Solvent-induced Neurotoxicity

Reproduced with permission from Safeguard magazine.

Aucklander David Duke used to leave work in a state of bliss. He’d walk from work to the bus stop marvelling at the trees and the sky and the clouds, feeling wonderful.

Duke was stoned. Not on illicit drugs or alcohol, but on the solvent vapours he was breathing in the course of his work as a screen printer.

These days Duke suffers from such crippling headaches it takes him 20 minutes to psych himself up to lift his head off the pillow. His partner Helen talks of his “wicked” mood swings - affectionate one moment, then threatening to pack his bags and leave the next. Minor irritations provoke unwarranted reactions. Duke himself believes his violent mood swings have cost him several relationships over the years.

His memory is affected too. He forgets what he was about to say or what he went into a room to get. He’ll come off the phone only to forget who he was just speaking to. In recent months he’s noticed himself becoming clumsy and uncoordinated at work, dropping things and struggling with small tasks like fitting the ink knife into the rim of the tin.

For the 14 years of his career as a screen printer, Duke has been exposed to a daily cocktail of solvents, often in factories with little or no ventilation, with little or inadequate personal protection (like the household rubber gloves which disintegrated on impact with the chemicals).

Not that he had any idea that the chemicals so integral to his trade may have been compromising his health, other than a vague feeling that “this stuff stinks and it’s making me spin out.”

Now it appears likely that those chemicals will cost him his trade. He has suspected solvent-induced neurotoxicity, a condition brought on by years of cumulative exposure to organic solvents. His GP has told him he looks like a textbook case, and he has recently been put through a raft of neuropsychological tests to assess such functions as short-term memory, reaction time, attention span and ability to learn new material, which will help determine with reasonable certainty whether his ill-health is indeed a result of solvent-induced neurotoxicity.

A rising epidemic

It’s been estimated that 100,000 New Zealand workers are regularly exposed to organic solvents in the course of their work.

Few industries are entirely free of these extraordinarily useful chemicals. They are used in a diverse range of industries, including boatbuilding, joinery, shoemaking, dry cleaning, painting and plastics. They are used to thin, dissolve and clean a wide range of other substances, such as oils, fats, resins and paints. They are present in paints and paint strippers, glues, inks, dyes, textiles, agricultural products and pharmaceuticals.

Many are highly volatile, evaporating readily at room temperature. Many are highly toxic, and can enter the human body both through the lungs and the skin.

The head of Worksafe Australia’s professional education programme, Professor Wai-on Phoon, recently predicted an epidemic of solvent-induced illness of similar proportions to OOS and asbestos-related diseases.

That prediction may sound sensationalist, but it is a fact nonetheless that workers in New Zealand are falling ill as a result of years of solvent exposure. OSH’s Notifiable Occupational Disease (NODS) Register has the case notes of 222 workers with suspected solvent-induced neurotoxicity. Of these, 157 have been referred to a specialist OSH panel for review. So far, 42 of the 157 have been confirmed as having chronic solvent-induced neurotoxicity.

The list of 42 includes eight printers, three boat builders and two dry cleaners, as well as paint retailers, a chemical worker, an aircraft maintenance worker, a sailmaker, a shoemaker, a vinyl layer, a scotchguard applicator, and a caretaker. Nineteen of the 42 are from the panelbeating and spray painting industry - by far the largest single group on the list.

All of the workers affected have been exposed to organic solvents for several years. The average length of exposure is 18 years, and although the range is from four to 35 years, only four workers have had exposure history of less than nine years. Forty of the workers are men and two are women.

All 42 have been diagnosed according to an international classification system as having Type 2B neurotoxicity. What this means in plain language is that they not only have overt symptoms such as fatigue, irritability and mood swings, but also impaired brain functioning as measured by neuropsychological testing. They will have memory, concentration and coordination difficulties, and their ability to learn new material will be damaged.

If the international research is any guide, some of them will not recover, even after their exposure to solvents ceases.

As with many occupational disorders, these symptoms are often invisible to all but those closest to the victim. The worker isn’t physically maimed, there are no scars or artificial limbs or wheelchairs to underscore the physician’s diagnosis. It’s tempting to write off the victim of neurotoxicity as a mere malingerer.

