Fertilizer runoff hurts poor communities more, report says

Runoff of nitrates from fertilizer disproportionately harms low-income communities, especially since treating the water is often too expensive for cash-strapped towns and counties, the Midwest Center for Investigative Reporting found.

"Nitrogen contamination is linked to livestock production as the tons of nitrogen-rich manure produced by animal feeding operations is used as fertilizer in crop fields," Madison McVan reports. "While livestock operations must account for nitrogen levels in the soil and in the manure when applying manure to crop fields, the manure combined with commercial fertilizer can result in too much nitrogen being applied to the ground." Heavy rains often ferry the excess nitrogen into bodies of water where communities get their drinking water.

Nitrates are usually undetectable, and consuming large quantities can lower blood oxygen, especially among vulnerable populations such as children and immunocompromised people. Water treatment plants aren't generally equipped to filter them out, and adding such a system could cost millions, McVan reports.