Research Programme. Operations. Review of drug testing methodologies

Transcription

1 Research Programme Operations Review of drug testing methodologies

2 HSL, Broad Lane, Sheffield, S3 7HQ Review of Drug Testing Methodologies (T133), Prepared for RSSB Parts 1-3 HE 04/04 Project Leader: Howard Mason Author(s): Peter Akrill and Howard Mason Science Group: Health Sciences Group

3 DISTRIBUTION Toyin Davies Mick Stormonth Stakeholders Norman West RSSB Research Manager RSSB Technical Project Officer As nominated by RSSB HSL Operations Director HSL report approval: Dr Andrew Curran Date of issue: Job number: JC Registry file: HE/PR/54/2004 Electronic filename: RSSB phase 1, 2 and 3 report.doc Copyright 2004 Rail Safety and Standards Board This publication may be reproduced free of charge for research, private study or for internal circulation within an organisation. This is subject to it being reproduced and referenced accurately and not being used in a misleading context. The material must be acknowledged as the copyright of Rail Safety and Standards Board and the title of the publication specified accordingly. For any other use of the material please apply to RSSB's Head of Research and Development for permission. Any additional queries can be directed to research@rssb.co.uk. This publication can be accessed via the RSSB website This report and the work it describes were undertaken by the Health and Safety Laboratory under contract to RSSB. Its contents, including any opinions and/or conclusions expressed or recommendations made, do not necessarily reflect policy or view of the Health and Safety Executive.

4 EXECUTIVE SUMMARY Introduction This report reviews the currently available drug testing methods in terms of their suitability for use by the UK railway industry. It also covers the medico-toxicological, ethical, legal defensibility and other issues related to the implementation of the various testing methods that relate to the Railway Group Standard GE/RT/8070. The report consists of three sections; the first deals with technical issues concerning the various testing methods that are available for a workplace programme of drug testing, the second section discusses issues concerned with the implementation of testing strategies developed from section one, including the medical and legal defensibility of testing and any arising ethical issues. Section 3 deals with the appropriate use of drug testing within a rehabilitation programme or allowing re-employment as a relevant person defined in GE/RT/8070. Consideration of this executive summary together with sections 1 and 2 of this report should help those with the appropriate responsibility within different elements of the railway industry to consider the most appropriate workplace-testing programme (if necessary) that meets the Railway Group Standard GE/RT/8070, Transport and Works Act (1992) and any other relevant safety legislation. We would stress that whereas the Group Standard discusses drugs and alcohol in terms of accident/incident prevention and impairment of performance, drug testing is, except for alcohol, very largely about the detection of illicit drugs. The potential for both prescribed and over the counter medication to have an effect on performance, reflected in 3.13 of the Group Standard, is not considered here, but should not be forgotten, likewise the potential abuse of some such medications. A key driver for this report was the outcome of an ATOC meeting of the 14 th May 2002 where the applicability of Altrix s oral fluid drug analysis based on the Intercept oral fluid collection system and trialled at Midland Mainline was discussed. A number of specific and general questions arose directly from this seminar, and from subsequent discussion and correspondence within industry stakeholders. These questions concerned the applicability of current and possible alternative workplace drug testing systems, largely based on sampling matrices such as oral fluid. Responses to these specific issues are detailed in the conclusions of this executive summary, and underpinned by the evidence in the body of the report. Other issues which have been raised during discussions or communication with stakeholders within the railway industry, and by others involved in applying workplace drug testing are also addressed. Methodology The evidence produced in this report has largely relied on peer-reviewed data published in scientific journals. Much of this data has not necessarily been produced in accredited laboratories undertaking routine drug testing, but in applied research laboratories, where such testing techniques are developed. The peer-review process is meant to test the nature of the data and its interpretation by other experts prior to its iii

