Dozens of Amazon's own products have been reported as dangerous -- melting, exploding or even bursting into flames. Many are still on the market

(CNN) When firefighters arrived at Austin Parra's home on January 12, 2017, they could see smoke and the charred remnants of an office chair outside.

Parra, then 20, had been transported to the hospital. His mother explained to firefighters that her son's chair caught on fire while he was sleeping, and he was burned as he carried the flaming chair outside.

Anthony Dignoti, the Wethersfield, Connecticut, fire marshal in charge of investigating the incident, could see that the door and door frame were damaged by the fire as well. He noticed bowls strewn about, which he wrote in his official report had been filled with water in an attempt to extinguish the fire.

But most interesting to Dignoti was a white USB cord. Part of the cord was hanging off the chair and still intact, but the other side was stuck to the seat and had melted into a bare wire, he said in his report and an interview with CNN.

Dignoti ultimately concluded that the fire originated with the cord Parra was using to charge his cellphone. His report stated the cord experienced a short circuit, and while it was unclear why this happened, "the heat produced by the cord ignited the upholstery for the office chair."

The cord had been branded with the name of the world's largest online retailer: Amazon.

It was sold by one of Amazon's popular private label lines, AmazonBasics, which offers budget-friendly products including consumer electronics, household appliances, home goods and office accessories.

Launched in 2009, AmazonBasics has grown to offer more than 5,000 products, according to the retailer. Its mission: identifying everyday items that Amazon can create at a similar or higher quality and lower price point when compared to existing name brands -- a strategy also employed by companies such as Costco and Target.

A growing number of AmazonBasics products, which the company promotes heavily on its site, have become bestsellers since the line's inception, and many have ratings above four stars, according to Marketplace Pulse research. In recent months, the online retailer's sales have been soaring as millions of Americans have been staying at home -- and in many cases working remotely -- during the ongoing pandemic.

But consumers have raised serious safety concerns about AmazonBasics items in complaints to government regulators and in reviews posted on Amazon's own website. Since 2016, at least 1,500 reviews, covering more than 70 items, have described products exploding, catching on fire, smoking, melting, causing electrical malfunctions or otherwise posing risks, according to an analysis of AmazonBasics electronics and appliances listed on its website.

The reviews identified represent a small fraction of the overall purchases of the products, and fires caused by consumer electronics are not unique to Amazon branded items. User error can also be a factor, as can faulty or aging wiring within a home or a defective device being used in conjunction with the product.

But when well-made and used properly by consumers, electronics like those sold under the AmazonBasics name should rarely pose dangers, said electrical engineers interviewed by CNN.

Within the more than 1,500 reviews, many consumers explicitly called out items as potentially dangerous -- using terms such as "hazard" or "fire" or saying the product should be recalled. Around 30 items with three or more reviews like this remain for sale on Amazon.com today. At least 11 other products that fit this criteria were no longer for sale at the time of publication. Some became unavailable after CNN began its reporting, and at least four product pages were removed from the retailer's site entirely -- leaving behind dead URLs known by employees as "dog pages." Amazon confirmed that at least eight of these products had been under investigation, but said the company determined they all met its safety standards.

Customers have written in their reviews and said in interviews that they trusted that AmazonBasics purchases would be safe and well made since they were branded with Amazon's name and frequently touted as "Amazon's Choice." But even as complaints have mounted, the company has provided little or no information to consumers or the public about how it is handling allegations that some of its merchandise is unsafe.

Amazon shoppers have recounted frightening malfunctions and close calls in vivid detail: A surge protector turned into a "blowtorch," one father recalled -- saying that flames shot out of the device, which was near his baby's nursery. Phone chargers were said to have burned peoples' hands and legs, and exploding batteries allegedly sprayed chemicals in someone's face. A USB cord burst into flames in a parked car while a toddler was inside, according to one parent. A charger in another car was reported as starting an electrical fire on the freeway, allegedly burning the driver and a jacket. Paper shredders turned on by themselves, according to multiple consumers, and one reportedly blew up in a "fireball," burning someone's arm and singeing the hair off. And a microwave suddenly caught on fire when an 8-year-old went to heat up her macaroni and cheese cup as she had done "a zillion times," a mother claimed, saying she had to take the appliance outside and spray it with a hose. Each of these purchases were "verified," meaning Amazon confirmed that the customer who wrote the review actually purchased the product on the site and didn't receive a "deep discount," according to its website. Several were accompanied by photos of the burned items.

