PPE unmasked: why health-care workers in Australia are inadequately protected against coronavirus

In Victoria, more than 1,100 health-care workers have now been infected with SARS-CoV-2, the coronavirus that causes COVID-19. Some 11% of active cases are workers in the health-care sector. Health-care workers are reported to be among those fighting for life in Victorian intensive care units

Have you got your head in the sand? Respirable crystalline exposures of restorative stonemasons

Restoration stonemasons play a vital role in preserving culturally significant heritage buildings and the majority of culturally significant buildings in Sydney are constructed using Sydney sandstone, with an average silica content of 75%. Stonemasons conducting the close inspection required for precision sandstone grinding restoration works are considered at significant risk of exposure to respirable crystalline silica (RCS). An occupational hygiene survey was conducted to assess the risk of RCS exposure of restoration stonemasons conducting various tasks. Exposure monitoring for respirable dust (RD) and RCS was undertaken and the task of grinding sandstone determined as the highest exposure risk. \u27Spinning\u27 and \u27Chopping out\u27 tasks were identified as \u27high risk\u27 activities with excessive exposures of 4, 6 and 12 mg/m3, well above the workplace exposure standard (WES) of 0.1 mg/m3. Short duration task monitoring was conducted to better evaluate worker exposures and job rotation during the highest risk grinding task was not determined as a suitable control to reduce stonemason exposures. A trial was undertaken using on-tool dust collecting shrouds attached to local exhaust ventilation (LEV) system to evaluate the effectiveness and suitability to grinding tasks, with a 99% exposure reduction achieved. Reducing stonemason exposures below the WES was still not possible for grinding tasks; and numerous control measures were recommended to ensure workers are not exposed to concentrations of RCS likely to cause risk to health. Implementation of a combination of control measures is essential in reducing RCS exposure risk. Controls selected in line with the hierarchy of controls include:- mini enclosures, wet methods of dust suppression, on-tool dust collection shrouds and local exhaust ventilation (LEV); along with appropriate respiratory protection commensurate to exposure and powered air purifying respirators (PAPR) when grinding sandstone. Stonemasons grinding sandstone are considered at high risk of RCS exposure. They were encouraged to participate in equipment trials and evaluate their effectiveness. The more informed the stonemasons became, the more inspired they were to reduce their RCS exposure and integrate small, effective changes during sandstone restoration activities. Utilising knowledge from industry experts was invaluable in ensuring a successful trial, and gaining the confidence of the cohort. Throughout the risk assessment process, the stonemasons increased their knowledge and understanding of RCS

Efficiency of respirator filter media against diesel particulate matter: a comparison study using two diesel particulate sources

Diesel engines have been a mainstay within many industries since the early 1900s. Exposure to diesel particulate matter (DPM) is a major issue in many industrial workplaces given the potential for serious health impacts to exposed workers; including the potential for lung cancer and adverse irritant and cardiovascular effects. Personal respiratory protective devices are an accepted safety measure to mitigate worker exposure against the potentially damaging health impacts of DPM. To be protective, they need to act as effective filters against carbon and other particulates. In Australia, the filtering efficiency of respiratory protective devices is determined by challenging test filter media with aerosolised sodium chloride to determine penetration at designated flow rates. The methodology outlined in AS/NZS1716 (Standards Australia International Ltd and Standards New Zealand 2012. Respiratory protective devices. Sydney/Wellington: SAI Global Limited/Standards New Zealand) does not account for the differences between characteristics of workplace contaminants like DPM and sodium chloride such as structure, composition, and particle size. This study examined filtering efficiency for three commonly used AS/NZS certified respirator filter models, challenging them with two types of diesel emissions; those from a diesel generator and a diesel engine. Penetration through the filter media of elemental carbon (EC), total carbon (TC), and total suspended particulate (TSP) was calculated. Results indicate that filtering efficiency assumed by P2 certification in Australia was achieved for two of the three respirator models for DPM generated using the small diesel generator, whilst when the larger diesel engine was used, filtering efficiency requirements were met for all three filter models. These results suggest that the testing methodology specified for certification of personal respiratory protective devices by Standards Australia may not ensure adequate protection for respirator users against DPM under all circumstances of diesel generated particles

Are respiratory protection standards protecting worker health against ultrafine diesel particulate matter emissions? An Australian perspective

Poster presentation made at the 20th ETH-Conference on Combustion Generated Nanoparticles, 13-16 June 2016, Zurich, Switzerland. Aim: Ultrafine diesel engine emissions are known to cause adverse health impacts including lung cancer, cardiovascular and irritant effects (World Health Organisation 2012). Respiratory protective devices are commonly used to mitigate worker exposure to many hazardous contaminants, especially in heavy industry such as mining and refining. Current standards to evaluate penetration through respirator filter media may not consider ultrafine particles due to the diameter of the challenge aerosol and the detection limit of the instrument (Eninger et al. 2008). Nor do they test penetration at flow rates representative of moderate to heavy work rates. Research is currently being undertaken at the University of Wollongong, Australia, to develop a method to measure penetration through respirator filter media using diesel emissions, rather than the standard challenge aerosol of NaCl, at flow rates consistent with moderate to heavy work rates. Methods: Emissions from a Detroit D706 LTE diesel engine were fed into an experimental chamber which was purpose built for the study. Penetration through a range of commonly used respirator filters in Australian workplaces was determined by particle count at diameters ranging from 5.6 - 560nm, using an Engine Emissions Particle Sizer (EEPS). Penetration was also measured by mass of Elemental Carbon, using NIOSH 5040. Flow rates were as designated in AS/NZS 1716 (Standards Australia International Ltd & Standards New Zealand 2012) and ISO DIS 16975 - 1.2 Work Rates 2 and 3 (ISO 2015), consistent with moderate to heavy work rates. Results and Conclusions: A method has been developed and validated and a pilot study completed. Initial findings indicate penetration exceeded standards specified limits for filtering efficiency for a number of filters for the size range \u3c50 \u3enm, when measured as a function of particle count. Penetration through the filters was found to increase as flow rate increases. These results differed from the penetration by mass of elemental carbon through the respirator filters, using a paired samples t-test at a significance level of 0.05. This research is relevant as it has been postulated that ultrafine particles may contribute to adverse cardiovascular mortality and morbidity associated with diesel engine emissions (Martinelli, Olivieri & Girelli 2013) hence it is important to determine if these smaller size particles are penetrating through respirator filter media and may be inhaled by workers

