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Chapter 5 – DFTD toxicology studies - the undone science

5.5 Toxicology studies into DFTD

In 2004 a National Dioxins Program accessed the concentrations of PCDD/PCDFs and PCBs in Australian fauna but it did not include Tasmanian devils amongst the marsupials studied.48 In the same year Robert Symons and colleagues from the Australian Government Analytical Laboratories (AGAL) published figures on levels of brominated flame retardants, in particular polybrominated diphenyl ethers (PBDEs) in Australian fauna.49 It reported detectable levels of PBDEs in all eight Tasmanian devils studied.50 The Tasmanian devil samples had been supplied by Dr Menna Jones.

46 Pearse AM & Swift K, 2006, Transmission of devil-facial-tumour disease, Nature, Vol.439(2), p 549

47 Vetter W, Recke R von der, Symons R & Pyecroft S, 2008, Determination of polybrominated biphenyls in Tasmanian devils (Sarcophilus harrisii) by gas chromatography coupled to electron capture negative ion tandem mass spectrometry or electron ionization high-resolution mass spectrometry, Rapid Communications in Mass Spectrometry, Vol 22, pp 4165-4170

48 Correll R, Muller J, Ellis D, Prange J, Gaus C, Shaw M, Holt E, Bauer U, Symons R & Burniston D, 2004, Dioxins in Fauna in Australia, National Dioxins Program Technical Report No. 7, Australian Government Department of the Environment and Heritage, Canberra

49 Symons R, Burniston N, Piro N, Stevenson G & Yates A, 2004, A study of the presence of brominated flame retardants in Australian fauna, Organohalogen Compounds Vol 66, pp 3959-3965.

50 Jones, M (unpublished) in T Ross, 2008, Persistent Chemicals in Tasmanian Devils, DPIW, Hobart, accessed 17 August 2009 http://tassiedevil.com.au/research.html

In 2005 the DPIPWE Progress Report identified as necessary the establishment of a pilot study of a statistically valid number of tissue samples to test for a range of toxins to determine the aetiology of the devil disease.51 The Progress Report also recommended that following the pilot study, normal devil cell cultures should be exposed to ten of the most commonly isolated toxins in amounts similar to those found in affected devils. Positive effects of the toxins on the cell cultures would indicate a need for a much larger project.

In April 2007 Simon Bevilacqua, a journalist with the Sunday Tasmanian, in an email dated 23 April, requested information about the toxicology studies for an article he wished to publish. Despite the 2004 results and the acknowledged need for toxicology studies, pilot studies had still not commenced. In the following month, prompted by Bevilacqua’s request, devil tissue was sent for toxicological analysis. The samples from 8 diseased devils and 8 non-diseased devils were sent from the DPIPWE Mt Pleasant laboratory to three separate laboratories. All the laboratories were accredited through the National Association of Technical Authorities (NATA), a private body, which is Australia’s government-endorsed national authority. At the time Stephen Pyecroft, Principal Veterinary Pathologist at the DPIPWE Mt Pleasant laboratory, was also on the NATA Veterinary Testing Accreditation Advisory Committee.52 The laboratories included the National Measurement Institute (NMI) in Sydney, the Alan Fletcher Research Station in Brisbane Queensland and Analytical Services Tasmania (AST) in Hobart.

51 Tasmanian Government Department of Primary Industries, Water and the Environment, 2005, Research into the Tasmanian Devil Facial Tumour Disease (DFTD) Progress Report, Department of Primary Industry, Water and Environment, Hobart, Tasmania

52 Bailey N, 2007, Veterinary Testing, NATA News, Issue 125, p 29. Available at:

http://www.nata.com.au/phocadownload/publications/Annualreport_newsletter/Newsletter/NN_Sept07re v2.pdf last accessed 6 January 2013

Whilst full results of these studies have never been published, Matthew Denholm of The Australian newspaper did obtained the results through a Freedom of Information request. A limited version is now available on a SourceWatch website.53 The NMI results were published by Vetter el al in the journal Rapid Communications in Mass Spectrometry in 2008, the only paper reporting the results of the studies.54 The results from the other laboratories were not published. There were however two official reviews of the results given by qualified scientists and published on the Save the Tasmanian Devil website, which are discussed below. The results from the various laboratories are summarized in Table 5.1 below.

