Jessica Alba works many, many hours.

It’s Kombucha Thursday at the Santa Monica headquarters of The Honest Company, which means that groups of young, stylish workers gather at communal tables in a converted toy factory to slurp fashionable fermented tea. Jessica Alba, Hollywood star and company cofounder, sits in the adjacent room. She’ll join her troops shortly, but for now she’s transfixed by a box of tampons that looks more like it holds an expensive candle than Kotex. “Dope!” she declares, approvingly.

“We’re using all-organic cotton and plant-based polymer and a bio-plastic applicator,” says the 34-year-old actress earnestly, contrasting that with the plastic content of drugstore tampons and their effect on hormones. Honest’s new feminine care line launches in July.

Alba can go similarly deep on almost all of The Honest Company’s 120 products, whether the ingredients in a new organic beeswax sunscreen or the clever insulation pocket hidden inside a chic $170 vegan-leather diaper bag. Yes, she has a pretty face — it seems as if every men’s magazine has named her the most beautiful woman in the world at some point — but it’s the details from which great fortunes stem.

Details and hard work. Alba laughs about how she once worked an 86-hour week as the star of James Cameron’s sci-fi TV series, Dark Angel — the series that launched her career. Now, she says, she spends those 86 hours at a vintage teal blue desk, overseeing marketing and brand development for a company that feeds a growing demand for safe, nontoxic products, particularly among young helicopter parents who treat children — and what goes near or inside them — like porcelain.

Safety sells. The Honest Company has experienced an absurd level of growth. In 2012, its first year selling products, it hit $10 million in revenue. By last year it was $150 million, and industry insiders are predicting over $250 million this year. The company is focused on growth over profits, boasting a current valuation to match: $1 billion.

That figure means Alba, who owns between 15% and 20% of the company, according to a source with knowledge of her investment, is sitting on a fortune of $200 million. She’s on her way to earning a spot on FORBES’ new ranking of America’s Richest Self-Made Women, just $50 million shy of Beyoncé and Judge Judy, who are tied at number 49. The only other two celebrities to make the inaugural list are Oprah and Madonna. The difference is that foursome made their money in their core field, media and music. Alba, at a young age, has done it in a completely unrelated industry. But ask Alba and she’ll tell you she and Honest are just getting started. “If we really want to make a difference in the world and people’s health, it’s billions and billions of dollars, not just one,” she says, surveying the open-plan company floor from a conference room above its wooden rafters.

Like most great ideas, The Honest Company was inspired by a need that wasn’t being filled. In 2008 Alba was newly engaged to Internet entrepreneur Cash Warren and pregnant with their first child. At a baby shower thrown by family and friends, she remembers her mother advising her to use baby detergent to prewash the piles of onesies she’d received as gifts. She used a mainstream brand and immediately broke out into ugly red welts, harkening back to a childhood spent in and out of emergency rooms and doctors’ offices.

“She was the most sensitive child,” remembers her mother, Cathy Alba, who wasn’t referring to her daughter’s emotional well-being. Raised on Air Force bases in such places as Biloxi, Miss. and Del Rio, Tex., Jessica’s bad allergies and chronic asthma made her predisposed to pneumonia, which she contracted about twice a year, often leading to two-week hospital stints.

Now covered in hives again — and wary of having her baby relive her own experience — Alba spent late nights on Google and Wikipedia researching the contents not just of the offending detergent but also of everything in her bathroom cabinet and under her kitchen sink. “I was like, ‘How can this be safe for babies if I’m having this type of reaction?’” she says. What she found terrified her: petrochemicals, formaldehydes and flame retardants in everyday household products from floor cleaners to mattresses. Some were listed on the ingredients label plain as day, with others disguised under the catchall of “fragrance,” which is entirely legal.

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Armed with Internet printouts and fear for the health of her unborn child, Alba first tried to shop around the problem but grew irritated trying to find natural and eco-friendly products that weren’t either extortionate or seemingly designed for yurt-dwelling vegan yogis. Or both. “I felt like my needs weren’t being met as a modern person,” she says. “I want beautiful design like everybody else. But it shouldn’t be premium-priced, and it should, of course, be safe.”