More PFAS regulations, lawsuits

*US imposes first-ever limits on levels of [four specific] toxic PFA substances in drinking water.*

No level of these substances is absolutely safe, but a smaller concentration causes a smaller danger. Even though no nonzero level leads to zero danger, a small enough level makes for a danger that is insignificant, practically speaking, compared with the other dangers of life. The effort to reduce PFA substance levels beyond that is not efficient reduction of the danger.