When goalkeeper Lewis Maguire was diagnosed with Hodgkin lymphoma, he was forced to abandon a dream trial with Leeds United.

The 15-year-old fitness fanatic had been suffering night sweats and tiredness for three months – and then a growth on his neck sounded the alarm.

His father, Nigel, 61, remembers: ‘Lewis’s initial treatment involved chemotherapy and steroids. He managed well, even though he experienced sickness and significant weight gain due to the steroids. Lewis remained calm, and I focused on the practical side, ensuring he reached the hospital.’

Hodgkin lymphoma is extremely uncommon in children, with only about 60 cases diagnosed annually in the UK, as reported by the charity Children With Cancer UK.

Since the early ’90s, the rate of lymphoma and other blood cancers in children has increased by 39.7% in those under 15, and by 25.2% in young people aged 15 to 24.

And scientists, campaigners and public health experts suggest the increasing use of artificial pitches may help explain the rise.

Two years post-treatment, Lewis watched a TV program discussing a potential link, focusing on football coach Amy Griffin, who had developed a registry that highlighted a connection between goalkeepers and blood cancers.

The program particularly mentioned concerns about ‘rubber crumb’, small particles from recycled tyres used to cushion artificial football and rugby pitches.

‘Lewis said, “Hey, that’s me!”‘ recalls Nigel, a former chief executive for NHS Cumbria. ‘As a goalkeeper, he would get grazes that would be black and the rubber crumb would be in his clothes. He’d rub it in his eyes, he’d swallow the stuff.’

Lewis raised this possible link with his consultant, who ‘couldn’t say there was definitely a link as there was no evidence base, but said it was worth exploring the possibility’, says Nigel.

Tragically, Lewis succumbed to the cancer in 2018 at the age of 20. An inquest into his death, which is routine for someone so young, concluded that he died of natural causes and multi-organ failure owing to cancer treatment, despite the family’s concerns about a link with artificial pitches, and the world moved on.

That same year, the Football Association announced a major increase in funding for grassroots facilities and schools, including artificial pitches and playgrounds.

There are now 3,013 full-size and 4,419 mini artificial football pitches in England alone, according to a parliamentary answer last year.

Scotland has an estimated 300 full-size and 1,000 mini pitches; Wales has around 100 artificial pitches.

Their appeal is clear: unlike grass, they can be used year-round, require less maintenance and are good value for money. And for cash-strapped local authorities, schools and colleges, the lure of long-term savings and grants is undeniable.

The Football Foundation, Sport England and the National Lottery all provide grants for artificial pitches, and in March, Culture Secretary Lisa Nandy announced a £100million upgrade in sports facilities, including artificial pitches. But as the football season begins and the new school term starts, just how safe are artificial pitches containing rubber crumb?

These 3G artificial pitches, as they’re known, are in essence a plastic layer cake, consisting of a gravel, asphalt or concrete base, topped with a shock-absorbing layer. Next comes an anchor layer holding ‘grass’ blades made from plastic such as nylon, polypropylene or polyethylene.

And finally comes the ‘infill’ between the grass blades, which consists of recycled tyre particles called rubber crumb. This is different from AstroTurf, a brand name for an earlier type of artificial pitch that is filled with sand.

Rubber crumb (like the ‘grass’ blades) is a type of microplastic, according to the European Union. Rubber crumb is also known to contain PFAS chemicals – or ‘forever chemicals’.

These have been linked to a range of health problems, including reduced immunity, raised cholesterol, thyroid problems and some cancers including lymphomas and leukaemia.

Two years ago, the European Commission announced that the sale of rubber crumb infill would be banned from 2031 because, as a microplastic, it poses environmental and health risks.

In the UK, however, the Government has yet to decide on whether to follow the EU’s lead.

But the evidence against the use of these pitches is mounting.

A report by the Department for Environment, Food & Rural Affairs (Defra) earlier this year revealed that artificial pitches were the largest source in the environment of deliberately added microplastics.

It stated: ‘Early findings suggest that [they]… may create harmful… reactions in the body and interfere with how cells work and stay healthy.’

It is assessing the next steps in light of the report.

But for some experts, there is no ambiguity: rubber crumb should be banned immediately.

As Andrew Watterson, a professor of health effectiveness at Stirling University and a leading expert on artificial pitches, told Good Health: ‘Microplastics cannot be fully contained within pitches and playgrounds – and there is growing evidence of potentially serious health effects.

‘By the year and almost by the month more and more concerns have been raised, with research documenting the risks of various materials and chemicals used in microplastics.’

Professor Watterson points to a review by Harvard University in 2023 that detected potentially harmful microplastics ‘throughout the human body’.

This report, which analysed existing research, found some microplastics can infiltrate human cells and there is evidence that they can damage DNA and change gene activity, the precursors to cancer.

Last year a report for the US Environmental Protection Agency on the impact of rubber tyres, including rubber crumb used in artificial pitches, concluded that crumb production could release chemicals and heavy metals.

As well as an incoming ban on rubber crumb infill, the EU has reduced the permissible level of toxic and carcinogenic chemicals – polycyclic aromatic hydrocarbons (PAHs, which are used in the production of tyres) – in rubber crumb to 20mg per kilo.

Professor Vasilis Vasiliou, a public health scientist at Yale University who has researched this issue, believes that the risks to children are manifold. 

‘My major concern is not only the carcinogens, but also the volatile organic chemicals – such as benzene – which can easily turn into a vapour and be inhaled,’ he says. ‘Some of these chemicals are phthalates, which are neurotoxic.’

He suggests these could affect the IQ of children.

Last year Professor Vasiliou and Professor Watterson were co-authors on a study that backed the EU ban on rubber crumb and advocated that other nations should follow suit.

