Occupational exposure to antineoplastic drugs and the development of tailor-made risk control strategies in South African oncology pharmacies

Abstract

Background Occupational exposure to antineoplastic drugs (ADs) poses significant health risks, with oncology pharmacy personnel in South Africa potentially experiencing higher and more exposure than their international counterparts due to insufficient regulatory frameworks and poor compliance with guidelines. Given the anticipated rise in cancer incidence in sub-Saharan Africa by 2030, addressing these occupational risks has become increasingly critical. Current South African guidelines exhibit notable inadequacies and contradictions with key legislative documents, and empirical evidence on workplace and biological contamination within local oncology pharmacies remains absent. The aim of this research was to assess occupational exposure risks to ADs among oncology pharmacy personnel in South Africa and, subsequently, develop tailored risk control strategies (TMRCS). The study objectives were: 1. To evaluate the adherence of South African oncology pharmacy personnel to national and international guidelines via observational surveys. 2. To identify shortfalls through a comparative analysis of local guidelines, the Good Pharmacy Practice (GPP) and Independent Clinical Oncology Network (ICON) guidelines, against international benchmarks. 3. To investigate demographic and occupational factors influencing workplace and biological contamination, using surface wipe sampling, biological monitoring (urine analysis), and the semi-quantitative DeRmal Exposure Assessment Method (DREAM). 4. To develop TMRCS based on identified compliance shortcomings and AD contamination as measured in the participating oncology pharmacies. xi Methods Oncology pharmacies were recruited for participation in the study, through the South African Society of Oncology Pharmacists (SASOPh) from March to September 2023. The pharmacies originated from two service providers (SPs): SP1 and SP2. Study methods included: • Observational cross-sectional surveys using a 43-item compliance checklist derived from international guidelines. • Comparative document analysis evaluating GPP and ICON standards against the International Society of Oncology Pharmacy Practitioners (ISOPP) ‘Safe handling of cytotoxics guideline and the European Society of Oncology Pharmacy (ESOP) ‘QuaPos’ (Quality Standard for the Oncology Pharmacy Service) across 10 safety domains. • Surface wipe sampling for nine ADs pre- and post-decontamination, and urine sampling to determine occupational exposure to the same ADs. • Synthesis of findings into practical, evidence-based interventions, using a structured performance table. In these studies, oncology pharmacy practices were systematically evaluated by converting checklist scores to compliance percentages and comparing them against international standards, while HPLC-MS/MS quantified antineoplastic drug contamination from surface wipes and urine. Descriptive and inferential statistics—including regression imputation, t-tests, Wilcoxon tests, and Spearman correlations—assessed decontamination efficacy and exposure risk associations. Results Recruitment proved challenging, resulting in the enrolment of only six pharmacies (three each in Gauteng and Western Cape provinces). Six pharmacy personnel participated (mean age: 51.1 ± 6.7 years; mean employment duration: 11.7 ± 5.7 years; mean daily AD exposure: 6.0 ± 1.8 hours). Observational surveys indicated checklist compliance variability of 33.1%–79.3% within the 10 domains used in a previous study, with notable deficiencies in engineering controls and medical monitoring. Pharmacies within service provider 2 (SP 2) exhibited better xii adherence, particularly concerning personal protective equipment (PPE) and administrative practices. The document analysis revealed that there are substantial inadequacies within the GPP guidelines compared to the more comprehensive ICON, ISOPP, and QuaPos standards. Workplace sampling confirmed widespread AD contamination, with higher contamination in SP1 facilities. Antineoplastic concentrations post-decontamination showed only a modest 17.4% reduction. Biological monitoring detected cyclophosphamide and ifosphamide in urine samples from SP1 personnel, confirming occupational exposure. Based on the findings from the first three objectives, interventions to reduce exposure to ADs were identified. These prioritised improved decontamination protocols, mandatory PPE usage, and comprehensive staff training. Closed-system transfer devices (CSTDs) were identified as beneficial adjuncts rather than standalone measures. Conclusion The findings from this research underline the critical need for improved regulatory standards and compliance enforcement within South African oncology pharmacies. Enhanced guidelines, compulsory PPE protocols, regular training, and effective decontamination methods are essential to mitigate occupational exposure. Facilities demonstrating higher compliance with best practices provide practical models for national improvement, informing policy advocacy for robust occupational health safeguards and patient safety assurances.