But that cynical conclusion ignores the intensity and pervasiveness of the symptoms. Stress may make even the best of us tired and grumpy and irritable with the kids, but once the stress comes off we’re OK again.

Not so the sufferer of neurotoxicity, who will experience a long-term deterioration that attacks the quality of life and relationships, and undermines the ability to cope with stress.

Devastating symptoms

Dr Evan Dryson, OSH Northern Region medical officer and chair of the specialist panel reviewing the neurotoxicity cases referred to in the NODS Register, says the symptoms can be devastating to the lives of sufferers. “Loss of memory, mood changes, in-coordination, inability to plan - these are caused by diffuse injury to the brain and they are intensely disabling and destructive to people’s lives.”

They are insidious symptoms that creep up slowly on the victim, with the worker often totally unaware that his or her exposure to solvents may be the cause.

The onset of chronic neurotoxicity is described as follows. “Initially the symptoms may disappear over weekends and holidays, but over a period encompassing years they will become chronic. In the end they will typically be perceived by the individual as a fundamental change in personality.

“Patients will complain about their inability to work, to participate in social activities, to function sexually and to manage relationships. They do not remember what to bring or where to go. They stop participating in organised activities and playing music or cards or doing any other hobby they used to like and in which they may have been skilful. In many cases they are accompanied to the physician by a spouse because they have severe memory deficiencies and because they are afraid.” [Source: Rosenstock L and Cullen M (eds). Textbook of Clinical Occupational and Environmental Medicine. W.B.Saunders & Co, 1994, p.774]

Dryson says marriage breakup appears to be more common among suffers, though there are no figures to confirm that. However, Dr Jenni Ogden of Auckland University’s Department of Psychology has observed that many workers suffering from neurotoxicity seek help only in response to a crisis at work or in their marriage arising from their changed personality, extreme fatigue and memory problems, rather than from any specific concern about the effects of the solvents they are working with.

In many cases workers have already been prescribed anti-depressants or sleeping pills by GPs who’ve failed to make the link with the workplace. Some swallow multi-vitamins in the hope they will act as a pick-me-up. Safeguard was even told of one factory where workers were taking anti-histamines to help them breathe in the solvent-laden air, but which were then making them fall asleep on the job.

Because of the insidious nature of the symptoms and lack of awareness among workers, Dryson believes the cases reported to the NODS represent just the tip of a much larger iceberg, and that there are many more workers with neurotoxicity who have not been identified.

Levels of exposure

So what of the workplaces that these 42 confirmed cases of neurotoxicity have come from? As part of the process of reviewing each case, OSH hygienists made an assessment of the level of exposure to which the worker had been subjected. In many cases this was based largely on an interview with the worker; in some cases historical data measuring the level of solvent fumes in the atmosphere was available.

The conclusion drawn was that the workers had not been employed in Dickensian sweatshops. In the case of the 19 spraypainters - by far the most significant group on the list - Dryson describes their workplaces as “pretty much typical of New Zealand spray paint shops.”

Set against the Workplace Exposure Standards (WES) - the guidelines published by OSH aimed at defining the limits for airborne substances in the workplace - Dryson says the levels of solvent exposure were “not excessive”. He says the panel started out with the expectation that sufferers would be from workplaces with exceptionally high levels of exposure, but by and large workplaces are not exceeding the WES. “In our opinion people are being affected in New Zealand at levels below the WES.”

It is impossible to rule out the possibility that the workers were affected as a result of much higher levels of exposure in previous years, when less was known about the damaging effects of solvents. But equally likely is that the sum total of their exposure over many years has resulted in their condition.

Dryson’s view that workers are being affected at levels below the WES has major implications for employers who see the WES as a near dividing line between safe and unsafe practice.

It also gives renewed fuel to the view within OSH that the significance of the WES should be toned down and employers encouraged to aim for the absolute goals of elimination, isolation and minimisation of the hazard.

“The aim has to be to get the lowest possible level of exposure,” says OSH senior occupational hygienist Andrea Eng. “Theoretically the only safe level of exposure is no exposure, because the WES may protect the majority of people but they won’t protect everybody.”

