Whole effluent toxicity belongs to which pollutant category?

• A. Conventional
• B. Primary
• C. Toxic
• D. Nonconventional

Answer: (D)

Whole effluent toxicity is about the overall toxic effect of the entire wastewater discharge on aquatic life, not the presence of a single pollutant. It tests how the mixture of substances in the effluent affects organisms, capturing interactions among contaminants. Because this approach evaluates toxicity of the whole discharge rather than measuring a specific conventional parameter (like BOD, TSS, or pH), it falls under the nonconventional pollutant category. Conventional pollutants are the standard, concentration-based targets, while nonconventional (including toxicity-based assessments) covers substances and effects not captured by those standard measurements.