5 publication. Many of these studies have been carried out on volunteers and/or those with drug habits under carefully controlled conditions of drug administration. These studies are fundamental in proving the sensitivity and accuracy of the laboratory analytical techniques for detecting drugs in differing sampling media (urine, oral fluid, hair), for defining windows of detection for individual drugs, and investigating the ability to discriminate between individuals who have taken the drug or not. A smaller body of published peer-reviewed evidence relates to the outcomes from the practical use of work place drug testing. There are also a large number of published articles on workplace drug testing which are not necessarily within the peer-review process. Some of these articles seem to show a bias that makes them unhelpful. Other information for this review has come from commercial laboratories undertaking routine drug testing. Such data may be open to the criticism of potential bias. However, we would highlight the openness and help that has been given by those laboratories with whom we have had contact. Lastly, there are the opinions and experience of those who are involved in workplace drug testing from various perspectives. While relying largely on peer-reviewed data in this report, it has been necessary and useful to include the non-peer review data and opinions of those with experience. In reaching any conclusion we have attempted to investigate the consistency of evidence from these different sources, highlight any inconsistencies and areas where evidence may be lacking. However, we would stress that the conclusions are based on the available scientific evidence. Conclusions Part 1 Technical Issues General Comments Information on the pattern of drug misuse in the general and working UK population is poor. However, the availability of validated drug testing methods largely maps to the pattern of drug misuse, except for possibly the abuse of amyl nitrite and the hallucinogens contained in magic mushrooms. For these drugs we could find little evidence of validated methods for their detection. We would stress that the largest abuse problem relates to the legal drug alcohol. Cannabis is by far the most commonly used illicit drug. Its use in the general population appears to be five-fold higher than any other illicit substance. Workplace drug testing currently remains predominantly performed using urine samples. Therefore there is a wealth of expertise in the analysis and interpretation of urine drug test results. This reflects that urine testing is the defacto standard method, not that it is the gold standard for drug testing. Other sampling media, such as oral fluid/saliva, sweat and hair have been investigated as potential alternative sampling media. Some of these alternative sampling media, especially oral fluid and hair, have shown significant increases in their use within routine workplace testing schemes in recent years. iv

6 Urine, oral fluid and sweat drug tests reflect recent exposure, whereas hair testing is about past drug misuse over periods of time of weeks and many months. This will obviously influence the applicability of such samples for preemployment, due-cause and rehabilitation purposes. Therefore hair measurements would not be applicable for due-cause testing but are considered more applicable to pre-employment and rehabilitation testing. There is extensive scientific information on urine testing, but the scientific data validating the use of oral fluid and hair, as alternative sampling techniques appears satisfactory to justify their potential routine use, rather than as research tools under development. This includes data on screening and confirmatory analyses, and interpretation of results. This view is substantiated by the recent proposed guidelines from an authoritative body (SAMHSA, USA), which oversees the influential federal workplace drug testing. Published data and limited information from a UK user of sweat testing highlight possible concerns about the specificity of sweat wipe testing for some drugs. Patches worn to collect sweat over extended period have been suggested, but in our opinion are not suitable within a UK workplace scheme. There is only limited published data from large-scale workplace studies that compares the efficacy of a workplace drug-testing programme based on oral fluid versus urine testing. However, this data (which includes the cannabis, cocaine, amphetamine, and opiate based drugs) and discussion with those undertaking such analyses suggests that they have comparable efficiency in detecting recent drug use, if appropriately applied. Oral fluid testing is practically much easier to carry out than urine testing in ensuring that attempts to suborn testing are not being used. It may also reduce the indignity that some workers feel during supervised urine collections. Oral fluid testing needs no specially prepared facilities for sample collection; the level of expertise and training for those collecting oral fluid is less than that needed for urine collection. Such factors may be particularly advantageous in the railway industry where many staff are likely to be random or due-cause tested may be geographically dispersed. It may have implications for the current need to alter staff rosters for individuals to attend appropriate facilities for urine testing. Oral fluid and urine drug testing detect recent drug use. The time window of detection for most drugs in oral fluid is somewhat shorter than that for urine, however it depends on the dose of drug, the extent of chronic drug use and the cut-off that is applied to define a positive result. A shorter detection window coupled with a more immediate detection after drug use in oral fluid measurements may indicate a closer relation with impairment, and therefore of particular relevance in due-cause testing. The shorter window of detection for oral fluid measurements suggests that the period of pre-announcement that an individual receives prior to testing should be as short as possible in order that charges of behaviour modification to produce a negative result cannot be levelled. We conclude that pre-warning of testing should only be of the order of a few hours for testing by oral fluid and probably considerably less than 24 hours for urine testing to ensure that any random testing scheme fulfils its purpose. v