Despite the confirmation of 42 cases of neurotoxicity now in front of OSH, there is no suggestion of any employers being prosecuted. Ironically, because of the inherent difficulties of proving an absolute causal link between the chemical exposure and the eventual ill-health, OSH operations manager Geoff Wilson believes the WES would be taken as the standard in any potential prosecution.

The other inherent difficulty in prosecuting such cases is the gradual onset of neurotoxicity, with workers likely to have been exposed in a number of workplaces. In such instances, which particular employer could be held culpable?

The 42 workers registered with the NODS represent relatively advanced cases of neurotoxicity. Below that level again are workers who display less severe symptoms and who are likely to fully recover when they leave the job or strictly control their exposure.

Christchurch occupational physician and OSH medical adviser Dr Bill Glass sees many such cases. These are the workers who may experience a range of overt symptoms such as moodiness, feelings of intoxication at the end of the day, tiredness, diminished work performance, and intolerance to alcohol, but whose condition is not considered chronic and who often recover over the weekends and holidays.

It’s impossible to know how many such cases come to light each year. Although ACC accepts chemical poisoning claims on their merits, it has no statistical category for solvent-induced neurotoxicity and was unable to provide Safeguard with a figure.

Glass says that while in such cases there may be no long-term damage done, the impact on the worker and his family while they are experiencing the symptoms can nevertheless be disastrous. He likens the effect on family and work to alcoholism - “except solvents are more toxic”.

He says the families of such workers, who have to come to live with the bad tempers and irritability of their husbands and fathers, sometimes comment on the radical improvement once the worker leaves the job or retires.

Worker understanding ‘almost non-existent’

Despite the mounting evidence in recent years of the health risk posed by solvents, Ron Halewood, health coordinator for the Printing, Packaging and Media union, believes worker understanding of solvents is still “almost non-existent”.

Workers commonly have no knowledge of the chemical makeup of the solvents they work with every day, identifying only with the trade name of the product. Employers’ knowledge isn’t much better, and the situation is made worse by the fact that management of health and safety in many workplaces is “fragile”, with inadequate support and training given to health and safety representatives.

“Workers have a notion that chemicals endanger their health,” says Engineers Union health and safety coordinator Hazel Armstrong, “but they don’t specifically know how, or what quantities or length of duration they would have to be exposed. And very few employers go that next step to monitoring the air quality and then getting that information to staff.

“The majority of workers that I come across are aware that there is a fume or a dust in the air, but they don’t know exactly what is the component of that fume and nor, upon enquiry, does the employer.” She says in the absence of any regular monitoring of exposure levels, “the reality is that we don’t actually know what’s going on.” Regular monitoring, she believes, should be mandatory, and more effort made to ensure material safety data sheets are both available and understandable to workers.

She notes there has never been a prosecution in the area of chemical poisoning, and says until there is, the general statutory requirements such as the provision of ventilation and clean air will be “meaningless”.

Armstrong says to a large extent the problem of solvent-related illness has been concealed from unions because workers often don’t see the link between their ill-health and the workplace. “Because it’s crept up on them slowly they don’t see it as a union issue.”

The macho Kiwi male syndrome may also have a lot to answer for. David Duke talks of a “she’ll be right” attitude during his years as a screenprinter. Anyone who complained of the fumes or the chemical smell was labelled a “wuss and a blouse”. He says workers also resist wearing personal protection such as respirators because they are restrictive and uncomfortable, and perceived as an impediment to the job.

Employer ignorance

Industry leaders admit employers are often as ignorant as the workers. Warren Johnson, chief executive of Printing Industries New Zealand, believes the level of knowledge in the workplace has improved significantly, but in some areas there is an unwillingness to face up to the problem.

“A large part of the management structure of any industry is trade-based management. They come out of the industry and their attitude is ‘I’m 50, I’ve worked in the trade for 30 years and it hasn’t killed me, so therefore it ain’t a problem’.

“I can assure you that that philosophy does exist, and that’s what you’ve got to work on. What you have to do is start working on people as they come into the system.

