1.1ng is a very small amount, but the effect is really not that well understood. It’s definitely something we should minimise.

However it’s not a dangerous dose, it’s just the dose that produces detectable changes and we can detect really really small changes. The toxic dose is around 4g/kg body weight. So an average adult would need to consume over 300 grams of pure BPA to be poisoned by it.

Of course the answer is to use non-plastic containers, though the most common plastic used for food (PET - milk bottles, most soft drinks etc) don’t contain any BPA. It’s the reusable ones that do.

I have glass containers for food, though I do still use plastic ones for short term storage for things I won’t heat. Honestly this seems like the best answer, metal, wood and glass if you can.