Asbestos – Definitely Not Dietary Fibre

If ingesting asbestos is potentially carcinogenic – and all of our old water pipes are made of asbestos cement resulting in high levels of asbestos in our drinking water – it is time to determine just what level of asbestos in drinking water is ‘safe’.

Everybody knows breathing asbestos is bad for you… linked to malignant mesothelioma and other lung cancers, asbestos has been completely banned for use or import in Australia since 2003, with significant discontinuation of use in building products starting in the early 80s.¹ Widely used asbestos products included roof tiles, linoleum, fencing materials, window putty, rubber gaskets, paints, thermal insulation and more. Even after the widespread ban on all asbestos products was put in place, asbestos containing products are still present in existing buildings, asbestos cement water pipes, and imported products that should be asbestos free (eg. crayons, gaskets, paints etc).^1,2

An interesting fact about mesothelioma that appears well known in the medical community but is glossed over in industrial and commercial settings is that mesothelioma can develop in the lungs (pleural mesothelioma) and in the gastrointestinal system (peritoneal mesothelioma) and both forms are primarily caused by asbestos exposure.³  Perhaps this connection has been largely overlooked due to the lesser risk of gastrointestinal cancers than lung cancers, with peritoneal mesothelioma accounting for less than 20% of asbestos related cancers and developing 20 to 50 years after exposure.⁴ Given the high incidence of asbestos related cancers, this 20% should be significant enough to take notice, even without the links to other gastrointestinal cancers.

The majority of the publicity surrounding asbestos focusses on the effect on the lungs, with recommendations about masks to prevent inhalation, stringent conditions for transport, and air monitoring to determine risk. To the casual observer it would appear that inhalation is the only hazard associated with asbestos, and current global and local guidelines reinforce this notion.

The Dept of Health, WA states⁵ that “While studies have clearly shown that asbestos poses a serious health risk when it is dry and inhaled, there is very little evidence to show that asbestos fibres will cause any harm when they are wet and swallowed. The effects of asbestos in the water supply have been studied extensively, and results have not shown an elevated risk of asbestos-related disease. In addition, although inhaled asbestos is a known carcinogen (cancer-causing substance), asbestos when swallowed is considered to pose very little, if any, carcinogenic risk to human health.” Additionally, the Dept of Health, WA mentions  that the 2004 Australian Drinking Water Guidelines (2004 ADWG) and World Health Organisation have not set a guideline value for asbestos due to the absence of evidence that asbestos is hazardous to health.

The World Health Organisation (WHO) states⁶ in their 1996 documentation that “Although asbestos is a known human carcinogen by the inhalation route, available epidemiological studies do not support the hypothesis that an increased cancer risk is associated with the ingestion of asbestos in drinking-water.” They reinforce this in 2013, stating “There is therefore no consistent, convincing evidence that ingested asbestos is hazardous to health, and it is concluded that there is no need to establish a guideline for asbestos in drinking-water.”

The idea that ingestion of asbestos and asbestiform minerals could cause gastrointestinal cancer is not new – there are significant number of studies conducted through the late 1970s and early 1980s which investigate the possibility. Many of these studies conclude that due to small cohort sizes and the long delay between exposure and developing the disease, further study is required.⁷ Even with these limitations, some studies found a probable link between asbestos ingestion and gastrointestinal cancers, particularly stomach cancer, in both occupational⁸ and non-occupational¹⁰ settings. It was also raised that the comorbidity of smoking and asbestos inhalation obscured the significance of the link between asbestos ingestion and gastrointestinal cancers.

So, if ingesting asbestos is potentially carcinogenic, and all of our old water pipes and tanks are made of asbestos cement resulting in high levels of asbestos in our drinking water, is it time to determine just what level of asbestos in drinking water is ‘safe’?

Again, this isn’t a new concept. It was determined in 1971⁹ that some beers contained low levels of asbestos. The asbestos was linked back to fibres released from the asbestos cement pipes used to transport the water, and it was shown that the fine fibres were able to pass through the filtration systems of both the water system and the brewery. Following on from this was the Duluth study¹⁰ between 1976 and 1981. After higher than expected levels of asbestos fibres were found in the drinking water of Duluth, Minnesota, USA, a study was started to monitor the incidence of cancers in the region compared with nearby regions over the same time period. The study noted an increase in cancer rates and a greater increase in cancer mortality between Duluth and the two comparative regions. In 1997, an epidemiological study of drinking water and cancer¹¹ again suggested elevated levels of cancer in exposed populations and also noted that “As topics for epidemiologic evaluation, drinking water contaminants pose methodologic problems common to studies designed to detect relatively small elevations in risk, with the added challenge of assessing exposures for many years in the past.”

