Identification of Knowledge Gaps Regarding Healthcare Workers' Exposure to Antineoplastic Drugs: Review of Literature, North America versus Europe

Initial assessment of multi-compound antineoplastic drug surface contamination in Argentinean healthcare centers: Insights into occupational exposures in South America

INTRODUCTION

Antineoplastic drug contamination can result in severe health effects for healthcare workers exposed to them. Despite the worldwide growing concern regarding these drugs and sustained monitoring efforts in developed countries, there is almost no data about surface contamination levels in Argentina, in particular, and South America, in general.

METHODS

Antineoplastic drug contamination was measured in three Argentinean public hospitals (pharmacy and daycare center areas) by surface wiping and liquid chromatography coupled with tandem mass spectrometry.

RESULTS AND DISCUSSION

Eleven drugs were detected, in 51 of 58 sampled surfaces, in variable concentrations from 0.00064 to 7.3 ng cm^-2, with cyclophosphamide, gemcitabine, and paclitaxel as the most prevalent drugs. This highly variable antineoplastic distribution reflects differences in facility layout, number of patients, antineoplastic drug use, etc., at each hospital. Values exceeding the 1 ng cm^-2 threshold were detected in 13 surfaces of the two hospitals handling the largest amounts of antineoplastic drugs. The cyclophosphamide 75th percentile averaged 0.030 ng cm^-2 comparable to the high values reported more than 10 years ago for developed countries, emphasizing the potential of reducing antineoplastic contamination by implementing routine monitoring and improved cleaning and handling procedures.

CONCLUSION

This study is the first survey of multi-compound surface antineoplastic contamination in Argentinean (and South American) hospitals, providing a baseline against which future studies can be compared. Widespread antineoplastic contamination has been detected on numerous surfaces, with concentrations surpassing suggested threshold exposure levels (1 ng cm^-1) for some surfaces in two of the sampled hospitals.

Design of Analytical Method Validation Protocol Evaluating Environmental Monitoring of AND Contamination on Surfaces Based on Cleaning Validation Procedures: A Multi Component RP-UHPLC Method

Environmental monitoring of anti-neoplastic drug (AND) residues in workplaces is crucial to limit exposure to workers who handle with them. Although wipe sampling is the most appropriate methodology to evaluate the risk, conflicting results are also reported due to the lack of standardized and validated procedures. In this study, procedures for surface contamination of ANDs in workplaces are presented, with a focus on sampling, sample preparation and instrumentation. The analytical method validation parameters are designed to comply with requirements of The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q7 Good Manufacturing Practice (GMP) for active pharmaceutical ingredients. Additionally, the study provides a simple, specific, rapid and multi-component analytical method to evaluate seven ANDs that are Gefitinib, Imatinib, Dasatinib, Axitinib, Erlotinib, Nilotinib and Sorafenib at very low concentration levels, simultaneously. Quantitative, precise and reproducible results obtained from the study show that environmental monitoring procedure and analytical method validation protocol presented in the study can be used to reduce and monitor occupational exposure risk to ANDs in wokplaces.

Exposure to Antineoplastic Drugs in Occupational Settings: A Systematic Review of Biological Monitoring Data

The high toxicity of antineoplastic drugs (ADs) makes them dangerous not only for patients, but also for exposed workers. Therefore, the aim of this review was to provide an updated overview of the biological monitoring of occupational AD exposure in order to extrapolate information useful to improve risk assessment and management strategies in workplaces. Several studies demonstrated that remarkable portions of healthcare workers may have traces of these substances or their metabolites in biological fluids, although with some conflicting results. Nurses, directly engaged in AD handling, were the occupational category at higher risk of contamination, although, in some cases, personnel not involved in AD-related tasks also showed quantifiable internal doses. Overall, further research carried out on greater sample sizes appears necessary to gain deeper insight into the variability retrieved in the reported results. This may be important to understand the impact of the extent of ADs use, different handling, procedures, and cleaning practices, spill occurrence, training of the workforce, as well as the adoption of adequate collective and personal protective equipment in affecting the occupational exposure levels. This may support the achievement of the greatest clinical efficiency of such therapies while assuring the health and safety of involved workers.

