Even with the doors and windows closed, Venecia Yanez can't escape the head-splitting, metallic odors that permeate her Paramount home.
Yanez says the harsh fumes and smoke that waft in at all hours and the rusty residue she finds on her family's car must be coming from one of the metal-forging plants she can see from outside her apartment.
She and her neighbors on Vermont Avenue have long complained of headaches, nausea and burning throats. Yanez, 28, worries the emissions are harmful to her 14-month-old daughter.
"We breathe it every day and it just doesn't feel safe," she said.
Residents of this small, working-class city southeast of Los Angeles have for years watched regulators launch studies and promise stricter rules to protect homes and schools from toxic emissions from the array of metal-processing facilities operating in their midst. But they have seen little action.
Then, a few weeks ago, air quality monitoring detected high levels of a potent, cancer-causing metal in Paramount, forcing authorities to pay attention.
Now, what had been a slow-moving effort targeting one metal-forging plant has snowballed into a broad investigation, with teams of inspectors from several agencies fanning out to at least 20 facilities in the city's industrial spine, searching for the origin of the toxic hot spot.
The South Coast Air Quality Management District has not yet found the source of hexavalent chromium, a compound known to cause lung cancer, that was detected at more than 350 times normal levels starting in late October.
And it's not clear how long it could take.
Community groups and some civic leaders say the latest revelations in Paramount show that government in California has not done enough to address hot spots of pollution where industry operates near homes and schools.
California Assembly Speaker Anthony Rendon (D-Paramount) said: "I am concerned that our community has become the latest example of people being exposed to toxic chemicals because a company is breaking the law and regulators haven't been aggressive enough in enforcing that law." He urged the air district to "find the culprit and fix the problem — now."
The South Coast air district began looking into toxic emissions in Paramount in 2013, after community complaints of burning metallic odors. The investigation centered on one metal-processing operation, Carlton Forge Works.
The agency tested the air at a school and two other sites downwind from the facility, and in January 2014 it notified the public that it had detected elevated levels of hexavalent chromium and nickel, another toxic metal that can harm the lungs.
As Carlton Forge Works took steps to improve its pollution controls, nickel concentrations fell. But hexavalent chromium did not. By 2015, air district monitors showed that it was ticking upward. A Carlton spokeswoman suggested recently that the readings were coming from a source several blocks upwind.
In August, air district officials revealed the carcinogen had been detected in a residential area at five times normal levels. They held a public meeting and pledged to expand air-quality monitoring to areas upwind of Carlton Forge.
Within days of setting up more monitors in October, officials discovered a hexavalent chromium reading of 26 nanograms per cubic meter — one of the highest they could recall — in a predominantly industrial area near Madison Street and Minnesota Avenue.
Air regulators and public health officials say there is no immediate threat that would require residents to relocate. They do not yet have an estimate of potential cancer risk, which can increase over years and decades of exposure.
The carcinogen, also known as Chromium 6, is a familiar menace. It's the same compound that polluted the water of Hinkley, Calif., made famous in the 2000 film "Erin Brockovich." Over the years, air quality regulators have periodically discovered it at alarming levels near chrome-plating and metal-finishing shops.
But air district officials said their recent efforts to track down toxic emissions in Paramount — including the deployment of 10 air quality monitors — are unprecedented.
"I'd challenge any other agency to match the speed, the transparency that we're moving at now," Wayne Nastri, the air district's acting executive officer, said at a Nov. 9 public meeting.
Paramount recently provided the air district with a list of 88 metal-related businesses in the city, which the agency is comparing with its own records to identify any unpermitted operations.
So far, the air district has cited one small metal-fabricating plant near the hot spot for operating equipment without permits.
Pro Cast Industries General Manager Christopher Tovar disputed that the equipment cited at the business requires permits and alleged that nearby, "there are other, bigger companies operating for years without permits."
Air district officials said Tuesday that they had conducted source testing of emissions from two facilities near the hot spot, Anaplex Corp. and Aerocraft Heat Treating Co., Inc., and had sent them letters notifying them that they may be designated potentially "high risk level" facilities.
