Who released its first microplastics report, calling for measures to be taken: it's all in the water you drink!

According to the report, according to the information available so far, the microplastics in drinking water do not necessarily pose a threat to health. In spite of this, World Health Organization (WHO) still called on decision makers and the public to take measures to control and reduce the use of plastics as much as possible to improve the environment and promote human health.

According to World Health Organization (WHO) 's definition, microplastics usually refer to small plastic particles less than 5 mm in diameter. This report summarizes the latest information on the problem of microplastics in drinking water and analyzes the signs of microplastics in the water cycle, the potential health effects of exposure to microplastics, and the removal of microplastics during sewage and drinking water treatment.

The results show that plastic particles larger than 150um (0.015 cm) in diameter are "unlikely to be absorbed by the body" and that even smaller particles are difficult to be absorbed by the body. But microplastics with very small diameters, such as nanoplastics, may be more likely to enter the body.

The report cites studies on the effects of microplastics and nanoplastics on rodents, in which rodents have shown symptoms including liver inflammation. Nevertheless, the researchers insist that ordinary people are unlikely to be exposed to such large amounts of plastic pollutants in a short period of time.

Given that scientists still know little about this field, the report also suggests that further research is needed to more accurately assess microplastics and their potential effects on human health.

Dr. Maria Nera (Maria Neira), Director of World Health Organization (WHO) 's Department of Social Determinants of Public Health, Environment and Health (hereinafter referred to as "the Department of Public Health"), said: "the limited information we have shows that the microplastics in drinking water do not seem to pose a threat to human health at present. But we need more information to learn more about the health effects of microplastics. Because microplastics are everywhere, even in our drinking water. " She stressed the importance of studying microplastics in drinking water and curbing the "global rising trend in plastic pollution".

The report notes the presence of plastic pollutants in oceans, sewage, fresh water, food, air and drinking water (including bottled and tap water). The main sources of microplastic pollutants in the environment are surface runoff and sewage discharge, and the most common microplastic particles in drinking water are plastic bottle fragments.

Jennifer de Frans (Jennifer de France) of the Department of Public Health says that according to limited data, bottled water contains more plastic particles than tap water. The two most commonly detected polymers in drinking water are polyethylene terephthalate (PET) and polypropylene. PET is often used to produce bottled water, while polypropylene is often used to produce bottle caps. However, there are other polymers in drinking water, so further research is needed to determine the exact source of the polymer.

Bruce Gordon of the Department of Public Health says a more intuitive potential threat than microplastics is drinking water contaminated with human or animal waste. This threat can affect 2 billion people and claim 1 million lives each year. One of the ways for the government to address this threat is to establish a better sewage filtration system.

This has two major benefits: it can not only dispose of the excreta and chemicals in the sewage and improve human health, but also effectively remove most of the microplastics in the water.

It is reported that this can reduce the pollution of microplastics in sewage by about 90%. If the traditional drinking water treatment method is adopted, only particles less than one micron in diameter can be removed. A more effective cleaning method is three-stage treatment (Tertiary Treatment), that is, deep treatment.

In other words, sewage should not only be mechanically treated to remove impurities and biological treatment to remove harmful microorganisms, but also should be further removed by advanced treatment of fine suspended solids and other pollutants in the water.

However, World Health Organization (WHO) also stressed that there are still many people around the world who do not have access to adequate water resources and sound sewage treatment facilities, and that the treatment process of sewage and drinking water does not focus on the removal of microplastics. Therefore, governments, regulators, drinking water suppliers and communities need to work together to solve the problem of microplastics by constantly improving sewage treatment technology.

The water supply department should formulate plans to ensure water safety and take measures to ensure that a series of water supply links, including the water treatment process, can be carried out efficiently and smoothly, and optimize the water treatment process to remove particulate matter and harmful microorganisms from the water, this also helps to reduce the content of microplastics in the water.

The report also points out that there are many kinds of microplastics in water, and which treatment process is adopted to remove these microplastics mainly depends on the physical and chemical properties of the components of the microplastics. At present, the process of removing particulate matter in drinking water treatment can be divided into two types:

(1) Coagulation, flocculation, precipitation / flotation and filtration are used to purify water sources. This method is the most common and can effectively remove plastic particles less than one micron, but if you want to remove other smaller organic and inorganic matter, this method has little effect, and the effect of this method is easily affected by water pressure conditions.

(2) membrane process treatment (Membrane processes), including reverse osmosis membrane, nanofiltration membrane, microfiltration and ultrafiltration technology, in which nanofiltration membrane has the best effect and can filter out particles with diameters between 0.01 and 0.001 microns.

The report also warns that plastic waste generated during water treatment will not disappear voluntarily, but will be transferred to another stage and may even re-enter the treated water. The relevant departments should pay attention to it, optimize the technological process and properly dispose of these plastic wastes so as to prevent water resources from being polluted again.

In order to better understand the harm of microplastics to human health and provide a basis for control measures, World Health Organization (WHO) suggested to further explore the source and distribution of microplastics in fresh water and the whole water supply chain, as well as the effectiveness of different water treatment methods. at the same time, it is also necessary to develop a standardized method for detecting the content of microplastics in fresh water.

In order to reduce microplastic pollution, the report also proposes a series of measures, including the four major principles mentioned in the EU reduction Strategy (EU Plastics Strategy) issued in January 2018:

1. Improve the economic benefit of plastic recovery

two。 Curb the generation and stacking of plastic waste

3. Promote innovation and investment to develop environmentally friendly recycling and sustainable manufacturing solutions to reduce plastic waste

4. Strengthen international cooperation to reduce and eliminate plastic waste as much as possible.

Other measures proposed to reduce plastic pollution include plastic restraining orders, charges (such as charges or taxes on disposable plastic bags and bottles), producer accountability, and voluntary or compulsory use of non-plastic products. The report further emphasizes the importance of extensive cooperation, with government departments working not only with the publi