Spatial and Temporal Variability in Antineoplastic Drug Surface Contamination in Cancer Care Centers in Alberta and Minnesota

The health risks of exposure to antineoplastic drugs (ADs) are well established, and healthcare professionals can be exposed while caring for cancer patients receiving AD therapy. Studies conducted worldwide over the past two decades indicate continuing widespread surface contamination by ADs. No occupational exposure limits have been established for ADs, but concerns over exposures have led to the development of guidelines, such as United States Pharmacopeia (USP) General Chapter <800> Hazardous Drugs-Handling in Healthcare. While recommending regular surveillance for surface contamination by ADs these guidelines do not provide guidance on sampling strategies. Better characterization of spatial and temporal variability of multidrug contamination would help to inform such strategies. We conducted surface-wipe monitoring of nine cancer care centers in Alberta, Canada and Minnesota, USA, with each center sampled eight times over a 12-month period. Twenty surfaces from within pharmacy and drug administration areas were sampled, and 11 drugs were analyzed from each wipe sample. Exposure data were highly left-censored which restricted data analysis; we examined prevalence of samples above limit of detection (LOD), and used the 90th percentile of the exposure distribution as a measure of level of contamination. We collected 1984 wipe samples over a total of 75 sampling days resulting in 21 824 observations. Forty-five percent of wipe samples detected at least one drug above the LOD, but only three of the drugs had more than 10% of observations above the LOD: gemcitabine (GEM) (24%), cyclophosphamide (CP) (16%), and paclitaxel (13%). Of 741 wipe samples with at least one drug above LOD, 60% had a single drug above LOD, 19% had two drugs, and 21% had three drugs or more; the maximum number of drugs found above LOD on one wipe was 8. Surfaces in the compounding area of the pharmacy and in the patient area showed the highest prevalence of samples above the LOD, including the compounding work surface, drug fridge handle, clean room cart, passthrough tray, and hazardous drug room temperature storage, the IV pump keypad, patient washroom toilet handle, patient washroom door handle, nurses' storage shelf/tray, and patient side table. Over the course of the study, both 90th percentiles and prevalence above LOD varied without clear temporal patterns, although some centers appeared to show decreasing levels with time. Within centers, the degree of variability was high, with some centers showing changes of two to three orders of magnitude in the 90th percentile of drug concentrations month to month. A clear difference was observed between the six centers located in Alberta and the three in Minnesota, with Minnesota centers having substantially higher percentages of samples above the LOD for CP and GEM. Other factors that were associated with significant variability in exposures were drug compounding volume, size of center, number of patients seen, and age of the center. We hope that demonstrating variability associated with drug, surface, clinic-factors, and time will aid in a better understanding of the nature of AD contamination, and inform improved sampling strategies.

Nurses' internal contamination by antineoplastic drugs in hospital centers: a cross-sectional descriptive study

OBJECTIVE

The aim of this study was to assess internal antineoplastic drugs (ADs) contamination in the nursing staff in French hospital centers, using highly sensitive analytical methods.

METHODS

This cross-sectional study included nurses practicing in care departments where at least one of the five ADs studied was handled (5-fluorouracil, cyclophosphamide, doxorubicin, ifosfamide, methotrexate). The nurses study participation lasted 24 h including collection of three urine samples and one self-questionnaire. All urine samples were assayed by ultra-high-performance liquid chromatography-tandem mass spectrometry methods with very low value of the lower limit of quantification (LLOQ).

RESULTS

74 nurses were included, 222 urine samples and 74 self-questionnaires were collected; 1092 urine assays were performed. The percentage of nurses with internal AD contamination was 60.8% and low levels of urinary concentrations were measured. Regarding nurses with internal contamination (n = 45), 42.2% presented internal contamination by methotrexate, 37.8% by cyclophosphamide, 33.3% by ifosfamide, 17.8% by 5-fluorouracil metabolite and 6.7% by doxorubicine. Among the positive assays, 17.9% (n = 26/145) were not explained by exposure data from the self-questionnaire but this could be due to the skin contact of nurses with contaminated work surfaces.

CONCLUSIONS

This study reported high percentage of nurses with internal ADs contamination. The low LLOQ values of the used analytical methods, allowed the detection of ADs that would not have been detected with the current published methods: the percentage of contamination would have been 17.6% instead of the 60.8% reported here. Pending toxicological reference values, urine ADs concentrations should be reduced as low as reasonably achievable (ALARA principle).

The efficiency of antineoplastic drug contamination removal by widely used disinfectants-laboratory and hospital studies

OBJECTIVE

Antineoplastic drugs (ADs) pose risks to healthcare staff. Surface disinfectants are used in hospitals to prevent microbial contamination but the efficiency of disinfectants to degrade ADs is not known. We studied nine disinfectants on ten ADs in the standardized laboratory and realistic in situ hospital conditions.

METHODS

A survey in 43 hospitals prioritized nine most commonly used disinfections based on different ingredients. These were tested on inert stainless steel and in situ on contaminated hospital flooring. The effects against ten ADs were studied by LC-MS/MS (Cyclophosphamide CP; Ifosfamide IF; Capecitabine CAP; Sunitinib SUN; Methotrexate MET; Doxorubicin DOX; Irinotecan IRI; Paclitaxel PX; 5-Fluorouracil FU) and ICP-MS (Pt as a marker of platinum-based ADs).