Anaplex released the most hexavalent chromium of the five facilities in Paramount that have reported such emissions since 2013, air district records show.
An Anaplex representative reached by phone declined to comment, citing the investigation by air quality regulators. An Aerocraft spokeswoman said it was "still uncertain" that the facility was contributing to the problem but that the facility was reviewing its processes, cooperating with the investigation and "will take necessary actions to resolve any issues."
Though the investigation is ongoing, air district officials believe it could ultimately lead to orders to stop operations, civil penalties or criminal charges.
Air quality officials said they have received about 350 complaints in Paramount since 2011, with more than 60% of them related to metal-processing operations.
Teacher Lisa Lappin has called in dozens of complaints to the air district, starting several years ago, out of concern for the health of the second-grade students she taught at Lincoln Elementary School at the time.
Yanez and others said they have also complained to city hall.
In recent public meetings, residents of the 80% Latino city have criticized environmental regulators and their majority-white city council, questioning why they have not cracked down on polluting industries.
A letter from the city council accused air district staff of blindsiding it by releasing "inflammatory" information to reporters, communicating in "jargon-heavy, scientific ways" and delivering a "highly technical" presentation to residents.
Paramount Mayor Daryl Hofmeyer suggested in remarks at a recent council meeting that the city had placed too much trust in air quality officials.
Hofmeyer owns a livestock feed business and other property near several metal-processing operations. According to financial disclosure statements, he also has reported receiving rental income from Press Forge, a large metal forging and manufacturing facility.
In response to an inquiry from The Times, Hofmeyer said in a statement Wednesday that the property he has leased to Press Forge since 2008 for parking, storage and cutting work "in no way presents an existing conflict of interest, either legal or perceived." He said he would recuse himself from matters before the council "that in any way could have a financial impact on Press Forge."
Residents have spoken critically of officials at public forums. Some attest to health problems, reading off names of friends and relatives who have died of cancer. Some have demanded an expansion of pollution monitoring to include schools and other neighborhoods in the city of 55,000, which air regulators say they are considering. Others are forming new activist groups, printing out stacks of fliers and encouraging neighbors to phone in complaints and demand a solution.
"We just want to get our air back to a safe level," said Laurie Guillen, a lifelong Paramount resident who was spurred to action by the recent disclosures.
One factor in Paramount's pollution woes is hard to fix: A legacy of poor land-use planning that put homes, schools and heavy industry too close together.
Much of the city developed in the postwar period on former dairy land. It incorporated in 1957 and is now home to an array of metal shops and factories. That includes chrome platers, metal-finishing operations and several forging facilities that manufacture components for the aerospace industry.
"There's no escaping it because industry intertwines our community," said Maria Anguiano, whose daughter struggles with asthma.
At its Dec. 13 meeting, the Paramount City Council is expected to consider a moratorium barring new metal businesses. Hofmeyer said he would recuse himself.
Paramount residents have also faulted air regulators for failing to impose stronger rules they promised years ago to control toxic emissions from metal-processing facilities that operate across the region. The proposed rules, which seek to reduce toxic emissions from grinding operations at two dozen metal-forging facilities — including five in Paramount — have been repeatedly delayed.
Joseph Lyou, an air district board member who heads the Coalition for Clean Air, said he has been asking staff to bring forward those rules for years and called it "terrible" that the agency has not acted to fix "a frustrating gap in the regulations."
Meanwhile on Vermont Avenue, Venecia Yanez watched her daughter crawl in the the grass on a recent afternoon and wondered if the fumes that continue to sully the air are also falling down and poisoning the ground.
Yanez has attended two public meetings, her infant daughter in tow, to voice her concerns and invite air quality officials to visit and test the air at her home.
She is waiting for them to knock on her door, tell her what they're breathing and do something about it.
"If it was their family members living here it would be different, perhaps," she said. "Perhaps you go nose-blind. I'm still trying to see if that happens."
"Paramount's a nice place to be," she said, "but it's unbreathable."
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