While the best way to determine why something malfunctioned is to physically test it and take it apart, many customers said they immediately threw out the defective devices or sent them back to Amazon at the company's request.

CNN obtained two damaged AmazonBasics products from customers: a microwave that a customer said caught fire and a USB cord a user said overheated and melted. These were tested by researchers at the failure analysis lab at the University of Maryland's Center for Advanced Life Cycle Engineering (CALCE) at CNN's request.

The USB cord was too burned for researchers to determine what had gone wrong. The microwave testing found that the design of the panel covering the heating device inside the microwave could result in the machine catching on fire, and determined that the way the panel was secured could allow debris such as food or grease to collect behind it and possibly ignite. As soon as the researchers turned it on, the microwave began sparking and smoking, causing it to react as if its user put foil or other metal inside. The testing was cut short when the lab was closed due to Covid-19.

"There's a risk in using this machine for sure, and it's a safety risk because this clearly heated up to the extent a fire could occur," said engineering professor Michael Pecht, who is the founder of CALCE and has previously assisted in government safety investigations. "This is more than a reliability problem, this is a potential safety problem."

Amazon did not comment on whether any improvements had been made to the microwave, but said it is confident the microwave is safe to use and that it continues to "meet or exceed" all of the applicable certification requirements.

The retailer said "safety is a top priority" at the company and that it takes a number of steps to ensure all AmazonBasics products are safe and high quality, such as selecting experienced manufacturers, monitoring customer feedback and testing items to ensure they pass safety and compliance standards both before and after they are available. It also said AmazonBasics offers thousands of products which combined have more than 1 million reviews, and that concerns are thoroughly investigated and that the company acts accordingly.

"The outcome of the investigation varies on a case by case basis and may include removing the product from the store, adjusting the design of the product, notifying customers to stop using the product, or other appropriate action," a company spokesperson said in a statement. "We want customers to shop with confidence and if ever a customer has a concern, they can contact customer service and we will investigate."

Amazon said there are a number of reasons an item may no longer be available, but that customers will be notified if a critical safety issue is identified. When asked how frequently the company has done this, Amazon said it had notified customers about an AmazonBasics product less than five times. It did not specify whether it did this for any of the items reviewed by CNN.

'It's a red flag'

Amazon has already been under intense scrutiny for allowing third party sellers with allegedly dangerous offerings to do business on the site, and multiple court rulings have found that the retailer can be held liable for defective items sold in its third party marketplace.

CNN's analysis focused on products sold with Amazon's own name on them -- a growing part of the retailer's business.

The reviews come from people living all over the United States and span five years, but they often call attention to the very same problems:

The same panel within a microwave catching fire, USB cords melting or burning despite no visible wear and tear or overuse, and paint on outdoor patio heaters lighting on fire. Consumers alleged items malfunctioned the first time they plugged them in. Others said electronics were not in use when they began malfunctioning.

In general, one or two reports of problems could be more easily chalked up to user error or other external factors, multiple electrical engineers said. But as the number of reports about the same kinds of failures increases about the same item, so does the likelihood that there is a defect in the design or manufacturing.

"That would certainly lead to more suspicion that the product is at fault," said Mark Horenstein, a professor at Boston University's College of Engineering. "It's a red flag."

Amazon said customer reviews are only one indication of a potential issue, saying it looks at a number of other factors such as sales history, returns and customer service contacts when assessing potential problems. "Using customer reviews alone to conclude a product is unsafe or imply there's a widespread issue is misleading," the company said in a statement.

Former Amazon employees said that even a few reviews mentioning words like "fire" and "hazard" should automatically prompt the retailer to take action. Amazon said reviews are monitored and can trigger safety investigations, but it declined to provide details about the specific threshold needed for this to happen. The company said products may be temporarily removed during such inquiries and that in order to keep selling something, it must be confirmed to be safe. It also said that if an investigation uncovers a "potential, non-isolated safety issue," it takes appropriate measures to notify the government and "safely recall the product."

Businesses are required by law to immediately report "potentially hazardous" items to the federal Consumer Product Safety Commission (CPSC) so the agency can determine whether an official recall is necessary. Companies can also initiate voluntary recalls in cooperation with the CPSC.