Genome edited sheep and cattle

Genome editing tools enable efficient and accurate genome manipulation. An enhanced ability to modify the genomes of livestock species could be utilized to improve disease resistance, productivity or breeding capability as well as the generation of new biomedical models. To date, with respect to the direct injection of genome editor mRNA into livestock zygotes, this technology has been limited to the generation of pigs with edited genomes. To capture the far-reaching applications of gene-editing, from disease modelling to agricultural improvement, the technology must be easily applied to a number of species using a variety of approaches. In this study, we demonstrate zygote injection of TALEN mRNA can also produce gene-edited cattle and sheep. In both species we have targeted the myostatin (MSTN) gene. In addition, we report a critical innovation for application of gene-editing to the cattle industry whereby gene-edited calves can be produced with specified genetics by ovum pickup, in vitro fertilization and zygote microinjection (OPU-IVF-ZM). This provides a practical alternative to somatic cell nuclear transfer for gene knockout or introgression of desirable alleles into a target breed/genetic line

Development of an exposure control plan for diesel particulate matter: A case study in an underground metalliferous mine

Abstract presented at the 32nd Annual Conference & Exhibition of the Australian Institute of Occupational Hygienists Inc, 29 November - 3 December 2014, Melbourne, Australia

Looking back, moving forward: lessons learnt from accreditation of post graduate occupational hygiene courses

For many years AIOH has had a systematic method for reviewing and accrediting post graduate Occupational Hygiene Courses. Applying institutions would submit a range of course documentation which was then reviewed by a panel under the auspices of the Education Committee. During 2010, the Education Committee developed a set of Learning Outcomes (LO’s) for Universities applying for accreditation to map their course against prior to applying. Whilst the system in place has served AIOH well and produced good Graduate outcomes; the inclusion of LO’s will enable a more transparent and objective evaluation of courses. In a recent study trip; the system for Course Accreditation in the United States was reviewed and their findings will be compared against the system Australia (AIOH) has in place. This paper provides an important opportunity to look back and learn from organisations who have a more mature system than ours, to ensure the future of our profession by producing good Occupational Hygiene Practitioners and Full and active members of AIOH

Does Perception equal Protection? Occupational Noise Exposure & Hearing Protective Device Utilisation for Engineering Trades

The study examined exposure trends amongst a specific cohort of workers (n=55), loosely defined as engineering trade employees, but essentially comprising fitter and boilermaker trade disciplines at a variety of workplaces (n =6). Workers\u27 perceptions of their noise exposure was surveyed, and factors likely to influence positive or negative HPD use behaviours. The goal being to identify determinants of Hearing Protective Device (HPD) use behaviour and potentially apply targeted interventions to increase the efficacy of a workplace\u27s Hearing Conservation Program (HCP). Exposures for the study cohort were characterised utilising a combination of shift‐long personal noise dosimetry and short term area (at‐ear) measurements of specific tasks and activities. Risk perception and HPD use factors were examined utilising a questionnaire administered to study participants. Two distinct Similar Exposure Groups (SEGs) were confirmed, reflective of both fitting and boilermaker trade disciplines; both of which exhibited mean exposure confidence ranges wholly above the LAeq8hr 85dB(A) regulatory limit. Workers at the five workplaces where mandatory HPD use policies were implemented reported strong positive HPD use behaviours, and conversely at the sixth (and only) workplace where a mandatory HPD use policy was not implemented, negative HPD use behaviours were reported. On regression analysis this factor (mandatory HPD use policy) proved one of only 2 significant factors determining HPD use (p =\u3c0.01). The research concludes that a mandatory HPD use policy is an essential element in predicting positive HPD use behaviours to ensure exposure control

Evaluation of inorganic arsenic exposure at multi metal processing facility. When air monitoring alone just doesn\u27t work!

Metals smelting and processing has been associated with exposure to airborne inorganic arsenic and an increased risk of health effects. Biological monitoring on a metals processing site identified urinary arsenic concentrations exceeding corporate and ACGIH guidelines at levels associated with increased risks of health effects. Plant operators considered the inhalation of arsenic trioxide powder (As2O3), used in the process, as the source of their exposure. This study\u27s initial objective was to determine operator exposures to airborne inorganic arsenic. Two groups of plant operators participated in full shift personal air monitoring and biological monitoring over their working weeks. In parallel, wipe samples were taken from control rooms and grab sampling for arsine was carried out to capture a wider range of potential exposure routes. Air monitoring results did not approach exposure standards, with many below the limit of detection. In contrast, biological monitoring results exceeded corporate and the ACGIH guidelines indicating exposure via routes other than inhalation. This demonstrates that relying on air monitoring alone for exposure assessment is inadequate. The findings informed management and workers of practical measures required to adequately control process emissions, secondary exposure due to contaminated surfaces, and poor personal hygiene, prior to the closure of the plant and cessation of all associated processes in early 2015. Assessment of occupational exposure to substances with multiple exposure routes should not rely on air monitoring alone; but integrate other evaluative techniques such as biological monitoring (where available) to ensure exposure risk via all routes is adequately evaluated