Top tip. Buy used Lego cheap from ebay (or similar) and stick it in the dishwasher in a string bag. Try to avoid Lego from a smoker's house or that has been heavily gnawed. And keep the dishwasher heat low, unless you want Salvador Dali Lego.
Another tip: the quality difference between a Lego brand piece and its doppleganger from an AliExpress shop exists, but is usually negligible.
I never saw a piece that doesn't fit, and the difference was mostly color and durability, where the no-brand technic bricks would fail earlier than the Lego ones when (ab)used for mechanically straining purposes, like a coat hangers, cup holder etc.
The more interesting part: this opens up access to more original and specialized parts that Lego doesn't want or cares about, like a go pro mount for instance.
Technic bricks (or really pins, axles, wheels) are a nightmare for any house with small kids either way, I think food grade plastic is irrelevant on that side.
On the environmental impact it's a good point, especially EU regulations. I'm not sure yet how much Lego's stance is marketing and how much it actually makes a difference, especially as they also have a factory in China and the bricks I'd get would come from there, but one can hope.
Dishwashing and clothes washing are not designed to kill bacteria, even at high temperatures. They are designed to wash away bacteria. Detergent is a surfactant, it lifts bacteria/stains/dirt out of the material and then we wash them away. They are not usually anti-bacterial unless you buy a specific detergent that is