Table 5.1 Results of toxicology studies Laboratory Chemicals tested Date of

Study

Conclusions National

Measurement Institute (NMI)

Dioxins – PCDD/PCDF, PAHs, PBDEs, organic pollutants, PBBs - fat samples

May 2007 Need for more studies into the reasonable levels of PBB residues (flame retardants) in devil

samples.55 Alan Fletcher

Research Station

Sodium Fluoroacetate (1080) poison

May 2007 1080 residue not detected in any devil samples

Analytical Services

Tasmania (AST)

Inorganic (arsenic, lead and mercury),Organo-chlorines

& metabolites,Organo-phosphates,Triazine herbicides (atrazine and simazine) – liver samples

May 2007 Inorganic analysis (arsenic, lead, mercury) - less than 1ppm detected,Organo-chlorines &

metabolites - one devil above detection range (limit <0.20 ppb),Organo-phosphates and triazine herbicides (atrazine and simazine) – not detected

53 Water Pollution in Tasmania published a limited version of the toxicology results. Available at:

http://www.sourcewatch.org/index.php?title=Water_pollution_in_Tasmania last accessed 29 August 2009.

54 Vetter W, Recke R von der, Symons R & Pyecroft S, 2008, Determination of polybrominated biphenyls in Tasmanian devils (Sarcophilus harrisii) by gas chromatography coupled to electron capture negative ion tandem mass spectrometry or electron ionization high-resolution mass spectrometry, Rapid Communications in Mass Spectrometry, Vol 22, pp 4165-4170

55 There was no significant difference between the levels of toxins found in diseased and non-diseased devils. Concerns raised over devil disease findings, ABC News, 22 January 2008. Available at:

http://www.abc.net.au/news/2008-01-22/concerns-raised-over-devil-disease-findings/1019328 last accessed 1 July 2013

5.5.1 The National Measurement Institute (NMI) and dioxin testing

The NMI is the institute responsible for Australia’s national infrastructure in analytical, biological, chemical and physical measurements. The NMI has the capability of carrying out what it terms on its website as ‘environmental analysis’ into dioxins, organic pollutants, pesticide contaminants as well as metal pollutants, microbiological contaminants and water analysis.56 Devil samples sent to the NMI were to be tested for a limited range of chemicals. The tests requested by DPIPWE to be carried out were for dioxins (PCDD/PCDF in I-TEQ, USEPA method 1668A – Isotype dilution), polycyclic aromatic hydrocarbons (PAHs) (indicator benzio-a-pyrene PBDEs), and polybrominated biphenyls (PBBs).57 Symons, who would be conducting the analyses at NMI, had arranged for co-authorship of the results, which were reported in the paper by Vetter et al in Rapid Communications in Mass Spectrometry in September 2008.58 Interestingly, the paper claimed that the Tasmanian devils were endangered due to a virus epidemic.

The results found concentrations of PBB153 in the range 0.3-11ng/g lipids in all but two devil samples. There was no significant difference between healthy and diseased devils. Levels were significantly lower than those causing toxic effect but ‘PBB concentrations were one level or even higher than PBDEs’ found in the National Dioxin Program 2004 study by Symons and colleagues.59 The paper also highlighted the need

56 Australian Government National Measurement Institute. nd, Environmental Testing. Available at:

http://www.measurement.gov.au/Services/EnvironmentalTesting/Pages/default.aspx last accessed 7 September 2011

57 Email from DPIPWE to NMI, dated 11 April 2007

58 Vetter W, Recke R von der, Symons R & Pyecroft S, 2008, Determination of polybrominated biphenyls in Tasmanian devils (Sarcophilus harrisii) by gas chromaography coupled to electron capture negative ion tandem mass spectrometry or electron ionization high-resolution mass spectrometry, Rapid

