The beautiful sea is vast and innocent. It used to be the life of this blue planet. Today, marine micro-plastics erode our beautiful ocean like drugs. This article provides solutions for the prevention and control of marine microplastics.

As early as the 1970s, human research on marine microplastics has begun. Until 2004, British researchers published a paper on plastic debris in marine waters and sediments in Science, and for the first time proposed the concept of micro-plastics - plastic fragments and particles less than 5 mm in diameter, and called it " PM2.5 in the ocean."

The sources of micro-plastics mainly include sewage discharge, garbage dumping, equipment damage and material leakage in marine operations and ship transportation, human activities in coastal areas, and plastic pellets in natural environment and plastic fragments formed by physical plastics. Chips; particulate additives in daily necessities and polishing materials used in industry.

Microplastics are constantly being detected in water sediments and organisms around the world, especially in areas with densely populated human activities and rivers such as seaports and coastal zones.

Micro-plastics are small in size, large in specific surface area and strong in hydrophobicity. They are ideal carriers for many hydrophobic organic pollutants and heavy metals. Micro-plastics are easily eaten by plankton and fish, can stay in living organisms for a long time, and are transferred and enriched in food webs, posing a threat to ecological environment safety. On April 27, 2015, the United Nations Joint Expert Group on the Scientific Aspects of Marine Environmental Science issued, “Sources, Trends and Impacts of Micro-Plastics in the Ocean: A Global Assessment” equates the micro-plastics to marine life as large marine debris (eg fishing nets, Plastic bags, etc.). The micro-plastics entering the environment can be migrated under external forces such as wind, river, and ocean current due to their small particle size and low density. Microplastics are relatively stable in nature and can exist in the environment for a long time, but their surface physicochemical properties will change under the influence of sunlight, wind and waves.

Sampling methods for microplastics in environmental samples can generally be divided into three types: Selective sam pling, Bulk sam pling, and Volum e.reduced sam pling.

The direct selection method is a method of directly picking up microplastics from environmental samples by visual recognition. Especially plastic pellets with a particle size of 1 - 6 m m. It is easier to identify in the sample. The direct selection method is suitable for the collection of plastic pellets in sediments, especially in surface sediment samples.

The Time Series Sediment Capture is a time series sediment trap designed to collect sediment particles from oceans and lakes. The instrument can operate underwater for days to weeks or up to a year and a half.

The inner layer of the tapered funnel and the sampling bottle are specially made of natural polyethylene material to most effectively prevent the water sample from being contaminated. And each sample vial is sealed before and after each sample, and the external water cannot enter the bottle at all. The integrity of the sample is fully protected.

When the microplastic does not have a specific morphological structure and is mixed with other impurities. It is difficult to pick up microplastics by direct selection. A large sample method is required.

                                                                                                                        Sediment trap                                    Time series water collector

The large sample method refers to a sampling method that does not separate components in the field while retaining all samples. Commonly used in cases where microplastics are difficult to be recognized by the naked eye. For example, micro-plastics are covered by sediment particles; micro-plastics in environmental samples have low abundance and need to be pre-treated by concentration, enrichment, etc.; the particle size is too small to be observed by the naked eye.

The time series water collector automatically collects seawater in the deep sea or coastal waters based on a user-programmed sampling schedule to collect the original species. The water samples collected by the system are mainly used for the analysis of biological, dissolved nutrients, dissolved trace metals or dissolved organic carbon. With a 500ml sampling bag, the sampling capacity is stronger. Its main features are: multi-port valve device with patented technology, so that each sample does not interfere with each other; seawater does not need to pass through the water pump and is directly introduced into the sampling container; acid cleaning effectively eliminates the biological attachment problem of the inlet.

The concentrated sample method refers to a method of filtering, sieving, etc., a large number of samples at the sampling site immediately, and retaining the target components for further analysis. Among them, the large volume suction filtration system and the floating particle sampling system are the preferred instruments for the concentrated sample method.

The large volume suction system WTS-LV is a single, continuous extraction of large volumes of water, allowing water to pass through the "filter membrane or adsorption cartridge in the filter holder" to collect suspended and / or dissolved particulate matter in the water. Sampler.

WTS-LV can collect different types and sizes of biological samples and sediments by controlling the flow rate of water and the volume of water sample. The instrument share software will automatically record the sampling time, volume, pressure value and flow rate. When the WTS-LV is recycled, the user can easily download the data recorded during these samples.

The floating particle sampling system WTS 6-24-47FH is a set of instruments for on-site collection of suspended particulate matter in the aquatic environment. A dual multi-port valve allows the water to pass through 24 filters of 47 mm diameter in a time-series manner. The piston pump is located below the sample cell to protect the sample from contamination. The internal processor controls the multi-port valve and piston pump, allowing the computer to access multiple ports and piston pumps via serial communication (RS-232 port).

                                                                                              Floating particle sampling system                                                Large volume suction system