Concerns similar to those detailed in Amazon reviews have been relayed to the CPSC in at least 10 reports that specifically mention an AmazonBasics product. The complaints cover at least eight different items and date back to 2012.

In the United States, Amazon publicly recalled two AmazonBasics items in 2018 and 2019, after the company received 53 reports in the US about power banks overheating and 25 about versions of a space heater overheating, burning or sparking. It said it proactively notified the CPSC of the results of the company's own investigation and its intent to recall the items.

Beyond these two official recalls, the company has never publicly acknowledged that AmazonBasics products have any safety issues.

The CPSC said it was prohibited by law from discussing any item that had not been recalled and that in general, the agency determines if a recall is necessary based on a number of factors, including "the nature of the defect, the level of hazard associated with the issue, and the pattern of similar problems (seen)."

Customers reported being shocked or burned in at least 100 reviews on Amazon's website. Parra from the Connecticut apartment fire said in a lawsuit that he suffered second-degree burns and injuries to his throat from smoke inhalation. Dignoti's report shows Parra spent around a day in the hospital. Parra sued Amazon in 2019, and the case settled. He and his attorney did not respond to interview requests.

CNN used the information provided by the fire department to determine that the type of cord Parra purchased had been removed from Amazon's website. While it is unclear when the cord was pulled, a version of the page captured by the Wayback Machine, an internet archive, shows the product had an average rating of 4.1 out of 5 stars. It shows the cord was still available for purchase until at least June 2017, and that there were warnings from other customers at least a year before Parra's January 2017 fire.

"End of the cable melted and started smoking. Glad we caught it before a fire," one verified purchaser wrote in June 2016.

"DO NOT BUY! FIRE HAZARD!" another customer with a verified purchase of the cord wrote in May 2016, attaching 10 photos of the melted and warped cord -- saying it ruined an expensive iPhone and that he considered himself lucky that a fire hadn't ignited. "These should be taken off the market immediately!!!"

While fires caused by USB cords are uncommon, they are possible, according to electrical engineers who said a range of factors could be at play in situations like this -- from problems with whatever device the cord is plugged into to defects within the cord itself.

An industry non-profit, the USB Implementers Forum Inc, said it does not believe user error is a significant cause of overheating USB cables. A cable that is substandard, whether because of a design or manufacturing defect, can be dangerous and lead to electric shock, overheating, sparks or fire, it said. The group has certified a number of AmazonBasics cables as meeting their standards, though it focuses on the functionality of the cables and making sure their specifications are in compliance -- emphasizing that it is "not a replacement for industry best practices or any applicable local, state or government statutes, rules or regulations pertaining to safety."

The group also said it conducted an internal review of several cables CNN brought to its attention and found them to be compliant. It does not certify proprietary lightning USB cords used for Apple devices, however, such as Parra's cord. Apple said it allows manufacturers to use its lightning connectors in their products if those items are tested and confirmed to meet high quality standards, and that the company expects manufacturers to meet any applicable safety standards.

Amazon meanwhile said it investigated the safety claims about the kind of cord used by Parra and determined it met the company's standards. "If we determine that a product is unsafe, we remove it from our stores and take all necessary actions, which may include contacting regulators and customers," it said, specifically in response to questions about the cord used by Parra, which was removed from the site.

The retailer did introduce a new version of the product, however, saying it made updates to improve the customer experience.

Losing trust

Matt Citro purchased his AmazonBasics surge protector to protect his family from a fire. Instead, he said that in January 2018, the surge protector itself caught fire. A single phone charger was plugged into the device, but was not being used at the time.

Sitting on the couch as his 9-month-old son slept in his nursery nearby, Citro said he noticed flames coming out of the surge protector -- turning it into what resembled a "blowtorch." He told CNN that he quickly pulled the flaming device from the wall. He wasn't injured but said he was left with more than $1,000 of damage after the surge protector burned a hole in the wall outlet and seared part of his wall.

He had never experienced any electrical issues in his home before this, he said, and was convinced the AmazonBasics surge protector was to blame.

"DO NOT BUY THIS PRODUCT!!!...If I wasn't home my entire house would have burnt down from this cheap product," Citro wrote in a review. "I'm extremely disappointed in Amazon. We put a lot of faith in their products and to have (one) almost burn down my home does not make me trust them. This product has amazons name on it!"

