Contributed Commentary by Darren Rowles
May 3, 2019 | The world is in the grip of a panic over plastic pollution, with news headlines proclaiming a global "catastrophe", "calamity" and "crisis" over the effect our growing use of the material is having on the environment.
Plastic is one of the most durable, versatile and ubiquitous manmade materials, with countless applications in our daily lives. However, it is also extremely long-lasting, taking more than 400 years to degrade, which means most of the 8.3 billion metric tons produced since the 1950s still exists in some form; only 12% has been incinerated and roughly 79% has accumulated in either landfill or the natural environment. What's worse, it is estimated that between 4.8 and 12.7 million tons of waste plastic enter the oceans each year, which has a devastating impact on marine life through ingestion, entanglement and damage to natural habitats.
Thanks to some high-profile campaigning in recent years, awareness of the issue is high and action is being taken by governments and businesses across the world to reduce consumption of single-use plastics, including schemes to replace or remove plastics in our everyday lives, such as in carrier bags, food packaging and drinking straws. However, despite these efforts, global plastic production is still set to quadruple by 2050.
At this point you might be wondering why I, the CEO of a life sciences company, am writing about plastic pollution in a publication dedicated to diagnostics. Well it is because I strongly believe that the diagnostics sector has a responsibility to look at itself and make some tough decisions over its own use of plastic.
For the last 16 years I have worked in the field of lateral flow rapid point of care diagnostics. Lateral flow tests, also known as lateral flow immunoassays, are a fairly simple diagnostic technology, consisting of a paper-based test strip with a sample pad, a conjugate pad and one or more test lines.
The basic test format is a "dipstick" type, but the majority of tests produced are contained within a plastic housing. These low-cost cassettes, fabricated with injection moulding, typically consist of two pieces that snap together with a sample port and a reaction window allowing the test and control portions of the strip to be seen.
The problem is that lateral flow is a "throwaway technology", with most tests manufactured being single use and non-recyclable. Most will be incinerated along with other medical waste but many will still end up in landfill.
They are also very easy to make and extremely popular; more than 2 billion lateral flow assays are produced each year, including more than 400 million a year each for malaria and HIV tests. Perhaps the most well-known application of lateral flow technology—and the use that drove the early development of the technology—is the home pregnancy test. In the US alone, some 20 million pregnancy tests are sold each year.
What's more, the lateral flow market is growing rapidly, fuelled by factors such as the high prevalence of infectious diseases across the globe, rapidly increasing geriatric populations, increasing usage of home testing, and growing demand for point-of-care test devices. Worth an estimated $6 billion in 2018, the lateral flow market is projected to reach $8.7 billion in 2023.
So, with hundreds of millions of tests produced and sold every year and demand for point of care testing set to grow, the potential amount of non-recyclable plastic waste produced by this one small market segment alone is significant.
I believe that lateral flow test developers and manufacturers have a duty to reduce plastic waste by rethinking how they make tests and coming up with innovative new ideas.
One way is to turn two or more tests into one through the use of multiplexing – having more than one test line on a strip – which allows users to detect multiple targets. For example, in human and animal health diagnostics, multiplexed tests can be used to detect more than one disease, while in agricultural, environmental and food testing they can be used to confirm the presence of multiple contaminants. In all scenarios they negate the need for many separate individual tests. The industry is only just starting to explore the potential of multiplexing, but I think this must be accelerated.
We also need to look at using different materials. For example, can we make reusable plastic cartridges, or even paper-based housings that can be recycled? One company pioneering the use of alternative materials is US-based startup Lia, which recently hit the headlines for producing the world’s first flushable and biodegradable pregnancy test. The test is made from the same non-woven natural plant fibres as toilet paper, and like toilet paper, it breaks down when flushed.
Co-founder Anna Couturier Simpson said the test contains "zero glass fibres, batteries, plastic or nitrocellulose—elements found in nearly all single-use diagnostics available on the market today."
I know reducing plastic use in the diagnostics industry is not going to be easy; it's going to take a lot of hard work and effort from a lot of different people and it's not going to happen overnight. Test developers and manufacturers are going to have to change their mindsets, overcome their differences and work together to figure out new manufacturing methods and other innovative ideas if we are to succeed in cutting the plastic burden.
Not only will this be good for the industry, spurring on the next generation of lateral flow test development, but most importantly it will also be good for the planet. The plastic problem has already been diagnosed; now diagnostic companies must come up with the solution.
Darren Rowles is CEO and president of Sona Nanotech, a life sciences company based in Nova Scotia, Canada, which produces unique gold nanorods for use in next generation diagnostic tests and medical applications. Rowles has 16 years' experience in product manufacture and development in the area of gold nanoparticles and lateral flow diagnostics. He can be reached at email@example.com.