RESULTS

Monitoring of the floor contamination in 26 hospitals showed that the most contaminated are the outpatient clinics that suffer from a large turnover of staff and patients and have limited preventive measures. The most frequent ADs were Pt, PX, FU and CP with maxima exceeding the recommended 1 ng/cm² limit by up to 140 times. IRI, FU, MET, DOX and SUN were efficiently removed by hydrolysis in clean water and present thus lower occupational risk. Disinfectants based on hydrogen peroxide were efficient against PX and FU (> 70% degradation) but less against other ADs, such as carcinogenic CP or IF, IRI and CAP. The most efficient were the active chlorine and peracetic acid-based products, which however release irritating toxic vapors. The innovative in situ testing of ADs previously accumulated in hospital flooring showed highly problematic removal of carcinogenic CP and showed that alcohol-based disinfectants may mobilize persistent ADs contamination from deeper floor layers.

CONCLUSION

Agents based on hydrogen peroxide, peracetic acid, quaternary ammonium salts, glutaraldehyde, glucoprotamine or detergents can be recommended for daily use for both disinfection and AD decontamination. However, they have variable efficiencies and should be supplemented by periodic use of strong chlorine-based disinfectants efficient also against the carcinogenic and persistent CP.

Extent of Primary DNA Damage Measured by the Comet Assay in Health Professionals Exposed to Antineoplastic Drugs: A Systematic Review and Meta-Analysis

BACKGROUND

Antineoplastic drugs (ANDs) are a broad group of chemicals showing, at the same time, carcinogenic effects. The potential, albeit true, risk of side effects cannot be accepted, especially if resulting from occupational exposure. The aim of this study was to evaluate the association between occupational exposure to ANDs and the extent of primary DNA damage in health professionals.

METHODS

A systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/Medline, Web of Science, and Scopus were used to perform the literature search. The databases were examined in July 2019. Sub-group, moderator, and cumulative analyses were conducted. The trim and fill method was used in the case of potential publication bias.

RESULTS

Twenty studies were included in the qualitative analysis, and 19 in quantitative evaluation. The pooled effect size was 1.27 [(95% confidence interval (CI) = 0.66-1.88), p = 0.000] based on 1569 subjects. The moderator analysis by duration of exposure showed a positive association between duration of exposure and primary DNA damage.

CONCLUSIONS

This systematic review clearly shows a significant association between occupational exposure to ANDs and the extent of primary DNA damage in health professionals. Considering these results, health professionals should be warned against this potential occupational risk.

Guidelines for safe handling of hazardous drugs: A systematic review

Objective

To review the scientific literature related to the safe handling of hazardous drugs (HDs).

Method

Critical analysis of works retrieved from MEDLINE, the Cochrane Library, Scopus, CINHAL, Web of Science and LILACS using the terms "Hazardous Substances", "Antineoplastic Agents" and "Cytostatic Agents", applying "Humans" and "Guidelines" as filters. Date of search: January 2017.

Results

In total, 1100 references were retrieved, and from those, 61 documents were selected based on the inclusion and exclusion criteria: 24 (39.3%) documents related to recommendations about HDs; 27 (44.3%) about antineoplastic agents, and 10 (33.3%) about other types of substances (monoclonal antibodies, gene medicine and other chemical and biological agents). In 14 (23.3%) guides, all the stages in the manipulation process involving a risk due to exposure were considered. Only one guide addressed all stages of the handling process of HDs (including stages with and without the risk of exposure). The most described stages were drug preparation (41 guides, 67.2%), staff training and/or patient education (38 guides, 62.3%), and administration (37 guides, 60.7%). No standardized informatics system was found that ensured quality management, traceability and minimization of the risks associated with these drugs.

Conclusions

Most of the analysed guidelines limit their recommendations to the manipulation of antineoplastics. The most frequently described activities were preparation, training, and administration. It would be convenient to apply ICTs (Information and Communications Technologies) to manage processes involving HDs in a more complete and simpler fashion.

Surface contamination of counting tools after mock dispensing of cyclophosphamide in a simulated outpatient pharmacy

PURPOSE

The primary aim was to determine if dispensing of cyclophosphamide tablets resulted in accumulated residue on pharmacy counting tools during a simulated outpatient dispensing process. Secondary objectives included determining if cyclophosphamide contamination exceeded a defined threshold level of 1 ng/cm² and if a larger number of prescriptions dispensed resulted in increased contamination.

