If you believe the estimates, tens of billions of Euros, then a cost-benefit analysis might lead you to the same conclusion. I’ve always wondered about how these cost projections are done, and how valid they really are. For example, the estimates of how much revenue is lost by businesses during March Madness always seem ludicrously high to me. And the water and pharmaceutical industries have incentives to maximize their estimates. According to the article, many wastewater treatment plants need upgrading anyway, and there are several low-cost technologies that could substantially improve the quality of effluent.
The point I return to again and again is that it is much cheaper to prevent pollution than to clean it up. Restricting the authorization and use of these chemicals is recommended by many of the interested parties, and I agree with that.