UN drinking water report calls for a crackdown on microplastic pollution

Tiny particles of plastic carrying ‘biofilms’ that could contain disease causing bacteria and which may already be entering our guts have contaminated drinking water supplies around the world, a landmark UN report has warned.

The World Health Organization (WHO) has compiled the most comprehensive review to date of the evidence of microplastics – tiny plastic particles measuring less than five millimetres (0.2 inches).

Microplastics have hit headlines over recent years, as they have been detected in marine water, wastewater, fresh water, food, air and drinking-water, both bottled and tap water.

Now, for the first time, WHO has examined the potential human health impacts of exposure to microplastics through drinking-water.

The study also outlines areas for future research that could shed light on the scale of the problem and what we can do about it.

That includes finding out where most microplastic pollution is, where it is coming from, how it may impact human health and what can be done to stop more of these particles from entering our drinking water. 

Some of the key findings include the revelation that larger microplastic particles, bigger than 150 micrometres, are likely to be passed out of our bodies without harm.

Smaller particles could potentially be absorbed into our organs, however.

It also suggests microplastics have the potential to both carry disease-causing bacteria and help bacteria become resistant to antibiotics.

Tiny particles of plastic carrying 'biofilms' that could contain disease causing bacteria and which may already be entering our guts have contaminated drinking water supplies around the world, a landmark UN report has warned. This graphic shows the biggest producers of plastic worldwide, as well as predicted growth for the future

Tiny particles of plastic carrying 'biofilms' that could contain disease causing bacteria and which may already be entering our guts have contaminated drinking water supplies around the world, a landmark UN report has warned. This graphic shows the biggest producers of plastic worldwide, as well as predicted growth for the future

Tiny particles of plastic carrying ‘biofilms’ that could contain disease causing bacteria and which may already be entering our guts have contaminated drinking water supplies around the world, a landmark UN report has warned. This graphic shows the biggest producers of plastic worldwide, as well as predicted growth for the future

TOP 5 RATED STUDIES THAT HAVE UNCOVERED MICROPLASTIC POLLUTION IN FRESH WATER
Water source   Results (particles per litre)   Authors  
Groundwater, Germany  0.0007  Mintenig et al, 2019 
Three Gorges Reservoir,China 4.7 Di and Wang, 2018
Dongting Lake, China 1.2 Wang et al, 2018
Hong Kong Lake, China 2.3 Wang et al, 2018
Rhine river, Europe 0.0056 Mani et al, 2015
Western Lake Superior,USA 0.00026 Hendrickson, Minor,and Schreiner, 2018

There has been very little research to date that has looked at the issue of microplastics in drinking water, the WHO report warns. 

The information within it was collected through literature reviews on all scientific studies carried out on the occurrence of microplastics in the water cycle.

It also gathered evidence on the potential health impacts from microplastic exposure and the removal of microplastics during wastewater and drinking-water treatment. 

WHO experts examined and rated the quality and relevance of all of the studies they found during this process. 

The report recommends that drinking-water suppliers and regulators prioritise removing disease-causing bacteria and harmful chemicals from the water supply, as that would also remove microplastics from drinking water. 

Ultimately, the best solution is to stop polluting the world with plastics, the report says.

Dr Andrew Mayes, from UEA’s School of Chemistry, developed a test that revealed microplastics in bottled water around the world.

The rapid screening method identifies microscopic plastic particles – as small as a few micrometres – in water and sediment samples.

The World Health Organisation has compiled the most comprehensive review to date of the evidence of microplastics - tiny plastic particles measuring less than five millimetres (pictured in this file photo)

The World Health Organisation has compiled the most comprehensive review to date of the evidence of microplastics - tiny plastic particles measuring less than five millimetres (pictured in this file photo)

The World Health Organisation has compiled the most comprehensive review to date of the evidence of microplastics – tiny plastic particles measuring less than five millimetres (pictured in this file photo)

Microplastics (pictured in this file photo) have hit headlines over recent years, as they have been detected in marine water, wastewater, fresh water, food, air and drinking-water, both bottled and tap water

Microplastics (pictured in this file photo) have hit headlines over recent years, as they have been detected in marine water, wastewater, fresh water, food, air and drinking-water, both bottled and tap water

Microplastics (pictured in this file photo) have hit headlines over recent years, as they have been detected in marine water, wastewater, fresh water, food, air and drinking-water, both bottled and tap water

Now, for the first time, WHO has examined the potential human health impacts of exposure to microplastics (pictured in this file photo) through drinking-water

Now, for the first time, WHO has examined the potential human health impacts of exposure to microplastics (pictured in this file photo) through drinking-water

Now, for the first time, WHO has examined the potential human health impacts of exposure to microplastics (pictured in this file photo) through drinking-water

The study also outlines areas for future research that could shed light on the scale of the problem and what we can do about it. That includes finding out where most microplastic pollution (pictured in this file photo) is, where it is coming from, how it may impact human health and what can be done to stop more of these particles from entering our drinking water

The study also outlines areas for future research that could shed light on the scale of the problem and what we can do about it. That includes finding out where most microplastic pollution (pictured in this file photo) is, where it is coming from, how it may impact human health and what can be done to stop more of these particles from entering our drinking water

The study also outlines areas for future research that could shed light on the scale of the problem and what we can do about it. That includes finding out where most microplastic pollution (pictured in this file photo) is, where it is coming from, how it may impact human health and what can be done to stop more of these particles from entering our drinking water

The method ‘sees’ microplastic particles, by staining them using fluorescent Nile Red dye. The dye adsorbs onto plastic surfaces, making them fluorescent when irradiated with blue light. These fluorescent particles can then be visualised and counted.

