If you’ve recently gotten on the 22 Freeway from Studebaker Road or driven around the Port of Long Beach at night, you may have noticed a handful of streetlights that cast a purplish glow rather than the usual yellow or white light.

No, they weren’t put there by a rogue maintenance worker who was on acid or just really likes Prince.

In fact, the unexpected hue is a phenomenon that’s been seen across the country over the past few years, and it’s the result of a manufacturing problem with some LED bulbs commonly used in streetlights.

Since at least 2021, the defective lights have been spotted in Florida, North Carolina, Kentucky, Missouri and other locales, according to news stories.

The problem? As Cathy Lewandowski, a spokeswoman for lighting manufacturer Acuity Brands, explained in an email, “The referenced ‘blue light’ effect is due to a spectral shift caused by phosphor displacement seen years after initial installation.”

In case that wasn’t clear, the National Science Foundation website has this somewhat more accessible description of how LED lights work in a 2021 article on concerns about excessive exposure to blue light: “Inside the bulb, an LED chip converts electrical current into high-energy light, including invisible ultraviolet, violet or blue wavelengths. A cap that is placed on the chip contains multiple phosphors — solid luminescent compounds that convert high-energy light into lower-energy visible wavelengths.”

In other words, there was a problem with the phosphor coating on some of the LED bulbs that developed after they were installed.

When asked about the purple lights, Port of Long Beach Managing Director of Engineering Services Sean Gamette said in a statement, “We are experiencing a similar phenomenon in the Port of Long Beach. A small percentage of the LED streetlights (approximately 15%) are emitting a blue light. We are working to evaluate the cause, but believe it is a manufacturing defect and we are working with the manufacturer on an appropriate repair.”

That 15% equals about 70 of the port’s 460 LED light fixtures, mostly along Harbor Scenic Drive, Harbor Plaza and Pico Avenue, and they were installed between 2018 and 2020, according to port spokesman Lee Peterson.

While Port of Long Beach officials acknowledged the defective fixtures back in January, the handful of psychedelic-looking bulbs along the Studebaker/22 onramp were a harder nut to crack.

About two months ago, a Long Beach spokeswoman said the Studebaker lights didn’t belong to the city and suggested they might be Caltrans’ jurisdiction because of their proximity to the freeway.

A Caltrans spokesman subsequently said no, the agency wasn’t responsible for those light poles, which are behind a fence along the site where the Alamitos Energy Center sits—he suggested they might belong to AES, which owns Alamitos.

But alas, AES also would not claim the purple lights, instead providing an aerial photo and parcel map showing the poles are on Southern California Edison’s side of the property line.

At last, on Thursday, Edison spokeswoman Diane Castro put the mystery to rest.

The company had been unaware of the lighting defect, but after investigating, officials determined the light poles had been installed—maybe as long ago as the 1980s—as part of the perimeter lighting for an Edison substation, Castro said.

Now that it’s been brought to their attention, company officials are working on replacing the purple bulbs “as quickly as possible,” maybe before the end of the month, she said.

(Castro also noted that based on the shape and configuration of the faulty fixtures, they’re not from the same manufacturer that provided more than 300,000 LED lights Edison has put in across its service area; those remain the expected color.)

Acuity’s Lewandowski said only “a small percentage” of a particular type of company’s bulbs were affected, and other manufacturers had the same issue.

The purple light “is in no way harmful or unsafe” and the company is working with customers to address the problem, she said.

So if you spot a strange purple streetlight around Long Beach, hold an impromptu rave while you can, because it may not be there much longer.