Citro said he immediately contacted Amazon and told the company what happened. At first, he said he was offered a replacement or a refund. Not satisfied, he continued to call customer service.

He said he finally got through to someone who connected him with an insurance company, and he was ultimately paid $1,469, according to a settlement document reviewed by CNN in which Amazon denies any liability.

Amazon continued to sell the surge protector for nearly two years after Citro posted his review, during which time more reviews about similar situations and other concerns piled up. More than 40 customers reported that the product was a fire hazard, had caused damage to their home or belongings or described other dangers.

These reviews represented around 1.7% of the roughly 2,600 US reviews posted about the $10.99 device as of late last year, before Amazon removed it from the site. Several included claims of flames and fires like Citro's. As a comparison, a similar product made by a major consumer electronics company and also sold on Amazon's site had six reviews about possible safety concerns earlier this year, representing .07% of its more than 8,000 reviews. And none of the six mentioned actual fires. Amazon said its own analysis, which added global reviews about the AmazonBasics surge protector, found 1.1% involved claims of overheating, fire and other dangers.

One former AmazonBasics product manager, who asked to remain anonymous because she still works in the industry, said she was surprised to hear that such a high percentage of reviews raised safety issues about an AmazonBasics item. "Once you get 40, oh my gosh, no, that would not be acceptable in any shape, way or form," she said of the reviews found by CNN, adding that a ratio of around .05% would have been seen as more acceptable when she worked there. But she defended her former employer, saying this was just one product and that during her time with the company, she believed the retailer was even more vigilant than competitors in trying to react to safety concerns.

Weeks after CNN began reporting on the surge protector -- reaching out to customers and employees and ordering the same item as part of the investigation -- Amazon pulled it from its site in December despite its high average rating of 4.4 stars as of a month earlier. The company did not appear to provide any notification to customers, including to the reporters who purchased it. And it did not post any message on its site about why it was taken down.

Amazon declined to comment on individual customers, and would not say why the page was removed or whether Citro's surge protector was tested. It did say an updated version of the product had been released, but when asked for the link to the updated version, the company said "this product is currently unavailable."

Citro, who said he still shops at Amazon frequently, said he sent his burned surge protector back for testing as the company requested, but never heard anything about what its investigation found.

"I do wish this particular product was tested more thoroughly," he said. "A lot was on the line with my son's bedroom in the next room."

Just like Parra's phone cord, this specific kind of surge protector has not been officially recalled.

Behind the scenes

Three former Amazon employees said the vast majority of AmazonBasics electronics are made in Asia. The company's list of suppliers used for its various private label lines -- including AmazonBasics -- shows that only around 10% are in the United States and nearly half are located in China.

The retailer typically brings AmazonBasics items to market in two ways, explained the former product manager. It either goes straight to manufacturers that are able to meet its standards and works closely with them to create items for the AmazonBasics line. Or Amazon finds an existing product and works with a third-party company, which may use an outside manufacturer of its own, to brand the item with the AmazonBasics name.

She said both methods have been implemented for electronics, but that in this second scenario, Amazon typically has less insight into the manufacturing process and is less involved in quality and safety testing. Amazon disputed this, saying it verifies that products meet the same safety standards regardless of the business model. The company also said it most frequently works directly with manufacturers.

Related: Fake and dangerous kids products are turning up for sale on Amazon

Another former employee who was involved with AmazonBasics in its earlier years and asked to remain anonymous because of a confidentiality agreement, said employees on the AmazonBasics team would randomly order items to inspect and stay on top of reviews to make sure red flags were being caught. "We didn't have a lot of problems in my time but were much smaller than they are now so it was easy to keep things under control," the former employee said.

Former Amazon manager Rachel Greer, who left the company in 2015, said that when she worked in compliance at the company, she believed AmazonBasics products were closely monitored from conception to the years following their launch, saying there was extensive testing done. She said safety issues were rare, but when they occurred, they were caught quickly and addressed as soon as possible. "If someone complained on a review, we took it very seriously," she said.

This required staying on top of manufacturers and making sure corners weren't cut, she and the AmazonBasics product manager both said. In the case of USB cords, for example, Greer described how she made sure there was frequent testing of the cords to ensure that manufacturers hadn't begun to swap in thinner wiring which could be more likely to cause cords to overheat.

