I think you are asking where you can take hemp oil to be lab tested? Or perhaps you are asking where can you find hemp where it has been lab tested. If you are looking to take hemp you have for lab testing there are many cannabis laboratories throughout California including Steep Hill Labs, SC Labs, CW Analytical and more. As an individual you can always bring samples to labs for testing to ensure the purity of a product or to see all the potential nasty chemicals which could be inside!
If you are asking where to find lab tested hemp oil, I would not know the answer. For the most part, dispensaries are the ones that do lab testing on full spectrum cannabis products with THC, and even then you are not assured of what pesticides they have tested for. Many companies claim to have tested their products, including hemp, but again, without government regulations, you are having to trust their word for it. I would say you would be better off buying hemp products that are made from hemp from either Canada or Europe as the hemp from China is treated with harsh chemicals.
If you want to be absolutely sure, buy a product and have it tested yourself!
Hope this helps.