In the U. S., households contribute to nitrate pollution in surface waters via: a. fertilizer runoff and improperly treated sewage b. natural gas combustion and cooking fires c. fertilizer runoff and pesticide use household cleaning supplies and improperly treated sewage

c. fertilizer runoff and pesticide use household cleaning supplies and improperly treated sewage      

Explanation:

In the U.S., households contribute to nitrate pollution in surface waters via fertilizer runoff and pesticide use household cleaning supplies and improperly treated sewage. Common anthropogenic sources of nitrate pollution in the United States include fertilizers used for agricultural production and landscaping, animal manure, wastewater discharges from sewage treatment plants and septic systems, and fossil fuel combustion. The health impact of this is that most of these nitrates affect the water quality consumed by individuals thus imparting on their health negatively

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