7 Oral fluid collection employing a collection device appears more acceptable than direct spitting. Few oral fluid collection devices have been validated comprehensively for drugs testing. The Intercept and Omnisal devices have been validated for various drugs and employed routinely by different laboratories. Given the influence that a collection device may have on analytical results, the particular collection device will be allied to the laboratory undertaking the analyses. There may be differences between the collection devices in nature of the oral fluid absorbed onto specific devices. However, how drugs and their metabolites get into oral fluids suggest that such differences are not of practical importance. Of key importance is the use of a collection device that has been appropriately validated for all drugs of interest. Expertise to carry out drug testing and interpret the results in oral fluid and hair is currently found in considerably fewer testing organisations than for urine testing. However, centres of appropriate expertise do exist. If testing in these alternative samples to urine increases, the establishment of routine, independent quality assurance schemes, as exists for urine testing, will be necessary to show the competency of the laboratory and the quality of the results obtained. We acknowledge that moves in this direction are on going. Similar considerations apply to the accreditation of laboratories undertaking workplace drug testing analyses in these alternate matrices. Part 2 Legal, Ethical and Implementation Issues General Comments There is little scientific evidence on the acceptability to workforces between the various sampling media (urine, oral fluid and hair). A wide range of opinions on the use of urine samples have been expressed; from degrading to perfectly acceptable when undertaken by trained staff in appropriate facilities. Direct spitting for oral fluid collections may not be acceptable for some individuals on social, cultural grounds. Chain of custody (CoC) for donated samples is one of the key elements in the legal defensibility of individual results and maintaining the credibility of schemes in general. CoC maintains a proved link between a donated sample and the results reported for that sample and ensuring that samples are stored appropriately. CoC procedures for workplace testing are modelled on the handling of forensic samples; the same principles are applicable for any sampling media. Confirmatory analytical methods based on mass-spectrometry are essential to guard against false positive results. Other safeguards include the use of conservatively defined cut-offs concentration for any drugs in the sample; only drug concentrations above the cut-off being taken as a positive result. Definition of the cut-off takes into account the detection limit and imprecision of the method, the possible legitimate use of the drug or precursor drugs and the possibility of exposure not related to drug abuse. Expert review of any positive analytical result is also crucial, rather than necessarily relying on the outcome of the laboratory confirmatory test, as some positive results may still be possible vi

8 due to non-abuse reasons. Best practice guidelines indicate the important role of the Medical Review Officer (MRO). The MRO is a physician who can issue a negative report for a positive analytical result based on consultation with the donor in question, the donor s GP, the laboratory toxicologist and information supplied by the donor at the time of sampling (e.g. prior medication). While the necessary experience, competency and accreditation pathway to undertake an MRO role are well defined in the USA, they are less well defined in the UK and EU. Concerns about ethical and legal issues about workplace drug testing have led to a recent UK independent review ( Rowntree/IIDTW ). Interestingly, there is not substantial UK evidence that drug testing causes significant problems in the area of employment law. While identifying some current uncertainties in legal aspects (employment, health and safety, data protection, human rights and discrimination legislation) and concerns about workplace drug testing in general, the report indicates that drug testing related to safety critical activities is currently defensible. The IIDTW review noted that drug policies including testing are more successful when conceived as a component of health and welfare policy rather than primarily a disciplinary matter. It also highlighted that there is a need for proper consultation with staff representatives/unions and that drug testing is no substitute for good management practice. However legal opinions supplied to the IIDTW highlighted that recent legislation (e.g. Human Rights Act 1998 and Data Protection Act 1998) is likely to shift the perceived previous imbalance between the interests of employer and employee in workplace drug testing. Interpretation of these Acts and guidelines from the Information Commissioner may constrain the general use of workplace drug testing and how an employer may handle and store data on an individual s drug tests. These legal opinions noted uncertainties in some of the legal issues but that certain trends were apparent. These include moves towards detection of impairment at work, rather than identifying illegal drug use over a much longer time scale, and that appropriate distinction between safety sensitive and nonsafety sensitive roles must have been made. Unfortunately at this current time the Information Commissioner s Part Four Guidance on Information about Workers Health, which specifically addresses drug testing issues remains in draft form. This draft document highlights that safety issues can arise from legal as well as illegal drugs, and states that other than in the most safety critical areas, regular drug testing is unlikely to be justified unless there is reasonable suspicion of drug use that has an impact on safety. It also notes that any drug testing must provide better evidence of impairment than less intrusive alternatives such as cognitive ability testing. Employers intending to carry out drug testing should use the least intrusive method possible compatible with the benefits they intend, but detecting recent drug use rather than use over a much wider time-scale. However, the draft guidance highlights that health and safety law may be an identifiable reason for appropriate drug testing of those in safety sensitive jobs. vii

9 Part 3 Rehabilitation and monitoring/testing arrangements Rehabilitation of employees with alcohol/drug problems either detected by testing or preferably through voluntary admission has occurred in safety critical industries. A return to safety critical activities involves appropriate treatment and with continuing monitoring and assessment. The choice of treatment/rehabilitation for any individual with some form of drug or alcohol problem needs expert assessment, and is best arranged through occupational health department or provider. Problems that arise largely relate to alcohol rather than illicit drugs. There is considerable evidence on effective treatment programmes for social alcohol abuse, a significant amount arising from drink-driving issues. Department for Transport approved courses for behaviour modification through education in drivers found guilty of drink-driving offences are widely available, but no such courses are available for those guilty of drug-driving offences. There is increasing availability of different drug treatment/rehabilitation programmes for the wide range of dependency problems in individuals. The National Treatment Agency within the NHS is spearheading the increase in available and effective treatment schemes. However, it is likely that the expansion is largely in services to address drug dependency in those showing serious social dysfunction or criminal activity. The US transport regulatory model for rehabilitation/treatment in those with a drugs or alcohol violation involve the defined and accredited role of Substance Abuse Professional. This expert role, independent of employer or employee, is to define and ensure completion of an appropriate treatment regime for the individual before they can be returned to a safety critical work. The period of removal from safety critical activities for those with drugs or alcohol violation according to the US regulations is not stipulated. The Substance Abuse Professional also defines the necessary level of monitoring and assessment of the individual returning to such duties. Urine and oral fluid testing may have a role within rehabilitation, pre- and postreturn to duty, but with consideration that they reflect only recent exposure and the need for being unannounced to maintain the value of such testing. This may suggest an increased frequency of unannounced testing for that individual during an initial monitoring period of re-commencing safety critical activities. Hair analysis may be a useful technique for both employer and employee to prove drug abstinence over a longer time frame of weeks or months for return-to-duty testing and post-return-to-duty testing. Summary of possible ways forward On balance, we feel that the scientific evidence for workplace drug testing based on laboratory analysis of urine or oral fluid samples are largely equivalent. Neither is perfect and analytical improvements continue for both sample types in detecting recent drug use. The use of appropriate chain of custody procedures, the availability of expert toxicological and MRO functions, as well as laboratory analytical techniques are crucial viii