“If you put yourself in the position of Mr Four-Man Printing Shop in Alexandra, what does he know about Workplace Exposure Standards? The quick answer is - nothing. His printing factory stinks, but so does everyone else’s. He’s never had his place monitored, and he wouldn’t know what you were talking about. It isn’t that he doesn’t care. It’s just that he’s uneducated.”

However, Johnson says in the last two to four years attitudes have changed. “I think the rank and file Kiwi used to think you had to have major doses of chemicals to impair somebody, but now people are realising that severe harm can be caused by drip feeding.”

Nevertheless, he estimates that workers in as few as a quarter of all printing companies are using personal protection to any significant degree. “Respirators are still a rarity. People are still commonly using bib overalls with nothing underneath. And gloves are still used primarily to keep hands clean rather than for safety.”

He says probably only 20 percent of companies have extraction systems to remove vapours from the workplace, and no more than 20 of his organisation’s 500 members would have ever had any atmospheric monitoring done.

Tim Lambert, chief executive of the Motor Body Builders Association, which represents the panelbeating industry, is not surprised workers from his industry dominate the confirmed cases of neurotoxicity on the NODS register. He attributes the problem largely to the “back yarders” - small panelbeating shops which don’t have a spray/bake booth and use spray paints in the open workshop, and which lack a properly ventilated paint mixing room.

He estimates up to 2500 workers in this industry are involved in the spraying and wiping down of cars with solvent-based products. Based on his estimate that 60 percent of shops are spraying in the open workshop, it seems reasonable to conclude that more than 1500 workers could be at risk of excessive solvent exposure in that industry alone.

He says the situation is not helped by the artificial market in which his industry operates, whereby insurance companies effectively cap the amount panelbeaters are able to charge for repairs. For many operators, that’s seen as an excuse not to invest in the capital equipment needed to bring their businesses up to scratch.

Environmental specialist Paul Heveldt of Royds Consulting believes that although there’s been an improvement in workplace standards, there’s still a long way to go. “As a generalisation you could say that the gross problems are by and large taken care of. People are aware that you need to limit exposures, but having said that, people don’t seem to be particularly concerned to reduce exposures to the lowest practicable level. If they can reduce exposures to, say, below the WES, they will be satisfied with that.”

Some areas of industry are attempting to put their house in order. Toyota New Zealand’s Christchurch plant, for instance, actively aims to minimise solvent exposure to the lowest possible level. The hazards surrounding solvents are drummed into the workers and regular monitoring is done to check vapour levels in the atmosphere.

Manders Ink in Auckland, the country’s largest supplier to the printing industry, has moved away from a number of solvents targeted for elimination by the Printing Industry Health and Safety Society, including methylene chloride, toluene, xylene, benzene, methyl ethyl ketone, and glycol ethers. Technical manager Fred Crook says there has been a move towards wash-up products based on vegetable oils and citrus extracts, and customer wanting to buy any of the ‘nasties’ are sent elsewhere.

But he says the alternative products are more expensive and less efficient that those based on organic solvents, deterring many printers from making the switch.

Stemming the tide

So how to stem the tide of this ‘new asbestos’? What should industry be doing to protect its employees from the destructive effects of solvents?

Bill Glass, after years of campaigning for greater recognition of the solvent hazard, is clear as to what needs to be done.

. Greater awareness among workers and employers of the hazards and the symptoms.
. Regular medical surveillance and greater use of biological monitoring tools such as worker blood tests. (Blood tests give a reading of the worker’s actual uptake of solvents - unlike air monitoring which takes no account of skin absorption.)
. Greater use of local and general ventilation systems, and properly fitted body and respiratory protection.
. Substitution of solvents where possible.
. Greater use of questionnaires to establish whether workers are experiencing symptoms.

It’s taken 14 years as a screen printer and the cruel reality of ill health to make David Duke aware of the hazards of solvents. He’s now got a pretty clear idea of the importance of things like clean air and respirators and the right sort of gloves.

How many more cases like Duke’s will there have to be before the 100,000 workers exposed to solvents can really be considered safe?

Reproduced with permission from Safeguard magazine.