RETC in Mexico: what it is, which substances are reported and how to comply

The Pollutant Release and Transfer Register (RETC) is Mexico's public database that gathers information on the pollutant substances companies release to air, water, soil and subsoil, or transfer in their wastewater discharges and hazardous waste. It is coordinated by SEMARNAT and its purpose is transparency: to let the authority, industry and the public know which pollutants are released or transferred, where and in what quantities.

In short: the RETC is not a procedure you file, but the register built from the information companies declare each year through the Annual Operating Certificate (COA). If your establishment uses, produces or transfers any of the substances subject to reporting above their threshold, you must report it, and that data ends up integrated into the RETC.

What the RETC is

The RETC is a national inventory of pollutant releases and transfers. For each establishment, it gathers the quantity of certain substances it releases to the environment or transfers off-site, together with information on criteria-pollutant emissions from fixed sources. The idea is to have a periodic, comparable snapshot of the pollution pressure of the country's industrial activity.

It is important to place the RETC within the Mexican environmental system. It does not replace authorisations or the environmental impact assessment of projects; it is an information instrument: it collects operating data to understand and disseminate environmental performance, complementing other control and oversight mechanisms.

Legal basis: LGEEPA article 109 BIS

The RETC's foundation is article 109 BIS of the General Law on Ecological Equilibrium and Environmental Protection (LGEEPA). This article establishes the obligation of SEMARNAT, the states, Mexico City and the municipalities to build a register of pollutant releases and transfers to air, water, soil and subsoil, as well as of the materials and waste within their competence.

The reform that turned the RETC into a mandatory reporting instrument was published in the Official Gazette of the Federation in late 2001. The details (procedures for collecting, updating and disseminating information, and the responsibilities of establishments and the authority) are set by the RETC Regulation under the LGEEPA. And the specific substances to report, with their thresholds, are set by a Mexican Official Standard, within the broad catalogue of Mexican Official Standards.

The regulation itself, in article 9, specifies who counts as a federal-jurisdiction establishment subject to reporting: the fixed sources in the sectors of article 111 Bis of the LGEEPA (including hydrocarbon sector activities, which report through the Safety, Energy and Environment Agency, ASEA), hazardous waste generators, and anyone discharging wastewater into receiving bodies that are national waters. Falling into any one of the three categories is enough to be obligated.

Which substances are reported

Not just any substance is reported, but those included in the official list that also exceed a reporting threshold. That list and those thresholds are set by NOM-165-SEMARNAT-2013, published in the Official Gazette on 24 January 2014 and in force sixty days later. It contains 200 substances considered priorities because of their potential to harm the environment or health when released or transferred, each identified by its CAS number.

Each substance has two thresholds expressed in kilograms per year. The manufacture, processing and other uses (MPU) threshold applies when the substance, pure or contained in mixtures above 1% by weight according to the safety data sheet, is used or produced at the establishment. The release or transfer threshold applies when the substance, in any physical state, is released or transferred. Some examples from the list:

For a substance to require reporting, two conditions must be met at once:

• The substance must appear on the NOM-165-SEMARNAT-2013 list.
• Its release or transfer at the establishment must exceed the reporting threshold defined for it.

In addition to these substances, the register incorporates the criteria-pollutant emissions from fixed sources (such as particulates, nitrogen oxides, sulfur dioxide and carbon monoxide), which are also reported within the COA. The standard itself includes greenhouse gases and ozone-depleting substances, as article 18 of the regulation requires, and its appendices set out the criteria and procedure for adding or removing substances. Because the list and thresholds may be updated, the reference must always be the standard's text in force published in the Official Gazette.

How it is reported: through the COA

The RETC is fed mainly by the Annual Operating Certificate (COA). That is, companies do not report directly to the RETC as if it were a separate form: they declare their releases and transfers in the COA, and from that information SEMARNAT builds and updates the register.

The flow, in simplified form, is:

1. Throughout the year, the establishment records its consumption, processes, emissions, discharges and waste.
2. It identifies which listed substances exceed their reporting threshold.
3. It declares all that information in the COA, within the capture period (1 March to 30 June, referring to the previous year).
4. SEMARNAT processes the certificates and integrates the data into the RETC.