Communications in Mass Spectrometry, Vol 22, pp 4165-4170

59 ibid, 2008:4165

for more detailed environmental PBB residue studies in devils.60 PBBs have been shown to cause cancer in rats and the International Agency for Research on Cancer (IARC) has determined that PBBs are possibly carcinogenic to humans.61

The impact of these results is made clear in comments by Mariann Lloyd-Smith, co-chair of the International Persistent Organic Pollutants Elimination Network who stated

“[w]e were quite shocked” and she suggested that “[c]ertainly this study will have ramifications”.62 She further stated ‘[a]lthough the sample of the recent study was too small for firm conclusions …the toxins weakened the immune system and might theoretically be a factor in the disease that threatens to wipe out the Tasmanian devil.’63 Despite the concerns raised by Lloyd-Smith no further studies into the dioxins found in devil tissues were undertaken. The only peer-reviewed publication following the toxicology studies was a paper by Vetter at el, which only covered the results of the dioxin studies at the NMI. The authors claimed that ‘the contamination status of Tasmanian devils with anthropogenic pollutants was investigated’.64 However, support for this statement relied on a newspaper article, which does not make reference to pollutants, and the DPIPWE website where the link is broken. Other discrepancies in citation also occurred.

60 Vetter W, Recke R von der, Symons R & Pyecroft S, 2008, Determination of polybrominated biphenyls in Tasmanian devils (Sarcophilus harrisii) by gas chromaography coupled to electron capture negative ion tandem mass spectrometry or electron ionization high-resolution mass spectrometry, Rapid

Communications in Mass Spectrometry, Vol 22, pp 4165-4170

61 US Environmental Protection Agency, 2010, Emerging Contaminants – Polybrominated Diphenyl Ethers (PBDEs) and Polybrominated Biphenyls (PBBs), Available at:

http://www.epa.gov/fedfac/documents/emerging_contaminant_pbde_pbb.pdf last accessed 7 September 2011

62 Cosmos Magazine Online, 2008 Toxic chemicals: no link to devil facial tumours, Cosmos Media Pty Ltd. Available at http://www.cosmosmagazine.com/news/1817/toxic-chemicals-no-link-devil-facial-tumours last accessed 2 February 2010

63 ibid.

64 : Vetter W, Recke R von der, Symons R & Pyecroft S, 2008, Determination of polybrominated biphenyls in Tasmanian devils (Sarcophilus harrisii) by gas chromaography coupled to electron capture negative ion tandem mass spectrometry or electron ionization high-resolution mass spectrometry, Rapid Communications in Mass Spectrometry, Vol 22, pp 4165-4170, p 4166

McGlashan et al’s published paper documenting evidence of the need for an investigation into the possibility of a toxin-related aetiology from human land-use activities in Tasmania was not cited in the Vetter et al paper.65 Likewise, in 2007 in the journal EcoHealth Stephen Pyecroft, a co-author of the Vetter et al paper, in charge of the DPIPWE laboratory in Launceston, and on a NATA committee, also failed to cite the McGlashan et al publication.66 The reason for the omission of the McGlashan et al article is not known, but it is compatible with a chilling effect as described in Chapter 2.

5.5.2 Alan Fletcher Research Station – Sodium Fluoroacetate (1080) testing

Tasmanian devil liver samples were sent from the DPIPWE laboratory in Launceston to Robert Parker at the Alan Fletcher Research Station (AFRS) in Sherwood, Queensland for 1080 analysis. Parker had requested stomach content, liver and kidney as preferred samples.67 He specifically asked for the largest samples and specified that ‘with an old sample, you have degradation and contamination. These factors will reduce the effectiveness of the test’.68 Some of the samples sent to NMI had been stored since 2003 and it is probable that some of these same samples were sent to AFRS. In Australia there is no maximum residue limit (MRL) set for 1080 according to the APVMA.69 The results of the tissue samples indicated 1080 was not detected. This is not unexpected as

