Microplastics are defined as any plastic below 5mm in size. They are separated into 2 types, primary and secondary microplastics.
Primary microplastics are below 5mm when they enter the environment, such as nurdles and those found in face scrubs and toothpastes. Secondary microplastics are larger than 5mm when they enter the environment but, 随着时间的推移, 分解成更小的碎片, 比如塑料袋和瓶子的碎片.
Airborne plastics are much smaller particles that are light enough to be carried in the air. Most airborne microplastics are below 1mm in length and are categorised by shape as fibres (long and thin) and non-fibres.
Unfortunately not that much, but we do know that airborne microplastics are found everywhere. They have been found in every place that has been sampled so far. 受影响的不仅仅是城市. Airborne microplastics have been found in remote mountain ranges, the arctic and even sea spray.
Most research on microplastics has focussed on plastics in water. Airborne microplastics is a relatively new but rapidly growing area of research. Those studies that have examined microplastics in the air have been undertaken outdoors. In the UK, however, 90% of our time is spent indoors. Most of the air we breathe is therefore indoor air, yet very little research has taken place on microplastics indoors.
That is why the University has begun research in this area. We are measuring microplastics in different indoor environments, 看类型, 塑料的大小和形状. 尽管数据非常少, what we know so far is that the concentration of microplastics indoors is much higher than the concentration outdoors. Some studies have shown that it is 60 times higher than outdoors, while other research points to an even higher concentration!
目前最好的足彩app只是还不知道. Airborne microplastics research is in its infancy and there are many factors to consider. That is what we are doing now — devising studies to see if there is an impact on human health.
Some studies have looked at the impacts of microfibers (natural and plastic) on human health in working conditions with very high concentrations of airborne fibres, 如织物制造和地毯铺设. In such jobs, a detrimental effect on lung health has been shown due to microfiber inhalation. What we are unsure of is whether there is an effect at normal levels, not just the very high concentrations encountered by people working in these industries.
目前最好的足彩app知道粒子(任何粒子, not just plastics) longer than 10µm are unlikely to get past our upper airways, 2以下粒子.5µm can get deep into our lungs, and particles less than 1µm can breach cell walls. 为了说明背景, 人类头发的平均宽度为75 μ m左右, 在目前最好的足彩app看到的最小范围内, 头发宽度的百分之一. 不幸的是，由于测量困难, most studies have only measured microplastics 10µm and above.
加强目前最好的足彩app的十大足彩平台, the University has purchased a specialist microscope that can reveal tiny pieces of plastic below 1 micrometre in size. This will enable us to identify microplastics at the size range which is most likely to impact our health, such as those with the ability to enter the bloodstream.
While there is currently no evidence for negative health impacts in our homes, we are working with the Portsmouth Hospitals NHS Trust to investigate the presence of microplastics in the lungs of chronic obstructive pulmonary disease (COPD) and asthma patients. Ultimately, this research may help alert patients of risk factors or triggers for their condition. 例如, avoiding places that have recently been carpeted where there may be a high number of fibres in the air, ensuring adequate ventilation when hoovering or when there is a lot of activity within carpeted areas.