10 to ensure the validity of final results, which can have serious employment consequences. While suggested chain of custody procedures appear robust and applicable to any type of sample (e.g. urine, oral fluid, hair), we feel that the role of the MRO and the competency and training necessary to undertake this crucial role is less well developed. While largely scientifically comparable, oral fluid testing may have practical advantages for random testing and due-cause testing where substantial numbers of the workforce under a testing regime are mobile, geographically dispersed and invariably removed from appropriate facilities to undertake urine drug testing. In this situation, we see that oral fluid testing may reduce delays and inconvenience for both management and workers in random and due-cause testing, as such testing does not need specialised collection facilities and removes any shy bladder or other difficulties in immediately producing a urine sample. However, caveats need to be applied about the institution of oral fluid testing. Firstly, to maintain the credibility of the workplace drug-testing scheme, the level of overt or implicit pre-announcement of testing to an individual must be short, of the order of a few hours maximum. Secondly, the number of UK laboratories with the necessary expertise to both carry out drug analyses in oral fluid and aid in their interpretation is very limited in contrast to those undertaking urine testing. A similar situation exists for the crucial MRO function. Thirdly, the importance of accreditation and the transparency of performance in long-term, independent quality assurance schemes for any laboratory undertaking oral fluid testing needs to be at least equal to that found in the urine drug testing arena. It could be argued that a move to oral fluid testing would be more compatible with the draft guidance given by the Information Commissioner concerning testing for impairment or recent drug use. We feel that this is a much stronger argument for considering drug analysis in hair only in very specialised circumstances. While definite evidence is lacking that appropriately collected urine samples for drug testing is any less acceptable to workforces than other sample types, anecdotal information suggests that some elements of workforces do find urine collections somewhat degrading. This may be for a number of reasons; that it is invariably carried out by external drug testing collection staff rather than by occupational health staff, use of inappropriate toilet facilities or over-zealous behaviour of collection staff in terms of an observed urine collection. Interestingly, much pre-employment drug testing is urine based but within a medical carried out by an occupational health department, and that anecdotally it seems to be readily accepted. We feel that where workforces deemed necessary to undergo due-cause or random testing are largely non-mobile, where appropriate facilities are readily available on- or near-site and there is little complaint from the workforce, there is probably little reason currently for moving from urine to oral fluid testing. We note that both urine and oral fluid samples can be used to accurately predict blood alcohol levels and hence impairment against defined levels for this legal drug. Rehabilitation/treatment is an issue for those who voluntarily declare an alcohol/drugs problem or via disciplinary procedures. However it will likely be infrequent in any single company implementing the Railway Group Standard. Rehabilitation seems possible for many workers, but through a tailored treatment and counselling regime, ix

