[Chinese Mainland] GB 4287—2026 "Discharge Standard of Water Pollutants for the Textile Industry" Takes Effect on September 1: Four Standards Merged into One, Zebrafish Embryo Acute Toxicity Included in a National Standard for the First Time

2026 年 9 月 1 日, GB 4287—2026 "Water Pollutant Discharge Standard for Textile Industry" was officially implemented, replacing four standards at once: GB 4287—2012, GB 28936—2012, GB 28937—2012, and GB 28938—2012, merging the discharge rules separately managed for four sub-sectors—textile dyeing and finishing, silk reeling, wool spinning, and linen spinning—into a single yardstick. More notably, the standard for the first time lists "acute toxicity to zebrafish embryos" as a pollutant control item; new pollutant discharge enterprises shall comply from 2026 年 9 月 1 日, while existing printing and dyeing, silk, linen spinning, and wool spinning enterprises may defer compliance until 2028 年 1 月 1 日.

From "Governance by Sector" to "A Single Yardstick"

The revision logic of this standard is not simply tightening the limits, but rebuilding the management framework.

• Four in one, scope of application unified for the first time—The former "Water Pollutant Discharge Standard for Textile Dyeing and Finishing Industry" (GB 4287—2012) and its amendment were revised, while the "Water Pollutant Discharge Standard for Silk Reeling Industry" (GB 28936—2012), the "Water Pollutant Discharge Standard for Wool Spinning Industry" (GB 28937—2012), and the "Water Pollutant Discharge Standard for Linen Spinning Industry" (GB 28938—2012) were integrated and revised. The standard name was simultaneously adjusted from "Water Pollutant Discharge Standard for Textile Dyeing and Finishing Industry" to "Water Pollutant Discharge Standard for Textile Industry."
• Clear standard evolution—This standard was first issued in 1992 年, revised for the 1th time in 2012 年, and this is the 2th revision, fourteen years after the previous round.
• Covering the entire chain of water-related processes—From post-spinning finishing, silk reeling and cocoon cooking, wool fabric wet processing, to linen degumming, processes that were previously often outside strict regulation due to small scale and high dispersion are now all included in unified assessment.
• Centralized sewage treatment facilities separately included—The standard explicitly states that its scope of application includes centralized sewage treatment facilities for the textile industry, meaning that park-level centralized sewage treatment plants are no longer merely "downstream recipients of indirect discharge," but must assume discharge management responsibilities under this standard.

The four main lines given by the Ministry of Ecology and Environment in its interpretation are: law-based pollution control with differentiated management; science-based pollution control with green development; precision pollution control with risk prevention; and strengthening the synergy of pollution reduction and carbon reduction. Among these, "differentiated management" refers to determining control items and limits separately according to the production processes and pollution generation characteristics of various sub-sectors, and proposing differentiated requirements based on the different destinations of indirect sewage discharge.

Zebrafish Embryo Acute Toxicity Added to the Standard: From "Measuring Indicators" to "Measuring Toxicity"

The most technically significant change in this revision is the addition of acute toxicity to zebrafish embryos as a pollutant item and discharge limit.

• Why comprehensive toxicity—Textile dyeing and finishing wastewater has a complex composition. In addition to conventional COD, ammonia nitrogen, and color, it also contains auxiliaries, dye intermediates, and various residual organic substances. Relying solely on individual chemical indicators makes it difficult to reflect the combined effects of multiple co-existing pollutants; the comprehensive toxicity indicator fills precisely this gap.
• Clear applicable targets—This indicator is set for dyeing and finishing wastewater and centralized sewage treatment facilities for the textile industry, rather than a one-size-fits-all approach for the entire industry, reflecting a risk-oriented approach.
• Practical impact on enterprises—Once comprehensive toxicity exceeds the limit, it is still non-compliant even if all conventional indicators meet the standards. This forces enterprises to shift from "end-of-pipe compliance thinking" to "source toxicity control thinking": the selection of dyes and chemicals, substitution of auxiliaries, separation of clean and contaminated streams, and graded reuse all need to be re-examined.
• New requirements for water treatment operators—Traditional "coagulation sedimentation + hydrolysis acidification + aerobic" processes have limited capacity to reduce acute toxicity. Advanced oxidation (catalytic ozonation, Fenton), activated carbon/activated coke adsorption, membrane separation, and other advanced treatment units will shift from "optional" to "mandatory."

