After returning home from his job at a car battery recycling plant in northern Mexico one night in 2019, Azael Mateo González Ramírez said he felt dizzy, his bones ached and his throat was scratchy. Then came stomach pain followed by bouts of diarrhea, he said.
The plant in Monterrey where he worked handles used car batteries, many from the United States, extracting lead as part of the process. González, 39, stacked the batteries, he said, near large containers of lead dust.
Medical tests, González said, showed high levels of lead in his body; Experts agree that no level of lead is safe and can cause neurological and gastrointestinal damage over time.
His supervisor at the facility, he said, insisted that he keep working.
The city of Monterrey, a three-hour drive from Texas, has become the largest source of used car batteries in the United States, with steady growth over the past decade in the shipment of used US batteries to Mexico, according to the United States Environmental Protection Agency (EPA).
The surge in US batteries comes as a report released Monday found significantly high levels of lead in many facilities, leaving workers vulnerable to a toxic metal that poses serious risks to human health.
Soil samples taken outside six battery recycling plants in Monterrey in 2022 revealed lead levels well above the legal limit in Mexico, according to the report by Occupational Knowledge International, a San Francisco-based nonprofit public health organization. Francisco, and Casa Cem, a Mexican environmental group.
Although Mexico’s regulations stipulate that facilities must remove lead from contaminated soil and can be closed for violating environmental standards, Mexican government records show that few plants have been closed in recent years.
Mexico’s lax environmental laws and their even laxer enforcement encourage U.S. companies to dump used car batteries in the country, where labor is cheaper and unions are weaker, according to labor rights and occupational health experts. .
“Workers at these plants are being poisoned day after day, and often without even knowing it,” said Perry Gottesfeld, executive director of Occupational Knowledge International. “They don’t get the training, they don’t get the equipment, and they can’t operate in facilities that have proper ventilation.”
Over the past 10 years, the number of car batteries shipped to Mexico from the United States has grown by nearly 20%, according to EPA records included in the study for the two groups. In 2021, more than 75% of all used batteries in the United States were exported there, EPA records show.
At recycling plants, lead is extracted from batteries, ground up, melted down, and turned into ingots that are used to make new batteries.
The world’s largest auto battery maker, Milwaukee-based Clarios, bought two plants in Monterrey in 2019, and the report found lead levels in the soil outside its facilities that were well above the legal limit in Mexico. than 800 parts per million. (The samples in the report were tested and analyzed by an independent laboratory.)
At one Clarios plant, a soil sample showed lead levels of 15,000 parts per million, while at the other Clarios plant, a sample showed 3,800 parts per million lead.
Clarios closed its last US-based car battery recycling facility, in South Carolina, in 2021, following a series of EPA fines for violations related to air pollution, hazardous waste and transportation. unsuitable for lead batteries.
Shipping batteries to Mexico would save the company 25% in recycling costs, according to a Clarios filing with the Securities and Exchange Commission.
“There are certainly cost savings if you don’t have to worry about upgrading your facility to current US standards,” Gottesfeld said.
A Clarios spokesperson said the company’s facilities use “strict security protocols and we provide our employees with state-of-the-art security equipment.”
“We work with local health, safety and environmental authorities to ensure that our facilities are not only compliant, but set the benchmark for our industry,” said spokeswoman Ana Margarita Garza-Villarreal.
Although Mexico’s federal environmental agency has the power to shut down plants that violate environmental standards, agency documents show that officials temporarily closed parts of battery recycling plants just four times over air and soil contamination over the past four years. last 23 years.
Elizabeth Coronado was a nurse at a Monterrey plant owned by Grupo Gonher, where González had worked, and was responsible for monitoring the health of workers in areas with high lead exposure.
Of the roughly 300 workers whose blood samples they tested every three months, he said a third of them had 50 micrograms of lead per deciliter of blood in their system.
The average for battery recycling workers in the United States in 2022 was 9 micrograms, according to a battery trade group.
Lead experts in the United States say that workers whose lead level reaches 30 micrograms of lead per deciliter of blood should be removed from the source of the metal.
Grupo Gonher did not respond to a request for comment.
Although no amount of lead in the body is safe, levels like those found in workers at the Gonher plant can have serious consequences, said Dr. Michael Kosnett, an expert on workplace lead exposure and an adjunct professor. Associate at the Colorado School of Public Health.
“It should not be tolerated,” he said. “Among the most significant long-term adverse effects associated with adolescent blood lead or higher levels is a documented risk of death from heart disease.”
As for González, he said he had offered to curtain the containers containing lead dust. But his supervisor told him that it was not a priority.
González said he was fired from the plant in 2021 as part of what the company told him was a restructuring. In his five years at the plant, he had never missed a day of work, he said, and he believed he was fired, at least in part, because of concerns he repeatedly raised about lead exposure.
González, who now works renting out stereos for private events, said friends who work at the recycling plant say little has changed.
“There is a lot of poison in there,” he said.