11 however the ongoing expansion in such services is geared towards more serious chemical dependency. It is unclear to what extent those arranging treatment and followup are able to build on, and help define best practice based on the gathered experiences in railway companies and other safety critical activities where the issues arise from time to time, e.g. road-transport, aviation, nuclear, medical etc. This development of a core, shared expertise in rehabilitation issues within the UK may mirror the key role of Substance Abuse Professional identified by the US Department of Transport as overseeing appropriate treatment and subsequent monitoring within their regulatory framework. Specific technical issues raised from the 2002 ATOC meeting (The specific technical issues raised are italicised in the following section) The issue was raised about the apparent lack of standards and guidelines for oral fluid measurements. This is somewhat countered by the recently published, proposed guidelines by SAMHSA in the USA. Our opinion is that these SAMHSA guidelines are not perfect but, as for urine, they will drive the formulation of agreed, best practise guidelines throughout the world. We would highlight that urine workplace drug testing has been performed without significant challenge for many years, however UK guidelines for legally defensible workplace testing (UKWDTF) have only recently appeared. The adhoc UKWDTF body is currently addressing such guidance for oral fluid. Oral fluid testing has an increasing use in differing settings such as routine workplace testing, rehabilitation clinics and the Home Office Drug Treatment and Testing Orders, such that de-facto guidelines and best practice have largely already evolved based on this considerable experience. The nature of the what is oral fluid (terms used such as OMT/saliva), the mechanism of how drugs enter oral fluid and therefore their relationship to blood drug levels and that some drugs do not readily transfer from the blood into the oral/fluid saliva was presented as an issue. We feel that there has been some confusion in these related areas. Our view is that the diffusive mechanism is important for the entry of many drugs into the mouth, and means that the supposed nature of the oral fluid collected is not a key issue. In practise, almost all oral fluid collection devices will collect a volume of this fluid, derived from various sources, albeit with some minor differences in constituents. For these drugs there will be a good relationship between the drug in an oral fluid sample and that circulating as unbound drug in blood, which potentially influences performance and behaviour. Other drugs or metabolites diffuse more poorly through the mucosal membranes and salivary glands. However, the evidence suggests that even for many of these drugs, oral fluid concentration can be adequately measured to give both reasonable detection windows and define the difference between positive and negative samples. The deposition of some drugs (e.g. THC) on the mucosal membranes of the mouth through smoking or ingestion is very largely the mechanism whereby such drugs are found in oral fluids. Some nasally abused drugs (e.g. cocaine) may well add substantially to x

12 measured oral fluid levels through the mechanism of their deposition in nasooral cavities. Concerns were raised about the relatively small sample of oral fluid that can be collected in comparison to urine, and as Altrix implement concurrent samples (A & B samples) taken from either cheek-gum pocket, is it possible that they could produce different results and thus encourage appeals to be made in cases against an initial positive result? There is scientific evidence for cannabis that the sidedness of the sample collection has no significant effect. We feel that there is no reason why this conclusion should not stand for other drugs. We note that the SAMHSA proposed guidelines also allow for two collections collected almost simultaneously. The volume of oral fluid collections are much smaller than urine collections and would limit the capability for significant number of repeated investigations on the same sample. However, our discussions with three laboratories that undertake such analyses suggest that lack of sample is not a practical problem for undertaking screening and confirmatory analyses. The possibility for ingestion or oral cavity contamination with poppy seeds to give positive opiate results could be problematic for both urine and oral fluid measurements. Some adjustments upward to the SAMHSA urine cut-off for opiates have been made recently to try and obviate positive opiate results from this non-abuse cause. Albeit a small study on a single subject showed that it was unlikely in practice to be a more significant problem for oral fluid compared to urine measurements. The specific metabolite of heroin (6-AM) widely used to further investigate positive urine opiate screening results has also been shown to be applicable in oral fluid testing. Concerns were raised that oral fluid measurements may be currently a little more restricted in the range of drugs detected compared to urine. This may reflect the historical reliance on using urine as a non-invasive sample for drug analysis. However, those standard drugs that are included in workplace testing profiles (e.g. cannabis, cocaine, opiates, morphine, PCP, amphetamines, metamphetamine and ecstasy, barbiturates, benzodiazepines, methadone and Buprenorphine) appear to be covered by routine oral fluid testing techniques. The variable volume of oral fluid collected by the Intercept oral fluid collection device (Altrix) and diluted into a constant volume of transport fluid has been suggested as a possible cause of two problems. Firstly, whether enough oral fluid for a valid test has been collected is unknown until laboratory analysis. Secondly, that it makes the establishment of precise drug concentration levels impossible and therefore obtaining standardised cut-off levels that define test results as positive or negative. Our opinion is that the lack of an indicator of volume collection during the sampling procedure using the Intercept device is not ideal. Also that while IgG measurements in the laboratory indicate that oral fluid is present in the collected sample, it cannot be equated to the interpretation that can be applied to a creatinine measurement in urine sampling. These may not be significant issues if the prevalence of sample collection failures for oral fluid collection is low relative to urine, but the data we have seen on this issue appears contradictory. While samples collected using the Intercept device may involve variable volumes of oral fluid, there appears no obvious evidence that this influences the capability of using this technology to distinguish between xi

