Can a first world country let millions of its citizens be slowly poisoned on the grounds that it is too expensive to prevent it?

The last issue of The Economist has an article with a toxic title "Millions of Americans still get their drinking water from lead pipes" and on it, one gets to know that many Americans still risk lead poisoning from drinking water. One phrase says it all "At the current pace...residents won´t all get lead-free water until mid-26th century". 

PS - Ironically it's the same America that will spend billions on the development of new hypersonic weapons! https://www.nationaldefensemagazine.org/articles/2020/3/4/pentagon-to-spend-billions-mass-producing-hypersonic-weapons