Non-Point Source Pollution Envirothon Practice Test

Pet waste in waterways mainly introduces biological contaminants and nutrients. The feces carry bacteria, including disease-causing organisms and fecal-indicator bacteria, which signal contamination and can threaten human and animal health. At the same time, waste releases nutrients like nitrogen and phosphorus that fuel algae and aquatic plant growth. When these nutrients foster algal blooms, they can block sunlight, alter food webs, and lead to lower oxygen levels as algae decompose, harming fish and other aquatic life. Heavy metals, sediment, and chemical contaminants can come from other sources, but they’re not the primary pollutants associated with pet waste, making bacteria and nutrients the best description of the impact.