13 negative and positive samples using defined cut-off levels. It is a very widely used collection device for drug testing in the US and UK. Concern that parent THC may only be found in oral fluids after cannabis exposure has been raised with regard to passive smoking or cannabis ingestion. At least one controlled small study shows a significant detection window of positive cannabis in oral fluid collections after cannabis-cake ingestion. Recent research has also suggested that a positive oral fluid result following passive cannabis smoking is extremely unlikely in the workplace setting. Concerns on capability of any firms undertaking such alternative drug testing analyses to meet demand from the railway industry both for analysis and sample collection services is outside the scope of this report. Other technical issues which have been raised during discussions or communication with stakeholders within the railway industry, or others involved in applying workplace drug testing are noted below: Concerns were raised about the accuracy of alternative testing media to urine, especially the possibility of an increased level of false positive results. There is a need to be careful that it is not implied that urine testing is the gold standard. The evidence from a large-scale study suggests that the prevalence of positive results from urine and oral fluid testing for a number of drugs is comparable in similar working populations. Drug testing strategies using oral fluid, urine and hair are all comparable in the underlying philosophy of involving screening and confirmatory analyses, the rationale in defining appropriate cut-offs, and other factors which are involved in the process to reduce the likelihood of falsenegatives or false-positives. Therefore, there appears no practical evidence or reason for oral fluid testing to give a significantly higher prevalence of positives results whether detecting true positives - those who have taken the drug or as false positives. That attendance at specialised facilities for urine drug testing by geographically dispersed staff has significant influence on staff rostering and can also lead to considerable pre-announcement of testing for that individual. We were interested to learn in discussion with stakeholders that some staff that undergo urine drug testing in the railway industry may have some idea of a random drug test some 24 hours before testing. This is due to the understandable need to change duty rosters in order to maintain services. Some pre-announcement of testing is caused by the need to get such staff to appropriate facilities to undertake the urine testing. This large time element of pre-testing announcement runs counter to the ideal of random, unannounced testing as an element in a drug testing strategy. Behaviour modification in this period may allow the criticism of manipulation of the test result. Such an extent of pre-announcement for oral fluid testing would be even more unacceptable due to the somewhat shorter window of drug detection in this sampling media. However, there is no reason why oral fluid testing, cannot be applied to workers with a minimum of disruption to their working day or roster, as it needs no special collection facilities. Questions about the level and manner of the random element of a testing strategy as an effective control of drugs and alcohol problem were raised. We xii

14 could find no evidence that defines the most appropriate frequency of random drug testing, but note that the US Department of Transport mandates minimum annual random drug testing rates of between 25%-50%. Our experience is that annual testing rates across UK industries implementing random testing within their workplace drug testing strategies are generally between very low to about 20%. Although higher frequencies are noted in some specific offshore work activities. However, we noted in our discussions with stakeholders that two companies operating public bus services had annual random testing of 5% and 50%. The annual rate of random testing in TOCs appears to be around 5%. Questions were raised about the effectiveness of pre-employment screening. There is not a large or convincing body of published evidence on the effectiveness of pre-employment screening in producing a safer more efficient workplace. This should not be taken as suggesting that pre-employment testing does not make a useful contribution to those goals. We noted comments made by contacts both within and without the railway industry that the prevalence of positive drug and alcohol tests had been relatively high when pre-employment testing was first introduced, but has fallen after it has become established. Our experience is that urine testing is invariably used within UK companies undertaking pre-employment drug testing. An argument has been advanced that as urine testing reflects recent drug usage and is often performed at a prearranged medical, then failing a pre-employment drug test either identifies those with a serious habit who cannot modify their behaviour or those who are not intelligent enough to know how to manipulate their behaviour in order to pass the test. xiii

15 Table of Contents Section Content Page 1 Introduction 1 2 Preamble 5 3 Technical Issues. Part One What substances (drugs) that impair judgement and performance are currently, significantly abused in the UK? 3.2 What sort of workplace substance abuse testing programmes are currently being used both within the UK and internationally, and how does the scope of these programmes map to this substance abuse. What changes in testing programmes are happening? 3.3 What current expert guidance and review of aspects of testing programmes, including sampling media (urine, hair, oral fluids etc.) are available? 3.4 How do drugs and their metabolites get into saliva/oral fluid? What is the evidence that various sampling techniques for collecting oral samples reflect fluids from significantly physiologically distinct origins? Is a particular system for OF collection superior in terms of applicability to drug testing schemes? 3.5 What are the time relationships between detection of drugs in various sampling media- detection window? 3.6 What are the strengths and weaknesses associated with drug analyses in various sampling media? 3.7 What is the susceptibility of the analytical procedures associated with the various sampling media to be deliberately compromised? What confounding factors could lead to false positives in various sampling media? What quality assurance and analytical accreditation schemes are available to ensure the analytical quality of results from any testing strategy? How do they influence the analytical validity and legal defensibility of drug testing results? 55 4 Legal, ethical and Implementation Issues. Part Two How acceptable to workforces are the various sampling media and collection systems and what practical or ethical difficulties can the various sampling systems cause? What is considered best practice in chain of custody procedures? What safeguards are used to guard against false positives that could lead to unwarranted employment consequences 4.4 What is the current UK legal status of workplace drug testing whether carried out as preemployment, due-cause, or random screening? What aspects of drug testing are legally xiv 63 66