METHODS

Mock prescriptions of 40 cyclophosphamide 50 mg tablets were counted on clean trays in three scenarios using a simulated outpatient pharmacy after assaying five cleaned trays as controls. The three scenarios consisted of five simulated dispensings of one, three, or six prescriptions dispensed per scenario. Wipe samples of trays and spatulas were collected and assayed for all trays, including the five clean trays used as controls. Contamination was defined as an assayed cyclophosphamide level at or above 0.001 ng/cm² and levels above 1 ng/cm² were considered sufficient to cause risk of human uptake. Mean contamination for each scenario was calculated and compared using one-way analysis of variance. P-values of < 0.05 implied significance.

RESULTS

Mean cyclophosphamide contamination on trays used to count one, three, and six cyclophosphamide prescriptions was 0.51 ± 0.10 (p=0.0003), 1.02 ± 0.10 (p < 0.0001), and 1.82 ± 0.10 ng/cm² (p < 0.0001), respectively. Control trays did not show detectable cyclophosphamide contamination. Increasing the number of prescriptions dispensed from 1 to 3, 1 to 6, and 3 to 6 counts increased contamination by 0.51 ± 0.15 (p = 0.0140), 1.31 + 0.15 (p < 0.0001), and 0.80 ± 0.15 ng/cm² (p = 0.0004), respectively.

CONCLUSION

Dispensing one or more prescriptions of 40 cyclophosphamide 50 mg tablets contaminates pharmacy counting tools, and an increased number of prescriptions dispensed correlates with increased level of contamination. Counting out three or more prescriptions leads to trays having contamination that surpasses the threshold at which worker exposure may be increased. Pharmacies should consider devoting a separate tray to cyclophosphamide tablets, as cross-contamination could occur with other drugs and the efficacy of decontamination methods is unclear. Employee exposure could be minimized with the use of personal protective equipment, environmental controls, and cleaning trays between uses. Future investigation should assess the extent of drug powder dispersion, the effects of various cleaning methods, and the potential extent of contamination with different oral cytotoxic drugs.

Antineoplastic drug residues inside homes of chemotherapy patients

Chemotherapy treatment of cancer patients has shifted from inpatient to outpatient administration. Thus, family members are potentially exposed to cytotoxic drug residues from patients' excretions inside their homes. The study's aim was to evaluate the surface contamination and the potential uptake of antineoplastic drug residues by family members at home of chemotherapy patients. Overall, 265 wipe samples from 13 homes were taken at two times after chemotherapy from different surfaces (toilet, bathroom, kitchen). 62 urine samples were collected from patients and family members on three days. Samples were analyzed for cyclophosphamide, 5-fluorouracil (urine: FBAL) and platinum (as marker for cis-, carbo- and oxaliplatin). Substantial contamination was found on every surface type (PT: 0.02-42.5pg/cm², 5-FU: ND-98.3pg/cm², CP: ND-283.3pg/cm²) with highest concentrations on toilet and bathroom surfaces. While patients' urinary drug concentrations often were elevated for more than 48h after administration, no drug residues were detectable in the family members' urine. This study provided an insight in the exposure situation against antineoplastic drug residues at home of chemotherapy patients. As contamination could be found on various surfaces adequate hygienic and protective measures are necessary to minimize the exposure risk for cohabitants.

A review of surface wipe sampling compared to biologic monitoring for occupational exposure to antineoplastic drugs

The potential for adverse health effects from occupational exposure to antineoplastic drugs (AD) is well known. Control measures recommended by the NIOSH Alert ^[3] include medical and biologic monitoring, and environmental monitoring where available. At present no guidelines or published best practices exist to guide EHS managers on how to carry out this biologic or environmental monitoring. Studies investigating surface wipe sampling for AD have been numerous in the past decade, but very limited research exists to correlate surface contamination with actual absorption by pharmacists and nurses. This article reviews the studies with concurrent surface wipe sampling and urine monitoring for the same AD, and tests their correlation. Methodologic limitations are reviewed. Twenty-one studies were identified that concurrently measured surface contamination by AD by wipe sampling and AD absorption by urine monitoring. Two studies directly evaluated the AD by wipe sampling and urine levels and neither found a statistically significant correlation. Six studies reported a decrease in both surface and urine levels following interventions to reduce contamination or exposure. Only one study directly evaluated the personal protective equipment and handling techniques employed by the studied workers, which can be viewed as a major confounder of absorption. While no statistically significant correlation was found between wipe sampling and urine monitoring for AD, decreases in urine and wipe levels following interventions to reduce exposure were noted. Limitations in the data and recommendations for future research are reviewed.