cisplatin species were studied individually in packed sand columns under unamended conditions, and in packed soil columns under unamended and acetate-amended conditions. In contrast to oxaliplatin, carboplatin species exhibited very low affinity to both sand and soil surfaces: the retention of injected carboplatin was 3% and <6% for sand and soil, respectively. The affinity to soil was practically the same under the different redox conditions. The affinity of carboplatin to sand and soil surfaces was much smaller than the reported oxaliplatin affinity and the values reported in the literature. Cisplatin exhibited transport behavior similar to that of oxaliplatin in soil, including mild sensitivity to redox conditions (e.g., higher retention under acetate-amended conditions), overall exhibiting retention of 64-70% of the injected species. However, cisplatin also exhibited a similar retention in sand (retention of 45-53%), unlike the cases of carboplatin and oxaliplatin. The results indicate that similarly structured pharmaceuticals can exhibit very different transport characteristic in natural soil-water environments, and should therefore be studied and assessed individually.