16 contested, either on general principle or an individual case basis? Are there any specific legislative changes that may have implications for drug testing in the UK? 5 Rehabilitation strategies and monitoring/testing arrangements. Part Three What have proved to be successful rehabilitation programmes, and what testing or monitoring 72 strategies should be applied to an individual within or after such a rehabilitation programme? How does this compare to the current Group Standard GE/RT/8070? 6 References 78 7 Glossary 92 xv

17 1 INTRODUCTION This report is authored by Peter Akrill and Howard Mason (Health and Safety Laboratory, Sheffield). It is written in response to a competitive tender placed by the RSSB. The original objectives of the tender were: To evaluate common illicit drug sampling and testing methodologies and report on the suitability of each in meeting the requirements of the Railway Group Standard and applicable legislation To examine and report on the applicability of each method to the railway environment, their medical and legal robustness in supporting both disciplinary action and providing confirmation of the effectiveness of rehabilitation strategies. Three phases of the report were envisaged; Phase 1 reviewing the literature involving testing methods for substances that are abused, assessing the strengths and weaknesses of each method, the practical application of each method, a list of substances that are detectable by each method and their effectiveness, window of detection, and other significant criteria. This includes their suitability for pre-employment, random and due-cause /post-incidence testing and monitoring compliance during any rehabilitation period Phase 2 covering the legal robustness of the application of varying testing methodologies and the defensibility of results from drug testing schemes. This phase covers any issues from employment law, human rights and freedom of information issues. Phase 3 was to provide evidence or expert opinion on the suitability of testing strategies within rehabilitation strategies for workers who have an identified drugs and alcohol problem. The original tender specification did not include sweat sampling within a possible drug testing strategy but was included after discussion at the project kick-off meeting. Thus the report covers urine, various types of sample collections from within the mouth, hair, sweat and blood. The tender and initial meeting with RSSB defined that point of collection testing (POCT) was not within the scope of the report; while this may be because of operating procedures within the rail industry, it is difficult these days to review any aspect of workplace drug testing without including POCT. For example, the use of breath alcohol measurements using standardised, commercial apparatus is an example of a widely applied POCT device for one specific drug (e.g. alcohol) that is widely accepted and applied in workplace drug testing strategies (including the rail industry). We have not reviewed the use of POCT within this study, but there are several inescapable references to it within the report. We confirmed at the kick-off meeting with RSSB that the purpose of the report was not to make direct recommendations. 1

18 In order to help us focus and develop the report, we developed sets of inter-related and focussed questions to answer the objectives within the tender. A list of grouped questions was agreed after consultation with RSSB. We hope that this approach may make it easier for the reader to identify specific areas of their interest within the scope of the report, but we acknowledge that this approach may lead to some repetition between sections due to unavoidable overlap. We have found that in carrying out other broad based reviews the use of defined, grouped questions helps focus on important issues within the scope of the review. The approach defined in the tender and discussed at project meetings with RSSB is that the report would be evidence-led where possible. Thus for technical issues we have significantly weighted evidence from peer-reviewed, published scientific papers, where available. Information from other independent reviews, committees and regulatory bodies has also played a significant role. We have also contacted a number of key players within workplace drug testing. Importantly, a number of individuals with significant responsibility for, or interest in, the application of drug testing strategies both within the area of the railway industry and other industries have been approached for their experience and opinions on testing strategies. Thus the report is a mixture of evidentially based facts, personal experience and the opinion of those involved in workplace drug testing, including those within the rail industry. We have attempted to make it clear in the report which is evidential data and which is opinion. A key driver for this report was the outcome of an ATOC meeting of the 14 th May 2002 where the applicability of Altrix s oral fluid drug analysis based on the Intercept oral fluid collection system and trialled at Midland Mainline was discussed. A number of specific and general questions arose directly from this seminar or from discussion and correspondence within industry stakeholders on the applicability of current and possible alternative workplace drug testing systems, based on sampling matrices such as oral fluid. We have attempted to address these issues both within the body of evidence assembled for the agreed questions and explicitly within the executive summary of the report. We have drawn together the various questions, comments and discussion arising from the ATOC seminar into a series of defined issues, which are shown below: the lack of standards and guidelines for oral fluid measurements and concerns about the legal defensibility of such sample collections the nature of the oral fluid sampled as opposed to other terms such as OMT/saliva, the mechanism of how drugs enter oral fluid and therefore their relationship to blood drug levels and that some drugs, such as cannabis and benzodiazepines, do not readily transfer from the blood into the saliva. the relatively small sample of oral fluid that can be collected in comparison to urine. As Altrix implement concurrent samples (A & B samples) taken from either cheek-gum pocket, is it possible that they could produce different results and thus encourage appeals to be made in cases against an initial positive result? poppy seeds found on some food products, and trapped in teeth/gum margins from near where the oral fluid sample is taken, could produce a high and positive opiate result unrelated to opiate abuse, 2

