Relevant guidance documents on pollution prevention and control were issued years ago. Under the section regarding rigorous environmental risk prevention and control, targeted requirements were put forward for enterprises involving thallium, calling for investigation and remediation work for such facilities. Why is thallium emphasized in pollution prevention and control efforts?
Thallium presents high toxic risks, and adverse health impacts may occur even at low exposure levels. Thallium containing compounds have long been included in the list of priority restricted hazardous substances, and represent one of the key pollutants to be managed in wastewater treatment. Some may suggest simply phasing out thallium usage to avoid pollution. However, thallium has practical application value and is widely used in aerospace, electronics, healthcare, communications, national defense and other key sectors. Complete elimination of thallium application is not feasible, hence proper treatment measures are required to mitigate hazards linked to thallium.
Thallium is sparsely distributed in nature and mostly associated with sulfide minerals. A certain content of thallium can be found in many sulfide ore deposits. Industries including chemical processing, waste resource recycling, sulfuric acid production, battery manufacturing, and non ferrous metal mining, beneficiation and rolling may generate thallium containing effluent, which requires proper handling.
Water bodies are fluid. Thallium containing pollutants discharged into water can spread rapidly. Even limited volumes of thallium bearing waste may diffuse through water systems, posing potential risks to drinking water safety. It is critical to treat thallium in wastewater. Online Thallium in Water Analyzers can perform real time monitoring to help prevent thallium related water contamination.
Representative Thallium Related Incidents
- In 2016, improper wastewater discharge containing thallium by an enterprise in Jiangxi led to operational suspension of local water plants and temporary water supply cuts in some areas, implemented to secure drinkingwater safety.
- In 2017, an enterprise in Shaanxi discharged effluent with elevated thallium content, resulting in notable thallium exceedance within a local water section.
- In 2020, abnormal thallium concentrations were detected in the Hengyang section of the main Xiangjiang River, with thallium levels exceeding relevant standards in drinking‑water sources.
To sum up, enterprises handling thallium related materials shall complete thallium testing before wastewater discharge. Real time online water quality monitoring helps track thallium parameters in effluent and protects water sources against thallium contamination. It is also important to strengthen supervision and early warning capabilities for thallium risks and carry out thorough surveys of drinking water source areas.
Thallium is not the only hazardous substance present in wastewater. To guarantee safe drinking water supplies, multiple harmful parameters in wastewater shall be tested. Discharge is permitted only after all relevant indicators meet compliance requirements.