This research led to the report, which also calls for a reduction in plastic pollution to benefit the environment and reduce human exposure.

Commenting on the report, Dr Mayes, said: ‘As might be expected from a WHO-commissioned report, this is a pretty comprehensive synthesis of all the currently-available scientific evidence.

‘The report is well balanced and seeks to assess the risks in an overall context relative to other likely risk factors. By drawing together all the available and often disparate evidence, the working group has added considerable value to the literature through thoughtful and detailed analysis.

‘The key finding, that microplastics in drinking water pose a low risk to human health, based on current available evidence, will no doubt come as a relief to worried members of the public.  

‘Lack of rapid, cost effective and reliable methods for detecting and analyzing microplastics is a key bottleneck in much of the required research effort to understand the sources, distribution behaviour and fate of microplastics, both in environmental and medical contexts.

‘Hopefully, highlighting this issue in such a prominent way in the report will encourage the research community and funding agencies to address this gap in an urgent and concerted way.’ 

WHAT FURTHER RESEARCH IS NEEDED TO ASSESS THE SPREAD AND IMPACT OF MICROPLASTICS?

The World Health Organisation’s 2019 report ‘Microplastics in Drinking Water’ outlined numerous areas for future research that could shed light on how far spread the problem of microplastic pollution is, how it may impact human health and what can be done to stop these particles from entering our water supplies.

How widespread are microplastics?

The following research would clarify the occurrence of microplastics in drinking-water and freshwater sources:

  • More data are needed on the occurrence of microplastics in drinking-water to assess human exposure from drinking-water adequately. 
  • Studies on occurrence of microplastics must use quality-assured methods to determine numbers, shapes, sizes, and composition of the particles found. They should identify whether the microplastics are coming from the freshwater environment or from the abstraction, treatment, distribution or bottling of drinking-water. Initially, this research should focus on drinking-water thought to be most at risk of particulate contamination. 
  • Drinking-water studies would be usefully supplemented by better data on fresh water that enable the freshwater inputs to be quantified and the major sources identified. This may require the development of reliable methods to track origins and identify sources. 
  • A set of standard methods is needed for sampling and analysing microplastics in drinking-water and fresh water. 
  • There is a significant knowledge gap in the understanding of nanoplastics in the aquatic environment. A first step to address this gap is to develop standard methods for sampling and analysing nanoplastics. 

What are the health implications of microplastics?

Although water treatment can be effective in removing particles, there is limited data specific to microplastics. To support human health risk assessment and management options, the following data gaps related to water treatment need to be addressed: 

  • More research is needed to understand the fate of microplastics across different wastewater and drinking-water treatment processes (such as clarification processes and oxidation) under different operational circumstances, including optimal and sub-optimal operation and the influence of particle size, shape and chemical composition on removal efficacy. 
  • There is a need to better understand particle composition pre- and post-water treatment, including in distribution systems. The role of microplastic breakdown and abrasion in water treatment systems, as well as the microplastic contribution from the processes themselves should be considered. 
  • More knowledge is needed to understand the presence and removal of nanoplastic particles in water and wastewater treatment processes once standard methods for nanoplastics are available. 
  • There is a need to better understand the relationships between turbidity (and particle counts) and microplastic concentrations throughout the treatment processes. 
  • Research is needed to understand the significance of the potential return of microplastics to the environment from sludge and other treatment waste streams. 

To better understand microplastic-associated biofilms and their significance, the following research could be carried out:

  • Further studies could be conducted on the factors that influence the composition and potential specificity of microplastic-associated biofilms. 
  • Studies could also consider the factors influencing biofilm formation on plastic surfaces, including microplastics, and how these factors vary for different plastic materials, and what organisms more commonly bind to plastic surfaces in freshwater systems. 
  • Research could be carried out to better understand the capacity of microplastics to transport pathogenic bacteria longer distances downstream, the rate of degradation in freshwater systems and the relative abundance and transport capacity of microplastics compared with other particles.
  • Research could consider the risk of horizontal transfer of antimicrobial resistance genes in plastisphere microorganisms compared to other biofilms, such as those found in WWTPs. 

Can water treatment stop microplastics entering our water supplies?

Although water treatment can be effective in removing particles, there is limited data specific to microplastics. To support human health risk assessment and management options, the following data gaps related to water treatment need to be addressed: 

  • More research is needed to understand the fate of microplastics across different wastewater and drinking-water treatment processes (such as clarification processes and oxidation) under different operational circumstances, including optimal and sub-optimal operation and the influence of particle size, shape and chemical composition on removal efficacy. 
  • There is a need to better understand particle composition pre- and post-water treatment, including in distribution systems. The role of microplastic breakdown and abrasion in water treatment systems, as well as the microplastic contribution from the processes themselves should be considered.
  • More knowledge is needed to understand the presence and removal of nanoplastic particles in water and wastewater treatment processes once standard methods for nanoplastics are available. 
  • There is a need to better understand the relationships between turbidity (and particle counts) and microplastic concentrations throughout the treatment processes. 
  • Research is needed to understand the significance of the potential return of microplastics to the environment from sludge and other treatment waste streams.

Link hienalouca.com

(Просмотров всего: 9 Время, 1 визитов за день)

Leave a Reply

Your email address will not be published. Required fields are marked *