Chemical Decontamination of Hazardous Drugs: A Comparison of Solution Performances

Canadian monitoring program of the surface contamination with 11 antineoplastic drugs in 124 centers

INTRODUCTION

Occupational exposure to antineoplastic drugs can lead to long-term adverse effects on workers' health. A reproducible Canadian surface monitoring program was established in 2010. The objective was to describe contamination with 11 antineoplastic drugs measured on 12 surfaces among hospitals participating in this annual monitoring program.

METHODS

Each hospital sampled six standardized sites in oncology pharmacies and six in outpatient clinics. Ultra-performance liquid chromatography coupled with tandem mass spectrometry was used for cyclophosphamide, docetaxel, doxorubicin, etoposide, 5-fluorouracil, gemcitabine, irinotecan, methotrexate, paclitaxel, and vinorelbine. Platinum-based drugs were analyzed by inductively coupled plasma mass spectrometry; this excludes inorganic platinum from the environment. Hospitals filled out an online questionnaire about their practices; a Kolmogorov-Smirnov test was used for some practices.

RESULTS

One hundred and twenty-four Canadian hospitals participated. Cyclophosphamide (405/1445, 28%), gemcitabine (347/1445, 24%), and platinum (71/756, 9%) were the most frequent. The 90th percentile of surface concentration was 0.01 ng/cm² for cyclophosphamide and 0.003 ng/cm² for gemcitabine. Centers that prepared 5000 or more antineoplastic per year had higher concentrations of cyclophosphamide and gemcitabine on their surfaces (p  =  0.0001). Almost half maintained a hazardous drugs committee (46/119, 39%), but this did not influence the cyclophosphamide contamination (p  =  0.051). Hazardous drugs training was more frequent for oncology pharmacy and nursing staff than for hygiene and sanitation staff.

CONCLUSIONS

This monitoring program allowed centers to benchmark their contamination with pragmatic contamination thresholds derived from the Canadian 90th percentiles. Regular participation and local hazardous drug committee involvement provide an opportunity to review practices, identify risk areas, and refresh training.

Studies on the optimization of decontamination protocol for surfaces contaminated with cytotoxic drugs in PIVAS

PURPOSE

The goal of this study was to create a cleaning procedure by comparing the performance of six different cleaning methods on the surfaces in pharmacy intravenous admixture service (PIVAS) work area.

METHOD

A stainless steel plate was simulating contaminated by gemcitabine, cyclophosphamide, epirubicin, etoposide, and paclitaxel, which was then dried and cleaned by per current cleaning protocols. The residues were collected and quantified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Based on the most appropriate cleaning protocol, three cleaning variables were optimized: (1) use of dry gauze after cleaning agent application; (2) cleaning paths (inside-out vs. outside-in); (3) cleaning times (once or twice). Best conditions were tested with real samples from a hospital PIVAS.

RESULTS

This 10-2 M sodium dodecyl sulfate (SDS) and dry gauze cleaning protocol increases cleaning efficiency as well as saves time. Different from the traditional cleaning manner, we found that cleaning from outside to inside can not only improve the cleaning efficiency but also overcome the uneven distribution of drug residues caused by cleaning action. When simulating contamination at a high dose (4 mg/mL) level, it was found that the decontamination efficacy increased with repeating one more time.

CONCLUSION

The 10-2 M SDS and dry gauze cleaning protocol could obtain the best cleaning effect. The success of cytotoxic drug decontamination is determined not only by the cleaning solution, but also by the cleaning route and frequency. Compared with the traditional cleaning manner, there was a significant reduction in the contamination levels in the PIVAS work area after the cleaning protocol with 10-2 M SDS and dry gauze.

Study on the Use of Ozone Water as a Chemical Decontamination Agent for Antineoplastic Drugs in Clinical Settings