19 oral fluid measurements are more restricted in the range of drugs that can be detected oral fluid collection device (Intercept, Altrix) traps an indeterminate volume of fluid, which may cause two problems. Firstly, it is not known whether enough oral fluid for a valid test has been collected until the sample reaches the laboratory. This may be problematic in for-cause screening when retesting cannot replicate the original conditions. Secondly, that it makes the establishment of precise drug concentration levels impossible and therefore obtaining standardised cut-off levels that define test results as positive or negative, the efficacy of oral fluid measurements, as opposed to urine measurements, in detecting cannabis intake whether by smoking or within food. The reliance of oral fluid cannabis measurements on detecting the parent drug rather than major metabolites in making it difficult to differentiate between active and passive cannabis smoking, the capability of firms undertaking such alternative drug testing analyses to meet demand from the railway industry both for analysis and sample collection services. Other issues which have been raised during discussions or communication with stakeholders within the railway industry, or others involved in applying workplace drug testing are noted below: concerns about who runs any drug testing scheme, whether occupational health department, human resources department or within direct line management of the employers, concerns about the accuracy of alternative testing media to urine, especially the possibility of an increased level of false positive results, that urine testing is degrading to those undergoing testing, that attendance at specialised facilities for urine drug testing by geographically dispersed staff has significant influence on staff rostering and can lead to considerable pre-announcement of testing for that individual, concerns about the level and manner of the random element of a testing strategy as an effective control of drugs and alcohol problems about the effectiveness of pre-employment screening. the role of MRO within workplace drug testing schemes and the training and competency of those undertaking an MRO role. The report is constructed in three sections, with some slight modifications as described earlier. The first section, dealing with technical issues about drug testing, being the largest section covering some 8 out of the 11 agreed question areas. It is very largely based on published scientific peer-reviewed papers. The second section deals with legal, ethical and implementation issues that may surround workplace drug testing in general and the specific testing methods described in section 1. As noted in the HSL tender document, by the completion of sections 1 & 2 the report should identify optimum, legally defensible testing method(s) for use in the different situations arising on the UK railway system, and identify any areas where technical and legal problems may 3

20 potentially be encountered. Section 3 covers testing or monitoring arrangements within rehabilitation strategies. Each question or set of questions is followed by a bulleted summary. A more detailed commentary, including tables where appropriate, is included to substantiate our summary responses to the questions. An executive summary, which rolls up the responses to the individual questions in answering the defined objectives of the project, precedes the main body of the report. 4

21 2 PREAMBLE Workplace drug testing in the UK and Europe is largely being carried out in those industries where it is recognised that there is a significant safety critical element within areas of the firm s activities. This includes transport (road, rail and air), but also other industries such as construction/demolition, major hazard installations e.g. petrochemical works, power generation etc. A number of companies with high public profiles, including a number of financial institutions, also carry out some workplace drug testing. The most common form of drug testing appears to be related to pre-employment testing. Many firms within various industry sectors will view the rationale for drug testing within an overall substance abuse policy and against a range of legal and regulatory frameworks. These include standard health and safety legislation in terms of the responsibilities for employers & employees in terms of the risk of an abuser s behaviour to themselves and others, the Road Traffic Act (1988), Misuse of Drugs Act (1971) and their associated amendments. We acknowledge that the Transport and Works Act (1992) places specific duties on railways and other guided transport systems to show due diligence in trying to prevent relevant employees working whilst unfit through drink or drugs, and that those companies with relevant railway safety cases must comply with the relevant, current Group Standard concerning drugs and alcohol (GE/RT/8070). The use of drug testing in addition to the implementation of an appropriate Substance Abuse Policy within a company should be derived from a risk analysis of the particular organisation and its activities, and conforms to the appropriate legislation mentioned above. This needs to be set against a background that methodologically strong evidence for drug testing per se to have an effect on accident reduction and improvement in performance, appears to be lacking (see section 2) and that there is considerable debate about this issue. Drug testing (pre-employment and random testing) is acknowledged not necessarily to be an efficient means of identifying drug users. Random testing has been described as an effective means of both intervening with heavy users and discouraging casual users, the frequency of such random testing will influence its efficacy. Pre-employment testing is essentially about trying to exclude users from the workplace. There has been considerable international debate about issues of the legality and ethicality of aspects of drug testing programmes. There are a number of recent signal publications or activities, which have been useful in undertaking this review. These include: The new, proposed guidelines for US federal employee testing from SAMHSA, an independent regulatory body that has had substantial influence on workplace drug testing worldwide over the years. These guidelines should not be considered as perfect or necessarily appropriate for the UK, and are currently only proposals, but they are a signal event in terms of alternatives to urine testing being given some authoritative independent stamp of acceptance after 5