More recent studies have been more conclusive, although still there is significant need for further research. In 2005, a study of 726 lighthouse keepers in Norway was published¹², showing the effect of asbestos in their drinking water on cancer of the gastrointestinal tract. The study was performed between 1960 and 2002 on lighthouse keepers first employed between 1917 and 1967. One of the first studies to more fully allow for the long delay in onset of asbestos related cancers, the study showed significantly elevated risk of stomach cancer among those exposed to asbestos in drinking water, and possible links to colon cancer.

In 2013 a literature review¹³ examined the published evidence so far linking asbestos to gastrointestinal cancer and summarised it in a useful table.^13a Reviewing over 50 papers, the article shows the number of positive and negative links indicated in published works associated with types of gastrointestinal cancers and with the different types of asbestos. This article also notes dosages between < 1 million fibres per liter (MFL), cited as probably not harmful, to > 1 billion MFL, probably harmful, although doesn’t take into account water consumption.

This year, another review has been published¹⁴, calling for further studies and the possible establishment of monitoring plans. The expert commentary provided states “A risk threshold ([asbestos fibre] concentration in drinking water) for digestive cancers has not been convincingly identified so far and regulations, where adopted, have weak scientific basis and may not be adequate. With further and more definitive studies, evidence might become sufficient to justify monitoring plans, persuade countries with no current limits to set a maximum level of AFs in drinking water and might induce a revision of the existing legislations, pointing to efficient primary prevention policies.” The article links asbestos ingestion to gastric and colorectal cancer, toxic effects on the stomach, ileum and colon, histological alterations, and the ability to cross the placenta and enter foetal organs (including the liver) as well as act as a co-carcinogen agent.

Dosage effects have been inadequately studied, which makes developing guidelines very difficult. It is important that, instead of equating lack of evidence to lack of risk, we acknowledge the possibility of risk associated with ingesting asbestos and begin the journey of understanding and regulating asbestos in drinking water before many more people are subjected to the effects.

1. Department of Health, 2013, When and where was asbestos used?. Available at: http://www.health.gov.au/internet/publications/publishing.nsf/Content/asbestos-toc~asbestos-when-and-where
2. Border Force, Asbestos. Available at: http://www.border.gov.au/Busi/cargo-support-trade-and-goods/importing-goods/prohibited-and-restricted/asbestos
3. Bofetta, P. (2006) Epidemiology of peritoneal mesothelioma: a review, Annals of Oncology 18: 985–990, Available at: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.521.9698&rep=rep1&type=pdf
4. Conway, W. C. (2017), Peritoneal Mesothelioma, The Mesothelioma Center. Available at: https://www.asbestos.com/mesothelioma/peritoneal.php
5. Department of Health (2016), Asbestos in drinking water. Available at: http://ww2.health.wa.gov.au/Articles/A_E/Asbestos-in-drinking-water
6. WHO (1996), Asbestos in Drinking-water: Background document for development of
   WHO Guidelines for Drinking-water Quality, World Health Organisation. Available at: http://www.who.int/water_sanitation_health/water-quality/guidelines/chemicals/asbestos.pdf?ua=1
7. Morgan, R. W., Foliart, D. E., Wong, O. (1985), Asbestos and Gastrointestinal Cancer, West J Med. 143(1): 60–65. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1306225/
8. Selikoff, I. J. (1974), Epidemiology of gastrointestinal cancer, Environ Health Perspect. 9: 299–305. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1475395/
9. Cunningham, H. M., Pontefract, R. (1971), Asbestos Fibres in Beverages and Drinking Water, Nature 232, 332 – 333. Available at: http://www.nature.com/nature/journal/v232/n5309/abs/232332a0.html
10. Sigurdson, E. E. et al (1981), Cancer morbidity investigations: Lessons from the Duluth study of possible effects of asbestos in drinking water, Environmental Research 25(1):50-61. Available at: (http://www.sciencedirect.com/science/article/pii/0013935181900797
11. Kantor, K. P. (1997), Drinking water and cancer, Cancer Causes & Control 8(3):292–308. Available at: https://link.springer.com/article/10.1023/A:1018444902486
12. Kjaerheim, K. et al (2005), Cancer of the gastrointestinal tract and exposure to asbestos in drinking water among lighthouse keepers (Norway), Cancer Causes & Control 16(5):593-8. Available at: https://www.ncbi.nlm.nih.gov/pubmed/15986115
13. Kim, S. J. et al (2013), Asbestos-Induced Gastrointestinal Cancer: An Update, J Gastrointest Dig Syst. 3(3): 135. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4856305/
    1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4856305/table/T1/
14. Di Ciaula, A. (2017), Asbestos ingestion and gastrointestinal cancer: a possible underestimated hazard, Expert Review of Gastroenterology & Hepatology 11(5):419-425. Available here: http://www.tandfonline.com/doi/abs/10.1080/17474124.2017.1300528