The exposure of healthcare workers to antineoplastic drugs in hospitals has been recognized to be harmful. To minimize the risk of exposure, the removal of these drugs from work environments, such as compounding facilities, has been recommended. In our previous paper, the degradation and inactivation efficacy of ozone water, which is being introduced into Japanese hospitals as a chemical decontamination agent, was reported for its effects on typical antineoplastic drugs (gemcitabine, irinotecan, paclitaxel). This article aims to further investigate the efficacy of ozone water for eight antineoplastic drugs to clarify its application limitations. A small amount (medicinal ingredient: typically ca. 1.5 μmol) of formulation containing 5-fluorouracil, pemetrexed, cisplatin, oxaliplatin, cyclophosphamide, ifosfamide, doxorubicin, or docetaxel was mixed with 50 mL of ozone water (~8 mg/L), and the resulting solutions were analyzed by high-performance liquid chromatography over time to observe the degradation. Consequently, the ozonation was overall effective for the degradation of the drugs, however this varied depending on the chemical structures of the drugs and additives in their formulations. In addition, after the parent drugs were completely degraded by the ozonation, the degradation mixtures were subjected to 1H nuclear magnetic resonance spectroscopy and evaluated for mutagenicity against Salmonella typhimurium strains and cytotoxicity against human cancer cells. The degradation mixtures of cisplatin and ifosfamide were mutagenic while those of the other drugs were non-mutagenic. Further, the ozonation resulted in clear decreases of cytotoxicity for 5-fluorouracil, oxaliplatin, and doxorubicin, but increases of cytotoxicity for pemetrexed, cisplatin, cyclophosphamide, and ifosfamide. These results suggest that the ozone water should be restrictedly used according to the situation of contamination in clinical settings because the ozonation enhances toxicity depending on the drug even if degradation is achieved.

Impact of low- and high-risk operators handling irinotecan on the blood contamination of health care workers in oncology day care units

INTRODUCTION

Health care workers handling antineoplastic drugs (ADs) are at risk of mutagenicity and adverse reproductive effects. Despite protective equipment and AD handling guidelines, AD levels are still detected in caregivers in oncology units. This study attempted to assess blood contamination by irinotecan and its metabolites in all health care workers in oncology day hospital units according to activities specific to each employment category.

METHODS

The study was performed at two different hospitals: a university hospital and a comprehensive cancer centre. Forty-four participants were categorized according to their daily activity as a high-risk operator (29 nurses/ward aides and 5 cleaning staff) and a low-risk operator (7 doctors and 3 secretaries). The collected blood samples were subjected to UHPLC-MS/MS. The plasma and red blood cell (RBC) levels of irinotecan and its metabolites (SN-38; APC) were determined using a validated analytical method detection test.

RESULTS

Two hundred sixty-four assay results were collected (132 plasma results and 132 RBC results). The comparison between low- and high-risk operator-contaminated workers was not significant (18.33% positive results in low-risk operators vs. 25.98% positive results in high-risk operators; P = 0.22). This homogeneity showed overall contamination within the unit. Positive results were obtained in 21.43% of physicians, 11.11% of secretaries, 25.86% of nurses/ward aides and 26.67% of cleaning staff. These results could be explained by the lack or failure of personal and collective protective equipment. A lack of protection and inadequate decontamination procedures can result in surface contamination.

CONCLUSIONS

This study evaluated blood contamination with irinotecan and its metabolites in health care workers from day hospital care units. Among the 24.24% of contaminations observed in care units, the difference between low- and high-risk operator contamination was not significant (P = 0.22). The impact on blood contamination found is the same between low- and high-risk caregivers. This implies that the protective precautions associated with the handling of anticancer drugs must therefore be followed by all staff, including those believed to be at low risk of exposure.

Efficacy of two intensive decontamination protocols and their effects after 30 days on environmental contamination by cyclophosphamide

Objectives

To evaluate the efficacy of two decontamination protocols on cyclophosphamide surface contamination and to explore its lasting effect 30 days later.

Methods

All sampling sites that were systematically contaminated with cyclophosphamide in 2017–2020 were included, from a convenience sample of centers. The first decontamination protocol consisted of four steps, each with 20 mL and a Wypall® wipe: detergent, sodium hypochlorite 2%, isopropyl alcohol 70% and water. The second decontamination protocol consisted of eight steps, each with 15 mL and a Micronsolo® microfibre wipe: detergent, sodium hypochlorite 2%, isopropyl alcohol 70%, water and then a second round with each of the four products. A first sampling was done at the end of a regular working day (T0), a second immediately following decontamination (T1) and a third 30 days later (T2) after regular operations. Cyclophosphamide was quantified by ultra-performance liquid chromatography – tandem mass spectrometry (limit of detection 0.001 ng/cm2).

Results

Seventeen sampling sites were included: six biological safety cabinet (BSC) front grilles, eight floors in front of BSCs and three cyclophosphamide storage shelves. The second protocol was more effective; however they both failed to completely remove all cyclophosphamide traces. BSCs and floors were found to be contaminated again 30 days later, at similar concentrations than at T0. A lasting effect was observed on the cyclophosphamide storage shelves that were less prone to be contaminated again.

Conclusions

Periodic decontamination with many cleaning steps is necessary on all surfaces, including those less frequently contaminated. Regular surface monitoring identifies systematically contaminated areas.