That is why understanding the COA's structure and calendar is essential to report correctly to the RETC: the detail of its sections, its electronic platform and its capture period determines which data ultimately reaches the register.

What happens after you submit the certificate

The RETC regulation sets a review procedure with specific deadlines. The authority has 20 working days to check that the certificate is properly completed and, if it is not, requires the establishment to complete, correct, clarify or confirm the information within a maximum of 15 working days. If the request is not answered, the certificate is deemed not filed, and a certificate that is not filed or contains false data opens the door to the penalties of the LGEEPA. If the establishment itself notices that the form is incomplete, it can remedy it within 15 working days of submission. The certificate is filed with the legal representative's electronic signature and the system issues an electronic acknowledgement.

As for how the data are obtained, releases and transfers regulated by a NOM must be measured with the methods, equipment and procedures that standard specifies. Those not regulated by a NOM, or whose measurement is exempt, may be estimated using emission factors, historical data, material balances, engineering calculations or mathematical models. Calculation records and measurements must be kept for five years from the filing of each certificate and be available to SEMARNAT on request.

Who is required to report

Establishments that are fixed sources and that release or transfer reportable substances above their thresholds are required to report. At the federal level, this takes shape through the federal-jurisdiction COA, which applies to federally regulated industrial sectors, large hazardous-waste generators and those who handle the listed substances.

The RETC also follows a logic of shared responsibility across levels of government: SEMARNAT builds the federal register, and the states and municipalities build theirs for the sources and waste within their competence. That is why it is key for each establishment to correctly identify its jurisdiction before reporting.

Public nature and penalties

An essential feature of the RETC is that it is public. Under article 25 of the regulation, the public information is the establishment's name or company name, its releases and transfers of substances and pollutants, and its geographic location, and it feeds into the National Environmental and Natural Resources Information System. SEMARNAT also publishes an Annual Report and, before the final version, releases a preliminary version at least 60 calendar days in advance so that establishments can check it matches what they reported; if there are discrepancies, they have 30 calendar days to request clarifications in writing. This public nature is precisely what gives the register meaning as a tool for environmental transparency and accountability.

On the compliance side, PROFEPA (or ASEA in the hydrocarbon sector) can request reports, data or documents and carry out inspection visits to verify what was reported and whether it was filed on time. Anyone receiving such a request has 15 working days to respond. Infringements are penalised under article 171 of the LGEEPA, which provides for fines of 30 to 50,000 days of minimum wage (a reference now calculated in UMA), temporary or definitive closure, administrative arrest of up to 36 hours and the suspension or revocation of licences and authorisations; in case of recidivism the fine can be tripled. Beyond the penalty, reporting with incorrect or incomplete data creates inconsistencies that can lead to information requests and greater scrutiny by the authority. For an overview of the Mexican environmental framework and how the RETC fits with other obligations, see our guide on environmental laws, NOMs and certifications in Mexico.

It is worth not confusing the RETC with greenhouse gas reporting to the National Emissions Registry, which we cover in the guide on RENE and the GHG Mexico Programme. The RETC focuses on local pollutants and hazardous substances; climate reporting measures the contribution to climate change and is expressed in CO2 equivalent. They are separate obligations, though both are channelled through the same certificate and share much of the source data.

Frequently asked questions

What is the RETC?

It is Mexico's Pollutant Release and Transfer Register, a public database coordinated by SEMARNAT that gathers establishments' releases and transfers of pollutant substances to air, water, soil and subsoil.

What is the RETC's legal basis?

Article 109 BIS of the LGEEPA, developed by the RETC Regulation under the LGEEPA, with substances and thresholds set by NOM-165-SEMARNAT-2013.

How is it reported to the RETC?

Through the Annual Operating Certificate (COA), in which companies declare their releases and transfers; from that information SEMARNAT builds and updates the register.

What happens if SEMARNAT asks me for information?

You have 15 working days from notification to complete, correct or clarify the certificate. If you do not, the certificate is deemed not filed and the establishment is exposed to the penalties of the LGEEPA.

Is the RETC public?

Yes. The register's information is disseminated publicly, including the establishment, its location and the quantities released or transferred, as a tool for environmental transparency.

If you want to identify which substances exceed their thresholds and reach the reporting window with a traceable record, you can centralise emissions, discharges and waste and calculate your establishment's carbon footprint with Manglai.