[Chinese Mainland] GB 4287—2026 Discharge Standard of Water Pollutants for the Textile Industry, effective September 1: Zebrafish Embryo Acute Toxicity Included for the First Time

Core Highlights: 2026年9月1日, the GB 4287—2026 "Discharge Standard of Water Pollutants for Textile Industry" issued by the Ministry of Ecology and Environment has been officially implemented. The new standard replaces GB 4287—2012 and three old standards for silk reeling, wool spinning, and hemp spinning, and for the first time adds a zebrafish embryo acute toxicity pollutant item, while optimizing indirect discharge control and unit product benchmark discharge volume. Textile printing and dyeing, a "major water user + major discharger," has entered a new round of upgrading cycles.

I. Standard Consolidation: Four Old Standards Unified into a Single Industry Discharge Standard

The textile industry covers multiple sub-sectors including printing and dyeing, silk reeling, wool spinning, and hemp spinning, which have long separately implemented the "Discharge Standard of Water Pollutants for Textile Dyeing and Finishing Industry" (GB 4287—2012) and three standards for "Silk Reeling," "Wool Spinning," and "Hemp Spinning." GB 4287—2026 for the first time integrates these four standards into a single industry discharge standard, unifying the scope of application, terminology definitions, and discharge limit system.

The integration is not a simple merger, but a redefinition of the standard's applicable objects: textile industry pollutant discharge units, production facilities, and textile industry centralized wastewater treatment facilities are all subject to this standard for water pollutant discharge management. This means that textile centralized treatment facilities that previously only referenced other industry standards as "park wastewater plants" now have a clear basis for compliance.

II. Key Changes: Toxicological Indicators, Indirect Discharge, Benchmark Discharge Volume

Compared with the 2012 version, the core changes of GB 4287—2026 are reflected in four dimensions:

• Zebrafish embryo acute toxicity included for the first time — The new standard adds the specific scope of application for pollutant items and introduces zebrafish embryo acute toxicity and discharge limits, marking the extension of textile wastewater control from "physicochemical indicators" to "ecotoxicological effects"
• Optimization of indirect discharge control — For scenarios where wastewater enters municipal wastewater plants or industrial centralized treatment facilities, indirect discharge control requirements have been optimized to reduce standard conflicts between enterprises and downstream treatment plants
• Refinement of benchmark discharge volume — The unit product benchmark discharge volume provisions are more complete, providing operable accounting basis for pollutant discharge units with different processes and product types
• Expansion of scope of application — Covering textile industry pollutant discharge units, production facilities, and textile industry centralized wastewater treatment facilities, achieving full-chain control of "generation—discharge—treatment"

The addition of zebrafish embryo acute toxicity is particularly noteworthy. This indicator can comprehensively reflect the combined toxicity of multiple pollutants in wastewater, and better characterizes the potential risk of wastewater to aquatic ecosystems than single chemical indicators. For printing and dyeing enterprises, this means not only controlling conventional indicators such as COD, ammonia nitrogen, and color, but also paying attention to composite toxicity sources such as dyes, auxiliaries, and heavy metals.

III. Why Is the Textile Industry Hit First?

The textile industry is one of China's major industrial wastewater dischargers. The printing and dyeing process involves large water consumption, complex water quality, high color, and abundant refractory organics, and the combination of different fibers, dyes, and auxiliaries leads to huge differences in wastewater composition. For a long time, textile wastewater treatment has faced the dilemma of "meeting standards is not difficult, stable compliance is difficult, and deep reuse is even more difficult."

With the implementation of GB 4287—2026, textile enterprises will face triple pressures:

• End-of-pipe upgrading — New toxicity indicators and stricter limits drive enterprises to upgrade wastewater treatment processes
• Process water conservation — Refined unit product benchmark discharge volume forces enterprises to reduce water intake per unit product
• Reuse expansion — Under the dual pressure of water resource constraints and total discharge control, Reclaimed Water Reuse will move from "optional" to "necessary"

For textile park centralized wastewater treatment facilities, the integration of standards makes responsibility boundaries clearer, but it also means they must assume more systematic management responsibilities for influent water quality, treatment processes, and effluent toxicity.

IV. Selection of Technical Routes for Upgrading and Retrofitting

Facing zebrafish embryo acute toxicity indicators and stricter discharge control, the technical routes for textile wastewater treatment are undergoing significant changes:

First, enhanced pretreatment. Conduct segregated collection of printing and dyeing wastewater by quality and category, and adopt differentiated pretreatment schemes for wastewater from different processes such as desizing, scouring, bleaching, dyeing, and printing, to reduce the toxic load entering the comprehensive treatment system.

Second, biochemical process upgrading. Traditional Activated Sludge processes are difficult to stably remove refractory organics, and the application proportion of combined processes such as Anaerobic Hydrolysis—A/O—MBR and Catalytic Ozonation—BAF will increase.

Third, coupling of advanced treatment and reuse. Membrane technologies such as Ultrafiltration, Reverse Osmosis, and Nanofiltration, as well as Advanced Oxidation processes, not only serve compliant discharge but are also directly linked to Reclaimed Water preparation. For textile enterprises with large water consumption, integrated "treatment + reuse" will become the key to cost reduction and efficiency improvement.

The implementation of GB 4287—2026 is both a new starting point for environmental compliance in the textile industry and a new window of opportunity for industrial water treatment and reuse technology suppliers. Companies capable of delivering "compliance discharge" and "water resource reuse" as a packaged solution will take the initiative in this round of upgrading and retrofitting.

About TIANYI TECH

Hong Kong TIANYI Technology Limited (TIANYI LIMITED) focuses on industrial water treatment and water resource reuse. Centered on three core products — Industrial Wastewater Treatment AI Agent, Industrial Water Reuse Optimization System, and Industrial Water System Digital Twin — the company provides enterprises with full-chain services from water quality diagnosis and process optimization to intelligent operations, helping customers increase water reuse rates and reduce operating costs.

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