Government House, "Kham" asks the public to be confident in the safety of tap water. The Metropolitan Waterworks Authority (MWA) revealed that the tap water production process uses layers of anthracite and sand filters that can capture small particles. The chances of tap water being contaminated with microbes are very low, including no protozoan contamination. Mr. Karom Polpornklang, Deputy Government Spokesperson, revealed that regarding the forwarding of messages about the discovery of dangerous contaminants in tap water, the Metropolitan Waterworks Authority, Ministry of Interior, has investigated and explained that the MWA monitors the quality of tap water from water pipes that distribute water to users' homes covering all service areas. There is a plan and goal to inspect tap water quality according to the World Health Organization's recommended values, covering physical, chemical, bacterial, toxic substances that are harmful to health, such as heavy metals, agricultural toxins, carcinogens (trihalomet hanes), radioactive substances, and various pathogens, including bacteria, protozoa, and viruses, totaling more than 100 items, by experienced scientists at ISO/IEC 17025 certified laboratories. Mr. Karam continued that in addition, external laboratories have been coordinated to verify the quality of tap water to ensure that tap water delivered to users' homes is clean and safe at all times. There is also a water quality integration center that monitors tap water quality through automatic real-time tap water quality measurement stations installed around the water distribution area, along with a downstream chlorine dispensing system installed at the water pumping station to control tap water to have an appropriate amount of free chlorine remaining. For other contaminants, the MWA has provided clarifications according to the list of inquiries as follows: PFOS (Perfluorooctanesulfonic acid) and PFOA (Perfluorooctanoic acid), which are chemicals in the PFAS (per- and polyfluoroalkyl substances) family that are synthesized by humans for industrial use, have the properties of reducing surface tension and preventing water and fat from adhering. Therefore, they are often used in coatings for household products, foams, pan coatings, protective clothing, shampoos, and firefighting foams. However, the European Union has issued regulations prohibiting the use of PFOS in products, and Thailand has announced that this group of substances is a Class 4 hazardous substance, which means that it is prohibited, but can only be used in the metal plating industry, which requires permission and reporting of use and waste management. Most entrepreneurs in Thailand have therefore stopped using this group of substances since 2009. According to statistics from the Department of Industrial Works, less than 300 kilograms of this group of substances are imported per year. Therefore, PFOS has a very low chance of contaminating water sources. As for various antibiotics, they contaminate in nature in very small quantities. Most of them do not have a direct effect on the human body. Moreover, the raw water sources used in the production of water by the MWA are not closed sources. They are sources of water that circulate all the time, so there is no accumulation of antibiotics. In other countries and in Thailand, standards or control criteria for these groups of substances have not been established, and there are no laboratories in the country that analyze antibiotic substances in water. Microplastics are plastic particles smaller than 5 millimeters (5,000 microns). They are often generated from the breakdown or break down of various plastics used in households and industries, such as personal care products containing microbeads, scrub beads in cosmetics and toothpaste. They are mostly spherical, oval, linear or sometimes irregular in shape. However, there is no standardized method of analysis for microplastics, no control criteria have been established, and there is a lack of sufficient research on their impact on humans. 'MWA has conducted resea rch in collaboration with the Faculty of Engineering and Industrial Technology and the Faculty of Science, Silpakorn University, to study the size, quantity, and types of microplastics throughout the tap water production process. For tap water from the Metropolitan Waterworks Authority, it was found that the filtration process in the tap water production process of MWA has a layer of anthracite and filter sand that can capture small particles. Therefore, the chance that tap water will be contaminated with microplastics is very low. Cryptosporidium, Giardia, and Cyclospora are protozoa that cause diseases in the digestive system, causing acute diarrhea. They can be found in natural water sources. Cyst or oocyst stages of protozoa can be detected. The infectious stage is resistant to unsuitable environmental conditions. Cryptosporidium oocysts are relatively round and approximately 4-6 microns in size. Giardia oocysts are oval-shaped and 8-14 microns in size. Cyclospora oocysts are 8-10 microns in size. MWA mon itors these pathogenic protozoa by sending raw water and tap water samples for analysis to the Department of Medical Sciences. The results of past analysis did not find any such protozoan contamination,' said Mr. Karam. Source: Thai News Agency