The majority of things around you (and inside you!) are made of atoms. Atoms are arranged in some sort of order – they can be found in meandering long chain molecules in fats and proteins and the like, in cute little pairs or triplets floating around as gases, or arranged in military order in iron and diamond.

Those materials where the atoms are arranged in repeating patterns, like wallpaper or synchronised swimmers, are referred to as ‘crystalline’ materials. Any material that is not crystalline (or semi-crystalline but that’s a whole other kettle of eels) is considered amorphous.

Crystalline vs Amorphous

When X-rays interact with these crystalline materials, they diffract the radiation a different amount depending on the distance between the atom and its neighbours. When many X-rays interact, these many diffractions build up a pattern that allows us to see how the atoms are arranged in the solid. Since different sized atoms result in different sized gaps between the atoms in the structure, which changes this diffraction pattern.

The arrangement, or ‘packing’ of the atoms results in the main pattern of the resulting diffraction. If you think about how you could stack ping pong balls in a plasic tube, or stack apples on a table, that gives you an idea of different crystal structures that might be possible. The basic crystal structures are shown below.

The way these atoms are arranged, the crystal structure, determines how a crystal is formed and grows over time – you may have noticed the little hematite cubes you can see at the markets, or the way some gemstones form a hexagonal shape. This arrangement of atoms determined how the crystal will look on a macro scale. Sometimes individual atoms in a crystal structure will be substituted with another atom type (for example manganese for iron), which usually won’t change the overall structure, but might change the colour of the crystal or the way the light bounces through it.

X-ray diffraction analysis uses this unique interaction between X-ray radiation and crystalline materials to build a diffraction pattern which is then compared to a huge database of reference patterns in order to determine which crystal structures are present in the material. This allows up to tell the difference between Halite and Sylvite, and between Goethite and Hematite without any trouble.

Want to identify your crystals? Ask for X-ray Diffraction!

Nimue Pendragon

February got off to a flying start with Ian and I heading to Melbourne for the Australian X-ray Analytical Association Workshops, Conference and Exhibitions. Nathan Webster of CSIRO and his team at AXAA did a fantastic job of compiling an interesting mix of speakers covering innovations and developments in x-ray diffraction and x-ray fluorescence techniques and instrumentation.

 Ian Madsen of CSIRO (ret.) and Matthew Rowles of Curtin University kicked off the XRD proceedings with workshops spanning everything from the basics of x-ray diffraction principles to advanced quantitative analysis techniques. There were also informative presentations from Mark Raven of CSIRO on the challenges of quantitative XRD analysis on clay samples as well as a few cool projects working with carbon sequestration by Jessica Hamilton of Monash University and selective gas adsorption with metal organic materials by Josie Auckett of ANSTO to name but a few.

 Dr. Helen Maynard-Casely’s (of ANSTO) public lecture gave an interesting insight into how planetary scientists can recreate the high pressure conditions deep within the core of planets and Michael Varcoe-Cocks of the National Gallery of Victoria presented the very dramatic transformations that artwork can undergo when XRF techniques are used to aid in the restoration process. You can watch them both here.

