Police Captain Marc Reina said the make-up was “found to contain bacteria and human waste”.
He tweeted a picture of the counterfeit goods saying: “The best price is not always the best deal! #ProtectingOurCommunity.”
Detective Rick Ishitani told ABC7: “They came back positive with a high level of bacteria and animal faeces.
“Those faeces will just basically somehow get mixed into the product they’re manufacturing in their garage or in their bathroom – wherever they’re manufacturing this stuff.”
The detective warned customers the price is a good indicator of whether the product is fake.
He said: “If you’re getting something that’s 50 percent off, 75 percent off – it tells you that it’s bad.”
Six people have been related in connection to the police raids.
Police have reminded customers that legitimate companies adhere to health and safety standards, but the fake products are made in places where contamination is rife.
The counterfeit make-up industry is booming and sellers have been found to be exploiting millennials online.
The UK beauty industry is worth £4 billion and it is thought that social media has played a big part in the growth.
YouTube blogger Maya Gibson applied make-up with counterfeit goods for her channel and said: “After I used the make-up and took it off, my skin went absolutely mad – it did not react well at all.
“My skin went up in acne, my lips had partial chemical burns and bear in mind the make-up was only on my face for five minutes after filming.
“Quite a few of my friends own pieces of fake makeup – especially the Kylie lip kits – knowing that it’s fake. And when I’ve questioned them, they don’t think much of it which is scary, because they don’t particularly know the dangers.”