"When you're in charge of compliance for something that has the Amazon brand on it, I didn't think it should be something we're messing around with," Greer said. "When you're outsourcing production there's a lot of things that can go wrong."

When she left Amazon, she said she was growing concerned that a drive to increase sales would overshadow a focus on safety as the number of AmazonBasics offerings continued to rise. Prior to her departure, she would increasingly disagree with product managers, who she said pushed to get items into the pipeline faster and more cheaply. Performance evaluations reviewed by reporters backed up the idea that Greer had clashed with colleagues but also described her as "an evangelist for product safety," saying "she is passionate about keeping customers safe."

Greer now works as a consultant to third-party sellers, and said she wasn't surprised to hear that customers were complaining of alleged dangers. She said that when she worked for Amazon, she was never aware of anything close to the number or level of seriousness of the reviews identified by CNN, and questioned whether testing was still as rigorous as it had been in the past.

"If this had happened on a seller product, the second complaint of fire it would have been taken down," she said, while scanning through some of the more than 150 reviews about serious problems with a voice-activated AmazonBasics microwave — the same product tested by CALCE.

Greer said that if she was still at the company and had seen so many reports of fire about a single item, she likely would have reported the microwave to the CPSC and worked with the business teams to enact a voluntary recall by the company.

Since the microwave's release in the fall of 2018, its product page has been flooded with reports from consumers about problems including flames, smoke and sparks. These kinds of reviews made up roughly 5% of the AmazonBasics microwave's more than 3,000 reviews as of February, when CNN's final analysis was conducted. Another roughly 1,000 reviews have been posted since then, with fires being reported as recently as September. A microwave that has been reviewed less frequently but is the same size and wattage had only 10 reviews describing similar safety issues -- amounting to around .7% of its roughly 1,350 reviews on Amazon.

While the retailer did not provide unit sales, Amazon said that as the best-selling microwave on the site, it may have a higher number of sales and reviews, which could result in more mentioning possible concerns.

The company disputed Greer's comments, saying safety testing had not become any less rigorous and that it was not aware of any manufacturers using thinner cables "than they were directed to use." It said safety testing is handled by reputable third-party labs with global facilities, including in China and that her statements about the microwave were speculative since she was not part of the team that worked on this item and was not involved in the testing of the device. Amazon also said it proactively sends safety-related customer reports to the CPSC and noted the agency has not issued any consumer warnings about the AmazonBasics microwave.

Still for sale

Amazon declined to provide details about why certain products were investigated and removed from its site, while others with repeated complaints about the same hazards are still available to purchase today.

New mom Leeona Smail posted her review about an AmazonBasics battery charger late last year. When CNN reached her, she recounted how she and her husband were forced to evacuate their home in the middle of the night when they detected the unmistakable smell of something burning. They gathered their dogs, cats and 4-month-old baby by their front porch, called 911 and waited for help to arrive.

It wasn't until after the firefighters left that the Smails said they found what they believed awas the culprit: an AmazonBasics battery charger. They had used the device for several years to charge batteries. But this time, Smail said, after unplugging it from the wall and placing it in a box on their coffee table, it began to melt and smoke. When the fire chief returned the next day to check on them, she said, he was amazed to see the source of the smell.

A Vandergrift, Pennsylvania fire chief confirmed that his team was dispatched to investigate "a smoke odor and light haze" at the Smail home. He said they ultimately learned that a battery charger "overheated and melted," and said it was unclear whether it would have caused the house to catch fire if it hadn't been found.

Smail posted a photo of the burned device along with her review before throwing it away. Amazon eventually gave her a refund -- though she said she only received a partial one because the warranty window had passed.

At least 21 other reviews about the same battery charger, which had around 2,000 total reviews at the time of CNN's analysis, also said the device had overheated, melted or burned. Three described the same situation that Smail reported: the charger had not even been plugged in and had no batteries in it at the time.

The item was still for sale on Amazon at the time of publication.

The company said an investigation confirmed the product was safe, and that there were no broader design or safety concerns. But when asked whether it tested any of the actual chargers customers had flagged, and if so, what those tests had found, Amazon said it did not have "information to share."

What should we investigate next? Email us: watchdog@cnn.com.