This doesn't address the underlying problem, but if this is something you'd like to avoid as a consumer, it's worth noting that sewage sludge is not permitted for use in growing organic produce:
> A very important part of the process-based regulatory framework is the prohibition of certain methods in organic production and handling. Methods like irradiation, sewage sludge, and genetic engineering are all expressly prohibited from being used when growing or processing organic foods.
> A very important part of the process-based regulatory framework is the prohibition of certain methods in organic production and handling. Methods like irradiation, sewage sludge, and genetic engineering are all expressly prohibited from being used when growing or processing organic foods.
https://www.usda.gov/about-usda/news/blog/organic-101-what-o...