I personally would want factor 10 margin here. First I would assume that it is a distribution and if you are unlucky it still could be 10 years for a small qua

I personally would want factor 10 margin here. First I would assume that it is a distribution and if you are unlucky it still could be 10 years for a small quantile. If you think like this you will easily gets hundreds of those chemicals in your environment, so you will want that quantile to be really tiny. Additional I would assume that in reality even not all toxicity is independent. So effects might even add up. So better be safe than sorry. Also regulation is a driver for innovation. Without pressure, you will less likely get better products. It is better if companies put their dollars in research rather than lobbying.