They wrote: ‘Such infill has been demonstrated to contain hundreds of chemical agents with potentially adverse health effects.’

Professor Vasiliou’s concerns are personal, as a close friend of his daughter developed hot skin lymphoma, a rare type of non-Hodgkin lymphoma that causes skin to feel like it is burning. The child had played on 3G pitches.

‘When my children were little they played on these pitches with no protection and when I found out, I pulled them off,’ he says.

‘I said to the coach, “You should have told me this was artificial turf”, and the coach said, “Oh, you are an activist.”

‘But I’m not an activist – I am a scientist and a public health practitioner. I don’t want to spread fear. I want people to be informed.

‘Personally, if it is artificial turf with crumb rubber, I would avoid it. What we need is to abide by precautionary principles.’

But critics of the crumb are limited by the fact that there are no long-term epidemiological studies to track the health of children using rubber crumb pitches.

Professor Vasiliou thinks he knows why this is: a study he proposed on the exposure of university athletes to rubber crumb was turned down because, he suggests, ‘if all these students are getting carcinogens in their blood, then the university could become liable to lawsuits. 

‘I tried many universities but nobody would agree to let us do the research’.

Meanwhile, those who support the use of artificial turf point to this very lack of long-term studies to double down on the official line that there are no health risks.

Both Fifa and Sport England cite a 2017 report into rubber crumb by the European Chemicals Agency (ECHA) which said there were no significant health concerns for players, and that concentrations of substances such as PAHs were below levels that would typically lead to health risks.

But the ECHA also recommended players ‘wash their hands’, do not swallow rubber crumb, and remove clothes and shoes outside.

While the EU has set a legally binding limit of 20mg/kg for PAHs, the UK government rejected this as unnecessary because it argued most rubber crumb was already below this level. Instead, a voluntary limit of 20mg/kg was introduced by the industry body, the Sports and Play Construction Association.

But George Tranter, a fellow of the Royal Society of Chemistry, says: ‘Even 20mg is more lax than other materials with PAHs that come into contact with human skin and the human body. With a tennis ball or a rubber tile you’re talking about only 1mg per kilo being permissible for human contact. Why is rubber crumb allowed to have much higher concentrations when it also comes into contact with the human body?’

He believes that the current safety regulations fail to take into account that rubber crumb generates a lot of dust.

‘Dust is considered in these regulations, but the levels accepted that might occur in football pitches have their flaws,’ he says.

One issue is that the values are derived from a Norwegian study where they used an indoor pitch for a more controlled environment – ‘they put the measuring devices outside the pitch, because they did not want to interfere with the activities – but the dust is generated on the pitch,’ he argues.

‘The second issue is they do not mention what height the measurements were taken from. The pictures suggest they were at adult chest height. That is a problem because a lot of the dust comes from when a player falls on the ground.

‘And what about a child or a rugby player [who falls down] or a goalkeeper? They would likely have the highest exposure to dust.

‘So we are underestimating the exposure to PAHs and are not accounting for children.’

Professor Vasiliou also points to the influence of the artificial turf industry.

Earlier this year artificial turf maker Polyloom launched a lawsuit against four US experts ahead of a seminar on the health risks of playgrounds and sports fields. One of those experts, Kyla Bennett, Director of Science at US pressure group Public Employees for Environmental Responsibility, conducted a study in 2024 that found that after children played on artificial turf, 75 per cent had higher levels of PFAS ‘forever chemicals’ on their skin than before.

Kyla Bennett told Good Health: ‘I was one of two scientists who discovered PFAS in artificial turf back in 2019 and since then I have been a loud opponent.

‘We were sued for defamation before we even had the webinar – and we were sued in our personal capacities. The whole thing is disturbing and is clearly meant to chill speech around this topic.’

Along with a medical professor and two US environmental group directors, Kyla Bennett has hit back with what is called a Slapp suit, accusing the company of trying to intimidate and silence. Polyloom parent company TenCate did not respond to the Daily Mail’s requests for comment.

There is no doubt that the financial stakes in all this are considerable. In 2024 the global market for artificial turf was put at $6.87billion (£5.1billion)and it was projected to grow to $9.97billion (£7.4billion) by 2030, according to Grand View Research.

George Tranter says: ‘There is an economic argument that there are a lot of spare tyres out there and this is a good way of getting rid of them. So the safety aspects are minimised.’

In the UK, sports and government bodies insist there is no evidence that artificial pitches pose a danger to the long-term health of the millions of people who use them.

A Fifa spokesman said that artificial turf ‘helps bring football to millions of people’ when natural pitches are impractical.

He said that studies ‘have assessed the use of [rubber crumb] in artificial turf – and have found no reason against playing on such a surface’.

A Defra spokesman said: ‘We are committed to protecting human health and the environment from the risks posed by microplastics, and are working closely with the sports sector.’

A spokesman for industry body the Sports and Play Construction Association acknowledged the difficulty ‘in trying to balance the health and wellbeing benefits that come from the use of 3G pitches with environmental sustainability factors.

‘However, it is important to note that there are currently no widely available alternative infill products with proven durability… that are as suitable for all UK weather and deliver the required performance standards. We will continue to research and reduce the spread of microplastics into the environment.’

These assurances cut little ice with the Maguire family.

Nigel believes that the increase in childhood lymphomas and leukaemia over the past 20 years should at least raise questions about the causes.

‘I am not silly enough to say that Lewis died simply because he was exposed to shredded tyres – but there is clearly a risk.

‘You only have to look at studies on the long-term exposure to carcinogens to know people are susceptible to them. My point is, we should take the precautionary principle when it comes to our children and our health. An absence of evidence is not evidence of absence.

‘We should not be allowing our kids to be playing on this stuff.’