Evaluation of decontamination efficacy of four antineoplastics (ifosfamide, 5-fluorouracil, irinotecan, and methotrexate) after deliberate contamination

The main objective was to determine the decontamination efficacy of quaternary ammonium, 0.1% sodium hypochlorite, and water after deliberate contamination with four antineoplastics (ifosfamide, 5-fluorouracil, irinotecan, methotrexate). A stainless-steel surface was deliberately contaminated with ifosfamide (15 µg), 5-fluorouracil (10 µg), irinotecan (1 µg), and methotrexate (1 µg). First, a single decontamination step with either water, quaternary ammonium, or 0.1% sodium hypochlorite was tested. Then, the effect of up to four successive decontamination steps with either quaternary ammonium or 0.1% sodium hypochlorite was tested. Commercial wipes consisting of two layers of non-woven microfibers with an inner layer of highly absorbent viscose fibers were used. Triplicate surface samples were obtained and tested by ultra-performance liquid chromatography tandem mass spectrometry. The limits of detection were 0.004 ng/cm² for ifosfamide, 0.040 ng/cm² for 5-fluorouracil, 0.003 ng/cm² for irinotecan, and 0.002 ng/cm² for methotrexate. After a single decontamination step, the 0.1% sodium hypochlorite eliminated 100% of contamination with 5-fluorouracil, irinotecan, and methotrexate and 99.6 ± 0.5% of ifosfamide contamination. Quaternary ammonium and water also removed 100% of the 5-fluorouracil, and 99.5% to 99.9% of the other three antineoplastics. For ifosfamide, irinotecan, and methotrexate, the decontamination efficacy increased with successive decontamination steps with quaternary ammonium. 5-fluorouracil was undetectable after a single decontamination step. Methotrexate was the only drug for which decontamination efficacy was less than 100% after four decontamination steps. 100% decontamination efficacy was achieved from the decontamination step with 0.1% sodium hypochlorite for 5-fluorouracil, irinotecan, and methotrexate. For ifosfamide, 100% efficacy was achieved only after the third decontamination step. It was possible to make all traces of antineoplastic undetectable after deliberate contamination with 5-fluorouracil, irinotecan, and methotrexate with a 0.1% chlorine solution; up to three decontamination steps were needed to make ifosfamide undetectable. Water or quaternary ammonium removed more than 99.5% of deliberate contamination. In several scenarios, it was necessary to repeat the decontamination to eliminate residual traces. More work is needed to identify the optimal decontamination approach for all of the antineoplastic drugs used.

Efficiency of four solutions in removing 23 conventional antineoplastic drugs from contaminated surfaces

BACKGROUND

Residual contamination by intravenous conventional antineoplastic drugs (ICAD) is still a daily issue in hospital facilities. This study aimed to compare the efficiency (EffQ) of 4 different solutions to remove 23 widely used ICADs from surfaces.

METHOD AND FINDINGS

A solution containing 23 ICADs (4 alkylating agents, 8 antimetabolites, 2 topo-I inhibitors, 6 topo-II inhibitors and 3 spindle poisons) was spread over 100 cm2 stainless steel. After drying, decontamination was carried out using 10×10 cm wipes moistened with 300 μL of one of the following solutions: 70% isopropanol (S1); ethanol-hydrogen peroxide 91.6-50.0 mg/g (S2); 10-2 M sodium dodecyl sulphate/isopropanol 80/20 (S3) or 0.5% sodium hypochlorite (S4). Six tests were performed for each decontamination solution. Two modalities were tested: a single wipe motion from top to bottom or vigorous wiping (n = 6 for each modality). Residual contamination was measured with a validated liquid chromatography with tandem mass spectrometry detection method. Solution efficiency (in %) was computed as follows: EffQ = 1-(quantity after decontamination/quantity before decontamination), as median (min-max) for the 23 ICADs. The overall decontamination efficiency (EffQ) of the 4 solutions was compared by a Kruskall-Wallis test. Decontamination modalities were compared for each solution and per ICAD with a Mann-Whitney test (p<0.05). EffQ were significantly different from one solution to the next for single wipe motion decontamination: 79.9% (69.3-100), 86.5% (13.0-100), 85.4% (56.5-100) and 100% (52.9-100) for S1, S2, S3 and S4 (p<0.0001), respectively. Differences were also significant for vigorous decontamination: EffQ of 84.3% (66.0-100), 92.3% (68.7-100), 99.6% (84.8-100) and 100% (82.9-100) for S1, S2, S3 and S4, respectively (p<0.0001). Generally, vigorous decontamination increased EffQ for all tested solutions and more significantly for the surfactant.

CONCLUSION

Decontamination efficiency depended on the solution used but also on the application modality. An SDS admixture seems to be a good alternative to sodium hypochlorite, notably after vigorous chemical decontamination with no hazard either to materials or workers.