What Are the
Definition of Emerging Contaminants
From the point of view of improving the quality of ecological environment and environmental risk management, emerging contaminants refer to those toxic and harmful chemicals that have the characteristics of biotoxicity, environmental persistence and bioaccumulation, and have great risks to the ecological environment or human health after entering the environment, but have not been included in environmental management or the existing management measures are insufficient. At present, there are four major categories of emerging contaminants that are widely concerned at home and abroad: persistent organic pollutants, endocrine disruptors, antibiotics and microplastics.
Compared with the familiar conventional pollutants such as SO2, NOx and PM2.5, the public has a shallow understanding of emerging contaminants. In fact, emerging contaminants, like conventional pollutants, come from industrial production, daily life and agricultural activities. The national list of emerging contaminants has listed 14 emerging contaminants, including PFOS, PFOA, PFHxS, short-chain chlorinated paraffin, dichloromethane, chloroform, nonylphenol, antibiotics and obsolete chlordane.
Four Characteristics of Emerging Contaminants
1. The risks of most emerging contaminants are long-term hazards and hidden, and their short-term hazards are not obvious. Once their hazards are discovered, emerging contaminants may have entered the environment and even the human body through various channels.
2. Emerging Contaminants have high stability, are difficult to degrade in the environment and easy to accumulate in the ecosystem. They can accumulate in the environment and organisms for a long time, and migrate for a long distance with the media such as atmosphere, water and soil or spread along the food chain.
3. Most of the emerging contaminants have a variety of biological toxicity, such as organ toxicity, neurotoxicity, reproductive and developmental toxicity, immunotoxicity, endocrine interference effect, carcinogenicity, teratogenicity, etc., causing potential harm to the ecological environment and human health. Long-term abuse of antibiotics may lead to the pollution of resistance genes, and even lead to some diseases without medicine. Unqualified water bottles containing bisphenol A will threaten the health of fetuses and children.
4. Some emerging contaminants are newly synthesized by human, which have excellent product characteristics, and their substitutes and alternative technologies are not easy to develop. Some emerging contaminants are widely used by human, involving a wide range of industries and a long industrial chain. The content of emerging contaminants in the environment is low and scattered, so it is difficult to control the production, use and pollution. In addition, the research foundation of migration, transformation and natural purification of emerging contaminants is weak, which makes it difficult to control emerging contaminants.
Treatment of Emerging Contaminants
The state attaches great importance to the treatment of emerging contaminants, and in May 2022, it issued the Action Plan for the Treatment of Emerging Contaminants, which comprehensively deployed the treatment of emerging contaminants. To carry out the treatment of emerging contaminants, with the effective prevention of environmental and health risks of emerging contaminants as the core, the prevention and control idea of "Screening, Evaluation and Control", "Prohibition, Reduction and Treatment" is constructed, in which "Screening" and "Evaluation" are the methods and foundations, and "Control" is the purpose and means.
Screening: Screening the environmental risks of chemical substances.
Evaluation: Accurately screen out emerging contaminants that need to be key controlled.
Control: formulate environmental risk control measures for the whole process.
Prohibition: Prohibit and restrict the use of raw materials that can produce Emerging Contaminants from the source.
Reduction: Reduce the discharge of emerging contaminants in the production process of chemical products.
Treatment: Strengthen the terminal treatment of emerging contaminants in the environment.
Social Co-treatment
The treatment of emerging contaminants is related to everyone's health and safety, which requires the participation of the whole society. Industrial enterprises should prohibit the production and use of PFOS, PFOA, PFHxS and short-chain chlorinated paraffin, and restrict the use of dichloromethane and chloroform. Hospitals should study and promote the safety control of antibiotics discharged from medical wastewater. The public should reduce the use of plastic bags and plastic tableware, do a good job in sorting garbage and practice green life.