Indirect Discharge Redefined: Negotiated Limits Open Up Space for Park Governance

The standard "optimizes the control requirements for indirect discharge of water pollutants" and allows pollutant discharge units and operators of centralized industrial wastewater treatment facilities to negotiate and agree on discharge limits under certain conditions.

This seemingly technical clause actually has a significant impact. The significance of the consultation mechanism lies in the fact that if the centralized treatment facilities in the industrial park have stronger treatment capacity, upstream enterprises can relax certain conventional indicators within the agreed scope, thereby reducing redundant treatment costs and avoiding the redundant investment of "enterprises treating once, and the industrial park treating again." For the industrial park, this is a key step in translating systematic governance into the institutional framework; for operators, it means they can exchange process capability for influent flexibility and form differentiated competitive barriers.

At the same time, the standard refines and improves the provisions on benchmark water discharge per unit of product, extending the precision of control from "concentration" to "total amount and efficiency" — this is a more direct constraint for enterprises whose core competitiveness is water consumption per ton of fabric.

16 -month buffer period: a renovation window covering Keqiao, Shengze, and Nantong

Differentiated implementation deadlines are the most policy-flexible design of this standard.

• New pollutant discharge enterprises — must meet the new standard starting from 2026 年 9 月 1 日, with no buffer.
• Existing enterprises — existing printing and dyeing, silk, linen textile, and wool textile enterprises may postpone compliance until 2028 年 1 月 1 日, obtaining a renovation period of about 16 months. The renovation content includes upgrading the wastewater treatment system, modifying reclaimed water reuse pipelines, and installing online monitoring equipment.
• Concentrated impact on industrial belts — textile hubs such as Keqiao in Zhejiang, Shengze in Jiangsu, and Nantong gather large numbers of small and medium-sized printing and dyeing and finishing enterprises, many of which still use traditional high-water-consumption and high-emission processes, and the actual pressure of the buffer period is most concentrated there.
• Reuse rate targets have been raised — industry figures show that the water reuse rate in China's textile printing and dyeing industry is generally between 30%—40%, and under the impetus of the new standard, raising the reclaimed water reuse rate to above 60% will be a highly probable outcome. The need for advanced treatment of wastewater salinity and color will directly drive purchases of processes such as membrane separation and advanced oxidation.

The industry landscape is likely to move toward divergence: large textile groups have technical reserves and financial strength, and can complete renovations within the buffer period and use the opportunity to integrate regional production capacity; while small and medium-sized processing plants located outside industrial parks and relying on leased factory buildings may face practical obstacles such as insufficient land for pollution control facilities and complex environmental assessment procedures, and some less competitive enterprises may choose to exit.

Our judgment

TIANYI TECH Co., Ltd. has long provided wastewater treatment and reclaimed water reuse system solutions for municipal and industrial park clients. We believe that the real challenge of GB 4287—2026 is not the limit values themselves, but the new dimension of comprehensive toxicity: it switches the evaluation basis from "whether several chemical indicators are compliant" to "whether the effluent as a whole has biological toxicity," which is fundamental to the choice of process route. We recommend that relevant enterprises and industrial park operators prioritize three things: first, conduct a baseline acute toxicity test on zebrafish eggs for the existing effluent to understand the real risk, rather than waiting until 2028 年 for a last-minute rush; second, take "clean-dirty separation + quality-based reuse" as the main line of renovation, directly reusing low-concentration rinse water after quality-based treatment and separately advanced-treating high-concentration dyeing and finishing wastewater, which is more economical than full-volume mixed treatment; third, seek consultation limits at the industrial park level, using the capacity of centralized treatment facilities to exchange for renovation space for upstream enterprises and avoid duplicate investment. Whoever completes these three steps first will be able to turn compliance costs into competitive advantages.

About TIANYI TECH Co., Ltd. (TIANYI LIMITED): TIANYI TECH Co., Ltd. is deeply engaged in the field of wastewater treatment and reclaimed water reuse, and is committed to providing efficient, low-carbon, and sustainable water treatment solutions for municipal and industrial clients.