 We enjoyed an entertaining dinner with great food and wine where Greg Moore and Mark Raven were honoured with the Keith Norrish AXAA Award for Excellence in X-ray Fluorescence Analysis and Bob Cheary AXAA Award for Excellence in X-ray Diffraction Analysis respectively. To finish off the week we were treated to a tour of the Australian Synchrotron. The whole conference was a great experience where we were exposed to new tips, tricks and techniques for quantitative XRD analysis many of which we are looking to incorporate into the analyses we offer to further improve the quality of the results we provide. Here’s hoping we get invited back to the next AXAA conference!

DIN’t you hear? Corrosivity testing for bulk shipping is having an overhaul.

As many of you are aware, shipping requirements regulations are constantly being updated to ensure maritime and dockside safety. One of the recent focal points has been the determination of Class 8 and MHB corrosivity in bulk cargoes.

Late last year AMSA released Exemption 5450 which allows certain cargoes to be tested using an alternate test method for corrosivity determination. These cargoes have been shown to be consistently problematic when it comes to the determination of the likelihood of localised corrosion.

This exemption only applies to Coal, Bauxite, Iron Ore and Iron Ore Fines. For concentrates, you’ll be looking at Exemption 5451 for now.

So what is this alternate test?

Instead of trying to experimentally simulate the environment in a ship’s hull and measuring the corrosion rate, DIN 50292-3 allows a series of chemical and physical tests of the product to be used to predict the likelihood of the product causing serious localised corrosion.

The result of this change is that producers can obtain a more consistent result with a suite of standard laboratory tests, and be confident that their product is as safe as they think!

A significant amount of research and parallel testing has been performed by Microanalysis Australia and Curtin University on behalf of a number of industry bodies to verify the efficacy and practicality of the new test.

Please note that this exemption supersedes EX5389.

Ask us about MHB and IMDG classification for your cargo!

Cargo Liquefaction is a concern for shippers and mariners alike, and when managed poorly can result in tragic loss of life and massive costs. Following several incidents over the past few years, the standard test method for transportable moisture limit (TML) and the laboratories that perform the tests have come under scrutiny under a drive to ensure the safety of crew and cargoes while maintaining commercial viability.

Microanalysis Australia has been working with shipping and mining companies to determine the suitability of relevant test methods for different products, providing rapid and relevant feedback about products, results and test suitability, and offering up-to-date information and certificates. This includes involvement in the validation and implementation of the new Modified Proctor-Fagerberg TML test for Iron Ore Fines, and providing test results for a wide range of shippers around the world.

 Interest has increased in the possibility of liquefaction of products that were previously considered unlikely to liquefy, including bauxite and alumina. The suitability of the available test methods for individual products with wildly varying physical and chemical properties is also acutely relevant.

 TML determination is a delicate science, which results in a report without which a ship containing bulk cargo is unable to leave port. The TML value represents a ‘safe’ moisture content, below which the cargo is unlikely to undergo liquefaction and endanger the ship and crew. It is the responsibility of the shipper to provide a moisture management plan and to prove that the cargo is being shipped with a moisture content below the TML.

 There are currently three techniques suggested in the International Maritime Organisation’s IMSBC code – the flow table test, using impact testing to simulate plastic flow; the Proctor-Fagerberg test, based on a standard soil compaction test to determine saturation point; and the Penetration test, using vibrational testing to simulate liquefaction conditions. Each technique is uniquely suited to certain sample types, so explicit knowledge of the sample and the test specifics are paramount to an easy journey out of the port. Not everyone needs to be an expert – just employ a laboratory that is!

 Another rising concern is the effect on the environment when something does go wrong. The regulations around bulk cargo classification are getting tighter. It is important for a cleanup crew to know if a product is hazardous to a marine environment (HME) and there is increasing demand for classification testing using marine transformation dissolution testing as more products are required to comply with Marpol Annex V. Microanalysis Australia is able to perform the relevant dissolution testing for marine and freshwater environments, as well as biological toxicity studies in synthetic stomach or lung fluids.

 These changes are occurring as the Australian Maritime Safety Authority (AMSA) are continually reviewing and improving the guidelines to improve the safety of crew and cargoes. It is important to keep track of major changes and make sure that shippers know ahead of time what will be required of them and that ports are aware of the changes affecting them. Microanalysis Australia has a long history of providing the latest information to shippers and ports and assisting with understanding regulations and guidelines to help shipments go out smoothly and without incident.

The above article appeared in the November/December 2016 Australian Ports News – Page 5