65 McGlashan, Neil D, DL Obendorf and JS Harington. 2006. “Aspects of the fatal malignant disease among the Tasmanian devil population (Sarcophilus laniarius).” European Journal of Oncology 11(2):95-102

66 Pyecroft SB, Pearse AM, Loh R, Swift K, Belov K, Fox N, Noonan E, Hayes D, Hyatt A, Wang L, Boyle D, Church J, Middleton D & Moore R, 2007, Towards a Case Definition for Devil Facial Tumour Disease: What Is It? EcoHealth Vol 4(3), pp 346-351

67 Email communication from Alan Fletcher Research Station to DPIWE Mt Pleasant Laboratory dated 23 May 2007

68 ibid.

69 Australian Government Australian Pesticides and Veterinary Medicines Authority, 2008, Sodium Fluoroacetate Final Review Report and Regulatory Decision. Available at:

http://www.apvma.gov.au/products/review/docs/1080_final_review_report.pdf last accessed 6 September 2011

the tendency for 1080 is not to accumulate in tissue post exposure.70 There is no published report on the analysis undertaken at this laboratory.

5.5.3 Analytical Services Tasmania (AST) – testing of agrichemicals used in Tasmania

The critical analysis on the devil tissues for agrichemicals used in plantation forests was undertaken by the Tasmanian government DPIPWE operated AST laboratory. At the time the DPIPWE was also in charge of:

• monitoring chemicals used in forestry;

• analyses carried out by AST;

• funding the devil research through UTAS; and

• analyses of chemical residue in the devil tissues.

A conflict of interest would seem to be apparent when the body charged with enabling the progress of the forestry industry, DPIPWE, is also charged with monitoring chemicals in the environment and assessing chemical residue in devil tissues used by that industry.

It is likely that samples similar to those sent to the other laboratories were also sent to AST. The AST is an accredited NATA laboratory for the testing of chemicals but only in water and sediment, not in biological samples such as devil tissue.71 The analyses at AST were for endocrine disrupters, such as atrazine, which are usually detected in urine.72 It is also known that there are critical times in the development of an organism when these chemicals cause the most damage with effects not manifest until later in life

70 Twigg LE, Lowe TJ, Kirkpatrick WE & Martin GR, 2003, Tissue residue levels in rabbits and rats poisoned with 1080 One-shot bait and the location of poisoned rabbit carcasses, Wildlife Research Vol 30, pp 621-631

71 Personal communication with National Association of Testing Authorities (NATA), Brisbane, Queensland dated 19 May 2009

72 Zhou Z, Jin M, Ding J, Zhou Y, Zheng J & Chen H., 2007, Rapid detection of atrazine and its metabolite in raw urine by exractive electrospray ionization mass spectrometry, Biomedical and Life Sciences 3(2), pp 101-104

and in some instances in the next generation.73 Therefore, non-detection of endocrine disrupting chemicals is not necessarily an indicator of lack of harm. The results of the tests from AST were that agrichemicals, including the triazines (atrazine/simazine), were undetected. A consequence of the chemicals being undetected is that further scientific experiments on the effects of these chemicals on devils, has been left undone.

It would also appear that through a lack of appropriate studies the AST avoided producing ‘negative knowledge’, namely scientific results which may have proved harmful to vested interests or those funding the research. Atrazine and its metabolites enter some organs or fat but do not build up or remain in the body, usually leaving through the urine within 24-48 hours.74 They are absorbed from the gastro-intestinal tract with the highest concentrations usually detected in red blood cells.75 No testing was done of these chemicals in either blood or urine of the devils.

Further studies into the role of these chemicals and endocrinology studies, identified in the DPIPWE report in 2005, should not be avoided or abandoned simply because these limited tests resulted in non-detection. When tests for chemicals that are known endocrine disrupters, such as the triazines, atrazine and simazine, come up negative scientists then must decide whether further studies are warranted. This raises further questions - are there limits to detection, that is, is the science undoable?